The Research On Spreading Spectrum Code Fast Synchronization Using SAW Convolvers

Accurate and fast synchronization technology plays an important role in the efficient utilization of any spread-spectrum system. Comparing with other search methods, a technique for the rapid acquisition of a direct spread-spectrum signal using Surface Acoustic Wave Device (SAWD) has many advantages. Because of element limitations and application difficulties, we haven't seen some spread-spectrum systems employing SAWD as the core element. Through theoretics analyses and experiments of fast synchronization technology using SAW convolver, this paper outlines that SAW convolver performs as passive matched-filter, realizing rapid acquisition. On the other hand , fast synchronization and decording are completed by checking the moment and detecting the change of auto-correlative peak pulses of PN code. The paper also illustrates the basic properties and limitation of SAW convolver. As a result, a few significant conclusions are drawn. These principles form the basis of making use of the whole section of SAW convolver effective area, upon which this system scheme is proposed. A rapid acquisition technique is presented, based upon the use of parallel processing of a long spreading sequence simultaneously in SAW convolvers. Some important conclusions of analyses are demonstrated by hardware circuit experiments and simulation software.