Covert Communications with Channel Inversion Power Control in the Finite Blocklength Regime

In this letter, we investigate covert communications with finite blocklength under the channel inversion power control (CIPC) scheme, where a transmitter is allowed to communicate with a receiver without transmitting the pilot signals, which facilitates the hidden of the transmitter from the warden. Considering both the conventional and truncated CIPC schemes, we provide the novel expressions of the optimal detection threshold and the minimum total error probability at the warden. Furthermore, the optimization of the power control parameter at the transmitter is presented to maximize the effective covert throughput, which quantifies the amount of the information bits transmitted from the transmitter to the receiver subject to the covert constraint, under two kinds of CIPC schemes.