Sequentially switched antenna array and application to a WiMAX system

A continuous-switching type array antenna receiver has been proposed in order to reduce the deterioration due to fast-fading channel variations and improve communication performance. The receive antennas are placed in a linear array, and by sequentially switching the elements in the opposite direction to the direction of the train travel, it has been possible to fix the signal receiving point virtually. Through the development of a scale-model experiment of high-speed movement using the prototype antenna, in this paper we show that it is possible through optimized antenna element selection and appropriate signal processing to reduce the fading rate and improve the performance of an OFDM system. A software simulation based on the Worldwide Interoperability for Microwave Access (WiMAX) physical layer parameters was made and data transmitted at RF in a 5 MHz bandwidth with symbol rate appropriately scaled to simulate a range of fading speeds. The receive antenna array consisting of eight elements traverses a track at a virtual speed of 180 km/h and the error rate performances with and without switching are compared.