Petition for Inter Partes Review of Patent No. 6,091,940 ...€¦ · Petition for Inter Partes...

Petition for Inter Partes Review of Patent No. 6,091,940

UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE PATENT TRIAL AND APPEAL BOARD

Qualcomm Incorporated and Qualcomm Atheros, Inc. Petitioners

v.

ParkerVision, Inc. Patent Owner

U.S. Patent No. 6,091,940

Filing Date: October 21, 1998 Issue Date: July 18, 2000

Title: Method and System for Frequency Up-Conversion

Inter Partes Review No. ______

PETITION FOR INTER PARTES REVIEW OF U.S. PATENT NO. 6,091,940

Table of Contents

-i-

I. INTRODUCTION ........................................................................................ 1

II. MANDATORY NOTICES UNDER 37 C.F.R. § 42.8(A)(1) .................... 2

A. Real Party-In-Interest Under 37 C.F.R. § 42.8(b)(1) ........................... 2

B. Related Matters Under 37 C.F.R. § 42.8(b)(2) .................................... 2

C. Lead and Back-Up Counsel under 37 C.F.R. § 42.8(b)(3) .................. 3

D. Service Information .............................................................................. 3

E. Power of Attorney ................................................................................ 3

III. PAYMENT OF FEES - 37 C.F.R. § 42.103 ................................................ 3

IV. REQUIREMENTS FOR INTER PARTES REVIEW UNDER 37 C.F.R. § 42.104 .............................................................................................. 4

A. Grounds for Standing Under 37 C.F.R. § 42.104(a) ............................ 4

B. Identification of Challenge Under 37 C.F.R. § 42.104(b) ................... 4

C. Each of the Cited References is Prior Art to the ‘940 Patent ............... 4

1. U.S. Patent 5,280,648 to Dobrovolny is prior art ...................... 4

2. Stephen A. Maas, Microwave Mixers, is prior art ..................... 5

3. “Active Doubly Balanced Mixers for CMOS RFICs” by Sullivan, et al. is prior art ........................................................... 5

D. Institution of Inter Partes Review Under 37 C.F.R. § 42.108(c) ........ 5

V. SUMMARY OF THE ‘940 PATENT ......................................................... 5

A. The Petitioned Claims of the ‘940 Patent ............................................ 6

B. Priority Date of the Petitioned Claims ................................................. 9

VI. BACKGROUND OF TECHNOLOGY RELATED TO THE ‘940 PATENT ........................................................................................................ 9

A. The Art of RF Circuit Design Was Advanced by 1998 ..................... 10

VII. CLAIM CONSTRUCTION UNDER 37 C.F.R. § 42.104(B)(3) ............. 11

1. Person of ordinary skill in the art ............................................. 11

2. “switch”/“switch module” ....................................................... 11

3. “to gate [a signal]”/“gating [a signal]” .................................... 13

4. “harmonic” ............................................................................... 14

5. “summer” ................................................................................. 16

Table of Contents (continued)

-ii-

VIII. OVERVIEW OF THE INVALIDATING REFERENCES .................... 17

A. Overview of Dobrovolny ................................................................... 18

B. Overview of Maas .............................................................................. 19

C. Overview of Sullivan ......................................................................... 20

D. Dobrovolny, Maas, and Sullivan Are Analogous Art ........................ 21

IX. APPLICATION OF THE PRIOR ART TO THE CLAIMS OF THE ‘940 PATENT .................................................................................... 21

A. Ground 1 – Dobrovolny and Maas Render Claim 1 and Dependent Claims 81, 82, 83, 84, 88, 89, 90, 91, and 94, and Claim 18 and Dependent claims 251, 252, 253, 254, 258, 259, 260, 261, and 264 Obvious Under 35 U.S.C. § 103(a) ...................... 21

1. Claim 1 ..................................................................................... 21

a. Dobrovolny discloses the preamble [1] ......................... 21

b. Dobrovolny and Maas render obvious elements [1a] and [1b] .................................................................. 22

c. Dobrovolny discloses element [1c] ............................... 40

d. Dobrovolny renders obvious element [1d] .................... 43

2. Claim 18 ................................................................................... 44

a. Dobrovolny discloses the preamble [18] ....................... 44

b. Dobrovolny and Maas render obvious elements [18a] and [18b] .............................................................. 44

c. Dobrovolny discloses element [18c] ............................. 46

d. Dobrovolny renders obvious element [18d] .................. 46

3. Claims 94 and 264.................................................................... 46

4. Claims 81, 82, 83, 84, 88, 89, 90, 91, 251, 252, 253, 254, 258, 259, 260, and 261 ............................................................. 48

B. Ground 2 – Dobrovolny in light of Maas and Sullivan Render Claims 86, 93, 256, and 263 Obvious Under 35 U.S.C. § 103(a) ...... 50

C. No Secondary Considerations of Non-Obviousness Exist ................. 52

X. CONCLUSION ........................................................................................... 52

List of Exhibits

-iii-

Exhibit No.

Description of Document

1001 U.S. Patent No. 6,091,940 to David F. Sorrells, et al.

1002 Lawrence Larson Declaration

1003 Krauss, Herbert L. et al., Solid State Radio Engineering

1004 U.S. Patent No. 5,680,078 to Ariie

1005 Sullivan, Patrick J., Ku, Walter H., Xavier, Bernard A., “Active Doubly Balanced Mixers for CMOS RFICs”, Microwave Journal, October 1, 1997

1006 Razavi, Behzad, RF Microelectronics

1007 Floyd, Thomas L., Electric Circuits Fundamentals, Third Edition

1008 ParkerVision Claim Construction Brief , ParkerVision, Inc. v. Qualcomm Incorporated, et al., Case No. 6:14-cv-00687-PGB-KRS (M.D.Fla.)

1009 Defendants’ Claim Construction Brief , ParkerVision, Inc. v. Qualcomm Incorporated, et al., Case No. 6:14-cv-00687-PGB-KRS (M.D.Fla.)

1010 Maas, Stephen A., Microwave Mixers (2nd Ed.)

1011 Couch, Leon W. II, Modern Communication Systems: Principles and Applications

1012 Curriculum Vitae of Dr. Lawrence E. Larson

1013 U.S. Patent No. 7,865,177 to Sorrells et al.

1014 Transcript of Jury Trial, Day Two, Examination of David Sorrells, ParkerVision, Inc. v. Qualcomm, Inc., 11-cv-00719, October 8, 2013

1015 RCA Corp., “RCA COS/MOS Integrated Circuits: Selection Guide/ Data / Application Notes,” 1974 (“RCA guide”)

1016 Carlson, Bruce A., Communication Systems: An Introduction to Signals and Noise in Electrical Communication (3rd Ed.), McGraw-Hill, Inc., 1986

List of Exhibits

-iv-

Exhibit No.

Description of Document

1017 U.S. Patent No. 1,699,570

1018 File History to European Application No. 01926955.4, filed November 2002

1019 The ARRL Handbook (72nd Ed.), The American Radio Relay League, Inc.

1020 Keys, Cynthia D., “Low-Distortion Mixers for RF Communications”

1021 Maemura, K. “The 200MHz- and 1.5GHZ-Band GaAs Monolithic Quadrature Modulator ICs”

1022 Larson, Lawrence, RF and Microwave Circuit Design for Wireless Communications.

1023 U.S. Patent No. 5,280,648 to Pierre Dobrovolny

1024 Smith, Bradford L., et al., Microwave Engineering Handbook

1025 Oppenheimer, Samuel L., Fundamentals of Electric Circuits

1026 Vizmuller, Peter, RF Design Guide: Systems, Circuits, and Equations, Vol. 1

1027 Couch, Leon W.II, Digital and Analog Communication Systems

1028 U.S. Patent No. 5,136,264 to Gregg Nardozza

1029 Encyclopedia of Electronics

1030 Illustrated Dictionary of Electronics

1031 Patent Owner’s Response to Motion to Construe “Pulse Shaping Module” “Pule Shaper” in ParkerVision, Inc. v. Qualcomm Incorporated, et al., Case No. 6:14-cv-00687-PGB-KRS (M.D.Fla.)

1032 U.S. Patent No. 5,027,163 to Pierre Dobrovolny

1033 Declaration from University of Washington

1034 Library of Congress – Catalog Information for RF and Microwave Circuit Design for Wireless Communications

1035 File History for U.S. Patent No. 6,091,940


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I. INTRODUCTION

Petitioners Qualcomm Incorporated and Qualcomm Atheros, Inc.

(“Petitioners” or “Qualcomm”) respectfully submit this petition for inter partes

review under 35 U.S.C. §§ 311-319 and 37 C.F.R. § 42 of claim 1 and dependent

claims 81-84, 86, 88-91, 93, and 94, and claim 18 and dependent claims 251-54,

256, 258-61, 263, and 264 (“Petitioned Claims”) of U.S. Patent No. 6,091,940 (Ex.

1001.)

The ʼ940 patent claims methods and systems to up-convert a signal. “The

up-conversion is accomplished by controlling a switch with an oscillating signal,

the frequency of the oscillating signal being selected as a sub-harmonic of the

desired output frequency.” (Ex. 1001, Abstract.) Although subharmonic

transmitters use oscillators that run at relatively low frequencies, they take

advantage of higher frequency “harmonic” signals that the mixer creates—thereby

achieving upconversion to very high frequencies without requiring high frequency

oscillators.

