Open Source Software Defined Radio Research Articles

GnuRadar: An Open-Source Software-Defined Radio Receiver Platform for Radar Applications

In this article, we present the development and integration of an existing cost-effective, open-source software-defined radio (SDR) receiver into a complete, pulsed-radar system used to study meteor reflections that ablate in the Earth's atmosphere. The use of SDR technology in radar applications is not, in itself, a new concept, but details regarding construction of back-end processing, formatting, and storage have not been widely discussed. More specifically, SDR systems, in general, are used to provide a communication link, meaning that precise time of arrival and signal levels are not of primary importance, but these parameters are critical in a radar system. This article addresses in detail methods used to redesign an existing, open-source receiver into a pulse-synchronized radar system for use by anyone interested in cost-effective radar data acquisition solutions. Additionally, we provide test data from an experimental observation to validate operation and performance of the resulting system.

Measured Multi-User MIMO Capacity in Aircraft

The multipath richness typical of aircraft channels represents a potentially well-suited environment for multi-user multiple-input multiple-output technology (MU-MIMO). This paper presents results from measurements of the achievable MU-MIMO data rates in a Rockwell T-39 Sabreliner, using an open-source software-defined radio (SDR) test bed. We also compared the achievable capacity of dirty-paper coding (OPC) against time-division multiple access (TDMA) to illustrate the value of advanced MU-MIMO techniques in aircraft environments. Measured data was then compared against values obtained from a three-dimensional ray-tracing simulation. For transmitters located near the ends of the aircraft, the average error between simulated and measured capacity was on the order of 2% or less. For the more-centralized transmitter location, simulations predicted an average of 6% less capacity than what was actually measured.