11-11-0422-00-00ac-d0-1-comment-resolution-vht-compressed-beamforming-report-field-and-mu-exclusive-

March 2011doc IEEE 802 11 11 0422r0 Submissionpage 1Youhan Kim Atheros IEEE P802 11 Wireless LANs D0 1 Comment Resolution VHT Compressed Beamforming Report field and MU Exclusive Report field Date March 16 2011 Author s NameAffiliationAddressPhoneemail Youhan KimAtherosyouhan kim Abstract This document provides resolution for CID related the VHT Compressed Beamforming Report field the MU Exclusive Report field in TGac D0 1 CID 36 106 560 884 891 1019 1020 1021 1129 1130 1131 1132 1134 1323 1324 1346 1406 1407 1408 March 2011doc IEEE 802 11 11 0422r0 Submissionpage 2Youhan Kim Atheros CIDSubclausePageLineComment Type CommentSuggestedRemedy 1067 3 1 322238TRThe structure of the VHT compressed beamforming report field for 160M 80 80M is not clearly defined Clarify the spec text and clearly define the structure of the VHT compressed beamforming report field for 160M 80 80M Details of the proposed text change are presented in our contribution 5607 3 1 322238TRNeed better wording to clarify that the two instances of 80 Hz Compressed Beamforming report field are used to convey the compressed beamforming report for 160 and 80 80 MHz Update paragraph starting on line 38 for better clarification 13247 3 1 322241TRFrom For contiguous 160MHz the VHT Compressed Beamforming Report field has the structure defined in Table 7 11 VHT Compressed Beamforming Report field 80 MHz with tone shifting 256 it is not clear if first the upper or lower subband should be included in the feedback report Clarify 13467 3 1 322237 43TRText in this paragraph is unclear Need to describe in detail on the CV FB field for 80 80 and 160 Make new tables similar to 7 11 for 80 80 non contiguous and 160Contiguous modes Specify that there are two sets of SNR reports in 80 80 non contiguous mode March 2011doc IEEE 802 11 11 0422r0 Submissionpage 3Youhan Kim Atheros CIDSubclausePageLineComment Type CommentSuggestedRemedy 11347 3 1 322343TRA note is insufficient here This needs to be normative i e For 160 MHz the subcarrier indicies included are for each segment are given by the 80 MHz row Also it should be stated which segment appears first I assume the low frequency segment Convert note to normative text and also define the segment order 11297 3 1 32165ERIt is unecessary to have separate tables for Nr 5 6 7 Combine into a single table 11307 3 1 32204ERIt is unecessary to have separate tables for 20 MHz 40 MHz and 80 MHz Combine tables into one using parameters similar to Table 7 13 11317 3 1 322022ERThe name of the field and the meaning seem inconsistent Change meaning to Beamforming feedback marix V for subcarrier k 28 Similar throughout 10197 3 1 322038ERBeamforming Feedback Matrix V for carrier 2 is not in case of Grouping 4 Refer Table 7 12 in page 23 Erase the row of Beamforming Feedback Matrix V for carrier 2 13237 3 1 322038TRThe entry Beamforming Feedback Matrix V for carrier 2 isn t true for Ng 4 see Table 7 12 for correct indices Also the entry Beamforming Feedback Matrix V for carrier 2 Ng isn t correct for Ng 4 Remove the entry Beamforming Feedback Matrix V for carrier 2 and change the entries Beamforming Feedback Matrix V for carrier 2 Ng and Beamforming Feedback Matrix V for carrier 2 2Ng to Beamforming Feedback Matrix V for carrier 0 Ng and Beamforming Feedback Matrix V for carrier 0 2Ng resp And change the entry Beamforming Feedback Matrix V for carrier 1 to If Ng 1 Beamforming Feedback Matrix V for carrier 1 otherwise March 2011doc IEEE 802 11 11 0422r0 Submissionpage 4Youhan Kim Atheros CIDSubclausePageLineComment Type CommentSuggestedRemedy we ll get a double count for carrier 1 with above changes for Ng 1 14067 3 1 322038ERBeamforming Feedback Matrix V for carrier 2 is not in case of Grouping 4 Refer Table 7 12 in page 23 Erase the row of Beamforming Feedback Matrix V for carrier 2 10207 3 1 322041 43 ER Beamforming Feedback Matrix V for carrier 2 Ng and Beamforming Feedback Matrix V for carrier 2 2Ng don t match to in case of Crouping 4 in Table 7 12 Page 23 Change Beamforming Feedback Matrix V for carrier 2 Ng and Beamforming Feedback Matrix V for carrier 2 2Ng to Beamforming Feedback Matrix V for carrier Ng and Beamforming Feedback Matrix V for carrier 2Ng respectively 14077 3 1 322041 43 ER Beamforming Feedback Matrix V for carrier 2 Ng and