Sub-harmonic upconversion is an old concept. The ‘940 patent does not

claim or describe any new oscillator, amplifier, mixer, switch, filter, or other

component. The ‘940 patent concedes that all of the components recited in its

claims could be purchased “off-the-shelf.” (Ex. 1001, at 27:27 (“may be purchased

‘off-the-shelf’”), 28:26, 29:30, 30:38, 31:46 (same).) Because the concept of sub-


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harmonic mixers was old and their components were well-known, Patent Owner

claimed that the point of novelty was a new way of using a sub-harmonic mixer as

an up-converting transmitter. But sub-harmonic up-conversion is a concept nearly

as old as radio itself. United States Patent No. 1,699,570, issued to AT&T in 1929,

notes that “the applicant proposes to use the modulation of the voice currents with

a harmonic of the ‘carrier’ wave instead of the modulation of the voice with the

fundamental ‘carrier’ wave.” (Ex. 1017 at 1:56-1:60.)

None of the structures or concepts claimed in the ‘940 patent are novel and

the Petitioned Claims are invalid as obvious. Petitioners are reasonably likely to

prevail on each proposed ground presented in this Petition, and respectfully request

that the Board institute trial.

II. MANDATORY NOTICES UNDER 37 C.F.R. § 42.8(A)(1)

A. Real Party-In-Interest Under 37 C.F.R. § 42.8(b)(1)

Qualcomm is the real party-in-interest.

B. Related Matters Under 37 C.F.R. § 42.8(b)(2)

ParkerVision, Inc. (“Patent Owner”) asserted the ‘940 patent in

ParkerVision, Inc. v. Qualcomm Incorporated, et al., No. 6:14-cv-00687-PGB-

KRS (M.D. Fla.) (the “Related Litigation”). Qualcomm was served on August 28,

2014.

Petitioners are filing additional petitions for inter partes review on the ‘940


3

patent and on U.S. Patent Nos. 7,039,372 and 7,966,012, which are also assigned

to Patent Owner.

C. Lead and Back-Up Counsel under 37 C.F.R. § 42.8(b)(3)

Lead Counsel: Timothy S. Teter (No. 47,134) / [email protected] Back-up Counsel: Matthew J. Brigham (No. 44,047) / [email protected] Back-up Counsel: Eamonn Gardner (Reg. No. 63,322) / [email protected] Back-up Counsel: Orion Armon (Reg. No. 65,421) / [email protected] [email protected] Cooley LLP ATTN: Patent Group 1299 Pennsylvania Ave., NW, Suite 700 Washington, DC 20004 Tel: 650-843-5275 Fax: 650-849-7400

D. Service Information

The Petition is being served by FEDERAL EXPRESS to the attorneys of

record, Workman Nydegger, 60 East South Temple, Suite 1000, Salt Lake City UT

84111. Petitioners may be served by e-mail at the address provided above.

E. Power of Attorney

Filed concurrently with this petition per 37 C.F.R. § 42.10(b).

III. PAYMENT OF FEES - 37 C.F.R. § 42.103

This Petition requests inter partes review of twenty-four claims of the ‘940

patent: claim 1 and its dependent claims 81-84, 86, 88-91, 93, and 94, and claim 18

and its dependent claims 251-54, 256, 258-61, 263, and 264. This petition is

accompanied by a payment of $27,400, which includes excess claims fees. 37

C.F.R. § 42.15. This Petition meets the fee requirements of 35 U.S.C. § 312(a)(1).


4

IV. REQUIREMENTS FOR INTER PARTES REVIEW UNDER 37 C.F.R. § 42.104

A. Grounds for Standing Under 37 C.F.R. § 42.104(a)

Petitioners certify that the ‘940 patent is eligible for IPR and further certify

that Petitioners are not barred or estopped from requesting this IPR.

B. Identification of Challenge Under 37 C.F.R. § 42.104(b)

Petitioners request inter partes review of ‘940 patent claim 1 and dependent

claims 81-84, 86, 88-91, 93, and 94, and claim 18 and dependent claims 251-54,

256, 258-61, 263, and 264 and request that each claim be found unpatentable as

obvious under 35 U.S.C. § 103(a) on the following grounds:

Ground ‘940 Claims Basis for Challenge

1. 1 (81, 82, 83, 84, 88, 89, 90, 91, 94); 18 (251, 252, 253, 254, 258, 259, 260, 261, 264)

Obvious over U.S. Patent 5,280,648 to Dobrovolny in view of Stephen A. Maas, Microwave Mixers under 35 U.S.C. § 103(a)

2. 86, 93, 256, 263 Obvious over U.S. Patent 5,280,648 to Dobrovolny in view of Stephen A. Maas, Microwave Mixers, and “Active Doubly Balanced Mixers for CMOS RFICs” by Patrick J. Sullivan, et al. under 35 U.S.C. § 103(a)

This petition is accompanied by the Declaration of Dr. Lawrence E. Larson,

(Ex. 1002, “Larson Decl.”), an expert in the field.

C. Each of the Cited References is Prior Art to the ‘940 Patent

1. U.S. Patent 5,280,648 to Dobrovolny is prior art

U.S. Patent 5,280,648 to Dobrovolny (“Dobrovolny”) is prior art under 35


5

U.S.C. § 102(b) because it issued on August 16, 1991, more than a year before the

filing date of the ‘940 patent. (Ex. 1023.)

2. Stephen A. Maas, Microwave Mixers, is prior art

Stephen A. Maas’s Microwave Mixers, 2nd Ed. (“Maas”), is prior art under

35 U.S.C. § 102(b) because it was published in 1993, more than a year before the

filing date of the ‘940 patent. (Ex.1010.) Evidence of publication is provided by

the University of Washington Library. (Ex. 1033.)

3. “Active Doubly Balanced Mixers for CMOS RFICs” by Sullivan, et al. is prior art

“Active Doubly Balanced Mixers for CMOS RFICs” by Patrick J. Sullivan,

et al. (“Sullivan”) is prior art under 35 U.S.C. § 102(b) because it was published in

Microwave Journal on October 1, 1997, more than one year before the October 21,

1998, filing date of the ‘940 patent. (Ex. 1005.) Evidence of publication is

provided by the University of Washington Library. (Ex. 1033.)

D. Institution of Inter Partes Review Under 37 C.F.R. § 42.108(c)

Inter partes review of claim 1 and its dependent claims 81-84, 86, 88-91, 93,

and 94, and claim 18 and its dependent claims 251-54, 256, 258-61, 263, and 264

should be instituted because a reasonable likelihood exists that Petitioners will

prevail with respect to each of the claims challenged. 35 U.S.C. § 314(a).

V. SUMMARY OF THE ‘940 PATENT

The ‘940 patent generally claims an up-converting sub-harmonic mixer


6

comprising two switch modules, a summing device that sums the outputs of the

switch modules, and a filter for filtering out a desired harmonic signal. (Ex. 1001,

66:51-67:5.) Each of these structural components is highlighted in ‘940 Figure 18:

‘940 Patent Figure 18 (annotated) (Ex. 1001)

Other claims of the ‘940 patent recite additional elements such as a “pulse shaper”

that allegedly maximizes the number and amplitude of desired harmonics output by

the switch modules (Ex. 1001 at 69:19-32), or an “aliasing module” module that

downconverts a signal (Ex. 1001 at 69:54-67). The grounds presented below

demonstrate that the Petitioned Claims are invalid as obvious.

A. The Petitioned Claims of the ‘940 Patent

The elements of the Petitioned Claims are shown and labeled below:

Claim Limitation

[1] An apparatus for communicating, comprising:


7

[1a] a first switch module that receives a first oscillating signal and a first bias signal, wherein said first oscillating signal causes said first switch module to gate said first bias signal and thereby generate a first periodic signal having a first plurality of harmonics, said first periodic signal having an amplitude that is a function of said first bias signal;

[1b] a second switch module that receives a second oscillating signal and a second bias signal, wherein said second oscillating signal causes said second switch module to gate said second bias signal and thereby generate a second periodic signal having a second plurality of harmonics, said second periodic signal having an amplitude that is a function of said second bias signal;

[1c] a summer coupled to said first switch module and to said second switch module, said summer to receive and combine said first periodic signal and said second periodic signal, and to output a combined periodic signal having a combined plurality of harmonics; and

[1d] a filter coupled to said summer, said filter to isolate at least one of said combined plurality of harmonics.


[18a] a first switch module to receive a first oscillating signal and a first bias signal, wherein said first oscillating signal causes said first switch module to gate said first bias signal and thereby generate a first periodic signal having a first plurality of harmonics, said first periodic signal having an amplitude that is a function of said first bias signal, said first bias signal being a function of a first information signal;

[18b] a second switch module to receive a second oscillating signal and a second bias signal, wherein said second oscillating signal causes said second switch module to gate said second bias signal and thereby generate a second periodic signal having a second plurality of harmonics, said second periodic signal having an amplitude that is a function of said second bias signal, said second bias signal being a function of a second information signal;

[18c] a summer coupled to said first switch module and to said second switch module, said summer to receive and combine said first periodic signal and said second periodic signal, and to output a combined periodic signal


8

having a combined plurality of harmonics; and


[81] The apparatus of claim 1, wherein said first switch module is a electronic device.

