ANALYZING THE CAPACITY OF GENERALIZED-K FADING CHANNELS AT LOW SNR

Abstract

In this work, we have characterize the low SNR capacity of Nakagami-gamma also known as generalized-K fading channel in nats per channel use with perfect channel state in-formation at both transmitter and receiver(CSIT-R). We have focus in Low SNR regime because wireless systems are now operating at Low SNR to have a higher energy e - ciency. We have shown that Low SNR capacity of generalized-K fading channel scales as

4m SNR log2

1 SNR

, where m is the distribution shaping parameter and is de ned in terms of channel mean square as = E[x2] k , where k is also the shaping parameter. Our Asymptotic Low SNR capacity follows the exact results obtained from simulation which justify our analysis. We also provide an on-o scheme that is achieving our Low SNR capacity results which indicates that this scheme can be practically implemented at Low SNR. Further, we also Analyze another important parameter called energy e - ciency of generalized-K fading channel at Low SNR in nats per channel use per joules and also characterize the Minimum energy per nat that is required for reliable commu- nication.