Cisco Mesh Access Points - Page 69

Minimum Required
LinkSNR (dB)
Fade Margin =Minimum SNR (dB) +802.11n Date Rate (Mbps)
15969
169712
189918
2291324
2691736
• If we take into account the effect of MRC for calculating Minimum Required Link SNR. Table 16:
Required LinkSNR Calculations for 802.11a/g, on page 53 shows the required LinkSNR for 802.11a/g
(2.4 GHz and 5 GHz) for AP1552 and 1522 with 3 Rx antennas (MRC gain).
LinkSNR = Minimum SNR - MRC + Fade Margin (9 dB)
Table 16: Required LinkSNR Calculations for 802.11a/g
Required Link
SNR (dB)
Fade Margin
(dB)
MRC Gain from
3 RXs (dB)
Minimum SNR
(dB)
Modulation802.11a/g MCS
(Mbps)
9.394.75BPSK 1/26
10.394.76BPSK 3/49
11.394.77QPSK 1/212
13.394.79QPSK 3/418
17.394.71316QAM 1/224
21.394.71716QAM 3/436
24.394.72064QAM 2/348
26.394.72264QAM 3/454
If we consider only 802.11n rates, then Table 17: Requirements for LinkSNR with AP1552 for 2.4 and 5
GHz, on page 54 shows LinkSNR requirements with AP1552 for 2.4 and 5 GHz.
Cisco Mesh Access Points, Design and Deployment Guide, Release 7.3
OL-27593-01 53
Design Considerations
Wireless Backhaul Data Rate