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 achieve the minimum possible acquisition time in severely overloaded CDMA systems aggravated by carrier offsets. The overall implementation is equivalent to a long matched filter but it is relatively immune to the effects of Doppler induced degradations, as it will be shown in the 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 based code acquisition techniques.