Patent ID: 7145937

Claim:
A method for transmitting a modulated signal comprising: obtaining a sequence of data symbols; obtaining a spread spectrum code comprising a sequence of spread spectrum chips; generating a sequence of pre-modulation chips by combining the sequence of data symbols with the spread spectrum chips, wherein for each data symbol, at least one of the pre-modulation chips is generated by taking into account at least the data symbol and at least one of the spread spectrum chips; performing Gaussian Minimum Shift Keying (GMSK) modulation using the sequence of pre-modulation chips to produce a spread spectrum GMSK signal; transmitting the spread spectrum GMSK signal; wherein the spread spectrum GMSK signal adopts antipodal signaling to represent each data symbol; and wherein for each data symbol, if the data symbol takes on a first binary value, a corresponding portion of the spread spectrum GMSK signal exhibits a select waveform, and if the data symbol takes on a second binary value, the corresponding portion of the spread spectrum GMSK signal exhibits a phase-inverted version of the select waveform.