ECEN5553 Telecom SystemsDr. George ScheetsWeek #14 &15
[31] "Mobile's Millimeter Wave Makeover"[32] "Emerging Technologies and Challenges
for 5G Wireless"[33a] "Dish Network for the Enterprise"[33b] "The Picturephone is Here. Really."[35a] "The Broadcast Empire Strikes Back"[35b] "Netflix Factor has University Networks Creaking"Final ExamFinal Exam
Live: 10:00 – 11:50 AM, Monday, 8 DecemberLive: 10:00 – 11:50 AM, Monday, 8 DecemberDL: Not Later than Monday, 15 DecemberDL: Not Later than Monday, 15 December
ECEN5553 Telecom SystemsDr. George ScheetsWeek #14 &15
[31] "Mobile's Millimeter Wave Makeover"[32] "Emerging Technologies and Challenges
for 5G Wireless"[33a] "Dish Network for the Enterprise"[33b] "The Picturephone is Here. Really."[35a] "The Broadcast Empire Strikes Back"[35b] "Netflix Factor has University Networks Creaking"Final ExamFinal Exam
Live: 10:00 – 11:50 AM, Monday, 8 DecemberLive: 10:00 – 11:50 AM, Monday, 8 DecemberDL: Not Later than Monday, 15 DecemberDL: Not Later than Monday, 15 December
Data Rate Roll-OffData Rate Roll-Off
Signal power decrease is proportional toSignal power decrease is proportional to1 / (distance)1 / (distance)22
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4G Wireless (MAN)4G Wireless (MAN) Long Term Evolution (LTE)Long Term Evolution (LTE)
OFDM, MIMO, Data Rates OFDM, MIMO, Data Rates >> 60 Mbps 60 Mbps Back to the Future: TDMA → CDMA → TDMABack to the Future: TDMA → CDMA → TDMA Initially Deployed in 2011. Initially Deployed in 2011.
LTE-AdvancedLTE-Advanced Seeing initial deployment in 2013Seeing initial deployment in 2013 1-2 Gbps speeds claimed on downlink1-2 Gbps speeds claimed on downlink Some Trade Pub articles → Don't need a LANSome Trade Pub articles → Don't need a LAN
Speeds ↓ as distance from BS ↑ & BW sharedSpeeds ↓ as distance from BS ↑ & BW shared
WiMax (IEEE 802.16)WiMax (IEEE 802.16) OFDM, MIMO, Data Rates OFDM, MIMO, Data Rates << 10 - 70 Mbps 10 - 70 Mbps Deployed by Sprint & Clearwire. Sprint moved to LTE. Deployed by Sprint & Clearwire. Sprint moved to LTE. Alternative to LTE? No. Used as back haul, fixed wireless. Alternative to LTE? No. Used as back haul, fixed wireless.
5G Cellular5G Cellular IP Wireless TrafficIP Wireless Traffic
3 Exabytes in 2010 (exabyte = 103 Exabytes in 2010 (exabyte = 101818)) Projected to exceed 500 exabytes by 2020Projected to exceed 500 exabytes by 2020 4G Cannot Handle4G Cannot Handle
Goals Goals Aggregate Data Rate (bps/unit area) 4G x 1000Aggregate Data Rate (bps/unit area) 4G x 1000 Edge Rate (Worst Case speed seen by 5%)Edge Rate (Worst Case speed seen by 5%)
1 Mbps → 100 Mbps1 Mbps → 100 Mbps Average Round Trip Time: Reduce by x 15Average Round Trip Time: Reduce by x 15 Energy Use: Don't Let It Increase Energy Use: Don't Let It Increase
source: Andrews, J;, et al, "What Will 5G Be?", IEEE Journal on Selected Areas in Communications, June 2014
Meeting 5G GoalsMeeting 5G Goals Extreme DensificationExtreme Densification Mix of few large cells and Mix of few large cells and manymany small cells small cells
Including pico cells (range < 100 meters)Including pico cells (range < 100 meters) Including femto cells (< 10 – 20 meters)Including femto cells (< 10 – 20 meters) Highest Bit Rates from Smallest CellsHighest Bit Rates from Smallest Cells
Increasing # of protocolsIncreasing # of protocols Smart RadiosSmart Radios
Improved Mobility SupportImproved Mobility Support Smart NetworkSmart Network Seamless Merging of Large & Small CellsSeamless Merging of Large & Small Cells
source: Andrews, J;, et al, "What Will 5G Be?", IEEE Journal on Selected Areas in Communications, June 2014
Meeting 5G GoalsMeeting 5G Goals Increased BandwidthIncreased Bandwidth "Beach Front" BW is taken"Beach Front" BW is taken
XXX MHz and X GHzXXX MHz and X GHz Propagates and Penetrates Reasonably WellPropagates and Penetrates Reasonably Well
Must go to Higher Carrier FrequenciesMust go to Higher Carrier Frequencies mmWave Frequencies XX to XXX GHzmmWave Frequencies XX to XXX GHz
