PHASE MAPPING FOR QPSK/QBL-MSK WAVEFORM

摘要

A method of pulse shaping a spread signal of serially formatted in-phase (I) and quadrature (Q) waveforms, where each waveform includes a predetermined number of chips per symbol, includes (a) examining adjacent chips of the I and Q waveforms at a symbol boundary; and (b) determining that one of the I or Q waveforms, includes two adjacent first and second chips separated by a single chip period, where the first chip belongs to a previous symbol and the second chip belongs to a present symbol. If the chips are of the same value, the method extends a peak value between the first and second chips, and zeros the other waveform of the I or Q waveform during the extended duration. If the chips are of opposite values, then the method zeroes one of the chips and inserts a chip into the other waveform.