Submission Greg Breit, Qualcomm, et al. TGac Channel Model Update May 2009 doc.:IEEE /0575r0 Slide 1 Greg Breit, Hemanth Sampath, Sameer Vermani, Richard Van Nee, Minho Cheong, Byung-Jae Kwak, Myung Don Kim, Jae Joon Park, Naoki Honma, Takatori Yasushi, Yongho Seok, Seyeong Choi, Phillipe Chambelin, John Benko, Laurent Cariou, VK Jones, Allert Van Zelst, Lin Yang, Thomas Kenney, Eldad Perahia, Vinko Erceg, Note: The author list will grow to reflect those providing explicit contributions and review comments

Submission Greg Breit, Qualcomm, et al. Introduction The TGn task group has developed a comprehensive MIMO broadband channel models, with support for 40 MHz channelization and 4 antennas. The TGac task group is targeting > 1 Gbps MAC SAP throughput using one or more of the following technologies: –Higher order MIMO (> 4x4) –Higher Bandwidth (> 40 MHz) –Multi-User MIMO with > 4 AP antennas –OFDMA This contribution summarizes followup work since the March 2009 presentation of the draft TGac channel model addendum document (Breit et al., /0308r1), and represented in the latest Rev 3. May 2009 doc.:IEEE /0575r0 Slide 2

Submission Greg Breit, Qualcomm, et al. General Changes Removal of supporting data and detailed justifications –Revs 1 and 2 of 09/0308 contained large amounts of supporting simulation and measurement data as well as justification text for the various proposed channel model extensions –Rev 3 has been pared down to a direct statement of the model extensions –Supporting data and detailed justification text for 09/0308 are now contained in new contribution 09/0569r0. –Rev 3 now references 09/0569r0 and other supporting documents May 2009 doc.:IEEE /0575r0 Slide 3

Submission Greg Breit, Qualcomm, et al. May 2009 doc.:IEEE /0575r0 Slide 4 MODIFICATIONS FOR LARGE SYSTEM BANDWIDTH

Submission Greg Breit, Qualcomm, et al. Modifications For Large System BW TGn channel model addressed up to 40 MHz system bandwidth, assuming tap-spacing of 10 nsec. For TGac systems with larger overall system bandwidth (W), we propose to decrease channel tap spacing by a factor of Tap spacing reduction is accomplished by linear interpolation of the TGn-defined channel tap powers on a cluster-by-cluster basis May 2009 doc.:IEEE /0575r0 Slide 5 System Bandwidth WChannel Sampling Rate Expansion Factor Channel Tap Spacing W ≤ 40 MHz110 ns 40 MHz < W ≤ 80 MHz25 ns 80 MHz < W ≤ 160 MHz42.5 ns 160 MHz < W ≤ 320 MHz81.25 ns 320 MHz < W ≤ 640 MHz16625 ps 640 MHz < W ≤ 1.28 GHz ps

Submission Greg Breit, Qualcomm, et al. Proposed Method for Tap Interpolation For each cluster in the TGn-defined model, and assuming a channel sampling rate expansion factor k (new sampling rate = k*100MHz), a sequence of k-1 new PDP taps, spaced 10/k ns apart, shall be appended after each TGn- defined PDP tap. The first PDP tap in the sequence shall occur 10/k ns after the TGn-defined PDP tap. The power assigned to each new tap shall be determined by dB-linear interpolation of the TGn-defined PDP tap powers immediately before and after the new PDP tap, in proportion to its position in time relative to the two TGn PDP taps. No new PDP taps shall be added after the final TGn PDP tap for each cluster. May 2009 doc.:IEEE /0575r0 Slide 6 Example for k=4

Submission Greg Breit, Qualcomm, et al. Performance of Tap Interpolation Scheme BCDEF 11n ac May 2009 doc.:IEEE /0575r0 Slide 7 Delay Spread (ns) for Models B-F B (K=1) C (K=1) D (K=2) E (K=4) F (K=4) 11n ac Ricean K factor (linear) calculated from generated channels using the method of Greenstein et al.

Submission Greg Breit, Qualcomm, et al. Performance of Tap Interpolation Scheme Followup simulations performed for 4x4 MIMO –Same parameters as SISO simulations above –Models B and D only –PER curves agree within 0.1dB at 1% and 10% PER May 2009 doc.:IEEE /0575r0 Slide 8 BCDEFF (QPSK ¾) PER=10% PER=1% Link performance comparison: 40 MHz TGn vs. 80 MHz TGac (interpolated) 1x1, 64QAM, 2/3, except last column (Values represent dB difference in required SNR to achieve 1% and 10% PER)

Submission Greg Breit, Qualcomm, et al. May 2009 doc.:IEEE /0575r0 Slide 9 HIGHER ORDER MIMO

Submission Greg Breit, Qualcomm, et al. Higher Order MIMO Retain the TGn Kronecker models for TGac higher order MIMO channel model. Recent measurements and analysis [1] show that –TGn channel models, with appropriately chosen cluster AoA and AoDs tightly bound and sweep the range of MIMO performance observed in real environments. May 2009 doc.:IEEE /0575r0 Slide 10

