Analysis of modulated signals for direction finding using time modulated arrays

Abstract

A newer technique in the field of direction finding (DF) is the use of time modulated array (TMA) switching harmonics to detect angle of arrival. A switch is used to introduce harmonics to an incoming signal, which are measured and compared to determine angle of arrival (AoA). The work done on this technique has been mostly theoretical and effects such as signal modulation, symbol rate and signal to noise ratio (SNR) of the incoming wave have not been analyzed. When these modulation effects are considered the current method using TMA does not work as effectively. However, if the switching speed is fast enough, compared to the signal characteristics, the effects on the incoming modulated signal are reduced.