Emerging Wireless Standards Wireless Summer School June 4

Emerging Wireless Standards Wireless Summer School June 4, 2008 Session A 1 1: 30 -5: 15 PM James Neel james. neel@crtwireless. com (540) 230 -6012 www. crtwireless. com Jeff Reed reedjh@vt. edu (540) 231 -2972 www. wireless. vt. edu

Presentation Overview Theory (32) OFDM and Antenna Array Theory Emerging Standards (24) Cellular and Wi. MAX (16) WLAN (10) WPAN (11) Cognitive Standards ( 7) Interoperability Standards ( 6) Summary and Trends Break & Poster Session 2: 45 -3: 30 http: //www. wisoa. net/members_logos/mobile_in ternet-big. jpg

Principles of Orthogonal Frequency Division Multiplexing and Multiple Input Multiple Output Communications Systems

Intersymbol Interference • Occurs when symbol period (Ts) is less than channel delay spread, • ISI introduces an error floor to BER Floor for various modulations – Limits maximum throughput • Solutions: – Equalization (high complexity) – Longer symbol periods (generally means lower data rate) QPSK limit J. C. -I. Chuang, "The Effects of Time Delay Spread on Portable Radio Communications Channels with Digital Modulation, " IEEE JSAC, June 1987

Multicarrier communications: Longer period, same data rate • Concept: –Divide original data stream at rate R into L lower rate (R/L) streams on different carriers to increase symbol time • Long history –KINEPLEX –ANDEFT –KATHRYN • Effects –High receiver complexity J. Andrews, A. Ghosh, R. Muhamed, Fundamentals of Wi. MAX, Prentice Hall, 2007 B/L • separate receiver chain per carrier –Bandwidth due to sidebands –Each subcarrier experiences flat fading Bc B f

OFDM • Much simpler to create multicarrier transmission using i. FFT – Information carried in magnitude and phase of each bin – Then can be recovered by using FFT at receiver • Ideal inverse Fourier transform of multicarrier would be infinite duration sine waves – Cut at Symbol duration Ts – Rectangular windowing causes sinc spectrum in frequency domain with zeros at 1/Ts – Orthogonal subcarriers

Guard intervals and intersymbol interference Guard interval OFDM Symbol Delay Spread • If we space OFDM symbols by gaps at least as long as the delay spread, then there will be no intersymbol interference • However, there will still be interference within the symbol (intrasymbol)

Equalization and the DFT • While using longer symbol timing means OFDM can avoid irreducible errors, still have interfering energy in band from multipath – Received signal is the (linear) convolution of channel impulse response with transmitted signal • DFT Circular Convolution Theorem – Circular convolution of two discrete vectors in time domain – Is multiplication in the frequency domain • Implication: If we can make the system behave like a circular convolution, equalization is trivial – complex multiplication per FFT bin at the receiver

Cyclic Prefix • Adding a cyclic prefix at transmitter leads to circular convolution • Note that misaligned timing still results in a circular convolution, just time shifted – Makes for phase shifts in FFT bins – Correct that in a moment J. Andrews, A. Ghosh, R. Muhamed, Fundamentals of Wi. MAX, Prentice Hall, 2007

Comments on Cyclic Prefix J. Andrews, A. Ghosh, R. Muhamed, Fundamentals of Wi. MAX, Prentice Hall, 2007 • We’re transmitting redundant bits (no information transfer) – Bandwidth penalty: L / (L + v) – Power penalty: L / (L + v) • Penalty becomes negligible as L becomes large (but there are tradeoffs! – more later) • Permits low complexity equalization for same data • Power penalty generally more rates important in practice where systems are interference limited • Single carrier tap# approximately bandwidth • Penalty can be avoided with delay product zero prefix –MAC • OFDM, number subcarriers grows with bandwidth-delay product, so – Nothing transmitted in guard band (zero prefix) – Receiver adds tail back to beginning of symbol – Used in Wi. Media

Frequency Errors • Primary sources of frequency errors – Doppler shift – Clock mismatches – Phase noise • Effects – Reduction in amplitude (missampling sinc) – Intercarrier interference O. Edfors, M. Sandell, J. van de Beek D. Landström, F. Sjöberg, “An Introduction to Orthogonal Frequency Division Multiplexing, ” Sep 98, Available online: http: //epubl. luth. se/avslutade/0347 -0881/96 -16/esb 96 rc. pdf

Effects of Frequency Errors • Comments – Impact greater for higher SNR signals – Note 5% estimation error can lead to 5 d. B effective degradation at 64 -QAM like SNRs – Big frequency impact is why OFDM was originally for fixed deployments • Techniques – Data aided – Non data aided – Cyclic prefix O. Edfors, M. Sandell, J. van de Beek D. Landström, F. Sjöberg, “An Introduction to Orthogonal Frequency Division Multiplexing, ” Sep 98, Available online: http: //epubl. luth. se/avslutade/0347 -0881/96 -16/esb 96 rc. pdf Fading Channel AWGN

Channel Estimation • Channel assumed static for duration of symbol, though frequency/phase varying over bandwidth • Solution, embed pilot symbols at regular intervals in the symbol – Used closest pilot – Interpolate From IEEE Std 802. 16 -2004

Peak-to-Average Power Ratio • Sum of large number of (somewhat) independent subcarriers leads to signal distribution that is somewhat Gaussian • Implications – long tails for amplitude distribution PAPR CDF for Varying # Subcarriers – Possibly large ratios of peak-topower ratios • Long tails can drive amplifiers into nonlinear region – Introduces harmonics and significant out-of-band spectral energy

Solution Techniques Spectral Effects of Windowing and Clipping • Clipping – Eliminate signals above a certain level or ratio • Peak windowing – Filter peaks • Linear block code – Select only those codewords with small PAPR – Can also provide error correction • Peak Cancellation – Subtract signals from high peaks – Need to be similar bandwidth to limit out-of-band interfernce • Symbol Scrambling Peak Cancellation, Clipping, PAPR = 4 d. B

Adaptive Modulation • Different subcarriers experience different flat fades • Means different SINR • Adapting modulation scheme of each subcarrier to its SINR allows the system to approach Shannon capacity J. Andrews, A. Ghosh, R. Muhamed, Fundamentals of Wi. MAX, Prentice Hall, 2007 B/L Bc B f

OFDMA • Multiple user access with OFDM • Lots of flexibility possible when splitting up OFDM symbols and frames • Allocation algorithms – Maximum Sum Rate – Proportional fairness – Proportional rates constraints – Assign different subcarriers to different users – Assign different time slots to different users – Vary modulation and coding – Vary powers – More options available with antenna arrays J. Andrews, A. Ghosh, R. Muhamed, Fundamentals of Wi. MAX, Prentice Hall, 2007

OFDM Summary • OFDM overcomes even severe intersymbol interference through the use of the IFFT and a cyclic prefix. • Limiting factor is frequency offset – Correctable via simple algorithm when preambles used • Two key details of OFDM implementation are synchronization and management of the peak-toaverage ratio. • OFDMA provides a lot of flexibility to a system’s resource allocation – Permits exploitation of multi-user diversity

Antenna Array Algorithms and MIMO

Antenna Array Principles • Exploit multiple independent channels created by multipath diversity • Works with uncorrelated antennas –Array gain • Coherently combine energy from antennas • Works even with perfectly correlated antennas as received SNR increases linearly with the number of receive antennas 10 Fading Envelopes [d. B] • The use of multiple antennas provide two forms of diversity: –Diversity gain 5 0 -5 -10 0 200 400 600 Samples 800 • Adding additional transceiver chains is expensive (SWAP and cost), but can provide tremendous (though competing) gains – – Increase the system reliability (decrease the bit or packet error rate) Increase the achievable data rate and hence system capacity Increase the coverage area Decrease the required transmit power 1000

Receive Diversity • Oldest and simplest diversity technique • Receiver leverages independence of fades on antennas Selection Diversity – Selection Combining (SC) • Choose antenna with maximum SINR • Lowest complexity – Equal Gain Combining (EGC) – Maximum Ratio Combining (MRC) • Weight signals by SINR • Best performance (system SINR is sum of antenna SINRs) MRC SNR (d. B) • Phase align and sum signals across antennas Average SNR Improvements EGC SC Antennas

Open Loop Transmit Diversity (1/2) • Transmitter sends multiple signals (possibly copies) – These interfere at the receiver, but if coded properly, the receiver can recover the signal • Simplest implementation is orthogonal space time block codes or Alamouti codes 1 – Assumes flat constant channel over two symbol periods (may not be true for high mobility) – Requires channel knowledge at receiver – No change in rate required h 1 TX Encoder h 2 RX Decoder • Receiver Alamouti Operation • Output SNR 2 x 1 Alamouti 1. S. M. Alamouti, “A simple transmit diversity technique for wireless communications, ” IEEE Journal on Selected Areas in Communications, vol 16 pp. 1451– 1458, Oct 1998

