System and method for determining the relative direction of an RF transmitter

A method to determine a relative direction of a target light transmitter, performed by a direction finding (DF) system comprising a central unit having a processing module and at least a pair of light sensors having a light-wave-absorbing material between them, the method comprising;

• sending light signals in which the target light transmitter transmits light signals received at each one of the light sensors of the DF system;
• measuring the signal strength of the target light transmitter received at each light sensor;
• calculating the difference between the signal strength measured at each one of the light sensors in the pair;
• determining a relative direction of the target light transmitter to be the direction of the light sensor within the pair of light sensors in which the stronger light signal was measured.