Synthetic aperture radar imaging apparatus and methods
AssigneeUrthecast Corp.
InventorPeter Allen Fox
Life of this patent
Estimating the term…
Abstract
A synthetic aperture radar (SAR) is operable in an interrogation mode and in a self-imaging mode, the self-imaging mode entered in response to determining a response to interrogation pulses have been received from a ground terminal and position information specifying a ground location has been received from the ground terminal. A ground terminal is operable to receive interrogation pulses transmitted by a SAR, transmit responses, and transmit position information to cause the SAR to enter a self-imaging mode. The ground terminal receives first and subsequent pulses from the SAR where subsequent pulses include backscatter and are encoded. The ground terminal generates a range line by range compression.
Claims21
1-29. (canceled)
A method of operation of a synthetic aperture radar (SAR) comprising a transceiver and a hardware data processor, the method comprising:
- causing by the data processor the SAR to enter an interrogation mode, and while in interrogation mode:
- transmitting by the transceiver one or more interrogation pulses;
- determining by the data processor if a response to the one or more interrogation pulses has been received from a terminal;
- and
- determining by the data processor if position information specifying a location has been received from the terminal;
- upon determining by the data processor that a response to the one or more interrogation pulses has been received from the terminal, and position information specifying the location has been received from the terminal, causing by the data processor the SAR to enter a self-imaging mode, and while in the self-imaging mode:
- transmitting by the transceiver a first transmitted imaging pulse;
- receiving by the transceiver a first received pulse that includes the first transmitted imaging pulse that has been backscattered;
- encoding by the data processor the first received pulse to generate a subsequent transmitted imaging pulse;
- and
- transmitting by the transceiver the subsequent transmitted imaging pulse.
A method of generating by a terminal a synthetic aperture radar (SAR) image, the terminal comprising a transceiver, a data store, and a hardware data processor, the method comprising:
- receiving by the transceiver an interrogation pulse transmitted by a SAR;
- transmitting by the transceiver a response to the interrogation pulse;
- transmitting by the transceiver position information specifying a location;
- receiving by the transceiver an nth transmitted imaging pulse transmitted by the SAR;
- storing the nth transmitted imaging pulse in the data store;
- receiving by the transceiver an mth transmitted imaging pulse transmitted by the SAR, wherein m is greater than n, and wherein a radar return received by the SAR includes the nth transmitted imaging pulse that has been backscattered to the SAR, and the mth transmitted imaging pulse transmitted by the SAR includes an encoding of the radar return received by the SAR;
- storing the mth transmitted imaging pulse in the data store;
- decoding by the data processor the mth transmitted imaging pulse to regenerate the radar return received by the SAR;
- and
- generating a range line by the data processor for the SAR image by range compression of the radar return received by the SAR using the nth transmitted imaging pulse as a reference function.
A synthetic aperture radar (SAR) imaging system, comprising:
- a SAR mounted on a SAR platform, the SAR selectively operable in an interrogation mode to transmit a plurality of interrogation pulses;
- and
- a terminal comprising a terminal antenna communicatively coupled to a transceiver, the transceiver communicatively coupled to at least one of a terminal data store and a terminal data processor, wherein the terminal is selectively operable to receive an interrogation pulse and respond by transmitting position information specifying a location to the SAR, and wherein the SAR imaging system, in response to receiving position information from the terminal, generates a SAR image that includes the location specified in the position information received in response to the interrogation pulse.
Dependencies are inferred from the claim text.