Open Loop Transmit Diversity (2/2) A 4 x 2 Stacked Alamouti System • 2 x 2 STBC (same transmit encoder) SINR – Note number of h terms maximized when Nt = Nr for a fixed number of antennas – Also full-diversity, orthogonal STBCs exist only for certain combinations of Nt and Nr. • Can also use space-time trellis codes for added 1 -2 d. B, but those have exponential complexity order J. Andrews, A. Ghosh, R. Muhamed, Fundamentals of Wi. MAX, Prentice Hall, 2007 Comparison of STBC and MRC

Space-Time Trellis Coding • Convolutional code applied to space and time domain • Each antenna output is mapped into modulation symbol • Maximum likelihood sequence estimator ( Viterbi algorithm) Example) Delay Diversity (by Wittneben [4]) Encoder structure for two antennas Generator matrix form [a 1 a 2 a 3 a 4] QPSK mapping

Closed Loop Systems • Transmit selection diversity –Antenna(s) chosen which maximizes SINR –Equivalent to receiver selection diversity –Not as good as beamforming –Little bandwidth required –Makes most sense in in deployments with small bandwidths and small delay spreads (low range) • Linear diversity precoding –Feedback channel state information to transmit encoder –Transmit encoder then attempts to fine encoding matrix which maximizes SNR at the receiver –Higher SNR than STBC –Typically use some sort of codebook to reduce feedback bandwidth

Beamforming Systems Narrowband adaptive array or linear combiner interferer • The weight vector is adjusted to improve the reception of some desired signal – Angle of arrival • MUSIC, ESPRIT – Eigenbeamforming • • • No physical interpretation, but useful in multipath environment Minimize some cost function Useful for interference rejection, multipath fading mitigation, and increased antenna gain desired signal

Adaptive Beamforming • Narrowband beamforming is equivalent to spatial filtering –By choosing appropriate sensor coefficients, it is possible to steer the beam in the desired direction –By varying the sensor coefficients (spatial filter taps) adaptively, the interference is reduced • Wideband beamforming requires joint space-time processing –Phase shift at the antennas is frequency dependent –Frequency-dependent response is required (filter) • Common algorithms –Maximum Signal to Interference and Noise Ratio (MSINR) –Minimum Mean Squared Error –Least Mean Squares –Minimum Variance Distortionless Response (MVDR) –Recursive Least Squares –Similar to linear precoding, but may account for interferers

Performance Comparison • MRT refers to maximum ratio transmission – the choice of antenna weights that maximize received SNR • With optimal eigenbeamformer, canceling an interferer is equivalent to dropping an antenna element 3 d. B Modified from: J. Andrews, A. Ghosh, R. Muhamed, Fundamentals of Wi. MAX, Prentice Hall, 2007

Spatial Multiplexing • In rich scattering environments, independent data signals transmitted from different antennas can be uniquely decoded to yield an increase in channel capacity

Spatial Multiplexing Techniques • Open loop (Unknown channel) –Maximum likelihood • Little gain, except at low SNR –Zero-forcing • Closed loop (known channel) –Singular Value Decomposition • Computationally complex • Capacity (assuming waterfilling) • Evaluates pseudo-inverse of H • Can dramatically increase noise power –MMSE • Minimizes distortion • Like Zero-forcing at high SNR, but without the instability at low SNR –BLAST • Layers & codes transmissions across antennas • Effectively linear receiver with successive interference cancellation • Receiver iterates through transmission streams using MMSE or ZF • Works better in lab than real-world due to high SNR requirement • For large SNR, capacity grows linearly with rank of H, approximately min{Nt, Nr} –Approximations guided by • information capacity, • error probability • detection MSE • received SNR –Can tradeoff multiplexing for diversity

Relative Capacity as function of Antenna Array Technique • 19 BS, 3 sectors, spaced 2. 8 km, mix of users • Proportional Fair scheduling Source: Wi. MAX Forum

Correlation/Coupling Effects • Spacing between antennas influence correlation and coupling • Multipath components can act like interference for beamforming which reduces antenna gain 4 x 4, SNR = 20 d. B, 30 AS http: //www. ngwnet. ac. uk/files/wspres/mimo 2. thompson. pdf Beamforming BER [Ref. D. Figueiredo, WPMC’ 04]

Diversity vs. Beamforming • • Diversity Combining Combine signals from different • antenna elements using various algorithms Signal from each element is processed separately Signals have to be uncorrelated • for maximum performance Mitigates fading Increases gain Can improve polarization match • No interference rejection capabilities • Adaptive beamforming Focus the antenna’s gain in the direction of the desired signal – Achieved by manipulating the weights associated with each element Antenna elements have to be separated by /2 to attain a certain phase difference in the signals – Signals are correlated All advantages of diversity combining Has interference rejection capabilities – Typically > 20 d. B

MIMO Summary • Spatial diversity offers incredible improvements in reliability, comparable to increasing the transmit power by a factor of 10– 100. • These diversity gains can be attained with multiple receive antennas, multiple transmit antennas, or a combination of both. • Beamforming techniques are an alternative to directly increase the desired signal energy while suppressing, or nulling, interfering signals. • In contrast to diversity and beamforming, spatial multiplexing allows multiple data streams to be simultaneously transmitted using sophisticated signal processing. • Since multiple-antenna techniques require channel knowledge, the MIMO-OFDM channel can be estimated, and this channel knowledge can be relayed to the transmitter for even larger gains. • It is possible to switch between diversity and multiplexing modes to find a desirable reliability-throughput operating point; multiuser MIMO strategies can be harnessed to transmit to multiple users simultaneously over parallel spatial channels. J. Andrews, A. Ghosh, R. Muhamed, Fundamentals of Wi. MAX, Prentice Hall, 2007

Presentation Overview Theory (32) OFDM and Antenna Array Theory Emerging Standards (24) Cellular and Wi. MAX (16) WLAN (10) WPAN (11) Cognitive Standards ( 7) Interoperability Standards ( 6) Summary and Trends Break & Poster Session 2: 45 -3: 30 http: //www. wisoa. net/members_logos/mobile_in ternet-big. jpg

Cellular and Wi. MAX LTE, UMB, TD-SCDMA, Wi. MAX

Cellular Overview • Two primary competing approaches to 3 G – 3 GPP Family • GSM, GPRS, EDGE, WCDMA, TD-SCDMA (WCDMA-TDD), HSCSD, HSPDA, LTE Advanced • Promotional www. gsmworld. com • Standards www. 3 gpp. org – 3 GPP 2 Family • CDMAOne (IS-95 a, b), 1 x. RTT, 1 x. EVDO, 1 x. EVDV, UMB • Promotional http: //www. cdg. org • Standards www. 3 gpp 2. org – One vision • Voice + high speed data + mobility 3 GPP Declared IP 3 GPP 2 Declared IP – One dominant IP holder (Qualcomm) • New Entrant – Mobile Wi. MAX and Wi. MAX II (802. 16 m) – Standard http: //wirelessman. org/ – Promotional http: //www. wimaxforum. org – Lower cost IP • 350 companies own essential IP • http: //www. eetimes. eu/design/197007324 Source: “ 3 G Cellular Standards and Patents”, David J. Goodman and Robert A. Meyers

GSM Dominates the Landscape http: //www. coveragemaps. com/gsmposter_world. htm • 3 GPP (GSM/WCDMA) has most of the market (77% in 2005, 83% in 2006, 86. 6% in 2008) – Most of that lead is in GSM • 3 GPP 2 (cdma 2000) got a massive jump on 3 GPP – 418/431 million of CDMA is 3 G (www. cdg. org) – 3 GPP 2 = 11. 4%, 3 GPP = 5. 6% • Wi. MAX just cranking up but will be deploying years ahead of LTE

3 GPP Technologies • Generic Access Network (UMA) – • • High Speed Downlink Packet Access • W-CDMA downlink • Packet Switched Handoffs – • Supports handoffs between GSM networks and 802. 11 or Bluetooth networks Enables easier handoffs between different 3 GPP networks Multimedia Broadcast/Multicast Services – Simultaneous broadcast of data streams to multiple recipients • – – 8 -10 Mbps (and 20 Mbps for MIMO systems) over a 5 MHz bandwidth Adaptive Modulation and Coding (AMC), MIMO (Release 6) Hybrid ARQ All IP core network • • (Release 4) Originally ATM • High Speed Uplink Packet Access (Enhanced Up. Link) – Similar technologies to HSDPA on uplink – AT&T in 350 markets • • Table from: http: //www. umtsworld. com/technology/images/hsdpa. png http: //www. mobileburn. com/news. jsp? Id=466 0 Loosely coincides with launch of 3 G i. Phone

