doc.: IEEE /1290r0 Submission November 2010 Allert van Zelst, QualcommSlide 1 VHT-SIG-B in NDPs Date: Authors:

doc.: IEEE /1290r0 Submission November 2010 Allert van Zelst, QualcommSlide 2 Authors (contd):

doc.: IEEE /1290r0 Submission November 2010 Allert van Zelst, QualcommSlide 3 Abstract This presentation proposes fixed bit patterns for VHT- SIG-B to fill in a TBD in the 11ac spec framework ( r15).

doc.: IEEE /1290r0 Submission November 2010 Allert van Zelst, QualcommSlide 4 Introduction The 11ac specification framework ( r15) defines: –The VHT NDP format is shown in Figure 8 and has the following properties: has the same format as the VHT PPDU but with no data portion has a VHT-SIG-A indicating a SU packet and has VHT-SIG-B carrying a TBD fixed bit pattern Figure 8 -- VHT NDP format This presentation proposes bit patterns for VHT-SIG-B

doc.: IEEE /1290r0 Submission November 2010 Allert van Zelst, QualcommSlide 5 Disadvantage of Using the Normal SU Content of VHT-SIG-B for NDPs For NDPs, the VHT-SIG-B length field will be zero, resulting in very high Peak-to-Average Power Ratios (PAPRs) The PAPR of VHT-SIG-B with a length field of 0, with a four times oversampled IFFT, equals –for 20 MHz: dB –for 40 MHz: dB –for 80 MHz: dB

doc.: IEEE /1290r0 Submission November 2010 Allert van Zelst, QualcommSlide 6 Proposal for Fixed Bit Patterns in VHT-SIG-B of NDPs Select bit patterns in the 20, 21, and 23 useful VHT- SIG-B bits for 20, 40, and 80 MHz, respectively, that have the lowest Peak-to-Average Power Ratio (PAPR) –The following sequences (showed LSB first) result in the lowest PAPR when using a four times oversampled IFFT 20 MHz: (PAPR = 3.16 dB) 40 MHz: (PAPR = 5.42 dB) 80 MHz: (PAPR = 5.13 dB)

doc.: IEEE /1290r0 Submission November 2010 Allert van Zelst, QualcommSlide 7 Pre-motion Move to accept the bit patterns as listed on slide 5 as the fixed bit patterns for VHT-SIG-B in VHT NDPs? –Y –N –A