New CDMA-Based MAC Protocol for Ad Hoc Networks

Abstract

It is widely accepted that Ad Hoc networks are at the leading edge of the research in the domain of wireless networking. These networks are not supported by infrastructure to connect the mobile hosts, thereby they have to be self configured, self organized and the resources have to be allocated in a distributed manner. The medium access control (MAC) layer is seen as the bottleneck for the throughput in wireless Ad hoc networks. Hence, we propose in this work a new Multichannel MAC protocol. The proposed protocol can be based on Code Division Multiple Access (CDMA) or Frequency Division Multiple Access (FDMA). A channel can be represented by one spreading code in CDMA systems or by one frequency band in FDMA case. In our analysis and simulations, we assume that the protocol is based on CDMA technique. We consider one channel for control packets and multiple channels for transmitting data information. We propose that the reservation of a data cannel is done implicitly using the common channel. We show through computer simulations that our proposition of Multichannel MAC protocol improves significantly the communication performance in wireless Ad Hoc networks, even when the introduced overhead is considered.