I was wondering how cell coverage density rates are calculated.
Setting cell_density to 'normal' on my QCA9560 802.11bgn interface results in these rates in the hostapd configuration:
supported_rates=55 60 90 110 120 180 240 360 480 540
The wifi phy supports:
HT TX/RX MCS rate indexes supported: 0-23
RX HT20 SGI
RX HT40 SGI
According to MCS tables the highest rate for MCS index 23 HT, 40 MHz short GI is 450 Mbps and 216.7 Mbps for 20 Mhz short GI.
The configured basic_rates match no valid MCS index data rate, and out of the supported_rates 55 and 110 don't match, 60, 90, 120, 180, 240, 360 only match 40 MHz short GI and 480, 540 are out of range.
Is this fine? Does hostapd ignore invalid rates? What happens if 40 MHz is not available since there's not a single valid 20 MHz rate left?