Full-duplex (FD) communication is capable of simultaneously transmitting and receiving data on the same frequency band. To effectively utilize FD in a wireless local area network (WLAN), one must use medium access control (MAC) protocols that consider the characteristics of FD. Many researchers have proposed and analyzed FD MAC protocols for WLANs. Most of this work revealed that as the number of nodes increases, the overall throughput decreases due to collisions. We have found, however, that with a smart MAC protocol, the throughput actually improves as the number of nodes increases. In this paper, we propose an asymmetric FD MAC protocol and then design an FD WLAN analytical model to evaluate saturation throughput. In our analytical model, we consider FD pair probability-the probability that a node capable of FD communication exists. To validate our model, we calculate FD pair probability values based on the modulation and coding scheme (MCS) levels and self-interference cancellation (SIC). We then analyze the effect of the FD pair probability on throughput. Simulation results verify the accuracy of our analytical model. Moreover, we compare the fairness of the proposed and conventional FD MAC protocols. As demonstrated through extensive evaluations, the fairness of the proposed FD MAC protocol is improved.

Full-duplex (FD) radios can transmit and receive packets simultaneously in the same frequency band. Although this potentially doubles the spectral efficiency, it also causes inter-node interference, which was not an issue for half-duplex (HD) radios and can significantly reduce FD radio throughput. This paper proposes a hybrid transmission switching algorithm to reduce performance degradation due to inter-node interference. In contrast to previous studies that only considered channel capacity, we determine the transmission mode by considering the modulation and coding scheme (MCS). The access point compares the required transmission time for HD, FD, and hybrid mode and selects the mode with the best network throughput. We also designed an analytical model to evaluate network throughput for the proposed algorithm. In particular, we consider FD pair probability, which has not been addressed previously. Analytical and simulation results verify that the proposed algorithm improves network performance.

전이중 통신과 비직교 다중접속은 무선랜 시스템에서 처리율 및 스펙트럼 효율성을 증가시키기 위한 기술로 고려되고 있다. 본 논문에서는 MCS 레벨이 가변적인 무선랜 시스템에서 전이중 통신과 비직교 다중접속 기술을 적용한 medium access control (MAC) 프로토콜 제안한다. 제안하는 MAC 프로토콜은 inter-node interference와 전력 할당 계수를 같이 고려한다. 따라서 업링크 노드가 데이터를 AP에게 전송할 때, AP는 다운링크 노드들에게 데이터를 동일한 주파수에서 동시에 전송 가능하다. 시뮬레이션 결과 제안하는 MAC 프로토콜이 기존의 MAC 프로토콜들에 비해 처리율 성능이 증가하는 것을 확인하였다.