Data Acquisition Circuit for Identification of RF Signals’ Direction of Arrival

This paper presents the design, manufacture and tests of a front-end circuit for a Direction Finding (DF) system. The front-end circuit is composed of low noise amplifiers (LNA), multiplexers for selection of the signals received from an antenna array, and a microwave comparator responsible for determining the relative voltage on the antennas’ terminals. A successful testing of the prototype combined with a four-element microstrip antenna array and a software based on the MUSIC (Multiple Signal Classification) validate the proposed front-end circuit.