Beamforming Feedback Matrix V for carrier 2 2Ng don t match to in case of Crouping 4 in Table 7 12 Page 23 Change Beamforming Feedback Matrix V for carrier 2 Ng and Beamforming Feedback Matrix V for carrier 2 2Ng to Beamforming Feedback Matrix V for carrier Ng and Beamforming Feedback Matrix V for carrier 2Ng respectively Response AGREE IN PRINCIPLE It would be cleaner to have a single format for all BW modes average SNR per stream followed by per tone V matrix from the lowest subcarrier to the highest subcarrier in frequency This would also eliminate any ambiguity for 160 MHz and 80 80 MHz CIDSubclausePageLineComment Type CommentSuggestedRemedy 367 3 1 322241TR 256 should be replaced with 128 As in comment March 2011doc IEEE 802 11 11 0422r0 Submissionpage 5Youhan Kim Atheros CIDSubclausePageLineComment Type CommentSuggestedRemedy 10217 3 1 322241TRwith tone shifring 256 is written However in case of 160MHz the tone index is 250 250 Change with tone shifring 256 to with tone shifring 250 14087 3 1 322241TRthe line says with tone shifring 256 However in case of 160MHz the tone index is 250 250 Change with tone shifring 256 to with tone shifring 250 Response AGREE IN PRINCIPLE The rewritten 7 3 1 32 now explicitly defines subcarrier indices thus tone shifting is no longer required CIDSubclausePageLineComment Type CommentSuggestedRemedy 8847 3 1 322248TRDid not understand the term 22 in the text The SNR values in Table 7 9 VHT Compressed Beamforming Report field 20 MHz Table 7 10 VHT Compressed Beamforming Report field 40 MHz and Table 7 11 VHT Compressed Beamforming Report field 80 MHz are encoded as an 8 bit twos complement value of 4 SNR average 22 where SNR average is the sum of the values of SNR per tone in decibels divided by the number of tones represented This encoding covers the SNR range from 10 dB to 53 75 dB in 0 25 dB steps Should it have been 10 Assuming 8 bits represents from 0 to 63 75 in quarter dB precision and the factor 10 shifts it to 10 to 53 75 Response March 2011doc IEEE 802 11 11 0422r0 Submissionpage 6Youhan Kim Atheros DISAGREE 10 dB 22 32 Then 32 4 128 which is the lower limit of an 8 bit twos complement integer Similarly 53 75 dB 22 31 75 Then 31 75 4 127 which is the upper limit of an 8 bit twos complement integer Thus the current text is correct However to avoid similar confusions in the future suggest converting the equation to a table explicitly mapping the value of the field to the SNR value CIDSubclausePageLineComment Type CommentSuggestedRemedy 11327 3 1 322256TRIt is not clear from the description what exactly grouping is It is described as a method for reporting a single value for a group Ng of adjacent subcarriers But what exactly is this single value The table seems to imply that it is for a specific subcarrier the subcarrier identified in the table Sufficient to say for group Ng of contiguous subcarriers remove adjacent they can t all be adjacent The text needs to be specific as to whether this is a single subcarrier that represents the group or whether it is some average value Response DISAGREE How to come up with the single value for a group is implementation specific CIDSubclausePageLineComment Type CommentSuggestedRemedy 8917 3 1 332423TRThe definition of N should be more tightly related to the average SNR per stream Change line to is the average noise plus interference power measured at the beamformee that was used to calculate SNR bar Response AGREE IN PRINCIPLE However definition of N has now been moved to subclause 7 3 1 32 which makes this comment no longer relevant March 2011doc IEEE 802 11 11 0422r0 Submissionpage 7Youhan Kim Atheros Proposed Resolution Text TGac editor Edit subclauses 7 3 1 32 and 7 3 1 33 as follows 7 3 1 32 VHT Compressed Beamforming Report field The VHT Compressed Beamforming Report field is used by the VHT Compressed Beamforming frame see Error Reference source not found to carry explicit feedback information in the form of angles representing compressed beamforming feedback matrices V for use by a transmit beamformer to determine steering matrices Q as described in 9 19 3 Explicit feedback beamforming and 20 3 12 2 Explicit feedback beamforming The size of the VHT Compressed Beamforming Report field depends on the values in the VHT MIMO Control field The VHT Compressed Beamforming Report field contains the channel matrix elements indexed first by matrix