Coded modulation schemes for communication in a noisy channel with noncoherent demodulation

We describe a technique for getting improved coded-modulation performance by using a combination of convolutional codes and a subcode of the nonlinear Nordstrom-Robinson codes on a wireless communications channel. This combination allows for noncoherent demodulation with nonorthogonal signals and obtains large distance between coded waveforms. Since it is nearly as easy to demodulate the Nordstrom-Robinson code as a standard orthogonal modulation the gain is achieved without significant complexity increase.