Passive coherent location with a prediction of a broadcast signal

An apparatus for passive coherent location comprising:

• a forecaster for generating a prediction, based on a plurality of pre-recorded segments, of a radio-frequency signal transmitted from an antenna of a broadcasting service;
• an evaluator for generating an effectiveness metric from the prediction of the radio-frequency signal;
• a receiver for receiving the radio-frequency signal that an object reflects from the antenna to the receiver;
• and
• a correlator for determining, from the prediction and the radio-frequency signal reflected from the object as received at the receiver, an ambiguity function having a maximum at a temporal offset and a Doppler shift, wherein the temporal offset and the Doppler shift at the maximum partially determine at least a position of the object, wherein the radio-frequency signal is included in a plurality of radio-frequency signals, which each are transmitted from a respective antenna of a respective broadcasting service, the apparatus comprising:
• the forecaster for generating a respective prediction of each of the radio-frequency signals transmitted from the respective antenna of the respective broadcasting service;
• the evaluator for generating a respective effectiveness metric from the respective prediction of each one of the radio-frequency signals;
• a selector for tuning the receiver to a current one of the radio-frequency signals having a higher value of the respective effectiveness metric;
• the receiver for receiving the current one of the radio-frequency signals that the object reflects from the respective antenna to the receiver;
• and
• the correlator for determining, from the current one of the radio-frequency signals reflected from the object as received at the receiver, the ambiguity function having the maximum at the temporal offset and the Doppler shift, wherein the temporal offset and the Doppler shift at the maximum partially determine the position of the object.

An apparatus for passive coherent location, the apparatus comprising:

• a forecaster for generating a prediction of a radio-frequency signal transmitted from an antenna of a broadcasting service;
• an evaluator for generating an effectiveness metric from the prediction of the radio-frequency signal;
• a receiver for receiving the radio-frequency signal that an object reflects from the antenna to the receiver, the receiver further for receiving the radio-frequency signal directly from the antenna;
• a synchronizer for synchronizing the prediction, which assembles a plurality of pre-recorded segments obtained in advance from a playlist for the broadcasting service, with the radio-frequency signal received directly from the antenna;
• and
• a correlator for determining, from the prediction as synchronized by the synchronizer and the radio-frequency signal reflected from the object as received at the receiver, an ambiguity function having a maximum at a temporal offset and a Doppler shift, wherein the temporal offset and the Doppler shift at the maximum partially determine at least a position of the object.