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arXiv · 2101.09896

Is Phase Shift Keying Optimal for Channels with Phase-Quantized Output?

Neil Irwin Bernardo·Jingge Zhu·Jamie Evans
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Abstract

This paper establishes the capacity of additive white Gaussian noise (AWGN) channels with phase-quantized output. We show that a rotated $2^b$-phase shift keying scheme is the capacity-achieving input distribution for a complex AWGN channel with $b$-bit phase quantization. The result is then used to establish the expression for the channel capacity as a function of average power constraint $P$ and quantization bits $b$. The outage performance of phase-quantized system is also investigated for the case of Rayleigh fading when the channel state information (CSI) is only known at the receiver. Our findings suggest the existence of a threshold in the rate $R$, above which the outage exponent of the outage probability changes abruptly. In fact, this threshold effect in the outage exponent causes $2^b$-PSK to have suboptimal outage performance at high SNR.

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Neil Irwin Bernardo, Jingge Zhu, Jamie Evans. 2021-01-25. Is Phase Shift Keying Optimal for Channels with Phase-Quantized Output?. https://doi.org/10.1109/isit45174.2021.9518094

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