Time Acquisition of IDMA System in Low SNR Environment

Efficient timing synchronization for interleaves must be achieved first before signal detecting and decoding in an IDMA system. However, it is much more difficult to obtain the perfect timing information in IDMA systems than in CDMA systems, owing to the lack of spread gain, especially at the low signal-noise-ratio conditions. In this paper, a conventional sliding-correlate scheme is discussed and a novel scheme based on IDMA system, named Spreading-IDMA, is introduced. The fundamental principle is given and the performance is analyzed. The complexity and average time of the synchronization of the proposed scheme are much less than the conventional one.