1. Proposed TGac Channel Model Revisions (for r6)
Month Year
doc.: IEEE yy/xxxxr0
July 2009
Proposed TGac Channel Model Revisions (for r6)
Date:
Authors:
Greg Breit, Qualcomm Incorporated
John Doe, Some Company

2. Month Year
doc.: IEEE yy/xxxxr0
July 2009
Abstract
Contribution IEEE /0308r5, “TGac Channel Model Addendum” was accepted as the baseline channel model at the May 2009 TGac meeting. This contribution proposes updates to that document reflecting recent experimental studies to resolve “TBDs” in r5 and other editorial activity. Pending approval of these changes by TGac, 09/0308r6 will supercede 09/0308r5 as the current TGac channel model.
Greg Breit, Qualcomm Incorporated
John Doe, Some Company

3. General Editorial Changes
July 2009
General Editorial Changes
Appendix A added
“Generation of Pseudorandom Per-User AoA and AoD Offsets for MU-MIMO Channel Model”
Contents of IEEE /0680r0
New references
Recent experimental studies
References from IEEE /0680r0
Document reformatted into current IEEE template
Greg Breit, Qualcomm Incorporated

4. Changes to Section 4 (Multi-User MIMO )
July 2009
Changes to Section 4 (Multi-User MIMO )
Section title shortened to “Modifications to AoA and AoD for Multi- User MIMO”
Deleted phrase “with up to 16 AP Antennas”
“TBDs” for NLOS DL AoD and UL AoA diversity changed to “±180°”
Based on experimental findings presented in contributions /0543, 0699, and 0822
Simplified text reads:
For each client:
Apply single random offset uniformly distributed over ±180° to the LOS tap AoA
Apply single random offset uniformly distributed over ±180° to the LOS tap AoD
Apply single random offset uniformly distributed over ±180° to the NLOS cluster AoAs
Apply single random offset uniformly distributed over ±180° to the NLOS cluster AoDs
Reference to Appendix A added
Greg Breit, Qualcomm Incorporated

5. Changes to Section 5 (Doppler Model)
July 2009
Changes to Section 5 (Doppler Model)
R5 text:
R6 text:
Recent indoor channel measurements [4] indicate that the magnitude of Doppler assumed in the TGn channel model is too high. 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, vo, may be reduced to TBD km/h.
See [4] for supporting data.
Recent indoor channel measurements [4, 8, 9, 10] indicate that the magnitude of Doppler assumed in the TGn channel model is too high. 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, vo, may be reduced to 0.18 km/h.
Greg Breit, Qualcomm Incorporated

6. Justification for Revision to Doppler Model
July 2009
Justification for Revision to Doppler Model
Doppler parameter refers to ambient environmental channel stirring due to human motion, etc.
AP and client are stationary
Bell-shaped Doppler spectrum centered on 0 Hz
Recent experimental studies in indoor conditions with deliberate pedestrian activity in the channel
DCN 784 (Intel)
ms median coherence time
ms 90%ile coherence time
DCN 828 (NTT)
1.2s coherence time at 90%ile
Propose to assume 400ms channel coherence time
Conservative assumption based on measured data
Corresponds to Doppler spread (fd) of 0.83 Hz [1]
Environmental speed v0 = fdλ = 0.18 km/hr
Greg Breit, Qualcomm Incorporated

7. Changes to Section 6 (Polarization Model)
July 2009
Changes to Section 6 (Polarization Model)
Model revised to assume zero correlation for all orthogonally-polarized elements
True theoretical rho value for cross-polarized antennas
Model in r5 assumes 0.2 correlation for co-located orthogonally-polarized antennas (zero for non-colocated xpol elements)
Forcing a non-zero value (0.2) into the correlation matrix often produces matrices that are not positive definite
Matrices have negative eigenvalues
Cannot be used in the Kronecker channel model implementation
In actuality not physically realistic correlation matrices
Greg Breit, Qualcomm Incorporated

8. Outstanding Item Indoor corridor propagation model
July 2009
Outstanding Item
Indoor corridor propagation model
Current text in document Introduction:
“The scope of this document is limited to extensions of the existing TGn channel model definitions (i.e., Models A-F). The introduction of a new model definition covering indoor corridor propagation is TBD.”
Formal presentation on corridor propagation model is expected from ETRI at September IEEE meeting according to IEEE /0823r0.
Greg Breit, Qualcomm Incorporated

9. July 2009
References
Erceg, V. et al., “TGn Channel Models.” Doc. IEEE /940r4
Breit, G. et al., “TGac Channel Model Addendum.” Doc. IEEE /0308r5
Nishimori, K. et al., “Measured Doppler frequency in indoor office environment.” Doc. IEEE /0537r0
Perahia, E., “Investigation into the n Doppler Model.” Doc. IEEE /0538r0
Kwak, B.-J. et al., “Measured Channel Capacity and AoD Estimation for Multi-User MIMO Scenarios.” Doc. IEEE /0543r1
Breit, G. et al., “Generation of Pseudorandom Per-User AoA and AoD Offsets for MU-MIMO Channel Model.” Doc. IEEE /0680r0.
Breit, G. et al., “Multi-User AoD Diversity Measurements.” Doc. IEEE /0699r5
Perahia, E., “Channel Coherence Time.” Doc. IEEE /0784
Kwak, B.J. et al., “AoD and AoA Estimation for TGac.” Doc. IEEE /0822r0
Kwak, B.J. et al., “Progress Report for Corridor Channel Model for TGac.” Doc. IEEE /0823r0
Yamada, W. et al., “Coherence Time Measurement in NTT Lab.” Doc. IEEE /0828r0
Greg Breit, Qualcomm Incorporated