Array signal processing optimization in GNU Radio for tracking and receiving applications

Abstract

Among other missions the French German research Institute of Saint-Louis (ISL) works on array signal processing for secured communications between high speed projectiles and allied base stations. Within that framework, a projectile tracking receiving station based on commercial Software-Defined Radios (SDR) was developed using four channels to steer an antenna array and recombine the received signals, hence improving the gain of the receiving station. A transmitter embedded in the projectile sent data to the developed receiving station at a 2 Mbits/s. In order to decode and process in realtime the data received by the four channel antenna array, a high sampling rate was required. As this highly resource consuming application resulted in sample overflows that is, in periodic losses of data between the SDR and the computer, an optimization of our algorithms computed on GNU Radio andthe communication between our blocks proved to be necessary. This paper intends to provide feedback on our optimization work. Some of the main problems we encountered and the solutions we propose to solve them are briefly exposed and will be further detailedin our oral presentation.