# US 2023/0054822 A1 · Uav ground penetrating radar array > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2023/0054822 A1 - Document ID: US20230054822A1 - Status: Published application - Kind: A1 - Application number: 16/779,339 - Filed: 2020-01-31 - Published: 2023-02-23 - Earliest claimed: 2020-01-31 - Assignees: Lawrence Livermore National Security, LLC - Applicants: Lawrence Livermore National Security, LLC - Inventors: N. Reginald Beer; Steven Bond; Peter C. Haugen; Jacob Trueblood; Brian Matthew Wihl - Web page: https://patentgrep.com/patent/US20230054822A1 ## CPC - G01S 7/4082: {using externally generated reference signals, e.g. via remote reflector or transponder} - G01S 13/885: {for ground probing (prospecting or detecting using electromagnetic waves G01V3/12)} - G01S 7/40: Means for monitoring or calibrating - G01S 13/003: {Bistatic radar systems; Multistatic radar systems} - G01S 13/0209: {Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband} - G01S 13/87: Combinations of radar systems, e.g. primary radar and secondary radar - G01S 13/89: for mapping or imaging - G01V 3/12: operating with electromagnetic waves {(operating with millimetre waves G01V8/005)} - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) ## Abstract A GPR system the implements a modified multistatic mode of operation is provided. The GPR is suitable for mounting on an unmanned aerial vehicle. The GPR system has radar transceivers. The GPR system transmits transmit signal serially via the transceivers. For each transceiver that transmits a transmit signal, the GPR system receives a return signal acquired by each transceiver except for a return signal for the transceiver that transmits the transmit signal. The GPR system outputs of matrix of return signals that includes a null value for the return signals of the transceivers that transmit. ## Claims ### Claim 1 A method performed by an electronics system associated with a first signal system having a radar antenna, the method comprising: transmitting a calibration transmit signal via the radar antenna; receiving a calibration receive signal that is different from the calibration transmit signal based at least in part on degradation of the calibration transmit signal as it travels from the first signal system to a destination; identifying a transfer function that maps the calibration transmit signal to the calibration receive signal; identifying a pre-compensated transmit signal that when input to the transfer function outputs a desired receive signal; and transmitting the pre-compensated transmit signal so that a resulting pre-compensated receive signal will approximate the desired receive signal based on a degradation of the pre-compensated transmit signal as it travels from the first signal system to a destination. ### Claim 2 (depends on 1) The method of claim 1 wherein the calibration receive signal is a reflection of the calibration transmit signal. ### Claim 3 (depends on 2) The method of claim 2 wherein the calibration receive signal represents multiple reflections of the calibration transmit signal from multiple reflection surfaces. ### Claim 4 (depends on 2) The method of claim 2 wherein the calibration receive signal is further different from the calibration transmit signal based on degradation of the calibration transmit signal resulting from the reflection. ### Claim 5 (depends on 1) The method of claim 1 wherein the calibration receive signal is further different from the calibration transmit signal based on degradation of the calibration transmit signal as it travels from the destination to the first signal system. ### Claim 6 (depends on 1) The method of claim 1 wherein the calibration transmit signal is a ground penetrating radar signal. ### Claim 7 (depends on 1) The method of claim 1 wherein the calibration receive signal is received by a second signal system and then transmitted by the second signal system to the first signal system. ### Claim 8 A method performed by an electronics system associated with a first signal system having a radar antenna, the method comprising: receiving, via the radar antenna from a second signal system, a calibration receive signal corresponding to a calibration transmit signal transmitted by the second signal system via a radar antenna, the calibration receive signal being different from the calibration transmit signal based at least in part on degradation of the calibration transmit signal as it travels from the second signal system to the first signal system; identifying a transfer function that maps the calibration transmit signal to the calibration receive signal; identifying a pre-compensated transmit signal that when input to the transfer function outputs a desired receive signal; and transmitting, via the radar antenna to the second signal system, the pre-compensated transmit signal so that the second signal system can transmit the pre-compensated transmit signal via a radar antenna wherein a pre-compensated receive signal received via the radar antenna of the first signal system approximates the desired receive signal based at least in part on degradation of the pre-compensated transmit signal as it travels from the first signal system to the second signal system. ### Claim 9 (depends on 8) The method of claim 8 wherein the first signal system and the second signal system are part of a cellular communications network. ### Claim 10 A first signal system interfacing with a radar transmitter and receiver pair, the first signal system comprising: a component that controls transmitting a first signal via the radar transmitter; a component that controls receiving a second signal via the radar receiver, the second signal corresponding to a degradation of the first signal during transmission; a component that controls identifying a transfer function that maps the first signal to the second signal and identifies a third signal when input to the transfer function outputs a fourth signal; and a component that controls transmitting the third signal via the transmitter so that the third signal is received as an approximation of the fourth signal based on degradation that is similar to the degradation of the first signal. ### Claim 11 (depends on 10) The first signal system of claim 10 wherein the transmitter and receiver pair is a transceiver with a single antenna. ### Claim 12 (depends on 10) The first signal system of claim 10 wherein the transmitter and receiver pair includes a transmit antenna and a receive antenna. ### Claim 13 (depends on 10) The first signal system of claim 10 wherein the second signal is a reflection based on the first signal. ### Claim 14 (depends on 10) The first signal system of claim 10 wherein the first signal is a ground penetrating radar signal. ### Claim 15 (depends on 14) The first signal system of claim 14 wherein the second signal is received by a second signal system and then transmitted by the second signal system to the first signal system. ### Claim at position 16 16-32. (canceled)