A novel auto-rate adaptation scheme for wireless ad hoc networks

The IEEE 802.11 wireless media access standard has multi-rate capability in physical layer. These different rates are possible through choosing different modulation schemes. The choice of modulation scheme depends on the current quality of the transmission channel. Present wireless devices often support multiple modulation schemes. However, there are relatively few auto-rate adaptation scheme proposed for wireless Ad Hoc networks to utilize this capability. In this paper we present an auto-rate adaptation scheme called the Sender-Based Auto-Rate (SBAR) scheme. The novelty of SBAR is that SBAR not only possesses efficient channel quality estimation similar to RBAR, but also doesn´t introduce other protocol overhead on the basis of IEEE 802.11. Its rate adaptation is in the sender so that SBAR can be applied to existing equipments without modification to the frame formats in IEEE 802.11. The simulation results of SBAR show that SBAR performs consistently well.