3 GPP Long Term Evolution (LTE) E-UTRA Air Interface • Evolved Universal Terrestrial Radio Access • Downlink: Adaptive multilink OFDM (AMLOFDM), which means different bandwidths based on demand Approximate Deployment Schedule – Variable prefix size • 4. 7 ms to 16. 7 ms • Intent to support up to 120 km cells – Called High Speed OFDM Packet Access or HSOPA • • Uplink: SC-FDMA (more later) DL 100 Mbps in 20 MHz (5 bps/Hz) UL 50 Mbps in 20 MHZ (2. 5 bps/Hz) Reduced transition time between states (such as between idle and active states) Variable bandwidth allocations: 1. 25 MHz, 1. 6 MHz, 2. 5 MHz, 10 MHz, 15 MHz and 20 MHz in both the uplink and downlink At least 200 users/cell Load sharing/policy across radio access technologies Support for antenna arrays http: //www. motorola. com/staticfiles/Business/Solutions/Industry Solutions/Service Providers/Wireless Operators/LTE/_Document/6993_Mot. Doc. pdf All IP Core Network – Beamforming, MIMO – Space Division Multiple Access http: //hgmyung. googlepages. com/3 gpp. LTE. pdf

More LTE Details Frame Structure http: //www. motorola. com/staticfiles/Business/Solutions/Industr y Solutions/Service Providers/Wireless Operators/LTE/_Document/6993_Mot. Doc. pdf http: //en. wikipedia. org/wiki/SC-FDMA • SC-FDMA (UL) – Applies frequency domain equalization to single-carrier system – Like spread-OFDM – Transmits serially (single-carrier) – Better PAPR (single carrier) – Less sensitivity to carrier offset – Similar complexity for just equalization – Subframes 0, 5 must be DL – Otherwise arbitrary TDD structure • Other Features – Interference Mitigation – Extensions • But extra steps to effect SC-FDMA – Better battery life – Possibly worse performance in fading channels http: //www. motorola. com/staticfiles/Business/Solutions/Industry Solutions/Service Providers/Wireless Operators/LTE/_Document/6993_Mot. Doc. pdf

TD-SCDMA • Time Division – Synchronous CDMA – Synchronized uplink channels aided by joint detection – China’s 3 G technology • Core network is almost the same as WCDMA – Requires mature 2 G (GSM) network for implementation • Part of the 3 GPP (3 rd Generation Planning Partnership Project) • Multiple chip rates – LCR: 1. 28 Mcps, 1. 6 MHz BW – HCR: 3. 84 Mcps, 5 MHz BW ZTE Corporation, “ 3 GPP Specification Evolution” • TDD link – Does not use paired frequency bands • Optimum for symmetric and asymmetric data services – 1. 6 MHz bandwidth allows flexibly spectrum allocation • Partially motivated by avoiding paying Qualcomm royalties B. Li, D. Xie, S. Cheng, J. Chen, P. Zhang, W. Zhu, B. Li; “Recent advances on TDSCDMA in China, ” IEEE Comm. Mag, vol 43, pp 30 -37, Jan 2005 TD-SCDMA Multiple Access Options

Significant Issues Deploying • Standardized in 1999 • Was going to roll out in 2004 – http: //www. commsdesign. com/news/marke t_news/OEG 20030102 S 0009 • Then 2005 – http: //www. chinadaily. com. cn/english/doc/2 004 -06/23/content_341749. htm • Then 2006 – http: //www. accessmylibrary. com/premium/ 0286/0286 -9623636. html • Then 2007 – http: //www. theage. com. au/news/Technolog y/China-Mobile-to-launch-3 G-mobileservicesend 2007/02/12/1171128898337. html • Now will reportedly issues licenses in 2008 – http: //news. zdnet. com/2110 -1035_226207356. html • Delays make Chinese state-owned service providers unhappy – Grumblings about forgoing TD-SCDMA from China. Mobile (primary deployer) – http: //www. forbes. com/markets/feeds/afx/2 006/01/31/afx 2489964. html • However, China has made it a point of national pride to have the network running for the 2008 Olympics – http: //www. highbeam. com/doc/1 G 1150687033. html – Is already being tested in 10 cities (includes the Olympic cities) but nationwide licenses may not even be issued by the Olympics • http: //www. thestandard. com. hk/news_detail. a sp? pp_cat=1&art_id=54099&sid=15557306&c on_type=1 – First commercial trials supposed to begin April 1, 2008 • http: //www. tdscdmaalliance. org/english/news/list. asp? id=4426 – First public demos in May went badly • http: //www. pcworld. com/businesscenter/articl e/146128/china_shows_off_olympic_techsort _of. html • China won’t allow 3 G or Wi. MAX until TD -SCDMA takes off • Developed a bad reputation – http: //homepage. mac. com/dwbmbeijing/ibl og/Si. Hu/C 520534961/E 20060302210839/i ndex. html – Unnamed China Mobile engineer – “you GIVE me a TD-SCDMA network, and I wouldn't take it. "

Older 3 GPP 2 Technologies • cdma 2000 1 x. RTT – Packet-switched (always on) – Maximum of 144 kbps • Typical 40 -60 kbps – 2 G / 3 G • 1 x EVDO – CDMA EVolution Data Only • Designed to support only data applications – VOIP • Also known as: – CDMA 1 x EV-DO – CDMA EV-DO • EVDO Rev A – Wide deployment • Verizon, Sprint, Kindle best known – Features • • Higher modulation uplink Multi-user packets (time-slots) Lower Latency Couple new data rates downlink (changed code rate) • Promotional – http: //www. evdoinfo. com – Can offer data rates of 384 kbps - 2. 4 Mbps • Does not mix voice traffic with data traffic • Changes modulation, # timeslots Verizon EVDO-Rev A Coverage Map • EVDV (Voice + Data) – Dead on arrival • http: //telephonyonline. com/mag/telecom_evdv _dead/index. html • Qualcomm halted work on the standard in 2005 – http: //news. com/Cell+phone+makers +to+adopt+Internet+calling/2100 -7352_35618191. html – Slow to field http: //www. verizonwireless. com

EVDO Rev B (TIA-856 Rev. B) • Adds Multiple carriers – 2 x. EVDO, 3 x. EVDO, … – Up to 15 1. 25 MHz carriers within 20 MHz • Adds support for 64 -QAM modulation • DL 73. 5 Mbps • UL 27 Mbps • Dynamic non-contiguous carrier allocation • Support for single carrier and multiple carrier subscribers • Standardized 2006 • Trials mid-2007 • Software upgrade (at BTS) to Rev A • Commercial deployments? – No major announcements

EVDO Rev C (UMB) • Spec published Sep 24, 2007 – http: //www. cdg. org/news/press/2007/Sep 24_07. asp – 3 GPP 2 (UMB) beats 3 GPP to market again – Chipsets available nowish • • http: //www. qualcomm. com/press/releases/2007/070327_complete_solution_ultra. html Data rates, mobile with 20 MHz bandwidth – DL: 288 Mbps – UL: 75 Mbps • Key technologies – OFDMA, MIMO, beamforming – Flexible spectrum allocation – Enhanced Qo. S – Support for multiple access technologies – Reduced latency • Likely killed when Verizon went with LTE – http: //www. phoneplusmag. com/hotnews/79 h 20122346. html – Dead on Arrival • http: //www. abiresearch. com/products/research_brief/Wireless_Infrastructure_Research_Briefs/112 – Qualcomm differs (ineffectually) • http: //www. fiercebroadbandwireless. com/story/qualcomm-ceo-umb-not-dead-yet/2008 -01 -14 – Alltel didn’t even say they had considered it (Wi. MAX vs LTE – chose LTE) • http: //www. betanews. com/article/Report_Alltels_choice_of_LTE_a_big_loss_for_Wi. MAX_UMB/121095 6891

802. 16 Family (Wi. MAX) 802. 16 a 802. 16 c 802. 16 d 802. 16 e 802. 16 f Apr 2002 LOS 10 -66 GHz Apr 2003 2 -11 GHz Jan 2003 2 -11 GHz Oct 2004 Combined 802. 16, a, c Dec 2005 Mobile Wi. MAX Dec 2005 Net Management Database (MIB) 802. 16 g Spring 2007 Network management plane 802. 16 h 2009 License-exempt Coexistence 802. 16 i Fall 2008 Mobile Management Information Base 802. 16 j 2009 Mobile Multihop Relay 802. 16 k Aug 2007 Network Management 802. 16 m 2010 4 G Projections based on data at http: //grouper. ieee. org/groups/802/16/published. html Commercialization Roadmap Wi. MAX Forum (2006): Mobile Wi. MAX – Part I: A Technical Overview and Performance Evaluation. Available at www. wimaxforum. org

