Research On Distributed Space-Time Coding In Ad Hoc Networks

With the rapid growth in demand for high quality wireless communication, wireless communication technology also needs to be upgraded. In the future communication systems, the introduction of Multiple-input Multiple-output (MIMO) technology is an effective way to increase communication capacity. However, in the wireless network systems (such as Ad hoc networks), dut to the limited power, size and cost, the terminals can not be equipped with multiple diversity antennas. In recent years, the rising Distributed Space-Time Coding (DSTC) technology has provided an effective way to solve this problem. DSTC builds a distributed MIMO transmission system to improve transmission quality and capacity of network using the spatial distributed multiple single-antenna terminals.In order to further extend the effective communication range of Ad hoc networks and improve the system transmission quality and capacity, a novel DSTC scheme on Ad hoc networks is proposed. In the scheme, an accurate wireless transmission range model on Packet Error Rate (PER) and 2×2 DSTC transmission model are built. The validity of proposed scheme is verified by the simulations. Theoretical analysis and simulation results show that the scheme can increase the capacity of the system and the ability of combating fading. Moreover, the range of wileless communication system is enlarged. Besides, a double channel Medium Access Control (MAC) layer protocol process based on 2×2 DSTC model is presented to resolve exposed and hidden nodes problems.