angles in the order shown in Table 7 1 to Table 7 5Table 7 X1 Order of angles in the Compressed Beamforming Report field Compressed Beamforming Feedback Matrix subfield and second by data subcarrier index from lowest frequency to highest frequency The explanation on how these angles are generated from the beamforming feedback matrix V is given in 20 3 12 2 5 Compressed beamforming feedback matrix In Tables 7 X1 Order of angles in the Compressed Beamforming Feedback Matrix subfield Ncis the number of columns in a compressed beamforming feedback matrix determined by the Nc Index field of the VHT MIMO Control field Nris the number of rows in a compressed beamforming feedback matrix determined by the Nr Index field of the VHT MIMO Control field Table Error No text of specified style in document 17 X1 Order of angles in the MIMO Compressed Steering Matrices Report field compressed beamforming feedback matrix subfieldfor Nr 4 Size of V Nr Nc Number of angles Na The order of angles in the Quantized Beamforming Feedback Matrices Information field 5 18 11 21 31 41 21 31 41 51 5 214 11 21 31 41 21 31 41 51 22 32 42 32 42 52 5 318 11 21 31 41 21 31 41 51 22 32 42 32 42 52 33 43 43 53 5 420 11 21 31 41 21 31 41 51 22 32 42 32 42 52 33 43 43 53 44 54 5 520 11 21 31 41 21 31 41 51 22 32 42 32 42 52 33 43 43 53 44 54 Table Error No text of specified style in document 3 Order of angles in the MIMO Compressed Steering Matrices Report field compressed beamforming matrix V for NrNr 6 Size of V Nr Nc Number of angles Na The order of angles in the Quantized Beamforming Feedback Matrices Information field 6 110 11 21 31 41 51 21 31 41 51 61 6 218 11 21 31 41 51 21 31 41 51 61 22 32 42 52 32 42 52 62 6 324 11 21 31 41 51 21 31 41 51 61 22 32 42 52 32 42 52 62 33 43 53 43 53 63 6 428 11 21 31 41 51 21 31 41 51 61 22 32 42 52 32 42 52 62 33 43 53 43 53 63 44 54 54 64 6 530 11 21 31 41 51 21 31 41 51 61 22 32 42 52 32 42 52 62 33 43 53 43 53 63 44 54 54 64 55 65 6 630 11 21 31 41 51 21 31 41 51 61 22 32 42 52 32 42 52 62 33 43 53 43 53 63 44 54 54 64 March 2011doc IEEE 802 11 11 0422r0 Submissionpage 10Youhan Kim Atheros 55 65 Table Error No text of specified style in document 4 Order of angles in the MIMO Compressed Steering Matrices Report field compressed beamforming matrix V for NrNr 7 Size of V Nr Nc Number of angles Na The order of angles in the Quantized Beamforming Feedback Matrices Information field 7 112 11 21 31 41 51 61 21 31 41 51 61 71 7 222 11 21 31 41 51 61 21 31 41 51 61 71 22 32 42 52 62 32 42 52 62 72 7 330 11 21 31 41 51 61 21 31 41 51 61 71 22 32 42 52 62 32 42 52 62 72 33 43 53 63 43 53 63 73 7 436 11 21 31 41 51 61 21 31 41 51 61 71 22 32 42 52 62 32 42 52 62 72 33 43 53 63 43 53 63 73 44 54 64 54 64 74 7 540 11 21 31 41 51 61 21 31 41 51 61 71 22 32 42 52 62 32 42 52 62 72 33 43 53 63 43 53 63 73 44 54 64 54 64 74 55 65 65 75 7 642 11 21 31 41 51 61 21 31 41 51 61 71 22 32 42 52 62 32 42 52 62 72 33 43 53 63 43 53 63 73 44 54 64 54 64 74 55 65 65 75 66 76 7 742 11 21 31 41 51 61 21 31 41 51 61 71 22 32 42 52 62 32 42 52 62 72 33 43 53 63 43 53 63 73 44 54 64 54 64 74 55 65 65 75 66 76 Table Error No text of specified style in document 5 Order of angles in the MIMO Compressed Steering Matrices Report field compressed beamforming matrix V for NrNr 8 Size of V Nr Nc Number of angles Na The order of angles in the Quantized Beamforming Feedback Matrices Information field 8 114 11 21 31 41 51 61 71 21 31 41 51 61 71 81 8 226 11 21 31 41 51 61 71 21 31 41 51 61 71 81 22 32 42 52 62 72 32 42 52 62 72 82 8 336 11 21 31 41 51 61 71 21 31 41 51 61 71 81 22 32 42 52 62 72 32 42 52 62 72 82 33 43 53 63 73 43 53 63 73 83 8 444 11 21 31 41 51 61 71 21 31 41 51 61 71 81 22 32 42 52 62 72 32 42 52 62 72 82 33 43 53 63 73 43 53 63 73 83 44 54 64 74 54 64 74 84 8 550 11 21 31 41 51 61 71 21 31 41 51 61 71 81 22 32 42 52 62 72 32 42 52 62 72 82 33 43 53 63 73 43 53 63 73 83 44 54 64 74 54 64 74 84 55 65 75 65 75 85 8 654 11 21 31 41 51 61 71 21 31 41 51 61 71 81 22 32 42 52 62 72 32 42 52 62 72 82 33 43 53 63 73 43 53 63 73 83 44 54 64 74 54 64 March 2011doc IEEE 802 11 11 0422r0 Submissionpage 11Youhan Kim Atheros 74 84 55 65 75 65 75 85 66 76 76 86 8 756 11 21 31 41 51 61 71 21 31 41 51 61 71 81 22 32 42 52 62 72 32 42 52 62 72 82 33 43 53 63 73 43 53 63 73 83 44 54 64 74 54 64 74 84 55 65 75 65 75 85 66 76 76 86 77 87 8 856 11 21 31 41 51 61 71 