136 Energy-Efficient Rate Adaptation
to differentiate losses between wireless channel fading and frame collisions.
Other statistical based algorithms, such as SampleRate [14] and RRAA [15],
also require explicit feedback of transmission result of each frame.
PHY-metric based algorithms. RBAR [16] adopts RTS/CTS to
obtain SNR (Signal-to-Noise Ratio) and selects data rates by looking up a
predetermined SNR-data rates table. However, RTS/CTS is not supported in
LDmesh networks with TDMA-type MAC. SoftRate [17] uses confidence in-
formation from the physical layer to estimate the prevailing channel BER (Bit
Error Rate). The PHY layer coding used has to be implemented on software
radios, which limits its prevalence on off-the-shelf 802.11 commodity hard-
ware. ...