Adaptive symbol timing synchronization method based on maximum likelihood estimation for the realization of multi-mode and multi-service software radio

This paper newly proposes an adaptive symbol timing synchronization method based on maximum likelihood estimation for the realization of multi-mode and multi-service software radio, which is possible to search accurately for the optimum symbol timing from a digitally over-sampled signal without the rate conversion circuit when the system clock rate is non-integer times of the symbol rate for the received system. Thus we can realize multi-mode and multi-service software radio by minimum number of signal processing components like the A/D converter. Finally, we suppose the triple-mode receiver for ITS, which are the Japanese Personal Handy-phone System (PHS), electric toll collection (ETC) and the Global Positioning System (GPS), and evaluate the jitter performance and bit error rate performance by computer simulation.