Noncoherent Massive Space-Time Block Codes for Uplink Network Communications

Abstract

In this paper, we consider multiuser massive multiple-input multiple-output (MIMO) uplink systems in which there are multiple users with each having a single antenna and one base station (BS) with a large number of antennas. It is assumed that each user and BS have neither small-scale nor large-scale channel state information. For such a noncoherent system, we systematically design a series of absolutely additively uniquely decomposable constellation pairs using the phase-shift keying (PSK) constellations such that when any linear combination of two PSK constellation points with positive weight coefficients is received, each individual PSK signal can be uniquely decoded. With this, a novel noncoherent massive space-time block code with PSK modulation is developed for the system. In a noise-free case, we prove that when the number of the antenna at BS grows to infinity, the transmitted symbols and uplink channel can be uniquely determined if the channel coherence time is at least equal to the number of users. In a noisy case, a minimum Euclidean distance detector and a minimum Riemannian distance detector are developed for efficiently and effectively estimating both the channel coefficients and the transmitted signals. Furthermore, a successive two-symbol update receiver is derived for reducing the computational complexity. The benefits of the proposed scheme are illustrated through application examples in multipair two-way massive MIMO half-duplex relaying system and a two-cell massive MIMO uplink system.