Submission Greg Breit, Qualcomm, et al. May 2009 doc.:IEEE /0575r0 Slide 11 EXTENSIONS FOR MULTI-USER MIMO

Submission Greg Breit, Qualcomm, et al. MU-MIMO Channel Model Assume TGn-defined cluster AoDs and AoAs as baseline. For each client in the DL: –Apply single random offset of ±180° to the LOS tap AoD and AoA. –Apply single random offset of ±180° to the NLOS cluster AoA –Apply single random offset of ±TBD° to the NLOS cluster AoD. For each client in the UL: –Apply single random offset of ±180° to the LOS tap AoD and AoA. –Apply single random offset of ±180° to the NLOS cluster AoD –Apply single random offset of ±TBD° to the NLOS cluster AoA. Notes: –The ±TBD° value will be updated upon completion of analysis by ETRI [7]. –The random offset can be determined by any well-known algorithm [TBD]. –The appendix will specify the exact algorithm and example values. May 2009 doc.:IEEE /0575r0 Slide 12

Submission Greg Breit, Qualcomm, et al. Advantages of MU-MIMO Model Physically realistic - Introduces statistical AoA/AoD variation across clients Minimal change to TGn channel model Simulation complexity increase is reasonable: –TX/RX correlation matrix need to be computed only once per client, for the entire simulation run May 2009 doc.:IEEE /0575r0 Slide 13

Submission Greg Breit, Qualcomm, et al. DOPPLER-RELATED CHANGES May 2009 doc.:IEEE /0575r0 Slide 14

Submission Greg Breit, Qualcomm, et al. Doppler-Related Changes New measurement results by NTT [8] indicate the following: –The TGn assumptions for main temporal Doppler component (Section 4.7.1) is too high –The fluorescent light effects (mentioned in Section of TGn channel model document) are absent. New text included in channel addendum document: May 2009 doc.:IEEE /0575r0 Slide 15 TGac shall use the Doppler model specified in the TGn channel model document, with the following modifications: In Section of TGn channel model document, the environmental speed, v o, shall be reduced to TBD km/h The effect of fluorescent lighting, as specified in Section of [(TGn channel model doc)], shall not be included

Submission Greg Breit, Qualcomm, et al. May 2009 doc.:IEEE /0575r0 Slide 16 MODEL EXTENSIONS FOR DUAL- POLARIZED ANTENNAS

Submission Greg Breit, Qualcomm, et al. Incorporating Dual Polarized Antennas Dual-polarized antennas are likely to be employed in TGac devices –Reduces real-estate in devices. –Improves MIMO capacity, especially in LOS channel conditions Retain the TGn Dual-Pol channel model for TGac higher order MIMO channel model, with the following parameters: XPD value of 10 dB for the steering matrix H F, XPD value of 3 dB for the variable matrix H v. 0.2 correlation for co-located orthogonally-polarized antenna elements Zero correlation for non-co-located orthogonally-polarized antenna elements Recent measurements and analysis [1] show that –TGn dual-pol channel models, with appropriately chosen cluster AoA and AoDs tightly bound and sweep the range of MIMO performance observed in real environments. May 2009 doc.:IEEE /0575r0 Slide 17

Submission Greg Breit, Qualcomm, et al. Normalization of Channel Matrices Incorporating XPD Modeled channels incorporating XPD should be normalized only to the norm of the co-polarized elements of the channel matrix –Note: Normalization to the Frobenius norm of the entire channel matrix will fail to account for the additional path loss due to transmitting and receiving on orthogonal polarizations May 2009 doc.:IEEE /0575r0 Slide 18

Submission Greg Breit, Qualcomm, et al. References 1.Breit, G. et al. “TGac Channel Model Addendum Supporting Material.” Doc. IEEE /0569r0 2.Erceg, V. et al. “TGn Channel Models.” Doc. IEEE /940r4. 3.Schumacher, L.; Pedersen, K.I.; Mogensen, P.E., "From antenna spacings to theoretical capacities - guidelines for simulating MIMO systems," Personal, Indoor and Mobile Radio Communications, The 13th IEEE International Symposium on, vol.2, no., pp vol.2, Sept Jian-Guo Wang; Mohan, A.S.; Aubrey, T.A., "Angles-of-arrival of multipath signals in indoor environments,"Vehicular Technology Conference, 'Mobile Technology for the Human Race,’ IEEE 46th, vol.1, no., pp vol.1, 28 Apr-1 May Kaltenberger, F.; Kountouris, M.; Cardoso, L.; Knopp, R.; Gesbert, D., "Capacity of linear multi-user MIMO precoding schemes with measured channel data," Signal Processing Advances in Wireless Communications, SPAWC IEEE 9th Workshop on, vol., no., pp , 6-9 July L. J. Greenstein, D. G. Michelson, and V. Erceg, “Moment-method estimation of the Ricean K-factor,” IEEE Commun. Lett., vol. 3, no. 6, pp. 175–176, Jun Kwak, B.-J. et al., “Measured Channel Capacity and AoD Estimation for Multi-User MIMO Scenarios.” Doc IEEE /543r0 8.Yasushi, T. et al., “Measured Doppler Frequency in Indoor Office Environment,” Doc. IEEE /537r0 May 2009 doc.:IEEE /0575r0 Slide 19