Do Not Propagate as WellDo Not Propagate as Well Electronics Not So Good & ExpensiveElectronics Not So Good & Expensive
mmWave Not So Good for Large CellsmmWave Not So Good for Large Cells Potentially Good for Femto & Pico CellsPotentially Good for Femto & Pico Cells
Meeting 5G GoalsMeeting 5G Goals Increased Spectral Efficiency (bps per Hz)Increased Spectral Efficiency (bps per Hz)
Massive MIMOMassive MIMO Including 3D BeamformingIncluding 3D Beamforming
Cloud Based Control?Cloud Based Control? BackhaulBackhaul
Fiber Deployments ContinueFiber Deployments Continue Wireless Point-to-Point Speeds ImprovingWireless Point-to-Point Speeds Improving
mmWave more feasible for static outdoor linksmmWave more feasible for static outdoor links
Localized Caching of High BW Video Localized Caching of High BW Video
source: Andrews, J;, et al, "What Will 5G Be?", IEEE Journal on Selected Areas in Communications, June 2014
IEEE 802.11 ComparisonIEEE 802.11 Comparison
Source: "IEEE 802.11ac: From Channelization to Multi-User MIMO", IEEE Communications Magazine, October 2013
WiFi Speed vs. DistanceWiFi Speed vs. Distanceso
urc
e: 1
3 M
ay 2
002
Net
wor
k W
orld
802.11 Flow Chart (Simplified)802.11 Flow Chart (Simplified)
Packet to Send?
ACKreceived?
No
Yes
No
YesNo
Binary ExponentialBack-off Used(Similar to 802.3)Min Wait: 0Max Wait: 51.2 msec
Back-off
Media Quiet?
Media Quiet?
Yes
Transmit
NoQuiet
for IFS?Yes
No
INMARSAT PhonesINMARSAT Phones
Recently smallerphones have become
available for usewith latest satellites.
Parabolic AntennasParabolic Antennas
Geosynchronous Satellite vs Sun, Mid-day, Northern Hemisphere
Geosynchronous Satellite vs Sun, Mid-day, Northern Hemisphere
x
WinterSun is belowsatelliteorbital plane.
x
Fall Sun → sameplane assatellite.
x
Spring Sun→ sameplane asSatellite.
x
SummerSun is abovesatelliteorbital plane.
2013 Fall Sun Outage, Microspace's AMC-12013 Fall Sun Outage, Microspace's AMC-1
Source: www.ses.com/4551568/sun-outage-data
x
Market Split for Backhaul GearMarket Split for Backhaul Gear
Source: "High-Capacity Ethernet Backhaul Radio Systems for Advanced Mobile Data Networks", IEEE Microwave Magazine, August 2009.
Cell Towerwith
Point-to-Point RF link
Cell Towerwith
Point-to-Point RF link
ProtocolsProtocols ProprietaryProprietary 802.16802.16 802.11802.11
Free Space LasersFree Space Lasers
Sources: www.fsona.comwww.engadget.com/media/2006/02/gigabeam.jpg
Comparison: Optical vs RF BackhaulComparison: Optical vs RF Backhaul
Source:"The Next Challenge for Cellular Networks: Backhaul", IEEE Microwave Magazine, August 2009 .
194,000 GHz XX GHz
5.3 minutes downtime/year
8.8 hours downtime/year
Hughes Net (2013)Hughes Net (2013)
IridiumIridium
6 Low Earth orbits, 11 satellites per polar orbit
Not-so-miniature phone.image sources: Wikipedia& www.iridium.com
Iridium in AntarcticaIridium in Antarctica
Source: wikipedia
1
2 34
5
7
6
8
GlobalstarGlobalstar
image source: www.globalstar.com
The TCom Systems final is in three weeks Chief. I need some time off to study. Dick
TracywithWristRadio
DickTracywithWristRadio
Image Source:Wikipedia
You too could have had a Wrist RadioYou too could have had a Wrist Radio
Touchscreen GSM Cell Phone/
PDA/ Wristwatch
formerlyavailable at
www.thinkgeek.com
Stick-on Smart PhoneStick-on Smart Phone
NTSC TVNTSC TV Analog video Analog video
Obsolete as of June 2009Obsolete as of June 2009 30 frames/second30 frames/second 525 Scan Lines in a Frame, 525 Scan Lines in a Frame, ≈ ≈ 485 Active485 Active Resolution ≈ 640 x 480 pixelsResolution ≈ 640 x 480 pixels Video Bandwidth 4.2 MHzVideo Bandwidth 4.2 MHz RF Bandwidth 6.0 MHzRF Bandwidth 6.0 MHz
AM modulated VideoAM modulated VideoFM Modulated VoiceFM Modulated VoiceGuard BandGuard Band
Red, Green, & Blue used on MonitorsRed, Green, & Blue used on Monitors
Color VideoColor Video
Ele
ctro
nic
s
3 Pick-Up Elements
CCD’s
R
G
B
Camera
Ele
ctro
nic
s R
G
B
3 drivesignals
Monitor
Receiver electronics generate 3 signals withstrength proportional to light falling on the 3 camera pick-up elements.
