US 12,422,522 B2
Real-time detection and parameter estimation of radar signals in time varying noisy environments
Van Long Do, Ha Noi (VN); Tran Minh Nguyen, Ha Noi (VN); Van Tho Nguyen, Ha Noi (VN); Anh Hung Hoang, Ha Noi (VN); Trung Duc Dang, Ha Noi (VN); Thai Binh Nguyen, Ha Noi (VN); and Manh Linh Nguyen, Ha Noi (VN)
Assigned to VIETTEL GROUP, Ha Noi (VN)
Filed by VIETTEL GROUP, Ha Noi (VN)
Filed on May 18, 2022, as Appl. No. 17/747,725.
Claims priority of application No. 1-2021-04766 (VN), filed on Jul. 30, 2021.
Prior Publication US 2024/0319336 A1, Sep. 26, 2024
Int. Cl. G01S 7/41 (2006.01); G01S 7/288 (2006.01); G01S 7/292 (2006.01); G01S 7/35 (2006.01)
CPC G01S 7/414 (2013.01) [G01S 7/2886 (2021.05); G01S 7/2925 (2013.01); G01S 7/354 (2013.01)] 9 Claims
OG exemplary drawing
 
2. A method for detecting radar signals and estimating their intra-pulse parameters in time-varying noisy environments, the said method comprising the steps of:
performing pre-processing tasks on input wideband IQ samples;
estimating a noise floor level hxn from magnitude-squared envelopes;
calculating detection statistics for rising and falling edge decision;
detecting a rising edge of radar pulses (i.e., a presence of radar pulses);
estimating a time of arrival (TOA) of radar pulses;
detecting a falling edge of radar pulses;
estimating a time of departure (TOD) of radar pulses;
calculating a pulse width (PW) of radar pulses;
estimating an amplitude (AMP) of radar pulses;
estimating a center frequency (FC) and bandwidth (BW) of radar pulses;
wrapping intra-pulse parameters into pulse descriptor words (PDWs),
wherein the said step of calculating detection statistics for rising and falling edge decision comprises the following sub-steps:
estimating an expectation μn of a distribution of random noises;
estimating a standard deviation σn of the distribution of random noises;
estimating a tentative pulse amplitude μx for the magnitude-squared envelopes;
calculating a log-likelihood ratio (LLR) sn between a distribution of tentative intra-pulse samples and a distribution of random noises;
calculating a detection statistic gn for rising edge decision from the said LLR sn;
calculating a detection statistic dn for falling edge decision from the said LLR sn.