Backward compatible receiver structure for C8PSK HART

This paper presents a low-complexity C8PSK HART receiver structure that can adaptively demodulate input signal modulated in non-coherent HART FSK or coherent HART C8PSK. Spectrum leakage and barrier effect, which are defects of windowed DFT when used to analyze signal spectrum, are employed to perfectly solve both problems of channel estimation and signal identification. In order to lower power consumption of the receiver, a novel algorithm is developed for HART FSK demodulation, reusing the resource of HART C8PSK demodulator. Simulations have shown that the proposed structure can work very well in low SNR.