[82] The apparatus of claim 81, wherein said electronic device is a semiconductor device.

[83] The apparatus of claim 82, wherein said semiconductor device is a transistor.

[84] The apparatus of claim 83, wherein said transistor is a field effect transistor.

[86] The apparatus of claim 84, wherein said field effect transistor is a complementary metal oxide semiconductor field effect transistor.

[88] The apparatus of claim 1, wherein said second switch module is a electronic device.





[94] The apparatus of claim 1, wherein said first plurality of harmonics are harmonics of the fundamental frequency of said first periodic signal and said second plurality of harmonics are harmonics of the fundamental frequency of said second periodic signal.

[251] The apparatus of claim 18, wherein said first switch module is an electronic device.


9





[258] The apparatus of claim 18, wherein said second switch module is an electronic device.






B. Priority Date of the Petitioned Claims

The priority date of the Petitioned Claims is October 21, 1998, the ‘940

patent filing date.

VI. BACKGROUND OF TECHNOLOGY RELATED TO THE ‘940 PATENT

Dr. Larson provides a technology tutorial in his declaration. (Ex. 1002 at ¶¶


10

40-101.)

A. The Art of RF Circuit Design Was Advanced by 1998

By 1996, the wireless communication industry was technically advanced.

(Ex. 1002, Larson Decl., at ¶ 102; Ex. 1022, Larson at 7-8.) Wireless

communications technologies had been in wide use in the consumer marketplace

for over fifteen years and rapid technological advancements in RF circuit design

had been achieved. (Ex. 1002 at ¶ 103; Ex. 1022 at 7 (“this field has developed so

rapidly that traditional communications and analog circuit design textbooks have

struggled to keep up with all of the advances in the field.”).) The technologically

advanced state of the radio transceiver industry influenced how RF circuit

designers worked. (Ex. 1002 at ¶ 105.) Circuit designers would survey the state-of-

the-art in radio transceiver component technology before commencing the design

process because mature component data was widely available. (Ex. 1022 at 14.)

Persons of ordinary skill in the art possessed a sophisticated understanding of the

possibilities for combining component technologies to satisfy the design

requirements for a given RF circuit application, and a high level of confidence that

the end result would work for its intended purpose. (Ex. 1002 at ¶ 106.)

As with the other components used in RF transceiver systems, the state of

the art of mixer technology was also advanced by 1996. Stephen Maas, a well-

known expert in RF mixers observed at the time, “[i]n the past twenty years, mixer


11

technology has evolved from a major research topic into one of great maturity.”

(Ex.1022 at 35.) The state of the art of RF circuit design in 1996 (i.e., two years

before the priority date of the ‘940 patent) was such that persons of ordinary skill

in the art routinely designed RF transceiver systems and RF circuit subcomponents

without inventive effort. (Ex. 1002 at ¶¶ 108-109.)

VII. CLAIM CONSTRUCTION UNDER 37 C.F.R. § 42.104(b)(3)

A claim subject to IPR is given its “broadest reasonable construction in light

of the specification of the patent in which it appears.” 37 C.F.R. § 42.100(b).

1. Person of ordinary skill in the art

A person of ordinary skill in the art as of October 1998 would possess, at a

minimum, either (a) a master of science degree in electrical engineering and two or

more years of experience in radio frequency circuit design, or (b) a bachelor of

science degree in electrical engineering with three or more years of experience

with the design and development of RF circuits. (Ex. 1002 at ¶¶ 24-29.)

2. “switch”/“switch module”

The term “switch” is well known in the art as a device that has two states:

the “closed” or “on” state (zero voltage across it, or the voltage is the same on each

side) and the “open” or “off” state (zero current through it). (Ex. 1003, Krauss at

77 (“[A] switch S that is either on (with zero voltage across it) or off (with zero

current through it) except for very brief periods of time during the transitions


12

between on and off states.”) (emphasis in original); id. at 21-23 and 76 (“an ideal

switch has either zero voltage across it or zero current through it at all times”); Ex.

1006, Razavi at 6 (“[I]n the simple circuit of Fig. 6.15(a), . . . the output is equal to

the RF input when S1 is on and zero when S1 is off.”)) The ‘940 patent uses the

terms “switch” and “switch module” consistent with that well-known definition.

For example, the ʼ940 patent describes the operation of a switch as taking one of

these two states:

This shaped signal is then used to control a switch which opens and

closes as a function of the frequency and pulse width of the shaped

signal.

(Ex. 1001 at 1:65-67.)

When the switch 2816 is “open,” the output 2822 of switch module

2802 is at substantially the same voltage level as bias signal 2806.

Thus, since the harmonically rich signal 2814 is connected directly to

the output 2822 of switch module 2802, the amplitude of

harmonically rich signal 2814 is equal to the amplitude of the bias

signal 2806. When the modulated oscillating signal 2804 causes the

switch 2816 to become “closed,” the output 2822 of switch module

2802 becomes connected electrically to the second input 2810 of

switch module 2802 (e.g., ground 2812 in one embodiment of the

invention), and the amplitude of the harmonically rich signal 2814

becomes equal to the potential present at the second input 2810.

(Ex. 1001 at 33:59-34:5.)


13

The broadest reasonable interpretation of “switch”/“switch module” is thus

“a device with an input and an output that can take two states, open and closed, and

when closed electrically connects its input and output such that the input and

output have an equal voltage.” (Ex. 1009, Defendants’ Claim Construction Brief at

13.)

In the Related Litigation, the Patent Owner proposed that “switch”/“switch

module” should be construed as “to generate a periodic signal having a plurality of

harmonics from an input signal and a control signal.” (Ex. 1008 at 16.) The Patent

Owner’s construction is not the broadest reasonable interpretation because it

describes a desired result rather than the claimed structure of a “switch” or “switch

module.” A device configured to operate as a “switch”/“switch module” is a

“switch”/“switch module” regardless whether it is producing the Patent Owner’s

desired results. Accordingly, the Patent Owner’s construction in erroneous. (Ex.

1002 at ¶¶ 114-117.)

3. “to gate [a signal]”/“gating [a signal]”

The term “to gate” or “gating” is used throughout the ʼ940 patent. The

specification of the ‘940 patent uses “gating” to describe the operation of a

“switch” or “switch module”: “[a]s the switch opens and closes, it gates a reference

signal which is the information signal.” (Ex. 1001 at 2:8-10.) Consistent with the

specification’s description that a switch “gates” a signal, a person of skill in the art


14

would understand “gating” as referring to the opening and closing (changing of

state) of the switch. (See also Section VII(2) above, discussion of “switch”/“switch

module”.) Therefore, the broadest reasonable interpretation of this term is “to

change/changing between (i) connecting a signal at an input to an output such that

the input and output have an equal voltage, and (ii) disconnecting the signal from

the output.” (See also, Ex. 1001 at 34:64-67, 36:33-57, and 41:44-42:19.)

In the Related Litigation, Patent Owner has proposed that this term means

“to generate a periodic signal having a plurality of harmonics from an input signal

and a control signal.” (Ex. 1008 at 16.) Patent Owner’s proposed construction is

improper because it describes a potential result of gating a signal using a switch in

a mixer, rather than what constitutes “gating”. (Ex. 1002 at ¶¶ 118-121.)

4. “harmonic”

The ʼ940 patent describes a device that is designed to create a large number

of “harmonic” frequencies (each an integer multiple of the lower, fundamental

frequency), allowing a stable, low frequency signal to be used to create higher

frequency signals. (Ex. 1001 at 1:45-52.) The ‘940 patent defines “harmonic” as a

frequency that is “compared to its fundamental or reference frequency” (and thus is

different from it) and “an integer multiple of” that fundamental frequency, where

the integer “‘n’ is 2, 3, 4, etc.”:


15

Harmonic: A harmonic is a frequency or tone that, when compared to

its fundamental or reference frequency or tone, is an integer multiple

of it. In other words, if a periodic waveform has a fundamental

frequency of ‘f’ (also called the first harmonic), then its harmonics

may be located at frequencies of ‘n•f,’ where “n” is 2, 3, 4, etc. The

harmonic corresponding to n=2 is referred to as the second harmonic,

the harmonic corresponding to n=3 is referred to as the third

harmonic, and so on.

(Ex. 1001 at 8:22-30.)

As used in the Petitioned Claims and in the definition quoted above,

“harmonic” does not include the fundamental frequency (i.e., “harmonic” excludes

n=1). This definition is consistent with every embodiment in the ʼ940 patent,

which describes and claims a transmitter that uses a low frequency oscillating

signal to create higher frequency harmonics that can be transmitted. Thus, the

broadest reasonable interpretation of “harmonic” is “a frequency or tone that is an

integer multiple of the frequency of the oscillating signal, i.e., if the oscillating

signal has a fundamental frequency of ‘f’ then its harmonics may be located at

frequencies of ‘n•f,’ where ‘n’ is 2, 3, 4, etc.” Defining “harmonic” to be a multiple

(n>1) is consistent with technical dictionaries at the time. (Ex. 1030, Illustrated

Dictionary of Electronics, at 6 (defining “harmonic” to be “…a multiple of the

FUNDAMENTAL FREQUENCY by a whole-number factor of 2 or more”).)

