Number Of Hidden Terminals Research Articles

Hidden Terminal Aware Clustering for Large-scale D2D Networks

In device-to-device (D2D) environments where a number of wireless nodes are connected in ad hoc mode, the most popular mechanism for multiple access control is CSMA/CA as in IEEE 802.11 networks. Consequently, a considerable number of hidden terminals can be found in large-scale and dense D2D networks, and usually they may cause severe performance problems. Previous studies to improve the hidden terminal problem in dense wireless networks have suggested various solutions: e.g., channel assignment, transmit power control, and grouping schemes. In this paper, we adopt a different approach—a hidden terminal aware clustering mechanism, which detects the hidden terminals and enables the nodes to form clusters based on the detected information. A simple polling-based channel access scheme is also proposed such that all nodes belonging to a same cluster can access channel through their neighbors’ polling, which eliminates the hidden terminal problem. Mathematical analysis and simulations show that our proposed scheme significantly improves the performance of large-scale D2D networks.

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

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.

Performance Analysis of S-MAC Protocol with Hidden Terminals

This letter proposes a model that allows the effects of hidden terminals on the performance of the S-MAC protocol to be assessed. The model is used to analyze the impact of the number of hidden terminals on the service delay and throughput of the MAC layer. Simulation results show good agreement with our analytical results, which validates the accuracy of our model.