US 11,719,786 B2
Asynchronous, coherent, radar transmitter-receiver system
Kenneth I. Ranney, Monrovia, MD (US); Kyle A. Gallagher, Silver Spring, MD (US); Daniel T. Galanos, Silver Spring, MD (US); Abigail S. Hedden, Vienna, VA (US); and Roger P. Cutitta, Westminster, MD (US)
Assigned to The United States of America as represented by the Secretary of the Army, Washington, DC (US)
Filed by U.S. Army Combat Capabilities Development Command, Army Research Laboratory, Adelphi, MD (US)
Filed on Feb. 11, 2021, as Appl. No. 17/173,680.
Claims priority of provisional application 62/981,102, filed on Feb. 25, 2020.
Prior Publication US 2021/0263132 A1, Aug. 26, 2021
Int. Cl. G01S 7/288 (2006.01); G01S 13/00 (2006.01); G01S 7/292 (2006.01)
CPC G01S 7/288 (2013.01) [G01S 7/292 (2013.01); G01S 13/003 (2013.01); G01S 7/2883 (2021.05)] 19 Claims
OG exemplary drawing
 
1. A radar system comprising:
at least one radio receiver comprising:
an antenna configured to receive RF data including both the direct-path RF signal transmitted from a radio transmitter and a reflected RF signal when the transmitted RF signal is reflected from a target;
a memory configured to store the predetermined RF waveform profile data used by the radio transmitter to generate and transmit the RF signal;
a timing unit to provide timing;
a matched filter application configured to generate and apply a matched filter for identifying RF signal signatures in RF data; and
one or more processors configured to:
(i) analyze the received RF data to identify multiple, repeated, individual RF signals corresponding to the direct-path transmitted RF signal;
(ii) split the identified RF signals corresponding to the direct-path transmitted RF signal into a plurality of repeating units each having an interval time;
(iii) create a matched filter using the stored predetermined transmit waveform profile data in the memory and apply the matched filter to each of repeating units to provide (a) a plurality of direct-path transmitted RF signal arrival times; and (b) a plurality of reflected RF signal arrival times;
(iv) adjust relative arrival times and phases of the repeating units of the direct-path transmitted RF signal in which the one or more processors are configured to:
(1) determine the time and phase within the first repeating unit of the first arrival of the direct-path transmitted RF signal;
(2) set the time and phase for the determined first arrival time as a reference time and phase, respectively; and
(3) adjust the times and phases of the first arrivals of the identified direct-path transmitted RF signal and reflected RF signal within each of the remaining repeating units so that the direct-path transmitted signal matches the reference time and phase; and
(v) generate radar data from the reflected RF signal further using the adjusted times and phases for arrival times of the repeating units of the direct-path transmitted RF signal.