Performance Evaluation of the Networks with Wi-Fi based TDMA Coexisting with CSMA/CA

The wireless technology is widely used in industries with timing stringent tasks. However, it lacks of the consideration of the co-channel interference when designing and estimating the performance of the media access strategies. Thus, it is hard to guarantee the real-time and reliable packet transmissions. In this study, we first propose a Wi-Fi based TDMA access scheme to provide the stringent timing and reliability guarantees under the coexistence with the CSMA/CA scheme. Then, we theoretically analyze the delay of the Wi-Fi TDMA scheme and the throughput of the CSMA/CA scheme considering mutual interferences. The effectiveness of the proposed Wi-Fi TDMA scheme is demonstrated by numerous simulation results since the results show that the retransmission times and the average access delay of the TDMA station are small when varying the CSMA/CA packet length, TDMA packet length, TDMA slot length and TDMA duty cycle. The simulation results also show that the analysis TDMA delays are almost the same with the simulation ones which indicate the accuracy of our theoretical analysis models. Additionally, numerous simulations have been done to show the impact of the Wi-Fi TDMA scheme on the typical CSMA/CA scheme by varying the TDMA frame length and the TDMA duty cycle under centralized and distributed slot assignment strategies.