An Efficient Timing Synchronization Technique for Fft Based Multi-carrier Direct Sequence Spread Spectrum Transceiver *

An eficient timing synchronization technique for a low complexdp FFT based multi-carrier direct sequence spread spectrum IF/baseband transceiver is presented. The timing synchronization control loop consists of a robust acquisition loop and a tracking loop that eliminates the timing phase ofiset caused by the transmission delay, sampiing error, and channel noise. The acquisition loop reduces the probability y of false lock by continuous threshold checking and adjusting process. Both the acquisition and the tracking loop incorporate a simple feedback mechanism for a practical VLSI transceiver implementation. The tz~ect of the sampling oflset on the performance of the timing acquisition is discussed. The highest operating speed of the receiver is the Nyquist sampling rate, but the entire synchronization is performed using the low speed baseband signals. The performance of the synchronization under the additive white Gaussian noise channel is assumed.