802. 16 e (Mobile Wi. MAX, 802. 162005) • Ideally, 802. 16 + mobility PHY Spec Overview – Really intended for nomadic or low mobility – Not backwards compatible with 802. 162004 • http: //www. unstrung. com/document. a sp? doc_id=76862 • Direct competitor to 3 G, 4 G, 802. 20 though Wi. MAX Forum once said otherwise • Numerous ongoing deployments and working systems, particularly for Wi. BRO • PHY – Scalable OFDM + Optional MIMO – Convolutional turbo codes – Optional block turbo codes, LDPC Wi. MAX Forum (2006): Mobile Wi. MAX – Part I: A Technical Overview and Performance Evaluation. Available at www. wimaxforum. org

Other Mobile Wi. MAX Features • • • Frame-by-frame resource allocation Hybrid Automatic Repeat Request (HARQ) UL and DL Scheduling Variable Qo. S Three handoff methods – A traditional Hard Handoff (HHO) – Fast Base Station Switching (FBSS) • A list of reachable base stations is maintained by mobile and base stations, but base stations discard packets if not the active BS – Macro Diversity (MDHO) • Same list is maintained, but all base stations in the list can participate in the reception and transmission of packets. • Security – AES for traffic and control data – EAP – Privacy and Key Management Protocol Version 2 (PKMv 2) – 3 -way handshake on handoffs • IP Core Network (supports Voice Over IP) • Multicast Broadcast Services – Like cellular multicast services • Wi. BRO – Defines a set of options for Mobile Wi. MAX for Korean deployment

Wi. MAX Spectrum • Wi. MAX Spectrum Alliances • Regulatory Database – AT 4 Wireless – Launched November 2006 – http: //www. wimaxforum. org/join/spectrum_d emo/ • Wi. MAX Global Roaming Alliance – Brought together unlicensed providers to promote global roaming – Now defunct – Will probably come back in some form – http: //www. theregister. co. uk/2006/09/29/oz_ wimax_roaming_alliance/ • Wi. MAX Spectrum Owners' Alliance – http: //www. wisoa. com/ – Promotes roaming agreements – Participants: – Unwired Australia, Network Plus Mauritius, UK Broadband, Irish Broadband, Austar Australia/Liberty Group, Telecom New Zealand, Wi. MAX Telecom Group, Enertel and Woosh Telecom • 700 MHz band – http: //www. xchangemag. com/articles/501/79 h 13917183935. html? cntwelcome=1 http: //www. wimaxforum. org/news/downloads/supercomm_2005/ WF_Day_in_a_Life_with_Wi. MAX_Final. pdf • Recent reports of interference with C-Band VSAT – http: //www. suirg. org/pdf/SUIRG_Wi. Max. Fie ld. Test. Report. pdf • Officially declared 3 G so 3 G spectrum – http: //www. wirelessweek. com/Wi. MAX-is 3 G. aspx

Mobile Wi. MAX Deployments • First Mobile Wi. MAX products certified April 2008 802. 16 d + 802. 16 e + Wi. BRO – 2. 3 GHz, 4 base, 4 subscriber – POSDATA, Runcom Technologies Ltd, Samsung Electronics Co. , LTD and Sequans Communications – http: //www. wimaxforum. org/news/pr/view? item http: //www. wimaxforum. org/technology/documents/wimax_networks_worldwide_11 x 17. pdf _key=59390 fb 727 bfa 1 • Success appears tied to Sprint 5 b 5 b 8 d 11 bf 9341 b 2 b 11 -Nextel / Clearwire effort 76099 f 8

Clearwire/Sprint Merged Company Clearwire Coverage • Fixed Wi. MAX based wireline replacement service to home + portability within coverage area • 2 Mbps data + voice http: //www. clearwire. com/ Sprint • Mobile Wi. MAX • Rapid deployment to major cities – 10, 000 sites in preparation – 1750 base stations delivered in 2007, 20, 000 antennas • Incorporated into numerous devices (cameras and televisions) • Open Network (support Android) • Federal government connectivity via Wi. MAX – http: //www. wimaxday. net/site/2007/06/05/sprint-planswimax-for-gov%e 2%80%99 t-services/ • http: //www. clearwireconnections. com/pr/pressreleases/050708. p df • Clearwire + Sprint Wi. MAX unit – Called Clearwire • Investors – $3. 2 Billion from Google (500 M), Comcast (1. 05 B), Time-Warner (550 M), Bright House (100 M), Trilogy Equity (10 M) – Sprint owns 51% – Clearwire owns 27% – Investors own 22% • Nationwide focus – 120 -140 million coverage by 2010 • Commercial agreements – Intel will put Wi. MAX in chipsets • Had been planning on that – Google services to be carried (and search provider) – Support Android – Sprint, Comcast, Time. Warner, and Bright House will be wholesale – Sprint contributes its 2. 5 GHz holdings

Wi. Bro • Korean version of 802. 16 e – – • Korean spectrum allocated 2002 – • 2. 3 GHz (100 MHz) Harmonization 802. 16 e/Wi. Bro agreed Nov 2004 – – • Phase 1 standardized by TTA of Korea (2004) Phase 2 standardized in 2005 Samsung joined Wi. MAX Forum Dec 2004 May indicate Samsung’s guess on 4 G direction Plans for Nationwide Korean deployment – – KT & SK Telecom launched June 30, 2006 in Seoul http: //kt. co. kr/kthome/kt_info/pr/news_center/news_view. jsp? pa ge=1&no=397&gubun=1 KT well ahead of SK • http: //www. wimax. com/commentary/blog-2007/wibro-subscriber -numbers-korea-telecom-kt-far-ahead-of-sk-telecom

How does Wi. BRO relate to 802. 16 e? • Wi. MAX Forum: (http: //www. wimaxforum. org/news/press_releases/Wi. Bro_and_Mobile_Wi. MAX_Bac kgrounder. pdf) – “Wi. Bro is the service name for Mobile Wi. MAX in Korea. Wi. Bro uses the Mobile Wi. MAX System Profile. The system profile contains a comprehensive list of features that the equipment is required or allowed to support, and, as a result, Wi. Bro offers the same capabilities and features of Mobile Wi. MAX. ” – It’s Mobile Wi. MAX, just with a different profile (frequency, bandwidth…) • Vendors: Wi. BRO is compatible with 802. 16 e, but there’s more to Mobile Wi. MAX than just 802. 16 e compatibility and many choices in Wi. BRO are different from what is mandatory in 802. 16 e – From (http: //www. nortel. com/solutions/wimax/collateral/wimax_wibro_white_paper. pdf) • Some more important differences from Nortel white paper – Mandatory Handoff • 802. 16 e = HHO • Wi. BRO = FBSS – HARQ • 80. 16 e = Chase combine HARQ • Wi. BRO = Incremental redundancy HARQ – Likely (though unclear) network layer differences

802. 16 j Mobile Multi-hop Relay • Expand coverage, capacity by adding relay stations • Intended for licensed operation • Not intended as a mesh network – Actually a tree • Support mobile units • • Relays controlled from base stations Fixed Relay – Permanent installation – Useful for coverage holes • Nomadic Relay – Temporary fixed installation – Extra capacity for special events (military SDR conferences) • Mobile Relay – Placed on mobile platform to support users on the platform – Useful for public transport (buses, trains) Modified from Fig 1 in IEEE 802. 16 mmr-05/032

IEEE 802. 20 • Fill performance gap between “high data-rate, low mobility 802 standards” and “high mobility cellular networks” • From QTDD/QFDD Proposal • OFDMA data channel • CDMA control channel • Bandwidths – 5 MHz – 20 MHz • MIMO – Single, multiple code word – Pseudo- Eigen beamforming • Space Division Multiple Access – Separate mode from MIMO • Data Rate 260 Mbps – MIMO, 20 MHz • Turbo coding • Time-frequency hopping • Supposed to support inter Radio Access Technology handoffs • Similar to UMB – UMB is effectively an upgrade to MBFDD version – IEEE C 802. 20 -07/14 – Likely same fate (contributions way down) • 802. 20 Shenanigans • Allegations of process abuse brought to a screeching halt when standard suspended in September • Project Launched 2004 • Looked to be dead in the water – Flarion leading proposal – Qualcomm leading vote holder • Turned around when Qualcomm bought Flarion (Aug 05) – http: //www. dailywireless. org/modules. php? na me=News&file=article&sid=4532 • Went to proposal downselection process – Qualcomm (Flarion) TDD, FDD – ETRI – BEST-WINE (Kyocera) • Reapproved in Dec 06 • First meeting Jan 2007

