Joint User Identification and Channel Estimation in Massive Connectivity with Transmission Control

In this paper, we propose a transmission control scheme and design an approximate message passing (AMP) algorithm for the joint user identification and channel estimation (JUICE) in massive connectivity networks. In the proposed transmission control scheme, a transmission control function is designed to determine a user’s transmission probability, when it has a transmission demand. By employing a step transmission control function for the proposed scheme, we derive the channel distribution experienced by the receiver to characterize the effect of transmission control on the design of AMP algorithm. Based on that, we propose a minimum mean squared error denoiser and design the AMP algorithm. We demonstrate that the proposed scheme can significantly improve the JUICE performance and reduce the average delay, compared to the conventional scheme without transmission control.