Collaborative Beamforming for Communication Applications Using a Two-Element Fully-Wireless Open-Loop Coherent Distributed Array

TL;DR

This paper demonstrates a wireless two-node coherent distributed communication system using SDRs, achieving high data rates and reliable transmission without external synchronization in an urban environment.

Contribution

It introduces a fully-wireless open-loop coherent distributed array system with on-node processing, enabling high-rate communication without external references.

Findings

Achieved a mean coherent gain of 0.936 across experiments.

Transmitted up to 64-QAM with a symbol error ratio below 1.4e-4.

Supported reliable bandwidth of up to 12 Mbps.

Abstract

In this work we demonstrate a proof of concept of a fully-wireless two-node open-loop coherent distributed communication system and evaluate its performance by transmitting QPSK , 64-, and 256-QAM constellations at a symbol rate of 2 MBd over a 58 m link in an urban environment. The system is implemented in a distributed manner with on-node processing using software-defined radios (SDRs) and wireless internode communication to share coordination information and does not rely on external time or frequency references such as the global navigation satellite system (GNSS). In each experiment ~100 messages were transmitted and a mean coherent gain of 0.936 was achieved across all measurements with a mean symbol error ratio of below $1.4\times 10^{-4}$ achieved up to 64-QAM, demonstrating a reliable bandwidth of up to 12 Mbps.