Patent ID: 6954482

Claim:
A system comprising: at least one transmitter for encoding and transmitting soft-decision trellis-coded differential frequency-hopped spread spectrum (DFHSS) waveforms, wherein the at least one transmitter includes: a B-bit buffer, comprising bits from a data stream, wherein the value of B (a natural number) is the number of bits that will be transmitted per frequency hop; a trellis model, comprising a set of at least two axes, wherein at least one axis corresponds to time and at least one axis corresponds to frequency; a set of M (a natural number) states, corresponding to a set of all possible frequencies that may be transmitted by the system; and branches leaving each state, wherein the branches terminate at allowable transmit frequencies for at least one next frequency hop given a current frequency state; a tone selector, communicatively coupled with the B-bit buffer and trellis model, for selecting a current frequency, given at least one previous frequency and data from the B-bit buffer; a tone generator, communicatively coupled with the tone selector, for transmitting the selected frequency; and a delay element, communicatively coupled with the tone selector and the tone generator, comprising information relating to the current frequency, for feeding back current frequency information to be used as previous frequency information when selecting the at least one next frequency; at least one communication link, communicatively coupled to the at least one transmitter, for transferring soft-decision trellis-coded DFHSS waveforms; and at least one receiver, communicatively coupled to the at least one communication link, for receiving and decoding the soft-decision trellis-coded DFHSS waveforms.