Non-Coherent Rate Splitting for the MISO BC with Magnitude CSIT

TL;DR

This paper introduces a rate splitting scheme for a MISO broadcast channel where the transmitter knows only the channel magnitudes, not phases, improving achievable rates through superposition coding.

Contribution

It proposes a novel non-coherent rate splitting method for MISO BC with magnitude-only CSIT, expanding the capacity region compared to existing schemes.

Findings

Achievable rate region is enlarged using the proposed scheme.

Superposition coding effectively exploits magnitude-only CSIT.

The method outperforms traditional schemes with phase information limitations.

Abstract

A rate splitting based scheme is proposed to operate a broadcast setting with two antennas at the transmit side and two single-antenna receiving terminals. The transmitter knows the magnitude of the channel coefficients, and it is oblivious to the phase information. Each transmit antenna, with a power constraint, sends a private message and a common message to be decoded by both receivers. An achievable rate region is obtained, which enlarges the capacity region of the vector broadcast channel with vector channel magnitude feedback by means of superposition coding.