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 d ecoding, and pipelining to achieve the minimum possible acquisition time in severely overloaded CDMA systems aggravated by carrier offsets. The overal l implementation is equivalent to a long matched filter but it is relativel y immune to the effects of Doppler induced degradations, as it will be show n in the results. We also propose two strategies in conjunction with the ne w virtual matched filtering, and compare their performance to known serial, parallel and matched filtering based code acquisition techniques.