Virtual matched filtering: a new hybrid CDMA code acquisition technique under Doppler and higher CDMA loads

A new technique for spreading code acquisition is presented. The technique utilizes a multiplicity of communication and processing techniques namely, concatenated short signature coding, convolutional and BCH error/erasure decoding, and pipelining to provide the minimum possible acquisition time in severe overload CDMA and carrier offsets conditions. The overall implementation is equivalent to a very long physical matched filter but is relatively immune to the Doppler degradation such long filter exhibits as will be shown by analysis results. We also propose two strategies in conjunction with the new virtual matched filtering, and compare their performance to known serial, parallel and matched filtering code acquisition techniques