Patent ID: 8457255

Claim:
A method of improving sensitivity in the demodulation of a received signal by a receiver over an arbitrary measurement time epoch, said method comprising the steps of: correlating said received signal with a local replica of pseudo noise code in a coherent fashion creating a correlation signal; and utilizing a Viterbi phase state keying trellis demodulation with a variable resolution of phase states over 0 to 360° to demodulate a radio frequency phase trajectory of said correlation signal throughout the measurement time epoch for improving sensitivity in the demodulation of a received signal, including: breaking the measurement time epoch into time intervals; and creating a trellis of evenly distributed phase state nodes at each time interval, said creating step comprising; defining possible state transitions from each phase state node; creating state transition paths between phase state nodes in one time interval and phase state nodes in another time interval, wherein said creating state transition paths is performed based on a known phase slew rate limitation of said receiver; and assigning a transition probability to each state transition path, wherein the possible state transitions and the probability of the state transition paths are assigned to reflect properties of said receiver.