4 G (IMT-Advanced) • • Wireless community already looking towards 4 G Requirements being formalized – – • 1 Gbps fixed 100 Mbps mobile (end-to-end) Support for heterogeneous nets Global roaming Several candidates already emerging – LTE-Advanced – 802. 16 m – NTT Do. Co. Mo’s 5 Gbps prototype 3 G Americas, “Defining 4 G: Understanding the ITU Process for the Next Generation of Wireless Technology, ” July 2007 Available online: http: //3 gamericas. com/PDFs/3 G_Americas_Defining_4 G_WP_July 2007. pdf • http: //www. nttdocomo. com/pr/files/ 20070209_attachment 02. pdf – China’s home grown standard • http: //www. forbes. com/markets/fee ds/afx/2007/09/25/afx 4151478. html • Common techniques – OFDMA, MIMO, small cell sizes optimized for low speed, but support for high speed, IP backbone http: //www. nttdocomo. com/pr/files/20070209_attachment 01. pdf

802. 16 m Requirements • TGm System Requirements Document – http: //wirelessman. org/tgm/docs/8021 6 m-07_002 r 4. pdf – http: //wirelessman. org/tgm/docs/8021 6 m-07_003. pdf • Key functionalities to be added (not defined yet) – Routing – Self Organization – Multi-Carrier – Multi-Radio Coexistence IEEE C 802. 16 m-07/002 r 1 • Minimum Peak Rate – Downlink 6. 5 bps/Hz – Uplink 2. 8 bps/Hz • Latency less than 802. 16 e • Radio Resource Management – Reporting, interference management – Multicast broadcast service – “High-resolution” location determination • Internetworking with: – 802. 11 3 GPP, 3 GPP 2 • Coverage optimized for 5 km, functional to 30 -100 km • Optimized for low mobility (<15 kph), maintain connection up to 350 kph • Optimized for contiguous spectrum but support discontiguous • Reuse/share bandwidth with legacy systems • Direct migration from 802. 16 e

Cellular Summary • Lots of decisions appear motivated by politics and IP costs • UMB, 802. 20 likely dead for different though related reasons • Likely competing standards are LTE and Wi. MAX – Very similar technologies though – General trend of adopting successful technologies • Success of Mobile Wi. MAX highly contingent on success of new Clear. Wire entity – Well funded – If successful, will change cellular business models • Applications finally driving networks (i. Phone, Kindle) • LTE is very slow out of the gate – 3 GPP still has not caught up with 3 GPP 2 – Will LTE be the same? • 4 G a ways out, but preparation is underway

Presentation Overview Theory (32) OFDM and Antenna Array Theory Emerging Standards (24) Cellular and Wi. MAX (16) WLAN (10) WPAN (11) Cognitive Standards ( 7) Interoperability Standards ( 6) Summary and Trends Break & Poster Session 2: 45 -3: 30 http: //www. wisoa. net/members_logos/mobile_in ternet-big. jpg

Wireless LANs 802. 11

802. 11 Alphabet Soup Jun Sep Oct Jun Oct Sep May Jun Sep Dec Mar May 1997 1999 2001 2003 2004 2005 2008 2009 2009 2010 2011 802. 11 a 802. 11 b 802. 11 d 802. 11 f 802. 11 g 802. 11 h 802. 11 i 802. 11 j 802. 11 e 802. 11 k 802. 11 r 802. 11 y 802. 11 n 802. 11 w 802. 11 p 802. 11 z 802. 11 v 802. 11 t 802. 11 u 802. 11 s 802. 11 aa 2 Mbps ISM 54 Mbps UNII 11 Mbps ISM global roaming interoperability 54 Mbps ISM spectrum management security Japanese spectrum real time Qo. S RRM measurements fast roaming US 3. 65 GHz 100 Mbps packet security vehicular (5. 9) Direct Link Setup network management Testing external networks mesh networks Video Transport Streams Past dates are standards approval dates. Future dates from 802. 11 working group timelines Letters are working group (WG) designations. Letters assigned alphabetically as groups created. No WG/ WG document 802. 11 c MAC Bridging work incorporated into 802. 1 d 802. 11 l “typologically unsound” 802. 11 m doc maintenance 802. 11 o “typologically unsound” 802. 11 q too close to 802. 1 q 802. 11 x generic 802. 11 standard 802. 11 t (test) will produce 802. 11. 2 http: //grouper. ieee. org/groups/802/11/Reports/802. 11_Timelines. htm

Wi. Fi Alliance • Industrial consortium that promotes 802. 11 Millions of Wi. Fi Chipset Shipped – www. wi-fi. org • • • Certifies interoperability between vendors’ products Certifies consistency with standards Fills in the gap when 802. 11 standards process is too slow (draft n) Wi. Fi success owes significant debt to Wi. Fi Alliance Line between 802. 11 standards community and Wi. Fi Alliance has gotten very blurry Certifications – 802. 11 a/b/g/n Wi. Fi – 802. 11 e Wireless Multimedia – Draft 2. 0 n Wi-Fi Alliance, Introducing Wi-Fi Protected Setup™, January 3, 2007

Distributed Coordination Function (DCF) • Intended to combat “hidden nodes” in an uncoordinated network and generate fair access to channel • Basic components: –After waiting DIFS after last detected transmission, source sends Request to Send (RTS) –Destination replies with Clear to Send (if OK) –Data is then transferred and ACKed –If an error occurs (e. g. , collision), then station has to wait for DIFS + random backoff. • Random backoff grows with # of collisions • Network allocation vector – Acts as virtual carrier sense – Duration given in RTS/CTS fields • DIFS = DCF Interframe Space • SIFS = Short Interframe Space

802. 11 overhead • Significant overhead involved in 802. 11 – RTS/CTS/ACK SIFS – TCP, IP, MAC framing – Real throughput is rarely come close to PHY raw rate http: //www. cs. tut. fi/kurssit/TLT-6556/Slides/Lecture 4. pdf wireless. ictp. trieste. it/school_2002/lectures/ermanno/System_Performance. ppt

802. 11 n overview • Adds MIMO to WLAN OFDM • Operate in either UNII or ISM bands • Status: –In Ballot –But held up by IP battles Streaming Home Multimedia (HDTV) • http: //arstechnica. com/news. ars/post/2007 0924 -dark-australian-patent-cloud-loomsover-802 -11 n-spec. html • CSIRO (http: //www. csiro. au/) holds some key IP, hadn’t signed letter of assurance, has history of Wi. Fi lawsuits and sought injunctions – Got bought off • Last freely available draft –Enhanced Wireless Consortium (merger of TGn. Sync and WWi. SE) –http: //www. enhancedwirelessconsortiu m. org/home/EWC_PHY_spec_V 127. pd f (PHY) –http: //www. enhancedwirelessconsortiu m. org/home/EWC_MAC_spec_V 124. pd f (MAC) Source: http: //www. tgnsync. org/products

802. 11 n PHY (in 1 slide) • MIMO evolution of 802. 11 OFDM PHY –Up to 4 antennas per device • 20 and 40 MHz channels –Fully interoperable with legacy 802. 11 a/b/g – 288 Mbps in 20 MHz and 600 Mbps in 40 MHz (64 QAM, 4 spatial streams, 1/2 guard interval) –Claim of 100 Mbps in real throughput • Optional enhancements –Transmit beamforming with negligible overhead at the client –Advanced channel coding techniques (RS) –Space Time Block Coding (Alamouti and others) – 1/2 guard interval (i. e. , 400 ns instead of 800 ns) – 7/8 rate coding http: //www. enhancedwirelessconsortium. org/home/EWC_PHY_spec_V 127. pdf

802. 11 n MAC Features • Supports 802. 11 e (Qo. S) • Frame aggregation –Single and multiple destinations • Bi-directional data flow • Link adaptation with explicit feedback and control of channel sounding packets • Protection mechanisms –For seamless interoperability and coexistence with legacy devices • Channel management –Including management of 20/40 MHz operating modes –Channel estimation and feedback • Power management for MIMO receivers • Data aggregation Broadcom, “ 802. 11 n: Next-Generation Wireless LAN Technology, ” White Paper, April 06

802. 11 n Certification • Wi-Fi Alliance Key Certification Features – Certifying to Draft 2. 0 while draft is approved – Certify to Ratified Standard when available – 22 August 2007 - Almost 70 products certified for compliance with Draft 2. 0 of the 802. 11 n • http: //www. wifiplanet. com/news/article. php/3578886 Wi-Fi CERTIFIED™ 802. 11 n draft 2. 0: Longer-Range, Faster-Throughput, Multimedia-Grade Wi-Fi® Networks