In the Related Litigation, the Patent Owner argued that the fundamental


16

frequency (n=1) should be included within the definition of “harmonic” because

the specification of the ‘940 patent refers to the fundamental frequency as the “first

harmonic.” (Ex. 1008 at 9-12.) But the Patent Owner ignored the context of those

statements, the context of the claims, and the ‘940 specification. For example, in

ʼ940 Figure 14, the only purpose of the switch module is to generate higher

frequency signals that can be transmitted (i.e., to upconvert); the switch module

would be superfluous if “harmonic” included the fundamental frequency (n>1). In

other words, if the claimed “harmonic” included the fundamental frequency (n=1),

then the “switch module” would have no purpose and, in fact, would be

detrimental to the operation of the system. (Ex. 1002 at ¶¶ 122-125.)

5. “summer”

The claimed “summer” adds two voltages, as shown in every embodiment in

the ‘940 patent. Thus, the broadest reasonable interpretation of “summer” is “a

device that sums two or more signals.” This construction is consistent with the

description of the summer in the ʼ940 patent. (See Ex. 1001 at 37:22-27 (“The

invention supports numerous embodiments of the summer. Exemplary

embodiments of the summer 3402 (FIG. 34) are described below. However, it

should be understood that these examples are provided for illustrative purposes

only. The invention is not limited to these embodiments.”).)

In the Related Litigation, the Patent Owner proposed that the claimed


17

“summer” does not need to be a device, but instead, can be nothing more than a

connection between two wires. (Ex. 1008 at 32-34.) To support its infringement

theory, the Patent Owner proposed that the term “summer” be construed to mean

“a circuit that produces a signal which is the arithmetic sum of two or more

signals.” (Ex. 1008 at 32.) The Patent Owner’s construction is erroneous; a

connection between two wires cannot add voltages together because it would

violate Kirchhoff’s Voltage Law, which requires that all points along a wire

(assuming substantially zero resistance), and all inputs to a node, have the same

voltage. (Ex. 1007, Floyd, at 8 (“the algebraic sum of all the voltages around a

closed path is zero”).) Petitioners’ construction is consistent with the broadest

reasonable interpretation of the claim language and specification—the claimed

“summer”/“summing means” is “a device that sums two or more signals.” (Ex.

1002 at ¶¶ 126-127.)

VIII. OVERVIEW OF THE INVALIDATING REFERENCES

The Petitioned Claims of the ‘940 patent are invalid for obviousness in light

of the teachings of the prior art references described below. In particular, U.S.

Patent 5,280,648 to Dobrovolny describes the structure of the Petitioned Claims.

Maas, Microwave Mixers, teaches persons of ordinary skill in the art how to use

that structure to generate and isolate higher frequency harmonics, and Sullivan

teaches persons of ordinary skill in the art to make such devices using well-known


18

CMOS technology and FETs. None of the prior art references supporting the

invalidity grounds in this petition were before the patent examiner during the

patent examination process.

A. Overview of Dobrovolny

U.S. Patent 5,280,648 to Dobrovolny discloses a device for upconverting.

(Ex. 1023 at 1:18-22, Figs. 1-4.) Figures 1 and 2 of Dobrovolny disclose a system

that upconverts a high level RF signal 10. (Ex. 1023 at 2:49-55, Figs. 1-2.) Figure

1, below, shows key components of the upconverter, including high level RF signal

10 coupled to bifilar balun 11 which inverts the signal (creating one non-inverted

signal and one inverted signal phase shifted 180°). (Ex. 1023 at 2:49-3:47, Figs. 1-

3.) A square wave symmetric local oscillating signal is generated from LO Source

40. (Id.) The LO Source includes a balun that inverts one local oscillator signal

relative to the other by 180°. (Id.) The upconverter includes two GaAs MESFET

switches 22 and 26 that operate under control of the local oscillating signals. (Id.)

In combination with the operation of the switches, trifilar transformer 14 sums the

voltages of the signals generated by the switches, producing a waveform C at the

IF Out port that includes multiple harmonics. (Id.) Annotated Figure 1 shows the

key aspects of Dobrovolny’s upconverter:


19

Dobrovolny Fig. 1 (annotated) (Ex. 1023)

B. Overview of Maas

Dobrovolny describes the structure of the ‘940 patent—Maas encourages

persons of ordinary skill to use that structure as claimed in the ‘940 patent. In

particular, Maas encourages persons of ordinary skill in the art to use mixers (such

as the Dobrovolny design) to generate higher frequency harmonics, which can then

be selected for transmission. Microwave Mixers, Second Edition, by Stephen A.

Maas was published in 1993 by Artech House, Inc. (Ex. 1010.) Maas’s book

teaches the fundamentals of mixer design, mixer theory, and how to

subharmonically drive a mixer to generate harmonics that can be filtered at the


20

output to achieve up-conversion. (Ex. 1010, Maas at 9-10 and 25-26.)

As Maas explains, a “sub-harmonically pumped mixer” is driven at a

frequency lower than that of the desired local oscillator (LO) signal—the strategy

that the ‘940 patent embraces. (Ex. 1010 at 25.) For example, Maas discusses

pumping (driving) the mixer at half the LO frequency and mixing the RF signal

with the second harmonic of the junction’s conductance waveform. (Ex. 1010 at

25.) The motivation for such a sub-harmonic architecture is that “it is expensive,

inconvenient, or even impossible to generate a fundamental-frequency LO” in

many applications. (Ex. 1010 at 25.) Thus, persons of ordinary skill in the art

would have been motivated to use the Dobrovolny structure to generate high

frequency harmonics, for reduced expense and enhanced convenience.

C. Overview of Sullivan

The article “Active Doubly Balanced Mixers for CMOS RFICs” was

published by Patrick J. Sullivan, et al. in Microwave Journal on October 1, 1997

(hereafter “Sullivan”). Sullivan is directed to mixers for CMOS RF integrated

circuits. (Ex. 1005, Sullivan, at Title, 1, 3.) Sullivan teaches that CMOS FETs are

alternatives to MESFET switches in mixers like Dobrovolny’s: “The drive to

increase transceiver integration and reduce transceiver cost makes CMOS an

attractive technology for low cost, highly integrated transceivers.” (Ex. 1005 at 9.)


21

D. Dobrovolny, Maas, and Sullivan Are Analogous Art

The prior art references supporting the proposed grounds are analogous art

to the ‘940 patent because each prior art reference concerns RF upconverters and

RF circuit design. Accordingly, it would have been obvious to an RF circuit

designer in 1998 to consult and combine the teachings of the cited prior art

references.

IX. APPLICATION OF THE PRIOR ART TO THE CLAIMS OF THE ‘940 PATENT

A. Ground 1 – Dobrovolny and Maas Render Claim 1 and Dependent Claims 81, 82, 83, 84, 88, 89, 90, 91, and 94, and Claim 18 and Dependent claims 251, 252, 253, 254, 258, 259, 260, 261, and 264 Obvious Under 35 U.S.C. § 103(a)

Dobrovolny in light of Maas renders independent claim 1 and dependent

claims 81, 82, 83, 84, 88, 89, 90, 91, and 94, and independent claim 18 and

dependent claims 251, 252, 253, 254, 258, 259, 260, 261, and 264 obvious under

35 U.S.C. § 103(a) for the reasons set forth below:

1. Claim 1

a. Dobrovolny discloses the preamble [1]


Dobrovolny discloses an apparatus for communicating: “This invention

relates in general to CATV mixers and in particular to commutating type single

and double-balanced resistive RF mixers that are operable with high level RF input

signals.” (Ex. 1023 at 1:14-17.) “CATV” refers to “community antenna television”


22

or “Cable TV.” (Ex. 1002 at ¶ 133.) “RF” refers to “radio frequency.” (Ex. 1023 at

1:22.) Accordingly, Dobrovolny discloses an apparatus for communicating radio

frequency television signals.

b. Dobrovolny and Maas render obvious elements [1a] and [1b]

[1a] a first switch module that receives a first oscillating signal and a first bias signal, wherein said first oscillating signal causes said first switch module to gate said first bias signal and thereby generate a first periodic signal having a first plurality of harmonics, said first periodic signal having an amplitude that is a function of said first bias signal;

[1b] a second switch module that receives a second oscillating signal and a second bias signal, wherein said second oscillating signal causes said second switch module to gate said second bias signal and thereby generate a second periodic signal having a second plurality of harmonics, said second periodic signal having an amplitude that is a function of said second bias signal;

Dobrovolny in light of Maas discloses claim elements [1a] and [1b].

Dobrovolny describes two different types of upconverter (single and double-

balanced mixers). This Petition will focus on Dobrovolny’s description of a single-

balanced mixer comprised of two switches that satisfies all of the structural

limitations of elements [1a] and [1b]. Maas teaches how to subharmonically pump

Dobrovolny’s upconverter to generate desired harmonics. Each sub-element of [1a]

and [1b] is addressed below.

