US 11,994,611 B2
Frequency and time offset modulation (FANTOM) chirp MIMO automotive radar with N-path notch filter
Douglas Alan Garrity, Gilbert, AZ (US); Ryan Haoyun Wu, San Jose, CA (US); and Maik Brett, Taufkirchen (DE)
Assigned to NXP B.V., Eindhoven (NL)
Filed by NXP B.V., Eindhoven (NL)
Filed on Oct. 1, 2021, as Appl. No. 17/491,596.
Prior Publication US 2023/0128469 A1, Apr. 27, 2023
Int. Cl. G01S 7/292 (2006.01); G01S 7/35 (2006.01)
CPC G01S 7/292 (2013.01) [G01S 7/354 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for operating a radar system, comprising:
generating a reference signal comprising a sequence of waveforms at a transmitter module;
generating a plurality of frequency and time offset modulation signals from the reference signal for a corresponding plurality of N transmitters of the radar system, wherein each transmitter is associated with a distinct frequency and time offset modulation signal;
transmitting the plurality of frequency and time offset modulation signals as N radio-frequency encoded transmit signals from the N transmitters at the radar system;
receiving, at a receiving antenna of a receiver module at the radar system, a target return signal reflected from the N radio-frequency encoded transmit signals;
mixing the target return signal with the reference signal at the receiver module to produce an intermediate frequency signal;
filtering the intermediate frequency signal with a bank of one or more notch filters to produce a filtered intermediate frequency signal, where the bank of one or more notch filters is clocked with a sampling clock frequency FCLOCK to control harmonic notch frequencies of the bank of one or more notch filters;
converting the filtered intermediate frequency to a digital signal with an analog-to-digital converter at the receiver module that is clocked with a sampling clock frequency of at least FCLOCK; and
processing the digital signal to generate a range spectrum comprising N segments that correspond, respectively, to the N radio frequency encoded transmit signals transmitted over the N transmitters.