Capacity of Peak and Average Power Constrained Additive Generalized Gaussian Noise Channels

In this letter, we derive new closed-form, lower and upper bounds on the capacity of the additive white generalized Gaussian noise (AWGGN) channel with both peak and average power constraints. Analytically, we prove that the difference between the upper and lower bounds is bounded above by 1.45 nats. Numerically, for practical values of the system parameters, we show that this difference is almost negligible. We study the asymptotic properties of these bounds as the peak amplitude increases. We also prove that the proposed bounds are concave in the average transmit power. These results can be quite useful for optimization and system design over AWGGN channels.