Performance Analysis of CSMA/CA based Medium Access in Full Duplex Wireless Communications

TL;DR

This paper develops an analytical model for a CSMA/CA-based full duplex MAC protocol in wireless LANs, demonstrating up to 40% throughput improvement and providing insights into hidden terminal mitigation.

Contribution

It introduces the first Markov chain-based analytical model for full duplex MAC protocols and quantifies throughput gains and hidden terminal mitigation effects.

Findings

Up to 40% throughput improvement with full duplex

Analytical expressions for throughput of access point and clients

Full duplex reduces hidden terminal problems

Abstract

Full duplex communication promises a paradigm shift in wireless networks by allowing simultaneous packet transmission and reception within the same channel. While recent prototypes indicate the feasibility of this concept, there is a lack of rigorous theoretical development on how full duplex impacts medium access control (MAC) protocols in practical wireless networks. In this paper, we formulate the first analytical model of a CSMA/CA based full duplex MAC protocol for a wireless LAN network composed of an access point serving mobile clients. There are two major contributions of our work: First, our Markov chain-based approach results in closed form expressions of throughput for both the access point and the clients for this new class of networks. Second, our study provides quantitative insights on how much of the classical hidden terminal problem can be mitigated through full duplex. We specifically demonstrate that the improvement in the network throughput is up to 35-40\% over the half duplex case. Our analytical models are verified through packet level simulations in ns-2. Our results also reveal the benefit of full duplex under varying network configuration parameters, such as number of hidden terminals, client density, and contention window size.