(1) Claim element 1(a)(i) “first switch module” and 1(b)(i) “second switch module”

Dobrovolny discloses a “first switch module” and a “second switch


23

module”. The broadest reasonable interpretation of “switch module” is “a device

with an input and an output that can take two states, open and closed, and when

closed electrically connects its input and output such that the input and output have

an equal voltage.” (Ex. 1002 at ¶ 135, 191.)

Figure 1 of Dobrovolny shows an upconverter that includes two Gallium

arsenide (“GaAs”) metal–semiconductor field effect transistor (“MESFET”)

switches 22 and 26: “Windings 16 and 17 have their other terminals connected to

respective drain electrodes of a pair of GaAs MESFET devices 22 and 26,

respectively. These devices may comprise, for example, NEC MESFETS

NE72084.” (Ex. 1023 at 2:60-64.) As Dobrovolny’s characterization underscores,

MESFET switches are devices.

Referring to an equivalent embodiment in the “single-balanced resistive

mixer of the cross-referenced application Ser. No. 281,156, U.S. Pat. No.

5,027,163,” Dobrovolny confirms that the MESFETS act as switches, noting that

the “pair of GaAs MESFETS” are “for high speed switching.” (Ex. 1023 at 1:66-

67; 2:2-3 (emphasis added); Ex. 1032, Pat. 5,027,163 at Fig. 1.) GaAs MESFET 22

satisfies the “first switch module” limitation and MESFET 26 satisfies the “second

switch module” limitation.

Switches 22 and 26 are capable of taking two states (open and closed),

determined by the local oscillating control signal. (Ex. 1003 at 77 (“[A] switch S


24

that is either on (with zero voltage across it) or off (with zero current through it)

except for very brief periods of time during the transitions between on and off

states.”); id. at 21-23 and 76 (“an ideal switch has either zero voltage across it or

zero current through it at all times”).)

As is understood by those of skill in the art, when switches 22 and 26 are

closed (or on) they electrically connect the input and output so that both are at an

equal voltage. (Ex. 1006 at 6 (“[I]n the simple circuit of Fig. 6.15(a), . . . the output

is equal to the RF input when S1 is on and zero when S1 is off.”); Ex.1003 at 76

and 77; Ex. 1002 at ¶¶ 140, 197.)

In Figure 2, Dobrovolny provides a simplified schematic diagram of the

upconverter shown in Figure 1. Dobrovolny explains that “MESFETS 22 and 26

are represented by switches 22’ and 26’, respectively, and are effective to

alternately connect the free terminals of windings 16 and 17 to ground when the

switches 22’ and 26’ are closed under control of LO 40, i.e., at the local oscillator

frequency.” (Ex. 1023 at 3:20-25.) Figure 2 is shown below, with switches 22’ and

26’ labeled:


25

Dobrovolny Figure 2, Annotated (Ex. 1023)

Switches 22 and 26 electrically connect their inputs and outputs when they

close. “MESFETS 22 and 26 are represented by switches 22’ and 26’, respectively,

and are effective to alternately connect the free terminals of windings 16 and 17 to

ground when the switches 22’ and 26’ are closed under control of LO 40, i.e., at

the local oscillator frequency.” (Ex.1023 at 3:20-25.) The input (RF In) and output

(IF Out) of each respective switch 22 and 26 becomes connected when “the free

terminals of windings 16 and 17” are alternately connected to common ground

across each switch. When switch 22 closes, the voltage in winding 16 develops at

the IF output terminal 25; during this time switch 26 is open and no output voltage

is induced due to output winding 17. (Ex. 1023 at 3:17-30; Ex. 1002 at ¶ 144, 200.)

When switch 26 closes, the voltage in winding 17 develops at IF Output terminal

25; during this time switch 22 is open and no output voltage is induced due to

output winding 16. (Ex. 1023 at 3:17-30; Ex. 1002 at ¶ 144, 200.) Annotated

Figure 1 shows each switch, windings 16 and 17 and IF Output terminal 25:


26


(2) Claim element 1(a)(ii) “first oscillating signal” and

1(b)(ii) “second oscillating signal”

Dobrovolny discloses first and second switch modules that receive first and

second oscillating signals. Switches 22 and 26 are connected to and receive first

and second oscillating signals from local oscillator (“LO”) source 40. Dobrovolny

confirms that “the drain-source circuits of a pair of FET transistors … are

alternately activated by a symmetric local oscillator signal.” (Ex. 1023 at Abstract.)

The “first oscillating signal” and “second oscillating signal” are carried on the

wires connecting the LO Source to the switches 22 and 26. Dobrovolny’s

discussion of Figure 2 reiterates that “[t]he MESFETS 22 and 26 are represented

by switches 22' and 26', respectively, and are effective to alternately connect the

free terminals of windings 16 and 17 to ground when the switches 22' and 26' are


27

closed under control of LO 40, i.e., at the local oscillator frequency.” (Ex. 1023

at 3:20-25 (emphasis added).) The first and second switch modules and first and

second oscillating signals are shown in the annotated version of Figure 1 below:


A person of ordinary skill in the art would understand that the first and

second oscillating signals have the same amplitude but are out of phase by 180°.

This understanding is based on Dobrovolny’s disclosure, which (1) states that “the

signal from local oscillator 40 is symmetrical”, (2) shows two different signals

leaving the LO Source functional block, and (3) explains that the local oscillator

signals “alternately connect the free terminals of windings 16 and 17 to ground

when the switches 22´ and 26´ are closed under control of LO 40, i.e., at the local

oscillator frequency.” (Ex. 1023 at 3:22-26.) The alternating switching action of

the FET switches 22 and 26 results from the 180° phase difference in the two


28

oscillating signals, which causes one switch to open when the other is closed. (Ex.

1002 at ¶¶ 148, 204.)

Persons of ordinary skill in the art recognize that symmetric signals

produced by the application of a signal to a phase splitting network satisfy the

“first” and “second” local oscillating signal elements because the phase of the

signals is different (i.e., one is non-inverted at 0° and the other is inverted 180° out

of phase relative to the first signal). (See, e.g., Ex. 1003, Krauss at 80 (“The audio

input signal is applied to a phase-splitting network that produces two audio

signals that differ in phase by 90°. These signals are then applied to two double-

balanced mixers…”)(emphasis added); Ex. 1002 at ¶ 152.)

Annotated Dobrovolny Figure 2 below illustrates the phase shifted local

oscillating signals generated by LO Source 40. The LO Signal waveform is copied

from Figure 3(b), which shows “a local oscillator-controlled polarity multiplier

(i.e., representing the action of LO-controlled switches 22´ and 26´).” (Ex. 1023 at

3:33-35.)


29


(3) Claim element 1(a)(iii) “first bias signal” and 1(b)(iii) “second bias signal”

Dobrovolny discloses first and second switch modules that receive first and

second bias signals. The ʼ940 patent explains that “[i]t is well known to those

skilled in the relevant art(s) that the information signal 5650 may be used as the

bias/reference signal 5646 directly without being summed with a bias signal.” (Ex.

1001 at 57:1-4 (emphasis added).) In other words, the ʼ940 patent defines “bias

signals” as encompassing information signals. (Ex. 1002 at ¶¶ 154, 210.)

Dobrovolny discloses a High Level Radio Frequency (“RF”) Source 10. The RF

signal contains the information that television watchers see and hear. (Ex. 1023 at

1:14-17.) Therefore, the RF Source signals are information signals that constitute

“bias signals” as that term is defined by the ‘940 patent. (Ex. 1002 at ¶¶ 154, 210.)

The signal from RF Source passes through a balun transformer 11 which


30

generates first and second bias signals that are 180° out of phase with each other.

(Ex. 1024, Microwave Engineering Handbook, at 8 (“The two outputs of balun are

equal in amplitude and at 180° in phase.”) The signals generated by balun 11 travel

through trifilar transformer 14 and appear as an RF Input on winding 15, which

“induces like-polarity voltages of equal value” in windings 16 and 17. (Ex. 1023 at

3:17-20.) These signals are also 180° out of phase with each other. It is well known

to persons of ordinary skill in the art that a transformer with a center tapped

secondary winding (like trifilar transformer 14), outputs two equal voltages with

exactly opposite polarities in their secondary windings. (Ex. 1025, Oppenheimer,

at 3 (“a center tapped transformer … allows us to obtain two equal voltages with

exactly opposite polarities).)

Persons of ordinary skill in the art recognize that the symmetric RF In

signals produced by the application of the RF In signal to a phase splitting network

(i.e., balun 11) are “first” and “second” bias signals because the phase of the

signals is different (i.e., one is non-inverted at 0° and the other is inverted 180° out

of phase relative to the first signal). (See, e.g., Ex. 1003 at 80 (“The audio input

signal is applied to a phase-splitting network that produces two audio signals

that differ in phase by 90°. These signals are then applied to two double-balanced

mixers…”) (emphasis added); Ex. 1002 at ¶¶ 158, 214.)

