Radar measuring device and method with dual radar signal generation

Patent metadata

Field	Value
Publication number	US-12436258-B2
Application number	US-202217870166-A
Country	US
Kind code	B2
Filing date	Jul 21, 2022
Priority date	Jul 29, 2021
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

Radar measuring device including:
a first generator of a first periodic radar signal whose frequency varies linearly, over at least one portion T ramp of a period T in , in a frequency band B; a transmit antenna coupled to an output of the first generator and configured to transmit the first radar signal; a second generator of a second periodic radar signal whose frequency varies linearly, over said portion T ramp of the period T in , in the frequency band B, which is generated with the same start-up phase as the first radar signal and having, relative to the first radar signal, a configurable delay τ mix ; a receive antenna configured to receive at least one echo of the first radar signal; a mixer comprising a first input coupled to the receive antenna and a second input coupled to an output of the second generator.

First claim

The invention claimed is:

1. A radar measuring device, comprising:
a first generator of a first periodic radar signal whose frequency varies linearly, over at least one portion T ramp of a period, in a frequency band;
a transmit antenna coupled to an output of the first generator and configured to transmit the first radar signal;
a second generator of a second periodic radar signal (1) whose frequency varies linearly, over said portion T ramp of the period, in the frequency band, (2) which is generated with a constant phase or a same start-up phase as the first radar signal, and (3) has, relative to the first radar signal, a configurable delay τ mix ;
a receive antenna configured to receive at least one echo of the first radar signal; and
a mixer comprising a first input coupled to the receive antenna and a second input coupled to an output of the second generator, wherein:
the first generator includes a first polar modulator configured to receive, on a first input, a first periodic signal to be frequency modulated, receive, on a second input, a first control signal comprising a digital sequence of frequency samples, receive, on a third input, a clock signal, and perform a modulation of the first periodic signal by the first control signal at a frequency of the clock signal; and
the second generator includes a second polar modulator configured to receive, on a first input, the first periodic signal to be frequency modulated, receive, on a second input, a second control signal comprising said digital sequence of frequency samples delayed by the configurable delay τ mix , which is equal to an integer number of periods of the clock signal, receive, on a third input, the clock signal, and perform a modulation of the first periodic signal by the second control signal at the frequency of the clock signal.

2. The radar measuring device according to claim 1 , wherein an output of the first polar modulator is coupled to an input of a first frequency multiplier, the first radar signal corresponding to the signal to be output from the first frequency multiplier, and
wherein an output of the second polar modulator is coupled to a input of a second frequency multiplier, the second radar signal corresponding to the signal to be output from the second frequency multiplier.

3. The radar measuring device according to claim 1 , further comprising, coupled to an output of the mixer, a high pass filter, which is coupled in series to a variable cut-off frequency and a gain filter.

4. The radar measuring device according to claim 1 , further comprising an analog digital converter comprising an input that is coupled to an output of a variable cut-off frequency and a gain filter.

5. A radar measuring method implemented with at least one radar measuring device according to claim 1 , the method comprising:
selecting a first value of the configurable delay τ mix , of a first value B 1 of the frequency band and of a first T ramp value; and
a first radar measuring step implemented with the radar measuring device, which is configured with the first value of the configurable delay τ mix and the first value B 1 .

6. The radar measuring method according to claim 5 , wherein at least one of:
the first value of the configurable delay τ mix is equal to 0;
the first value B 1 is between 200 MHz and 2 GHz; or
the first T ramp value is between 1 μs and 10 μs.

7. The radar measuring method according to claim 5 , further comprising, after the implementation of the first radar measurement step:
measuring, in a spectrum of the output signal of the radar measuring device obtained during the first radar measurement step, one or more frequency peaks f IF,k , k being an integer greater than or equal to 1, each representative of a presence of at least one reflector at a given distance from the radar measuring device;
calculating, for the or each of the frequency peaks f IF,k , d an estimate of said given distance according to the equation

=

-

f

IF
,

k
·

⁢

T
ramp

B
1

·

c
2

,

with c corresponding to the speed of light in a vacuum;
selecting a second value B 2 >B 1 of the frequency band;
calculating one or more second values τ mix,k of the configurable delay τ mix according to the equation

τ

mix
,
k

=

2

c

-

1

2
⁢

B
2

;

and
one or more second radar measuring steps, each implemented with the radar measuring device configured with the or one of the second values τ mix,k and the second value B 2 .

8. The radar measuring method according to claim 7 , wherein the second value B 2 is between 2 GHz and 4 GHz.

9. The radar measuring method according to claim 7 , further comprising, after the implementation of the one or more second radar measuring steps:
measuring, in the spectrum of the or each output signal of the radar measuring device obtained during the or each of the one or more second radar measurement steps, one or more frequency peaks f IF,k ;
calculating, for the or each of the frequency peaks f IF,k , an estimate of said given distance according to the equation

=

-

f

IF
,

k
·

⁢

T
ramp

B
2

·

c
2

selecting a third value B 3 >B 2 of the frequency ba

Assignees

• Commissariat Energie Atomique

Inventors

• Antide Etienne
• Zarudniev Mykhailo
• Lachartre David

Classifications

• G01S7/354

  Extracting wanted echo-signals (Doppler systems G01S13/50) · CPC title

• G01S13/70

  for range tracking only · CPC title

• G01S13/40

  wherein the frequency of transmitted signal is adjusted to give a predetermined phase relationship · CPC title

• G01S7/415

  Identification of targets based on measurements of movement associated with the target · CPC title

• G01S7/35

  Details of non-pulse systems · CPC title