5G Millimeter‐Wave Radio Technology

Gabriel M. RebeizDistinguished Professor at the University of CaliforniaWireless Communications Industry Endowed Chair

ECE DepartmentUniversity of California, San Diego

Tel: 858‐336‐3186rebeiz@ece.ucsd.edu

Qualcomm/Ericsson 5G North American Workshop

2

WE BUILD STUFF !!!

3

Rebeiz Group: Phased Arrays and Transceivers

24 GHz CMOS Rx phased array35 GHz SiGe T-Rx phased array

80 GHz 16-element phased-array with built-in-self-test (R&D100 Award, Microwave Prize). 150 GHz CMOS T/Rx with 20 Gbps

Wafer-scale phased arrays with integrated antennas

4

US‐NAVY Radar/Communication Phased Arrays

•$250/element using all GaAs components. • Reduced to $25/element using SiGe!!

6” high

5

2.5” high

New Generation of Phased Arrays using CMOS/SiGe

2001 briefing inside Boeing

Isotropic Phone Antenna and 10 dB Base Station Antenna

Pin: 10 WPin: 1 WPin: 0.1 W

● : 30 GHz▲: 60 GHz

Pr = - 65 dBm for 1 Gbps (16 QAM)(250 MHz BW, 15 dB S/N, 7 dB NF)

6

4x4 Array on Phone (15 dB) and 23 dB Base Station Antenna

Pin: 10 WPin: 1 WPin: 0.1 W

● : 30 GHz▲: 60 GHz

4x4 array(26o bw)

8x8 array(13o bw)

Now, we are talking!! But we need beam steering.Note that PA needs to be 5-6 dB higher power due to backoff.

7

4x4 Array on Phone (15 dB) and 33 dB Base Station Antenna

Pin: 10 WPin: 1 WPin: 0.1 W

● : 30 GHz▲: 60 GHz 4x4 array

(26o bw)

16x32 array(6o bw)

We really need beam-steering!!Note that PA needs to be 5-6 dB higher power due to backoff.

8

9

Do not be afraid

(from mm-wave hardware)

Just spend money (please)

RF Beamforming or Digital (MIMO) Beamforming?

• One scanning beam (or 2)• Single transceiver• Low power • Great for user terminals

• Multiple beams• Full receiver on every

antenna element• Power hog at high data rates• Good for base-stations

10

11

Broadcom 16Tx/16Rx 60 GHz Phased Array (40 nm CMOS)

12

Broadcom 16Tx/16Rx 60 GHz Phased Array (40 nm CMOS)

13

Broadcom: 10 Gbps Millimeter Wave SoC (Baseband/Modem) Targets Wireless Backhaul and Fronthaul Applications

• 10Gbps (!!)• Modulation up to 256QAM • Wide channels up to 2 GHz • Integrated wideband Analog Front

End (AFE) • Supports Fast HW Design • Advanced, wideband IQ impairment

correction mechanism

TensorCom 60 GHz link (7 Gbit/sec at 3m)

14

• Developed in a small company• Single SOC (150 mW)

15

Millimeter‐Wave (77 GHz) Automotive Radars (>1M/year)

They know what they want and build it in millions of units/year

Antenna Directivity: 30 dB

77 GHz 16-Element Phased Array with BIST

DC/ control pins

IF pins Bias, others

165x5.5 mm2

Measurements at 79-81 GHz (Scanning to +/-50o)

• Beam steering obtained for 100° field of view.

• Average sidelobe level < -17 dB up to 40o.

Beam 0° 12° 21o 32o 40o 48o

HPBW 5.5o 5.5o 6.0o 6.3o 7.0o 9.6o

17

Measurements: 79 GHz Automotive Radar with phased array beam scanning

• Scan picture of car with door closed and door open.

Door Open

Door

No Door

Door Closed

(Car is ~25 meters from radar)

18

6x10 cm2

19

Wafer-Scale Phased Arrays

• High-efficiency antenna layer• Scalable up to 12(in)• First developed at UCSD

Silicon wafer

Antenna layer(e.g. Quartz)

Phased arrayelement

Trx/Baseband

6x6 mm2

20

Do be afraid

(from rain!!!)

It will reduce your data rate!!

Rain attenuation dB/km

21

6-12 dB/km for medium to heavy rain (70-80 GHz)

2-4 dB/km for medium to heavy rain (28 GHz) 55-60 dB

antenna gain

Alternative Solution: Beam Scanning with a Multi-Focal Lens

Single beam with switch or multiple beams with a transceiver on every antenna

22

231.7‐2.5 GHz Tunable Filters and  channelizers

500‐700 MHz tunable notch filter

Rebeiz Group: Antennas and Tunable/Cognitive Wireless Communications

DVC1DVC2 DVC3

DVC4

0 1 cm

0.7-2.2 GHz tunable antennas with 20 dB isolation between ports

Conclusion

Millimeter‐wave hardware is expensive in NRE, but can do be done in large numbers and then low cost CMOS, SiGe, GaAs pHEMT, GaN, packaging, antennas, etc. … are available. Not many people/groups know this stuff. This is not easy. Design techniques are getting better, but there is still (and will always be) some voodoo in RF  Just figure out what you want first!!

24