Dobrovolny confirms the presence of the symmetrical RF Input signals,


31

which constitute the first and second bias signals. (Ex. 1023 at 3:25-27 (“As

mentioned, the signal from local oscillator 40 is symmetrical, as is the RF input

signal across winding 15.” (emphasis added).) The first and second bias signals,

out of phase with each other by 180° are shown in annotated Figure 2, below.

Again, Figure 2 is a simplified version of Figure 1, and the RF In signal

illustrations are from Figure 3:


(4) Claim element 1(a)(iv) “gating first bias signal” and

1(b)(iv) “gating second bias signal”

The broadest reasonable interpretation of “gating first/second bias signal” is

“to change/changing between (i) connecting a signal at an input to an output such

that the input and output have an equal voltage, and (ii) disconnecting the signal

from the output.” (Ex. 1002 at ¶¶ 164-166.) Dobrovolny discloses first and second

switch modules that receive first and second oscillating signals and first and

second bias signals, wherein the oscillating signals cause the switch modules to


32

gate the bias signals.

Dobrovolny Figure 2, annotated below, shows the local oscillator signals

causing the first and second switch modules to alternately gate the first and second

bias signals.


Dobrovolny’s written description reinforces that the oscillating signals cause

the switches 22’ and 26’ in Figure 2 to close at the local oscillator frequency,

which connects and disconnects the RF In signals at the drain D of each switch

with the source S, which is connected to a common ground:

“The MESFETS 22 and 26 are represented by switches 22' and 26',

respectively, and are effective to alternately connect the free terminals

of windings 16 and 17 to ground when the switches 22' and 26' are

closed under control of LO 40, i.e., at the local oscillator

frequency.”

(Ex. 1023 at 3:20-25 (emphasis added).)

Dobrovolny Claim 1 confirms the effect of the local oscillator signals,


33

claiming “a symmetrical local oscillator signal for alternately activating the gate

terminals of each of said first and second pairs of transistors [in MESFET

switches].” (Ex. 1023 at 5:33-35.) “Activating the gate terminals of … the

transistors” in switches 22 and 26 constitutes causing the first or second switch

modules to gate the first and second bias signals. When switches 22 and 26

alternately close, the voltage induced in winding 16 or 17 is connected through

drain D of each switch to common ground, which induces a voltage at IF Out. (Ex.

1023 at 3:17-30.) When a switch is closed, the voltage across the switch is equal.

(Ex. 1006 at 6 (“[I]n the simple circuit of Fig. 6.15(a), . . . the output is equal to the

RF input when S1 is on and zero when S1 is off.”); Ex. 1003 at 76-77.) When the

switches are open, the RF In signal is disconnected from the output. (Id.)

If the Patent Owner’s proposed construction for this term were adopted, “to

gate” or “gating” would mean “generating a periodic signal having a plurality of

harmonics from an input signal and a control signal.” Dobrovolny discloses this

limitation under Patent Owner’s proposed construction. (Ex. 1002 at ¶¶ 170, 226.)

Dobrovolny’s disclosure describes the input signal and control signal, noting that

the effect of driving the MESFET switches 22 and 26 at the local oscillator

frequency is to “commutate or switch the polarity of the RF signal developed at the

IF output terminal, the switching rate determined by the local oscillator

frequency.” (Ex. 1023 at 3:25-30.) Dobrovolny adds that “[i]t will be understood


34

that waveform C [in Figure 3] includes a multiplicity of harmonics, including the

desired IF output frequency which may be derived by suitable filtering.” (Ex. 1023

at 3:37-40.)

(5) Claim element 1(a)(v) “first periodic signal having a first plurality of harmonics” and 1(b)(v) “second periodic signal having a second plurality of harmonics”

Dobrovolny renders these limitations obvious in view of the teachings of

Maas. Dobrovolny discloses every structural component recited in claim 1 and

further discloses that the claimed single balanced mixer generates a “multiplicity of

harmonics, including the desired IF output frequency which may be derived by

suitable filtering.” (Ex. 1023 at 3:37-40.) Maas complements Dobrovolny’s

teachings by teaching how any mixer (including Dobrovolny’s upconverter) could

be subharmonically pumped to generate desired higher frequency harmonics that

could be isolated to accomplish up-conversion.

In the Related Litigation, Patent Owner proposes a broad construction of

“harmonic,” arguing that “harmonic” is “a frequency or tone that, when compared

to its fundamental or reference, is an integer multiple including the fundamental

(n=1).” (Ex.1008 at 9.) Petitioners’ proposed construction of “harmonic” is “a

frequency or tone that is an integer multiple of the frequency of the oscillating

signal, i.e., if the oscillating signal has a fundamental frequency of ‘f’ then its

harmonics may be located at frequencies of ‘n•f,’ where ‘n’ is 2, 3, 4, etc.” (Ex.


35

1009 at 20.) The combined teachings of Dobrovolny and Maas satisfy limitations

1(a)(v) and 1(b)(v) under either construction.

Dobrovolny discloses that the intermediate frequency (IF) signal developed

at the output of the circuit in Figures 1 and 2 has a “multiplicity of harmonics”

including the desired IF output frequency, which may be derived (isolated) by

filtering:

Reference to FIG. 3 shows the effects of the commutation action, with

waveform A representing an RF input signal; waveform B, a local

oscillator-controlled polarity multiplier (i.e., representing the action of

LO controlled switches 22' and 26'); and waveform C, the resultant

output signal available at the IF output terminal of the mixer. It will

be understood that waveform C includes a multiplicity of

harmonics, including the desired IF output frequency which may

be derived by suitable filtering.

(Ex. 1023 at 3:31-40 (emphasis added).)

The voltage “waveform C” represents the sum of the voltages induced in

windings 16 and 17 by operation of the first and second switch modules. Each of

the first and second periodic signals would have a plurality of harmonics. (Ex.

1002 at ¶ 172, 228.) The structure of Dobrovolny’s single-balanced mixer is

symmetrical and contains the same switching elements on each side of the circuit.

As a result, the number and frequency of the harmonics generated by each switch

would be similar. (Ex. 1002 at ¶ 172, 228.) The difference between the standalone


36

waveforms and the summed “waveform C” depicted in Figure 3(c) is that, in a

single balanced mixer “when a 180° hybrid is used [like the mixer taught by

Dobrovolny], the even harmonics of one of the input signals are suppressed

(usually the harmonics of the LO signal).” (Ex. 1024 at 8.)

Maas teaches that it was scientifically and mathematically proven well

before the earliest priority date of the ‘940 patent that a switch used as a mixer (as

in Dobrovolny’s mixer) generates a range of output frequencies, including

harmonics: “[t]he use of a nonideal multiplier results in the generation of LO

harmonics and in mixing products other than the desired one. The desired output

frequency component must be filtered from the resulting mess.” (Ex. 1010 at 24.)

Maas explains that mixer output frequencies can be calculated using the

relation:

fIF = mfRF + nfLO

where

m, n = 0, ±1, ±2,…

And fIF, fRF, and fLO are the IF, RF, and LO frequencies.

(Ex. 1010 at 24.)

Maas also teaches that it is preferential in certain circumstances to drive an

upconverter (such as a mixer) at a sub-multiple of the desired frequency (i.e.,

subharmonic mixing as claimed in the ‘940 patent) and select the corresponding


37

harmonic at the desired frequency (e.g., use oscillating signal at 1/3 desired

frequency and select the third harmonic; use oscillating signal at 1/5 desired

frequency and select the fifth harmonic; etc.):

For many applications, it is expensive, inconvenient, or even

impossible to generate a fundamental-frequency LO. … In these

cases, it may be wise to use a mixer that is pumped at half the LO

frequency, and to mix the RF signal with the second harmonic of the

junction’s conductance waveform.

(Ex. 1010 at 25-26.)

To summarize, Maas teaches the person of ordinary skill in the art how to

use well-known mathematical formulas to calculate the frequencies at which

harmonics are generated given known LO and RF input frequencies and how to

subharmonically pump a mixer at a frequency that will generate desired harmonics

at the output that can be used for frequency up-conversion. (Id.)

(a) Combining the Teachings of Dobrovolny and Maas Would be Obvious

It would be obvious to combine the teachings of Dobrovolny with Maas for

at least two reasons, including PTO Exemplary Rationale (G), “some teaching,

suggestion, or motivation to combine,” and Rationale (D), “applying a known

technique to a known device ready for improvement to yield predictable results.”

A person of ordinary skill in the art would be expressly motivated to apply

Maas’s teachings to Dobrovolny’s because Dobrovolny states that “[i]t will be


38

understood that waveform C includes a multiplicity of harmonics, including the

desired IF output frequency, which may be derived by suitable filtering.” (Ex. 1023

at 3:37-40.) In other words, Dobrovolny teaches that one of the multiplicity of

harmonics is the desired IF output frequency, which would motivate a person of

ordinary skill in the art to consult Maas’s teaching how to subharmonically pump

the mixer and mathematically identify a desired harmonic in the mixer output

signal, such as non-suppressed odd-order harmonics where n=3, 5, 7, etc. (Ex.

1002 at ¶¶ 178, 181, 234, 237; MPEP § 2143(g).)

