dB - attenuation/amplification of the power level - expressed as the base 10 logarithm of the ratio of the power of two signals, as shown here:
- dB = 10 x Log10 (P1/P2)
dBm - uses same calculations as dB, but has a reference value of 1mW. Can also describe receiver sensitivity in -dBm.
Data networks: AP separation of 120-130 feet
Voice networks: cell edge at -67dBm, 2 non overlapping APs at an RSSI +35
baseline power of 35-50mw
requires 15% more APs than a 100mW deployment
APs have an aggregate throughput less than the data rate because the 802.11 provides a reliable transport mechanism that ACKs all packets, thereby halving the throughput on the channel.