802. 11 p Operation • “Dedicated Short Range Communications” (DSRC) – Started in IEEE 1609, spun into 802. 11 p – Aka (WAVE) Wireless Access for Vehicular Environment • IEEE 802. 11 a adjusted for low overhead operations – 54 Mbps, <50 ms latency – 5. 850 to 5. 925 GHz band • Spectrum divided into 7 bands – 178 is control (safety) – 2 edge channels are reserved for future – The rest are service channels (not application specific) • Mix of roadside-to-vehicle and vehicleto-vehicle communications • Questions on business model – http: //www. rita. dot. gov/press_room/pres s_releases/index. html D. Jiang, V. Taliwal, A. Meier, W. Holfelder, R. Herrtwich, “Design of 5. 9 ghz dsrc-based vehicular safety communication, “ IEEE Wireless Comm, Oct 06, pp. 36 -43

802. 11 p Applications • Emergency warning system for vehicles • Cooperative Adaptive Cruise Control • Cooperative Forward Collision Warning • Intersection collision avoidance • Approaching emergency vehicle warning (Blue Waves) • Vehicle safety inspection • Transit or emergency vehicle signal priority • Electronic parking payments • Commercial vehicle clearance and safety inspections • In-vehicle signing • Rollover warning • Probe data collection • Highway-rail intersection warning From: IEEE 802. 11 - 04/ 0121 r 0 Available: http: //www. npstc. org/meetings/Cash%20 WAVE%20 I nformation%20 for%205. 9%20 GHz%20061404. pdf

802. 11 r overview • Fast BSS Roaming/Transition within IEEE WLAN networks – Preserve security with handovers <50 ms • Fast BSS Roaming is possible only within a certain area called the mobility domain (MD), inter-MD cases are not covered – Mobility Domain (MD): Set of BSS grouped together with the same 48 bit MD Identifier – FT functionality seeks to provide handover performance for RT services • Key Issues – Resource Reservations – Security • Collapsed 5 step process down to 3 – Scanning – active or passive for other APs in the area – Authentication with a (one or more) target AP – Re-association to establish connection at target AP • Released 2008 http: //www. cs. tut. fi/kurssit/TLT 6556/Slides/Lect ure 4. pdf

Reduction in Roaming Time S. Bangolae, C. Bell, E. Qi, “Performance study of fast BSS transition using IEEE 802. 11 r, ” International Conference On Communications And Mobile Computing, 2006 http: //www. networkcomputing. com/gallery/2007/0416 t tb. jhtml; jsessionid=0 CK 4 ZKR 20 HC 5 QQSNDLPCKHSCJU NN 2 JVN

802. 11 s • Modify 802. 11 MAC to create dynamic self-configuring network of access points (AP) called and Extended Service Set (ESS) Mesh • Automatic topology learning, dynamic path selection • Single administrator for 802. 11 i (authentication) • Support up to 32 AP • Support higher layer connections • Allow alternate path selection metrics • Extend network merely by introducing access point and configuring SSID 1. http: //standards. ieee. org/board/nes/projects/802 -11 s. pdf IP or Ethernet

802. 11 s • Key Technologies – Topology Formation – Internetworking – Routing – Security • Open 802. 11 s (Linux) – http: //www. open 80211 s. org/ • Numerous Wi. Fi mesh products – http: //www. cs. wustl. edu/~jain/cse 574 -06/ftp/j_jmesh/sld 019. htm Deployment Scenarios http: //ieee 802. org/802_tutorials/nov 06/802. 11 s_Tutorial_r 5. pdf J. Hauser, D. Shyy, M. Green, MCTSSA 802. 11 s Military Usage Case

WLAN Summary • Significant overhead in baseline • 802. 11 n slow to finalize standard – Wi. Fi Alliance certifying to Draft 2. 0 • Most activities directed towards expanding markets – Better support for voice – Vehicular networks – Other spectrum opportunities • 802. 11 j, 802. 11 h (later) – Mesh networks (802. 11 s) – Interoperability with cellular (later)

Presentation Overview Theory (32) OFDM and Antenna Array Theory Emerging Standards (24) Cellular and Wi. MAX (16) WLAN (10) WPAN (11) Cognitive Standards ( 7) Interoperability Standards ( 6) Summary and Trends Break & Poster Session 2: 45 -3: 30 http: //www. wisoa. net/members_logos/mobile_in ternet-big. jpg

Wireless Personal Area Networks

Industry and Open Standards 802. 15. 1 802. 15. 2 802. 15. 3 a 802. 15. 3 b 802. 15. 3 c 802. 15. 4 a 802. 15. 4 b 802. 15. 4 c 802. 15. 4 d 802. 15. 4 e 802. 15. 5 802. 15. 6 IGThz SGRFID SGVLC April 2002 Oct 2003 Jun 2003 May 2008 May 2003 March 2007 Sep 2006 Jan 2009 Mar 2009 Jan 2009? • Proprietary / Industry Bluetooth Coexistence High data rate UWB (high rate) Doc Maintenance mm-wave PHY zigbee (PHY/MAC) UWB (low rate) Updates 802. 15. 4 document Chinese WPAN PHY 950 MHz in Japan MAC for 802. 15. 4 c WPAN Mesh Body Area Networks Terahertz interest group (300 GHz+) RFID Study Group Visible Light 802. 15. 3 a disbanded Jan 2006 MBOA technologies became Wi. Media High speed DS-UWB basically dead after Freescale pulled out – Zigbee (on 802. 15. 4) • Zigbee Pro – – – – Bluetooth (originally) Wi. Bree Wi. Media Z-Wave En-Ocean Insteon Keer Transfer. Jet

Emerging 802. 15 Standards • 802. 15. 4 c (China) – 779 -787 MHz band –Two PHY Modulations: MPSK PHY and OQPSK –Considering OFDM, beamforming • 802. 15. 4 d (Japan) • 802. 15. 5 e –Enhanced MAC for Industrial applications –Modified MAC for 802. 15. 4 c changes • 802. 15. 5 –Mesh networking • Terahertz study group – 300 GHz -> 3 THz –http: //www. ieee 802. org/15/pub/IGthz. html • TG 6 – Body Area Networks –http: //www. ieee 802. org/15/pub/TG 6. html –Just starting • Visible Light Interest Group –http: //www. ieee 802. org/15/pub/IGvlc. html IEEE P 802. 15. 5™/D 0. 01, July 2006

Zig. Bee Standard http: //www. zigbee. org/en/spec_download/download_request. asp – the software – Network, Security & Application layers – Brand management • IEEE 802. 15. 4 – “the hardware” – Physical & Media Access Control layers • PHY – 868 MHz/915 MHz, 2. 4 GHz – Band specific modulations – 20 -250 kbps • MAC – CSMA-CA channel access – Support for ad-hoc networks • Source: http: //www. zigbee. org/en/resources/ • Open source implementations • Open-ZB – http: //www. open-zb. net/ • Meshnetics Open-MAC – http: //www. meshnetics. com/opensource/mac/ Zigbee Pro (Industrial grade) – – – – Network Scalability Fragmentation Frequency Agility Automated Device Address Management Group Addressing Centralized Data Collection Wireless Commissioning

Wi. Media • Industry alliance from MBOA 802. 15. 3 a • Standardized for US in Dec 2005 in ECMA-368 and 369 – http: //www. ecma-international. org/publications/standards/Ecma-368. htm – ECMA used specifically to avoid 802 standardization problems • PHY – – – Multiband OFDM QPSK 53. 3, 80, 106. 7, 160, 200, 320, 400, 480 Mbps nominal data rates Range of 10 m indoor Data can be interleaved across 3 bands, 7 defined patterns (channels) Mandatory support for band group 1 • MAC – – – Peer to Peer, Ad-hoc AES 128 From Fig 28: Support for Dynamic Channel Selection Ranging via propagation delay measurements Bluetooth-like information discovery

Wi. Media Implementations • Primarily marketed as cable replacement • Wireless USB out in Dec 2006 From: http: //www. wimedia. org/en/events/documents/02 Wi. Media_Overview_CES 200 6. ppt –Hub-spoke model –Mandatory support for band group 1 –Mandatory rates of 53. 3, 106. 7, 200 Mbps –Initial Belkin device didn’t live up to the hype • Data rate of 6. 35 Mbits/s • Reportedly not to Wi. Media spec • http: //www. eetimes. com/news/latest/ show. Article. jhtml? article. ID=1966021 48 • Now certified – http: //www. wimedia. org/imwp/idms/pop ups/pop_download. asp? content. ID=119 61 • Bluetooth 3. 0 devices in 2008 – http: //gizmodo. com/gadge ts/wireless/nextgenbluetooth-30 -on-the-way 179684. php • Wireless Firewire and IP also supported over Wi. Media standard