21 31 41 51 61 71 81 22 32 42 52 62 72 32 42 52 62 72 82 33 43 53 63 73 43 53 63 73 83 44 54 64 74 54 64 74 84 55 65 75 65 75 85 66 76 76 86 77 87 The angles are quantized as defined in Table 7 6Table 7 X2 Quantization of angles All angles are transmitted LSB to MSB Table Error No text of specified style in document 67 X2 Quantization of angles Quantized Quantized radians k 2 b 1 2 b 2 where 0 1 2 1 b is the number of bits used to quantize defined by the Codebook Information field of the VHT MIMO Control field see Error Reference source not found radians k 2 b 1 2 b where 0 1 2 1 b is the number of bits used to quantize defined by the Codebook Information field of the VHT MIMO Control field see Error Reference source not found The VHT Compressed Beamforming Report field for 20 MHz has the structure defined in Table 7 7 VHT Compressed Beamforming Report field 20 MHz where Na is the number of angles used for beamforming feedback matrix V see Table Error No text of specified style in document 1 to Table Error No text of specified style in document 5 Table Error No text of specified style in document 7 VHT Compressed Beamforming Report field 20 MHz Field Size bits Meaning SNR in space time stream 18Average signal to noise ratio in the STA sending the report for space time stream 1 SNR in space time stream Nc8Average signal to noise ratio in the STA sending the report for space time stream Nc Beamforming Feedback Matrix V for carrier 28Na b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 28 NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 28 2NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 1Na b b 2Beamforming feedback matrix V March 2011doc IEEE 802 11 11 0422r0 Submissionpage 12Youhan Kim Atheros Beamforming Feedback Matrix V for carrier 1Na b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2Na b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2 NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2 2NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 28Na b b 2Beamforming feedback matrix V The VHT Compressed Beamforming Report field for 40 MHz has the structure defined in Table 7 8 VHT Compressed Beamforming Report field 40 MHz where Na is the number of angles used for the beamforming feedback matrix V see Table Error No text of specified style in document 1 to Table Error No text of specified style in document 5 Table Error No text of specified style in document 8 VHT Compressed Beamforming Report field 40 MHz Field Size bits Meaning SNR in space time stream 18Average signal to noise ratio in the STA sending the report for space time stream 1 SNR in space time stream Nc8Average signal to noise ratio in the STA sending the report for space time stream Nc Beamforming Feedback Matrix V for carrier 58Na b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 58 NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 58 2NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2Na b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2Na b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2 NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2 2NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 58Na b b 2Beamforming feedback matrix V The VHT Compressed Beamforming Report field for 80 MHz has the structure defined in Table 7 9 VHT Compressed Beamforming Report field 80 MHz where Na is the number of angles used for the beamforming feedback matrix V see Table Error No text of specified style in document 1 to Table Error No text of specified style in document 5 Table Error No text of specified style in document 9 VHT Compressed Beamforming Report field 80 MHz Field Size bits Meaning March 2011doc IEEE 802 11 11 0422r0 Submissionpage 13Youhan Kim Atheros SNR in space time stream 18Average signal to noise ratio in the STA sending the report for space time stream 1 SNR in space time stream Nc8Average signal to noise ratio in the STA sending the report for space time stream Nc Beamforming Feedback Matrix V for carrier 122Na b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 122 NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 122 2NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2Na b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2Na b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2 NgNa b b 2Beamforming feedback matrix V Beamforming Feedback Matrix V for carrier 2 2NgNa b b 2Beam