Multiple Antenna Combining for Sequentially Switched Antenna Array Receivers

Abstract

Mobile traffic from many smartphone devices to base stations is rapidly increasing. In a case many users communicate in moving vehicles such as a bullet train, it is desirable to multiplex their traffic and relay it to a base station located along the railroad line for improving spectral efficiency. However, high speed channel variation occurs on the entrance circuit of a bullet train. A sequentially switched antenna array receiver is known as a promising technology for compensating such channel variations. This technology slows down the channel variation by switching the antenna element in the opposite direction of the train travel in order to practically fix the receiving point. When designing such a receiver, spatial intervals between the antenna elements and temporal switching intervals need to be considered. In this paper, we propose a multiple antenna combining scheme to satisfy the requirements for the sequentially switching, and show its effectiveness via computer simulations.