| For its particular specialty and advantages, DS-CDMA is widely used in the all fields. It applies to communication syestems and all low power density fields, such as biomedicine, remote measurement and control, tailling and presentiment systems. Meanwhile, It's fit for multi-user systems like navigation, orientation, call and mesurement. However, the synchronization of spreading code is a precondition for good work of all DS-CDMA systems.The synchronization of spreading code includes acquisition and tracking, thereinto, acquisition is more difficult and important. At present, practical implementation can be parallel, serial, or hybrid. And it can be viewed as time region, or frequency region. Also, it can be based on correlator, or match filtering. In substance, all technologies are similar for locally generated PN waveforms having these phases are correlated with the received signal. In this paper, direction for the local phase update is provides with using an auxiliary signal to correlate with the incoming siganl, which speedup the acquisition process.In high dynamic situation, such as LEO satellite spread-spectrum communication systems, wireless navigation and orientation, The notable effects of Doppler shift due to platform danamics must be taken into account. The most approach is to sequentially search all code phases over the range of anticipates frequency offsets. This brute force approach is laborious and can lead to large acquisition times. acquisition times. The approach outlined in this paper utilises an FFT to simultaneously search all possible code Doppler offsets at one time, thus reducing the 2-dimensional search problem to a 1-dimensional code phase search. An increased frequency accuracy is achievable by zeropadding.We completed a hardware roof and realized auxiliary squence generation and FFT. Meanwhiles, we researched some questions with multiple DSPs systems such as JTAG design, boot design, C and assembly mixed programming.
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