Patent ID: 7855995

Claim:
A method for implementation of Quadrature Parallel Layered Modulation (QLM) for communications over multiple channels, said method comprising the steps: consider a first set of n p QLM channels starting with a first channel in the set; generating a first communications signal over a frequency bandwidth B at the carrier frequency f 1,0 for a first channel by modulating a first stream of data symbols with a waveform; generating a second communications signal over a frequency bandwidth B at an offset carrier frequency f 1,1 =f 1,0 +B/n p for a second channel by modulating a second stream of data symbols with the same waveform at the same symbol rate and timing as the first stream of data symbols wherein “n p ” is the number of QLM channels overlapping in frequency; for any additional channels in the first set, continuing generation of communication signals over a frequency bandwidth B at an offset carrier frequency by modulating additional streams of data symbols with the same waveform at the same data symbol rate and timing as the first and second streams of data symbols, with frequency offsets increasing in each communication channel in increments of Δf=B/n p until the n p signals are generated for the n p QLM channels in the first set; continuing this generation of n p QLM channels for (ns−1) sets; for (ns−1)>0 generate a second set of n p QLM channels starting with a first channel in the set at bandwidth B with center frequency f 2,0 =f 1,0 +B; repeating the generation of n p communications channels for the second set with each channel offset in frequency in increments of Δf=B/n p relative to the first channel; repeating the generation of n p QLM channels for any additional set; after the last set ns−1 of n p QLM channels one can add another first channel at the center frequency f ns,0 =f 1,0 +(ns−1)×B wherein “x” is a multiply operation; transmitting and receiving said communications signals over a QLM communications link consisting of (ns−1)×n p +1 or (ns−1)×n p QLM channels when another channel is added or not added, recovering data symbols of the communications signals in a receiver using a demodulation algorithm, and combining said algorithm with error correction decoding to recover the transmitted information; whereby frequency offsets have been used as a differentiating parameter to enable QLM parallel channels of communications over a frequency bandwidth ns×B or (ns−1)×B with a data symbol rate which could be above the Nyquist rate, to be demodulated.