4 Radiolocation technologies
There are several techniques for using radio signals to determine the position of an object:
- Angle of arrival of a received signal indicates the direction to the transmitter. On its own this does not allow position to be determined as one also needs to know the distance between transmitter and receiver.
- Direct inference of range. Range can be inferred in a number of ways: using signal strength; using techniques for measuring the time-of-flight of the radio signal; using phase of the received signal as a measure of range (assuming techniques for synchronising transmit and receive clocks can be implemented).
- Measuring the time of arrival of a radio signal. In the absence of a definitive time reference (usually the case) ...