🤖 AI Summary
This study addresses the limited throughput gains of full-duplex (FD) WLANs in hidden terminal scenarios, where performance remains constrained by the CSMA/CA-based Distributed Coordination Function (DCF). The paper presents the first systematic modeling and theoretical analysis of saturated throughput for both FD and half-duplex (HD) WLANs under DCF in such environments. By developing an accurate analytical model, the work quantifies the throughput improvement achievable with FD operation and reveals that, under typical parameter settings, FD yields only a modest 10%–20% throughput gain over HD. These findings provide critical theoretical insights into the practical efficacy of FD in existing MAC-layer protocols and offer valuable guidance for future protocol design.
📝 Abstract
Full Duplex (FD) technology is considered as one of the next big leap in the evolution of modern WLANs. Allowing a node to simultaneously transmit a data frame while in receive mode, can theoretically double the system throughput. However, several requirements must be fulfilled in order for FD operation to manifest. One obvious prerequisite is that the Medium Access Control (MAC) mechanism must allow two nodes to access the shared medium simultaneously. In modern WLANs the standard MAC layer mechanism is the Distributed Coordination Function (DCF), which is specifically designed to avoid such situations. FD communications may also take place when the physical placement of the communicating parts involves the existence of hidden terminals which, in standard Half Duplex (HD) communications, imposes a significant problem. This paper investigates the performance of the Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) protocol, which constitutes the basis of the DCF mechanism, in FD WLANs with hidden terminals, and compares it with the standard HD case. Our analysis is based on performance modelling. Results indicate that, under the DCF regime, FD technology exhibits an exiguous performance improvement, in terms of saturation throughput, when compared with its half duplex counterpart.