High resolution direction finding algorithms-applications in the HF band

The application of high resolution spectral estimation techniques like MUSIC in radio direction finding (DF) is becoming more and more important. Simulation results can give a good measure of the performance of an algorithm, but it is not possible to include all practical influences. This is especially true for DF in the HF band (3-30 MHz), where special effects due to the propagation via the ionosphere can occur. This includes fading of the received signals, multipath propagation via different ionospheric paths, time dependent variations of the great circle bearing and others. These effects may decrease the performance of high resolution DF algorithms. We present some measurement results for various high resolution algorithms. The results were obtained by using a nine channel DF system.