Comparison of convolutional codes against turbo codes for a frequency hopped SDPSK receiver in partial-band jamming

This paper analyzes the performance of a slow frequency hopping waveform, using a new kind of turbo-code named 'frame-oriented turbo-code' with a SDPSK modulation, which could provide medium data rates for a military satcom system. This turbo-code is derived from the classical turbo-code but operates with blocks; the decoder uses a SOVA decoding algorithm. Some results are also provided with a MAP decoder. This concept could be applied to a transparent payload or to an onboard processing system. The paper focuses on the gain of performance with partial-band noise jamming (PBNJ) compared to a classical convolutional encoder (7,1/2) for the same coding rate. Simulation results show a significant gain under PBNJ with different block lengths.