• Status – Nokia sponsored initiative announced Oct 2006 – Specification work is currently being evaluated, targeted for availability second quarter 2007 – Trial chips probably available late 2007 • Public data: (from wibree. com (no more) and http: //www. theregister. co. uk/2006/10/06/wibree_analysis/ ) – – – 2. 4 GHz ISM band Range 10 meters 1 Mbps data rate Targets low power/low cost market From http: //www. computerworld. com. au/index. php/id; 992123146; fp; 4; fpid; 18 • • • Up to 8 devices Master/Slave Turns off frequency hopping Expects different technology to serve as backbone between masters Expects to share resources with full Bluetooth Many reports mentioned Wi. Bree as a competitor to Bluetooth – Brought into Bluetooth fold as low power alternative – “Bluetooth Low Energy” – https: //www. bluetooth. org/About/bluetooth_sig. htm#Bluetooth%20 Wireless%20 Technology – Now a competitor to Zigbee

Z-Wave • Originally Zensys proprietary – http: //www. zen-sys. com/ Z-Wave Alliance • Industry standard “Z-wave” – http: //www. z-wave. com • Low power alternative to Zigbee • PHY – 9. 6 kbps or 40 kbps – GFSK – 100 ft range • 900 MHz ISM • http: //www. z-wavealliance. com/ • http: //en. wikipedia. org/wiki/Z-Wave http: //www. z-wave. com/modules/About. ZWave/? id=21&chk=4 ed 024468 cb 3 d 7 f 9095 aa 54227 ea 1 97 a

Other Proprietary Standards • Transfer. Jet (Sony) • – http: //www. kleer. com – Proprietary low power RF for audio / video –Features • http: //www. sony. net/Sony. Info/News/Pre ss/200801/08 -002 E/index. html • Electric induction field coupling • 3 cm range • 4. 48 GHz center frequency • 560 Mbps (Max) 375 Mbps (effective) • –Demonstrated shortly after announced • http: //www. engadget. com/2008/01/06/vi deo-sonys-transferjet-getsdemonstrated/ En-Ocean – http: //www. enocean. com/en/ – Best known as energy scavengers – Runs a proprietary wireless mesh protocol – Adaptive modulation • “Touch & Get: transfer by touching devices together • Some registration security Kleer • Insteon – Mixes power line comm with RF comm – Industry Alliance (15 manufacturers) • http: //www. insteon. net/allianceabout. html • Wireless Valley is a member – Open source http: //www. efundies. com/

WPAN Summary • Greater reliance on industry standards than other classes of waveforms – Seems to work more smoothly – Bluetooth, Wi. Media, Z-wave • Bifurcation into low power devices (e. g. , Zigbee, Wibree) and high-throughput devices • Impulse UWB as a WPAN appears dead • Heavy emphasis on mesh networks • Possible trend to mix protocols at different mesh levels • Possible later push by Wi. MAX (Clear. Wire / XOhm) into market

Presentation Overview Theory (32) OFDM and Antenna Array Theory Emerging Standards (24) Cellular and Wi. MAX (16) WLAN (10) WPAN (11) Cognitive Standards ( 7) Interoperability Standards Break & Poster Session 2: 45 -3: 30 http: //www. wisoa. net/members_logos/mobile_in ternet-big. jpg

Emerging Cognitive Standards

Cognitive Radio • An approach to wireless engineering wherein the radio, radio network, or wireless system is endowed with the capacities to: – acquire, classify, and organize information (aware) – retain information (aware) – apply logic and analysis to information (reason) – make and implement choices (agency) about operational aspects of the radio, network, or wireless system in a manner consistent with a purposeful goal (intelligent). – “Cognitive Radio Definitions and Nomenclature, ” Working Document SDRF-06 -R-0009 -V 0. 08

802. 22 • Wireless Regional Area Networks (WRAN) – First explicit cognitive radio standard – Aimed at bringing broadband access in rural and remote areas – Takes advantage of better propagation characteristics at VHF and low-UHF – Takes advantage of unused TV channels that exist in these sparsely populated areas – Still defining inter-cell coexistence • Status (IEEE 802. 22 -06/0251 r 0) – Resolving lots of comments – Still developing • 802. 22. 1 – Enhanced interference protection • 802. 2 – Best practices for deployment

Features of 802. 22 • • Data Rates 5 Mbps – 70 Mbps Point-to-multipoint TDD/FDD DFS, TPC Adaptive Modulation – QPSK, 16, 64 -QAM, Spread QPSK • OFDMA on uplink and downlink • Use multiple contiguous TV channels when available • Fractional channels (adapting around microphones) • Space Time Block Codes • Beam Forming – No feedback for TDD (assumes channel reciprocity) • 802. 16 -like ranging • 802. 16 MAC plus the following –Multiple channel support –Coexistence • Incumbents • BS synchronization • Dynamic resource sharing –Clustering support –Signal detection/classification routines • Security based on 802. 16 e security • Collaborative sensing • Techniques in 802. 22 will be extended to other standards and to other bands around the world

Unlicensed White Space Devices • Concept: –Allow unlicensed secondary users into unoccupied TV bands via DSA –“Wi. Fi on Steroids” http: //news. cnet. com/8301 -10784_3 -9901747 -7. html –Only thing really defined is proposed methods for avoidance • Detect and avoid • Geolocate and avoid (perhaps helped by beacon) – Google’s beacon white paper: http: //services. google. com/blog_resources/google_geolocation_white_paper. pdf • Wireless Innovation Alliance (basically the White Space Coalition) –http: //www. wirelessinnovationalliance. com/index. cfm –Key players • Microsoft, Google, Dell, Motorola, Phillips • 1. 5 hr discussion with Larry Page – http: //www. newamerica. net/events/2008/google_unwired • Lots of objections from TV broadcasters and wireless microphone manufacturers / users • Initial problems –Microsoft device broken – DTV recovered signals Microsoft prototype didn’t detect • http: //crtwireless. com/blog/2007/08/02/fcc-report-on-tv-band-prototype-measurementsreleased/ –Motorola device false negatives with strong adjacent channels • http: //www. broadcastingcable. com/article/CA 6560691. html • FCC continuing to review submitted devices –http: //crtwireless. com/blog/2007/11/29/motorola-submits-new-white-space-device-forfcc-testing/

802. 11 h – Unintentionally Cognitive • Dynamic Frequency Selection (DFS) – Avoid radars • – • Listens and discontinues use of a channel if a radar is present Uniform channel utilization Transmit Power Control (TPC) – – Interference reduction Range control Power consumption Savings Bounded by local regulatory conditions

802. 11 y • Ports 802. 11 a to 3. 65 GHz – 3. 7 GHz (US Only) – – • • FCC opened up band in July 2005 Ready 2008 Intended to provide rural broadband access Incumbents – Band previously reserved for fixed satellite service (FSS) and radar installations – including offshore – Must protect 3650 MHz (radar) – Not permitted within 80 km of inband government radar – Specialized requirements near Mexico/Canada and other incumbent users • Leverages other amendments – Adds 5, 10 MHz channelization (802. 11 j) – DFS for signaling for radar avoidance (802. 11 h) • • Working to improve channel announcement signaling Database of existing devices – Access nodes register at http: //wireless. fcc. gov/uls – Must check for existing devices at same site Source: IEEE 802. 11 -06/0 YYYr 0

802. 16 h • Draft 1 to ballot Oct 06, 67% approve, resolving comments) • • Draft 6 to ballot May 2008 Improved Coexistence Mechanisms for License. Exempt Operation Explicitly, a cognitive radio standard Incorporates many of the hot topics in cognitive radio • • – – • Token based negotiation Interference avoidance Network collaboration RRM databases Coexistence with non 802. 16 h systems – Regular quiet times for other systems to transmit From: M. Goldhamer, “Main concepts of IEEE P 802. 16 h / D 1, ” Document Number: IEEE C 802. 16 h-06/121 r 1, November 13 -16, 2006.