Paints are SubtractivePaints are Subtractive
24 bit color 224 = 16.78 M colors24 bit color 224 = 16.78 M colors
256 Colors256 Colors
16 Colors16 Colors
MPEG Employs...MPEG Employs... Motion Estimation Algorithms
Tracks groups of NxN pixels... ...imperfectly if small and fast moving
Discrete Cosine Transforms Maps NxN pixel block spatial characteristics to
frequency domain Values Quantized
Some high frequency components zero'd out Gets rid of very fine detail Other values rounded off Causes some distortion (smearing)
Example of High Frequency FilteringExample of High Frequency Filtering
0 20 40 60 80 100 120 140
0
22
1
1270 i
Scan Line (Time Domain)
Monitor Image
FilteringFiltering
0 10 20 30 40 50 60 700
2
44
Xj
640 j
Scan Line (Frequency Domain)
Scan Line (Frequency Domain after zeroing)
0 10 20 30 40 50 60 700
2
44
0
Yj
640 j
1/2 the points thrown out (values < .1)
FilteringFilteringReconstructed Scan Lines (Time Domain after filtering)
0 20 40 60 80 100 120 1401
0
1
22
0.086
yi
1270 i
y
Monitor Image
Using NxNpixel blockslocalizesdistortion to NxN area,unlike thisexample.
Note Edges Aren't As SharpNote Edges Aren't As Sharp
y
Compare
Dick Tracy with Wrist RadioDick Tracy with Wrist RadioThis is a small JPEG imagethat's been enlarged.
With a good contrast monitor, you should be able to see evidence of theblocks, and should alsonote that the distortion tends to be localized to areas where the picture is changing.
JPEG DistortionJPEG Distortion
Note the fuzzygray 'cloud'.
MPEG Employs...MPEG Employs... Huffman Coding
Used to map DCT results to a bit streamUses unequal length code wordsHigh probability outputs get shorter words G.711: equal length code words (8 bits/sample) Morse Code: unequal length
Morse Code:An UnequalLength Code
Average bit rate is < fixed length code= 5 bits/character for the alphabet,
or 6 bits/characterfor alphabet &
numbers 0-9
Morse Code:An UnequalLength Code
Average bit rate is < fixed length code= 5 bits/character for the alphabet,
or 6 bits/characterfor alphabet &
numbers 0-9
Image Source: Wikipedia
Huffman CoderUnequal Length Code Words
High Probability? Assign Small Word.
Huffman CoderUnequal Length Code Words
High Probability? Assign Small Word. Suppose have 4 voltages to move:Suppose have 4 voltages to move:
-3 v-3 v 25%25%-1 v-1 v 5% 5%+1 v+1 v 40%40%+3 v+3 v 30%30%
2 bit code word11100001
Huffman Code111110
010
1,000,000 voltages/sec → 2,000,000 bps (2 bit code)1,000,000 voltages/sec → 1,900,000 bps (Huffman)
.25(3) +.05(3) + .40(1) + .30(2) = 1.9 bits/word on averageUniquely Decodable: 1110010110 = ?
MPEG Video Frame SequenceMPEG Video Frame Sequence1/30th second
Intrapictures (JPEG Still)
Bi-directional PicturesMostly
Motion EstimationTechniques
Predicted PicturesMostly changesince previousI or P frame
MPEG 1MPEG 1 Standard since 1992 Compression of motion video & audio at about 1.5
Mbps (VHS Quality < NTSC) Targeted at digital playback & storage Has Random Access capabilities Somewhat Obsolete
Divides picture up into 8x8 pixel blocksConverts blocks to bit stream
MPEG 2MPEG 2 Targets higher quality compression,
typically at 3-6 Mbps bit rates Being used for Direct Broadcast TV Large chunks of MPEG2 used in
U.S. HDTV standard Standard since 1994
MP3 MP3 Web audio clipsWeb audio clips Uses audio compression from MPEG 1Uses audio compression from MPEG 1
12-1 typical compression ratio12-1 typical compression ratio
MPEG 4MPEG 4
Aimed at Multimedia Coding Bit rates from 8 Kbps - 40+ Mbps Can codes objects as opposed to NxN blocks
Ability to interact & manipulate objects Standard in 1999 Used in Quicktime 6, Direct TV
H.261, H.263, & H.264H.261, H.263, & H.264 Target real time videoconferencing Subset of MPEG Wide variety of bit rates
64 Kbps - 128 Kbps: Face shot (video phone)384 Kbps: considered to be minimum speed for decent full
screen videoconferencing New OSU gear is using H.263/4 @ 1.92 Mbps
H.264 quality > H.263 > H.261Newer protocols require more processing powerH.261 less common today
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