Per-Antenna Power Minimization in Symbol-Level Precoding

Abstract

Abstract-This paper investigates the problem of the interference among multiple simultaneous transmissions in the downlink channel of a multi-antenna wireless system. A symbol-level precoding scheme is considered, where the data information is used, along with the channel state information, in order to exploit the multi-user interference and transform it into useful power at the receiver side. In this framework, it is important to consider the power limitations individually for each transmitting antenna, since a common practice in multi-antenna systems is the use of separate per-antenna amplifiers. Thus, herein the problem of per-antenna power minimization in symbol-level precoding is formulated and solved, under Quality-of-Service constraints. In the proposed approach, the precoding design is optimized in order to control the instantaneous power transmitted by the antennas, and more specifically to limit the power peaks, while guaranteeing some specific target signal-to-noise ratios at the receivers. Numerical results are presented to show the effectiveness of the proposed scheme, which outperforms the existing state of the art techniques in terms of reduction of the power peaks and of the peak-to-average power ratio across the transmitting antennas.

Symbol-level precoding with per-antenna power constraints for the multi-beam satellite downlink

“…For instance, denoting by P Sat the saturation power of the amplifiers, a possible choice for the PACs could be P The problem (4) can be solved, in the same fashion of [22], based on a bisection procedure on the solution of the equivalent power minimization problem. The related per-antenna power minimization problem is addressed and solved by the authors in [32]. Hereinafter, for the sake of completeness, the problem formulation and the solution derivation are recalled.…”

Symbol-Level Multiuser MISO Precoding for Multi-Level Adaptive Modulation

“…It has been shown in various literature that symbol-level precoding shows considerable gains in comparison to the conventional group-or user-level precoding schemes [18]- [30]. The main reason is that in symbol-level precoding the vector of the aggregate multiuser interference can be manipulated, so that it contributes in a constructive manner from the perspective of each individual user.…”

Spatial peak power minimization for relaxed phase M-PSK MIMO directional modulation transmitter

“…1. This results in a less stringent design compared to [14]- [16] and consequently reduces the power consumption at the transmitter.…”

“…As a solution, we can design a directional modulation transmitter with spatial peak power minimization. To this end, the references [14], [15] consider constant envelope precoding for a single-user massive MIMO system and the authors in [16] consider a perantenna power minimization based on constructive interference where there is a strict constraint on the phase of the received symbols. In addition to the hardware considerations, the mobile communications consume a large amount of energy which is responsible for a considerable amount of environmental pollution [17].…”

“…A constant envelop design such as [14], [15] results in non-convex problems and conservative designs. Also, the constructive interference approach in [16] considers a fixed phase design for low peak power to average ratio, which results in a stringent design. However, there is no work on addressing a joint design considering both amplifier distortion and energy efficiency.…”