IEEE 1900 • IEEE 1900 (aka Standards Coordinating Committee 41 – Dynamic Spectrum Access Networks) – http: //www. scc 41. org/ – 1900. 1 – Terminology and Concepts – 1900. 2 - Recommended Practice for Interference and Coexistence Analysis • Approved • http: //crtwireless. com/blog/2008/04/02/19002 -approved/ – 1900. 3 – Conformance Evaluation for SDR modules – 1900. 4 – Architectural Building Blocks • network resource managers • device resource managers • the information to be exchanged between the building blocks – 1900. 5 – Policy Languages

DARPA’s WNAN Program • Objectives – Reduced cost via intelligent adaptation – Greater node density – Gains in throughput/scalability WNa. N Protocol Stack Optimizing Topology • Leveraged programs – Control Based MANET – low Network overhead protocols – Microsystems Technology Office – RFMEMS, Hermit, ASP MAC – x. G – opportunistic use of spectrum – Mobile Network MIMO - MIMO Physical Wideband Network Waveform – Connectionless Networks – rapid link acquisition – Disruption Tolerant Networks (DTN) – network layer protocols Legend CBMANET WNa. N CBMANET MIMO (MNM) x. G COTS MEMS (MTO) Other programs WNa. N program

Cognitive Radio Summary • Numerous new applications enabled – Opportunistic spectrum utilization, collaborative radio, link reliability, advanced network structures • Commercial implementations starting to appear – 802. 22, 802. 11 h, y, 802. 16 h – And may have been around for a while (cordless phones with DFS) • Significant resistance from incumbents • Standards tend to be highly focused – Work in specific bands • No real standard for white space coalition – Still trying to get blessing to operate in-band • Do. D may emerge into commercial market in the near future • Rolling out incrementally

Presentation Overview Theory (32) OFDM and Antenna Array Theory Emerging Standards (24) Cellular and Wi. MAX (16) WLAN (10) WPAN (11) Cognitive Standards ( 7) Interoperability Standards ( 6) Summary and Trends Break & Poster Session 2: 45 -3: 30 http: //www. wisoa. net/members_logos/mobile_in ternet-big. jpg

Interoperability Standards 802. 21, UMA/GAN 802. 11 u Industry Standards

802. 21 (Media Independent Handoffs) • Key Services – Triggers (state change, predictive, network initiated) – Network Information (services, maps, list of avaialble networks) – Handover commands (client or network initiated, vertical handoffs) • July 2008: Targeted publication http: //www. ieee 802. org/802_tutorials/july 06/802 21 -IEEE-Tutorial. ppt V. Gupta, “IEEE 802. 21 MEDIA INDEPENDENT HANDOVER, ” IEEE 802. 21 session #15 July 17, 2006

• UMA allows to access the mobile voice and data services of the cellular network over a Wireless LAN • Subscribers are enabled to roam and handover between cellular networks and wireless networks • Mobile devices access the Core Network through Unlicensed Mobile Access Network (UMAN). • UMAN has 3 major entities –Unlicensed wireless network –IP access network –UMA Network controller (UNC) http: //www. umatoday. com • UNC authorizes and authenticates the Mobile devices for accessing the Core Network • Part of 3 GPP now –Generic Access Network (GAN) • Products – http: //www. umatoday. com/mobile. Handsets. php http: //www. umatoday. com

• • VCC Addresses shortcomings in UMA’s Voice Call Continuity (VCC) Status – Initiated within 3 GPP in June 2005 – 2006 through requirements, has only fully completed the requirements stage – 2008 being extended to IMS Service Continuity • Different technologies agree to virtual channel – Joint control impossible • Some argue inferior to UMA – http: //www. kineto. com/products/downloads/kineto_wp_UMA_VCC_2007. pdf • Some argue better than UMA – http: //www-hk. huawei. com/publications/view. do? id=1480&cid=2622&pid=127 http: //www. kineto. com/products/downloads/kineto_wp_UMA_VCC_2007. pdf

802. 11 u (Interworking with External Networks) • Standard out in 2010 • Specifically addresses handoffs where user not preauthorized (generally because from another network) • Major Topics – – Network Selection Emergency Call support Authorization from Subscriber Network, Media Independent Handover Support • Supporting information and control messages of 802. 21

Other Cellular + Wi. Fi • Seamless Converged Communication Across Network (SCCAN) – – • Mobile Integrated Go-to-Market Network IP Telephony Experience (Mobile IGNITE) – – • Mobile IGNITE Vendor driven solution http: //www. bridgeportnetworks. com/partners/mobileignite. html Wireless Wireline Convergence Working Group – – • Motorola, Proxim, Avaya – Enterprise solutions http: //www. sccan. org/ Alcatel, Cisco (International Packet Communications Consortium) http: //www. packetcomm. org/index. shtml Bottom line – – Even for standard convergence type activities there’s many different emerging standards. Need for special radios to navigate standards? http: //www. spectralink. com/products/image s/NL-01. gif

Interoperability Summary • • • Proliferation of standards + lack of silver bullet standard means that optimal access technology will vary Supporting growth in use of Vo. IP will make networks less dependent on particular access technologies Biggest issues are: – Getting industries to agree (Herding cats) – Managing security across heterogeneous networks – Harmonizing handoff routines • • 802. 21 is the standard that ties together the vertical handoff standards Heavy focus on Wi. Fi + Cellular Mobile voice traffic Fixed voice traffic Vo. IP traffic Rapid growth ? -92 -93 -94 -95 -96 -97 -98 -99 -00 -01 -02 -03 -04 -05 -06 -07 -08 e e Source: Nokia 13. 6. 2005 Technology used to terminate the call

Presentation Overview Theory (32) OFDM and Antenna Array Theory Emerging Standards (24) Cellular and Wi. MAX (16) WLAN (10) WPAN (11) Cognitive Standards ( 7) Interoperability Standards ( 6) Summary and Trends Break & Poster Session 2: 45 -3: 30 http: //www. wisoa. net/members_logos/mobile_in ternet-big. jpg

Summary and Future Trends

Convergence of Approaches • Wi. MAX becoming more like cellular, cellular becoming more like Wi. MAX • Cellular like waveforms converging to mix of OFDMA + MIMO optimized for low speeds with small cell sizes Source: http: //www. wimaxforum. org/technology/downloads/ Wi. MAX_and_ IMT_2000. pdf • Recognition of this convergence is leading to Wi. MAX being treated like a cellular technology – Sprint’s XOhm network (now Clear. Wire!) – Wi. MAX classified as 3 G • Wi. MAX out of the gate first – Nokia, Motorola, Samsung – http: //www. reuters. com/article/technology-media-telco-SPA/id. USSP 31345620070904 • Because 3 G took so long to deploy, Wi. MAX will steal a march

Breeding Successful Technologies • Mobile Wi. MAX will be a MIMO standard, but so will LTE – Transition of technologies can significantly extend useful lifetime of deployments • Enhanced EDGE • WCDMA + MIMO may steal LTE’s market – 802. 11 n predates mobile Wi. MAX • 802. 22 techniques opening up legacy spectrum for other standards – White Space Coalition – 802. 16 m • Standards can expect to continue to evolve even post-deployment – Need for SDR • May make for smoother transition to 4 G Erik Dahlman, Hannes Ekström, Anders Furuskär, Ylva Jading, Jonas Karlsson, Magnus Lundevall, Stefan Parkvall, “The 3 G Long-Term Evolution – Radio Interface Concepts and Performance Evaluation, ” VTC 06

Take Aways (1/2) • High data rate systems migrating to OFDM + Antenna Array Processing PHY – OFDM – Wi. Media, 802. 11 a, g, 802. 16, 802. 20, 802. 22, UMB, LTE – OFDM + MIMO – 802. 11 n, 802. 16 e, 802. 20, UMB, LTE • More responsive/adaptive resource management (early cognitive radio) – Multiple Qo. S levels – 802. 11 e; 802. 16 e; 802. 20; UMB, LTE, EVDO, – Dynamic channel selection – Wi. Media; 802. 11 h, y; 802. 16 h; 802. 22 – Distributed sensing – 802. 22 • Coexistence given increasing interest – Vertical handoffs – 802. 21, 802. 11 u – Legacy systems – 802. 22, 802. 11 h, y, 802. 16 h • New bands opening up for old techs – 802. 15. 4 d, 802. 11 j, p, y

Take-Always (2/2) • Some spectral harmonization – 5 GHz for Wi. MAX • China pushing own standards – 802. 15. 4 c, TD-SCDMA, TD-SOFDMA • Emergence of Advanced Networking – 802. 11 s, 802. 15. 5, 802. 16 j • Increasing # of technologies – Legacy systems not quickly fading and large # of new ones • Convergence on AES for security – 802. 11 i, Wi. Media, Mobile Wi. MAX • Convergence on all IP Backbone – Mobile Wi. MAX, UMB, LTE

Useful Websites (News, Promotional, Forums, Standards) WLAN www. wi-fi. org www. wi-fiplanet. com/ http: //grouper. ieee. org/groups/802/11/ 802. 15 www. bluetooth. com https: //www. bluetooth. org/ www. wimedia. org http: //www. zigbee. org/en/ http: //www. uwbforum. org/ www. wibree. org http: //www. multibandofdm. org/ http: //grouper. ieee. org/groups/802/15/ 802. 16 www. wimaxforum. org http: //wimaxxed. com http: //wimax. com http: //grouper. ieee. org/groups/802/16/ 3 GPP Family www. gsmworld. com www. umtsworld. com www. gsacom. com www. 3 gpp. org http: //www. tdscdma-forum. org/ 3 GPP 2 Family www. cdg. org www. 3 gpp 2. org 802. 20 http: //grouper. ieee. org/groups/802/20/ 802. 21 http: //www. ieee 802. org/21/ www. umatechnology. org 802. 22 http: //grouper. ieee. org/groups/802/22/ E 2 R “Requirements and scenario definition, ” Available online: http: //e 2 r. motlabs. com/Deliverables/E 2 R_WP 4_D 4. 1_040725. pdf