OFDMA Based Multiparty Medium Access Control in Wireless Ad Hoc Networks

Abstract

We present the Concurrent Transmission or Reception Multiple Access (CTRMA) protocol as an example of embracing interference in wireless ad hoc networks, even when each node is endowed with a single half-duplex radio and a single antenna. CTRMA uses OFDMA to enable each node to either send or receive multiple concurrent transmissions over orthogonal subchannels (groupings of subcarriers). With CTRMA, a node transmits multiple transmissions at the same time by negotiating the subchannels over which transmissions take place by using information attained with a channel priority assignment algorithm. CTRMA supports dynamic bandwidth selection and enhances channel reuse. We prove the correctness of CTRMA and use simulation experiments to illustrate the major performance advantages of CTRMA over prior channel access protocols proposed for single-radio single-channel, single-radio multi-channel and multi-radio multi-channel wireless ad hoc networks.

Evaluating dynamic OFDMA subchannel allocation for wireless mesh networks on SDRs

“…They propose a protocol called Concurrent Transmission or Reception Multiple Access [13], which assigns multiple subchannels to each link in the network depending on traffic demands and the number of interfering links. Furthermore, they introduce a MAC protocol called CoCo-MAC [14,15], which allocates groups of subcarriers within pre-assigned subchannels for concurrent communication with multiple neighbors.…”

“…The authors of [13,14,15] employ simulations to evaluate OFDMA-based PHY and MAC mechanisms for wireless mesh networks. They propose a protocol called Concurrent Transmission or Reception Multiple Access [13], which assigns multiple subchannels to each link in the network depending on traffic demands and the number of interfering links.…”

OFDMA for wireless multihop networks: From theory to practice

“…On the one hand, existing work analyzes subchannel allocation algorithms [6,7] to find the optimal resource allocation in a WMN. On the other hand, some authors deal with the link layer in OFDMA WMNs [8,9]. Centralized solutions to both issues exist [10,11] but are typically not well-suited for WMNs, since WMNs often operate in a distributed manner.…”

Practical OFDMA for corridor-based routing in Wireless Multihop Networks

“…On the one hand, existing work analyzes subchannel allocation algorithms [7], [14] to find the optimal resource allocation in a WMN. On the other hand, some authors deal with building complete systems to exploit OFDMA in WMNs [18], [19]. Still, they do not take routing into account.…”