The fx489 is a synchronous high - speed modem . its data baud rate and the band - time can be good to satisfy the requirement of ais physics layer . this thesis gives a detailed introduction of the fx489 Fx489是英国cml公司生产的一种单片同步高速modem 。它的数据传输速率和带宽时间分量都能很好的满足ais物理层通信对调制解调指标的要求,因此被本论文选用。