It would also be obvious to apply Maas’s known technique of

subharmonically pumping a mixer to accomplish up-conversion to Dobrovolny’s

known device. Applying Maas’s teachings to Dobrovolny’s mixer would improve

the operation of the mixer and yield predictable results without requiring any

structural modifications in the mixer itself. (Ex. 1002 at ¶ 183-184, 239-240;

MPEP § 2143(d).)

(6) Claim element 1(a)(vi) “first periodic signal having an amplitude that is a function of said first bias signal” and 1(b)(vi) “second periodic signal having an amplitude that is a function of said second bias signal”

Dobrovolny discloses that the first and second periodic signals generated by

the first and second switch modules have amplitudes that are a function of the first

and second bias signals. “Amplitude” measures “the strength of a signal,” and


39

“can be defined in terms of current, voltage, or power.” (Ex. 1029, Encyclopedia of

Electronics at 6-7.) The amplitudes of the periodic signals that emerge from the

switch modules 22 and 26 are a function of the first and second bias signals

because of the inherent properties of Dobrovolny’s claimed mixer. “Mixers

faithfully preserve the amplitude and phase properties of signals at the RF port.

Signals can therefore be translated in frequency without affecting their modulation

properties.” (Ex. 1026, Vizmuller at 5 (emphasis added).) In other words, as the RF

Design Guide explains, the amplitude of the periodic signals that emerge from the

mixer are functions of the first and second bias signals (the non-inverted and

inverted RF In signals) because the mixer “faithfully preserve[s] the amplitude” of

signals at the RF port (i.e., the bias signals) while up- or down-converting their

frequency. (Id.)

Dobrovolny graphically illustrates the relationship between the periodic

signals output by the mixer (represented by waveform C in Figure 3) and the first

and second bias signals (represented by waveform A in Figure 3). The amplitude

of the waveform C is the same for the bias signal and periodic signal—only the

frequency of the signals changes:


40


The waveforms of the first and periodic signals alone (i.e., unsummed)

would be identical to waveform C, which is summed, but include even-order

harmonics from the local oscillator signals. (Ex. 1002 at ¶ 189, 245; Ex. 1024 at 8

(“when a 180° hybrid is used [in a single balanced mixer], the even harmonics of

one of the input signals are suppressed (usually the harmonics of the LO signal.”).)

c. Dobrovolny discloses element [1c]


The broadest reasonable interpretation of “summer” is “a device that sums

two or more signals.” (Ex. 1002 at ¶ 246-247.) Dobrovolny discloses this limitation

under either proposed construction.

Figures 1 and 2 of Dobrovolny disclose a trifilar transformer 14 that includes


41

input winding 15 and a pair of output windings 16 and 17, which connect at center

tap 18 in the secondary of the transformer. (Ex. 1023 at 2:49-3:40; Figs. 1-3.)

Transformer 14 is coupled to switches 22 and 26 and in combination with their

operation, sums the voltages generated by the switches, producing a waveform C at

the IF Out port that includes a multiplicity of harmonics. (Id.) The voltage

summing is equivalent to (1,0,1,0,1…)*Vin + (0,1,0,1,0…)*-Vin, which represents

the sum of voltages on each coil modulated by switching. (Ex. 1002 at ¶ 248.)

Annotated Figure 1, which is combined with Dobrovolny Figure 3(c), illustrates

that the signals output from each switch are summed into a single voltage signal:


Dobrovolny describes the operation of the switches in combination with

transformer as follows, and explains that a single, combined periodic signal


42

develops at the IF output terminal:

As indicated, winding 15 serves as an RF input and induces like

polarity voltages of equal value in serially connected windings 16 and

17. The MESFETS 22 and 26 are represented by switches 22' and 26',

respectively, and are effective to alternately connect the free terminals

of windings 16 and 17 to ground when the switches 22' and 26' are

closed under control of LO 40, i.e., at the local oscillator frequency.

As mentioned, the signal from 25 local oscillator 40 is symmetrical, as

is the RF input signal across winding 15. The effect of these signals

is to commutate or switch the polarity of the RF signal developed

at the IF output terminal, the switching rate being determined by

the local oscillator frequency.

(Ex. 1023 at 3:17-3:30 and Fig. 2 (emphasis added).) The voltage summing effect

of the transformer also satisfies the Patent Owner’s construction for “summer”

because the summer output (equivalent to (1,0,1,0,1…)*Vin + (0,1,0,1,0…)*-Vin)

represents the arithmetic sum of two signals—as shown in Dobrovolny Figure 3(c)

(Ex. 1023 at Fig. 3.)

Dobrovolny’s disclosure confirms that the summed output of trifilar

transformer 14, represented by the waveform in Figure 3(c), contains “a

multiplicity of harmonics,” which satisfies the “combined plurality of harmonics”

aspect of this claim element. (Ex. 1023 at 3:37-40.) Additionally, Maas teaches

that the choice to transmit at a harmonic frequency instead of the fundamental

frequency was a known design alternative that would have been obvious to one of


43

ordinary skill in the art. (Ex. 1010 at 25 (“In these cases, it may be wise to use a

mixer that is pumped at half the LO frequency, and to mix the RF signal with the

second harmonic of the junction’s conductance waveform.”).) It would therefore

be obvious to a person of ordinary skill in the art to transmit at a harmonic instead

of at the fundamental frequency. (Ex. 1002 at ¶ 240.)

d. Dobrovolny renders obvious element [1d]


Dobrovolny renders this limitation obvious by teaching that “[i]t will be

understood that waveform C includes a multiplicity of harmonics, including the

desired IF output frequency which may be derived by suitable filtering.” (Ex.

1023 at 3:37-40 (emphasis added).) It would be obvious to a person of ordinary

skill in the art how to “suitably filter” the IF output to select the harmonic

containing the “desired IF output frequency.” (Ex. 1002 at ¶ 254.) Maas’s

Microwave Mixers confirms that it “is generally easy” to filter out the desired

output. (Ex. 1010 at 9-10 (“Again, it is generally easy to filter out the desired

difference frequency.”).) In Maas’s discussion of the design of subharmonic

mixers, Maas further notes that it is “rarely difficult to realize” filters for isolating

the desired output of a subharmonic mixer. (Ex. 1010 at 26.) As Dobrovolny

teaches and Maas confirms, filtering the output signal of a mixer required no more


44

than applying known techniques using known devices to yield predictable results.

MPEP § 2143(d). (Ex. 1002 at ¶ 254.)

2. Claim 18

a. Dobrovolny discloses the preamble [18]


Claim element [18] is identical to claim element [1] discussed above. This

element is disclosed by Dobrovolny for the reasons discussed in Section

IX(A)(1)(a) at page 21 above.

b. Dobrovolny and Maas render obvious elements [18a] and [18b]

[18a] a first switch module to receive a first oscillating signal and a first bias signal, wherein said first oscillating signal causes said first switch module to gate said first bias signal and thereby generate a first periodic signal having a first plurality of harmonics, said first periodic signal having an amplitude that is a function of said first bias signal, said first bias signal being a function of a first information signal;

[18b] a second switch module to receive a second oscillating signal and a second bias signal, wherein said second oscillating signal causes said second switch module to gate said second bias signal and thereby generate a second periodic signal having a second plurality of harmonics, said second periodic signal having an amplitude that is a function of said second bias signal, said second bias signal being a function of a second information signal;

Claim elements [18a] and [18b] are substantively identical to claim elements

[1a] and [1b] discussed above, except for the last clause which recites “said [first] /

[second] bias signal being a function of a first information signal.” All but the


45

final sub-element of [18a] and [18b] are therefore rendered obvious by the

teachings of Dobrovolny in light of Maas for the reasons discussed in Section

IX(A)(1)(b) beginning at page 22 above. Dobrovolny also discloses the final sub-

element in [18a] and [18b].

(1) Claim element 18(a)(i) “said first bias signal being a function of a first information signal” and 18(b)(i) “said second bias signal being a function of a second information signal”

Dobrovolny discloses first/second bias signals that are a function of first

/second information signals. The ʼ940 patent explains that “[i]t is well known to

those skilled in the relevant art(s) that the information signal 5650 may be used as

the bias/reference signal 5646 directly without being summed with a bias signal.”

(Ex. 1001 at 57:1-4 (emphasis added).) In other words, the ʼ940 patent defines

“bias signal” as encompassing information signals. As explained in Section

IX(A)(1)(b)(3) above, Dobrovolny discloses symmetrical RF In signals that

constitute first and second bias signals because they contain information in the

form of television programming. (Ex. 1023 at 1:14-17.) All persons of skill in the

art understand that the RF In signals disclosed in Dobrovolny are the signals that

contain the information to be received or transmitted. (Ex. 1022 at 36.)

The specification of the ‘940 patent emphasizes that “[i]t is well known to

those skilled in the relevant art(s) that the information signal 5650 may be used as

the bias/reference signal 5646 directly without being summed with a bias signal.”


