Abstract: To utilize the spatial diversity effectively for combating the fading caused by the multipath propagation, a distributed antenna system based on a software-defned radio platform is designed and implemented. Compared with traditional schemes, the system converges the data received by each front-end to another computer, which can equalize the computation load among different computers and is suitable for the software-defned radio architecture. Specifcally, software-defned radio platforms consisting of four computers and universal software radio peripherals (USRP) are used as inner receivers at different positions. In this paper, through a switch, the four inner receivers are connected to an extra computer which is used as an outer receiver for signal decoding and other operations. Besides, superframe number is delivered in the idle bits of transport parameter signaling to achieve the synchronization between inner receivers and outer receiver. The scheme achieves distribution processing of inner receivers and the outer receiver with the capability of realizing the space diversity and the computing balance, accordingly, performing good practicability and expansibility. The test results in the practical wireless scenario show that the distributed antenna system can achieve the spatial diversity and improve the overall performance compared with a single receiver.

Key words: software-defned radio, distributed antenna system, spatial diversity