A radio system (900A, 900B, 1000), comprising: a first radio comprising high-precision, high-stability controllable oscillator comprising a phase-locked loop and voltage controlled oscillator, the first radio acting as a transmitter with two or more antennas (908A, 908B, 908C) configured to broadcast a first signal at a first frequency, and at a subsequent time broadcast a second signal, characterized in that the second signal is broadcasted at a second, different frequency, and the first signal at the first frequency is a high frequency signal; the radio system (900A, 900B, 1000) further comprising a second radio comprising high-precision, high-stability controllable oscillator comprising a phase-locked loop and voltage controlled oscillator, the second radio acting as a receiver having an antenna configured to receive the first and second signals (902A, 902B) broadcasted from the two or more antennas (908A, 908B, 908C) of the transmitter, receiving of the first signal at the first frequency by the receiver triggering the receiver to tune to the first signal to synchronize the transmitter and the receiver; and a processing unit configured to perform the following: measure the amplitude and phase of the first signal at the first frequency as received at the receiver; measure the amplitude and phase of the second signal at the second frequency as received at the receiver; and identify an angle or a direction to the transmitter using the measured amplitude and phase of each signal (902A, 902B). a first radio comprising high-precision, high-stability controllable oscillator comprising a phase-locked loop and voltage controlled oscillator, the first radio acting as a transmitter with two or more antennas (908A, 908B, 908C) configured to broadcast a first signal at a first frequency, and at a subsequent time broadcast a second signal, characterized in that the second signal is broadcasted at a second, different frequency, and the first signal at the first frequency is a high frequency signal; the radio system (900A, 900B, 1000) further comprising a second radio comprising high-precision, high-stability controllable oscillator comprising a phase-locked loop and voltage controlled oscillator, the second radio acting as a receiver having an antenna configured to receive the first and second signals (902A, 902B) broadcasted from the two or more antennas (908A, 908B, 908C) of the transmitter, receiving of the first signal at the first frequency by the receiver triggering the receiver to tune to the first signal to synchronize the transmitter and the receiver; and a processing unit configured to perform the following: measure the amplitude and phase of the first signal at the first frequency as received at the receiver; measure the amplitude and phase of the second signal at the second frequency as received at the receiver; and identify an angle or a direction to the transmitter using the measured amplitude and phase of each signal (902A, 902B). measure the amplitude and phase of the first signal at the first frequency as received at the receiver; measure the amplitude and phase of the second signal at the second frequency as received at the receiver; and identify an angle or a direction to the transmitter using the measured amplitude and phase of each signal (902A, 902B).