Patent ID: 8406352

Claim:
A method for improving symbol estimation in a received data signal, comprising: receiving an input data signal at said receiver, said input data signal comprising at least one modulated carrier encoded with a sequence of information symbols, said modulated carrier modulated using a sequence of discrete time chaotic samples generated at a transmitter, each of said discrete time chaotic samples having a shorter sample time interval than a duration of transmission of each of said plurality of information symbols; generating a replica of said sequence of discrete-time chaotic samples at said receiver; synchronizing said input data signal in time with said replica of said sequence of discrete-time chaotic samples generated at said receiver; correlating said input data signal with said replica to generate a de-spread data signal comprising a plurality of soft symbols; obtaining at least one normalization factor value for each of said soft symbols based on a result obtained from comparing a received symbol energy for each of said plurality of information symbols and a symbol energy of said discrete-time chaotic samples associated with said duration of transmission for each of said plurality of symbols; and using said normalization factor value to reduce an amplitude variance of said de-spread data signal so that a likelihood of incorrect hard symbol decisions due to non-stationary characteristics of a chaotic spreading sequence is reduced.