Microwave radar and unmanned aerial vehicle

Patent metadata

Field	Value
Publication number	US-2025035739-A1
Application number	US-202418893408-A
Country	US
Kind code	A1
Filing date	Sep 23, 2024
Priority date	Nov 21, 2018
Publication date	Jan 30, 2025
Grant date	—

Abstract

A microwave radar includes an antenna device and a radar controller in communication with the antenna device, and configured to: control the antenna device to transmit a microwave transmission signal and obtain a received signal, obtain an intermediate frequency signal mixed by a frequency of the microwave transmission signal and the received signal to the radar controller, and determine whether the received signal is an interference signal based on the intermediate frequency signal, including: determining change information of a signal frequency and a signal amplitude of the intermediate frequency signal based on the intermediate frequency signal, and determining whether the received signal is the interference signal based on the change information of the signal frequency and the signal amplitude of the intermediate frequency signal. The microwave transmission signal and the received signal both are trapezoidal modulation waveforms.

First claim

What is claimed is:

1 . A microwave radar comprising:
an antenna device; and a radar controller in communication with the antenna device, and configured to:
control the antenna device to transmit a microwave transmission signal and obtain a received signal, the microwave transmission signal and the received signal both being trapezoidal modulation waveforms, and one cycle of the trapezoidal modulation waveform including a frequency rising part, a frequency falling part, and a fixed frequency part;
obtain an intermediate frequency signal mixed by a frequency of the microwave transmission signal and the received signal to the radar controller, and determine whether the received signal is an interference signal based on the intermediate frequency signal, including:
determining change information of a signal frequency and a signal amplitude of the intermediate frequency signal based on the intermediate frequency signal; and
determining whether the received signal is the interference signal based on the change information of the signal frequency and the signal amplitude of the intermediate frequency signal.

2 . The microwave radar of claim 1 , wherein the radar controller is further configured to:
determine the received signal is the interference signal in response to a change state of the signal frequency of the received signal being gradually decreasing and then gradually increasing, and a change state of the signal amplitude being gradually increasing and then gradually decreasing.

3 . The microwave radar of claim 1 , wherein the radar controller is further configured to:
obtain signal amplitude information of N sampling points of the intermediate frequency signal; select P extreme value points based on the signal amplitude information of the N sapling points, P being a positive integer greater than or equal to 2 and less than N; and determine whether the received signal is the interference signal based on index values of the P extreme value points.

4 . The microwave radar of claim 3 , wherein the radar controller is further configured to:
eliminate the interference signal in response to determining that the received signal is the interference signal.

5 . The microwave radar of claim 4 , wherein the radar controller is further configured to:
determine a maximum amplitude point and a minimal amplitude point in the N sampling points based on the amplitude information of the N sampling points of the intermediate frequency signal, calculate an amplitude difference between the maximum amplitude point and the minimal amplitude point, and record the amplitude difference as a first difference A; obtain the P extreme value points whose amplitude difference with adjacent extreme value points is greater than A/2 in the N sampling points; and record the index value of each of the P extreme value points to obtain P index values, P being a positive integer greater than or equal to 2 and less than N.

6 . The microwave radar of claim 5 , wherein the radar controller is further configured to:
determine whether there are at least two target index values satisfying a predetermined time domain characteristic conditions in the P index values; and determine the received signal is a burst interference signal within a time period corresponding to a fluctuating frequency in response to determining there are at least two target index values satisfying the predetermined time domain characteristic conditions in the P index values.

7 . The microwave radar of claim 6 , wherein the radar controller is further configured to:
obtain all extreme points in the N sampling points, calculate the amplitude difference between every two adjacent extreme points, and record the amplitude of the extreme point whose amplitude difference is greater than a predetermined difference and the index value of the extreme point whose amplitude difference is greater than the predetermined difference as a first set; calculate an absolute value of the amplitude difference of every two adjacent extreme points in the first set and an index value difference of every two adjacent extreme points in the first set, and record the absolute value of the amplitude difference and an absolute value of the index value difference as a second set; and obtain the extreme point in the second set where the absolute value of the amplitude difference is greater than A/2, and obtain first P extreme value points in a descending order of the absolute value of the amplitude difference.

8 . The microwave radar of claim 7 , wherein the radar controller is further configured to:
combine the P index values in pairs, use a smaller index value of the combined two index values as a left boundary index value, and use a larger index value of the combined two index values as a right boundary index value; for each combination, calculate the index value difference between the right boundary index value and the left boundary index value, select M 1 extreme points forward from the left boundary index value based on an order of a distance between the index value and the left boundary index value from small to large, select M 2 extreme points backward from the right boundary index value based on the order of a distance between the index value and the right boundary index value from small to large, M 1 and M 2 both being positive integers; determine whether the index value difference between the right boundary index value and the left boundary index value satisfying a first predetermined time domain characteristic condition, and determine whether the M 1 extreme value points and the M 2 extreme value points satisfying a second predetermined time domain characteristic condition; and use the two index values as two target index values in response to the index value difference between the right boundary index value and the left boundary index value satisfying the first predetermined time domain characteristic condition, and the M 1 extreme value points and the M 2 extreme value points satisfying the second predetermined time domain characteristic condition; wherein:
the first predetermined time domain characteristic condition includes that the index value difference between the right boundary index value and the left boundary index value is less than a first predetermined interval value; and
the second predetermined time domain characteristic condition includes that:
the index value difference of the M 1 extreme points is less than a second predetermined interval value, and the index value difference of the M 2 extreme points is less than the second predetermined interval value; and
an absolute mean value of the amplitude difference of the M 1 extreme points is less than a half of a maximum absolute value of the amplitude difference in the second set, and an absolute mean value of the amplitude difference of the M 2 extreme points is less than a half of the maximum absolute value of the amplitude difference in the second set.

9 . The microwave radar of claim 8 , wherein the radar controller is further configured to:
use a middle position of the two target index values as a center index value in response to the target index value satisfying the predetermined time domain characteristic condition being two; in response to the target index value satisfying the predetermined time domain characteristic condition being greater than two, in all the combinations satisfying the condition, select the combination with a largest absolute value of the amplitude difference corresponding to the extreme point as a target index value combination, and use the middle position of the two target index values corresponding to the target index value combination as the center index value; exten

Assignees

• Sz Dji Technology Co Ltd

Inventors

• Li Xun
• Wang Chunming

Classifications

• G05D1/606

  Compensating for or utilising external environmental conditions, e.g. wind or water currents (station keeping G05D1/611) · CPC title

• G01S7/354

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

• G01S13/933

  of aircraft or spacecraft · CPC title

• G05D1/106

  Change initiated in response to external conditions, e.g. avoidance of elevated terrain or of no-fly zones · CPC title

• G01S7/023

  Interference mitigation, e.g. reducing or avoiding non-intentional interference with other HF-transmitters, base station transmitters for mobile communication or other radar systems, e.g. using electro-magnetic interference [EMI] reduction techniques (auxiliary means for detecting or identifying radar signals or the like G01S7/021; means for anti-jamming G01S7/36) · CPC title