46

(Ex. 1001 at 57:1-4.) In RF circuits like Dobrovolny’s in which the information

signal is “used as the bias/reference signal … directly without being summed

with a bias signal” the “bias signal” is necessarily a function of the information

signal. (Ex. 1001 at 57:1-4; Ex. 1002 at ¶ 260-263, 268-271 (emphasis added).)

c. Dobrovolny discloses element [18c]


Claim element [18c] is identical to claim element [1c]. Accordingly, claim

element [18c] is obvious in view of Dobrovolny for the reasons discussed in

Section IX(A)(1)(c) on page 40.

d. Dobrovolny renders obvious element [18d]


Claim element [18d] is identical to claim element [1d]. Accordingly, claim

element [18d] is obvious in view of Dobrovolny for the reasons discussed in

Section IX(A)(1)(d) on page 43.

3. Claims 94 and 264


[264] The apparatus of claim 18, wherein said first plurality of harmonics are


47

harmonics of the fundamental frequency of said first periodic signal and said second plurality of harmonics are harmonics of the fundamental frequency of said second periodic signal.

The teachings of Dobrovolny in light of Maas render claims 94 and 264

obvious. Dobrovolny teaches that the output of the single-balanced mixer disclosed

in Figures 1 and 2 “includes a multiplicity of harmonics, including the desired IF

output frequency which may be derived by suitable filtering.” (Ex. 1023 at 3:31-

40.) Maas teaches that, as a matter of physics, harmonics are present in the mixer

output. Maas explains that mixer output frequencies can be calculated using the

relation:

fIF = mfRF + nfLO

where

m, n = 0, ±1, ±2,…

And fIF, fRF, and fLO are the IF, RF, and LO frequencies.

(Ex. 1010 at 24.) The following calculations, which apply Maas’s relation, confirm

that Dobrovolny’s mixer generates the harmonics recited in the claim:

Assume RF = 10, LO = 5, and mixing at n, m = 1, 3, 5:

At m,n = 1, the sum frequency fIF = (1*10) + (1*5) = 15




48

(Ex. 1002 at ¶¶ 287-291.) The calculation in the first bullet above shows the sum

frequency mixer output (i.e., 15) at fundamental frequency mixing (i.e., m,n=1).

The third and fifth harmonics of this periodic signal output by the mixer (i.e., 45

and 75) are also present in the mixer output. It would be obvious to a person of

ordinary skill in the art to operate Dobrovolny’s mixer at frequencies that would

generate these harmonics of the fundamental frequency of the first and second

periodic signals for each of the reasons discussed in claim 1(a)(v) in Section

IX(A)(1)(b)(5) beginning on page 34, above.

4. Claims 81, 82, 83, 84, 88, 89, 90, 91, 251, 252, 253, 254, 258, 259, 260, and 261

[81] The apparatus of claim 1, wherein said first switch module is a electronic device.

[88] The apparatus of claim 1, wherein said second switch module is a electronic device.

[251] The apparatus of claim 18, wherein said first switch module is an electronic device.

[258] The apparatus of claim 18, wherein said second switch module is an electronic device.






49









This claim group features incrementally narrower claim sets requiring the

switch modules to be (1) electronic devices, (2) semiconductor devices, (3)

transistors, and (4) field effect transistors. Any device that satisfies the last claim

set reciting switch modules that are field effect transistors necessarily satisfies

every other claim in the group.

Dobrovolny’s disclosure of switch modules that are GaAs MESFET devices

such as NEC MESFETS NE72084 satisfies every element in the claim group. (Ex.

1023 at 2:61-66.) Gallium Arsenide MESFETS are electronic devices that include

source, gate, and drain electrodes. (Ex. 1023 at 2:61-66.) Persons of ordinary skill

in the art understand that a GaAS MESFET is a semiconductor field-effect


50

transistor. (Ex. 1010 at 15-23 (“GaAs MESFET” means “Gallium Arsenide metal

semiconductor field-effect transistor (MESFET);” “The GaAs MESFET is a

junction field-effect transistor (JFET).”; Ex. 1002 at ¶ 283.)

B. Ground 2 – Dobrovolny in light of Maas and Sullivan Render Claims 86, 93, 256, and 263 Obvious Under 35 U.S.C. § 103(a)





Claims 86, 93, 256 and 263 are obvious in light of the teachings of

Dobrovolny combined with Maas and Patrick J. Sullivan, et al., Active Doubly

Balanced Mixers for CMDS RFIC's. The teachings of Dobrovolny and Maas

disclose each structure recited in independent claims 1 and 18 from which these

claims depend. Dobrovolny discloses a mixer that uses MESFET switches. (Ex.

1023 at 2:60-64.) Sullivan teaches that, “[t]he similarities between MOSFET and

MESFET devices allow the designer to apply the extensive knowledge of

MESFET mixers to the design of MOSFET mixers.” (Ex.1005 at 1.) And Sullivan

explains that he successfully built CMOS-FET mixers: “Two fully integrated

doubly balanced CMOS mixers have demonstrated the ability of a standard CMOS


51

process to operate at commercial wireless frequency bands with reasonable

dynamic range. . . . The dynamic range and port-to-port isolation make doubly

balanced CMOS mixers suitable for downconverter and upconverter applications

in an all-CMOS transceiver.” (Ex. 1005 at 9.)

A person of ordinary skill would be motivated to combine the teachings of

Dobrovolny and Sullivan to use CMOS-FET switches in a mixer like

Dobrovolny’s. (MPEP § 2143(g); Ex. 1002 at ¶¶ 285-286). Sullivan provides a

suggestion and motivation for combining its teachings with Dobrovolny’s by

explaining that existing CMOS infrastructure supported the development of low

cost, mast-produced integrated circuits:

Using CMOS technology, RF designers can utilize the large

infrastructure in place that supports and develops low cost, mass-

produced ICs. The drive to increase transceiver integration and reduce

transceiver cost makes CMOS an attractive technology for low cost,

highly integrated transceivers.

(Ex. 1005 at 9.) Sullivan’s teachings would have led one of ordinary skill to

modify Dobrovolny’s teachings to utilize CMOS-FET switches because Sullivan

teaches that CMOS-FET switches are “an attractive technology” alternative to

MESFETs for designers seeking to build “low cost, highly integrated transceivers.”

(Ex. 1002 at ¶ 286.) All commercial RF circuit designers sought to build “low cost,

highly integrated transceivers” because integration and cost reduction are two main


52

drivers of electronic circuit designs. (Ex. 1022 at 7-8 (“in addition, digital

communications techniques can exploit the relentless advance of digital integrated

circuit (IC) technology to realize improved functionality at lower power dissipation

and lower cost.”).)

C. No Secondary Considerations of Non-Obviousness Exist

Petitioners are unaware of any objective evidence of non-obviousness of the

Petitioned Claims. Petitioners respectfully reserve the right to rebut any alleged

evidence of non-obviousness identified in Patent Owner’s Response.

X. CONCLUSION

Petitioners respectfully request institution of inter partes review of claim 1

and its dependent claims 81-84, 86, 88-91, 93, and 94, and claim 18 and its

dependent claims 251-54, 256, 258-61, 263, and 264 of the ’940 patent, and a

finding that the claims are unpatentable as obvious under 35 U.S.C. § 103(a).


53

Dated: August 28, 2015 COOLEY LLP ATTN: Patent Group 1299 Pennsylvania Ave., NW, Suite 700 Washington, DC 20004 Tel: (703) 456-8000 Fax: (202) 842-7899

Respectfully submitted, COOLEY LLP

By: /Timothy S. Teter/ Timothy S. Teter Reg. No. 47,134


54

CERTIFICATE OF SERVICE

Pursuant to 37 C.F.R. §§ 42.6(e) and 42.105(b), the undersigned certifies

that on August 28, 2015, a complete and entire copy of this Petition for Inter

Partes Review of Patent No. 6,091,940, including Exhibit Nos. 1001-1035 and a

Power of Attorney, was served via FEDERAL EXPRESS, costs prepaid, to the

Patent Owner by serving the correspondence address of record as follows:

Workman Nydegger 60 East South Temple, Suite 1000 Salt Lake City, UT 84111 Counsel of Record for Patent Owner Parkervision, Inc.

and, upon counsel of record for the Patent Owner in the litigation pending before

the U.S. District Court for the Middle District of Florida entitled ParkerVision, Inc.

v. Qualcomm Incorporated, et al., No. 6:14-cv-00687-PGB-KRS (M.D. Fla.) as

follows:

Douglas Aaron Cawley Richard Kamprath McKool Smith, PC 300 Crescent Court, Suite 1500 Dallas, TX 75201 Attorneys for Plaintiff ParkerVision, Inc.

Jennifer A. Albert Joshua W. Budwin Kevin L. Burgess Mario A. Apreotesi Leah Buratti Kathi Li Puneet Kohli McKool Smith, PC 300 West 6th Street, Suite 1700 Austin, TX 78701 Attorneys for Plaintiff ParkerVision, Inc.


55

James Arthur Bolling Stephen D. Busey Smith, Hulsey & Busey 225 Water Street, Suite 1800 PO Box 53315 Jacksonville, FL 32202-3315 Attorneys for Plaintiff ParkerVision, Inc.

Dated: August 28, 2015

COOLEY LLP ATTN: Timothy S. Teter Patent Docketing 1299 Pennsylvania Ave. NW, Suite 700 Washington, D.C. 20004 Tel: (650) 843-5000 Fax: (202) 842-7899

/Timothy S. Teter/ Timothy S. Teter Reg. No. 47,134

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