Self-calibration method of switched array antenna radar

Patent metadata

Field	Value
Publication number	US-10965025-B2
Application number	US-201815901161-A
Country	US
Kind code	B2
Filing date	Feb 21, 2018
Priority date	Apr 11, 2017
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

Disclosed is a self-calibration method and apparatus for an array antenna system. According to an embodiment of the present disclosure, a correction method of an array antenna system includes: deriving, at a first time, a correction factor Ri,j for a path connecting an i-th (i is an integer equal to or greater than one and equal to or less than m) transmission antenna and a j-th (j is an integer equal to or greater than one and equal to or less than n) reception antenna; deriving, at a second time, a calibration factor {circumflex over (Q)}i,j for the path connecting the i-th transmission antenna and the j-th reception antenna; and performing, based on the {circumflex over (Q)}i,j, calibration on the path connecting the i-th transmission antenna and the j-th reception antenna.

First claim

What is claimed is:

1. A correction method of an array antenna system including m transmission antennas and n reception antennas, wherein m and n are integers greater than one, the correction method comprising:
deriving, at a first time, a correction factor R i,j for a path connecting an i-th transmission antenna and a j-th reception antenna, wherein i is an integer equal to or greater than one and equal to or less than m, and j is an integer equal to or greater than one and equal to or less than n;
deriving, at a second time, a calibration factor {circumflex over (Q)} i,j for the path connecting the i-th transmission antenna and the j-th reception antenna; and
performing, based on the calibration factor {circumflex over (Q)} i,j , calibration on the path connecting the i-th transmission antenna and the j-th reception antenna,
wherein the deriving of the correction factor R i,j comprises:
deriving a first reference inverse system response Q ref for a reference path;
deriving an inverse system response Q i,j for the path connecting the i-th transmission antenna and the j-th reception antenna; and
deriving the correction factor R i,j based on the first reference inverse system response Q ref and the inverse system response Q i,j .

2. The correction method of claim 1 , wherein the correction factor R i,j has a time-invariant constant value.

3. The correction method of claim 1 , wherein the deriving of the correction factor R i,j is performed only once during operation of the array antenna system.

4. The correction method of claim 1 , wherein the deriving of the calibration factor {circumflex over (Q)} i,j comprises:
deriving a second reference inverse system response {circumflex over (Q)} ref for the reference path; and
deriving the calibration factor {circumflex over (Q)} i,j based on the correction factor R i,j and the second reference inverse system response {circumflex over (Q)} ref .

5. The correction method of claim 1 , wherein the second time is a time subsequent to the first time.

6. The correction method of claim 1 , wherein the deriving of the calibration factor {circumflex over (Q)} i,j is periodically performed at predetermined time intervals.

7. The correction method of claim 1 , wherein the correction factor R i,j or the calibration factor {circumflex over (Q)} i,j is derived for all paths connecting one of the m transmission antennas and one of the n reception antennas.

8. The correction method of claim 1 , wherein the reference path is a path connecting a transmission reference port of a transmitter antenna switch for selecting one of the m transmission antennas and a reception reference port of a receiver antenna switch for selecting one of the n reception antennas.

9. The correction method of claim 8 , wherein the reference path or the path connecting the i-th transmission antenna and the j-th reception antenna is selected based on a time-division-multiplexing (TDM) control signal input to the transmitter antenna switch and the receiver antenna switch.

10. A calibration apparatus for an array antenna system, the calibration apparatus comprising:
m transmission antennas, wherein m is an integer equal to or greater than one;
n reception antennas, wherein n is an integer equal to or greater than one; and
a signal processing unit is configured to:
derive, at a first time, a correction factor R i,j for a path connecting an i-th transmission antenna and a j-th reception antenna, wherein i is an integer equal to or greater than one and equal to or less than m, and j is an integer equal to or greater than one and equal to or less than n;
derive, at a second time, a calibration factor {circumflex over (Q)} i,j for the path connecting the i-th transmission antenna and the j-th reception antenna; and
perform, based on the calibration factor {circumflex over (Q)} i,j , calibration on the path connecting the i-th transmission antenna and the j-th reception antenna,

wherein the signal processing unit is further configured to derive the correction factor R i,j by deriving a first reference inverse system response Q ref for a reference path, deriving an inverse system response Q i,j for the path connecting the i-th transmission antenna and the j-th reception antenna, and deriving the correction factor R i,j based on the first reference inverse system response Q ref and the inverse system response Q i,j .

11. The calibration apparatus of claim 10 , wherein the correction factor R i,j has a time-invariant constant value.

12. The calibration apparatus of claim 10 , wherein the deriving of the correction factor R i,j is performed only once during operation of the array antenna system.

13. The calibration apparatus of claim 10 , wherein the signal processing unit is further configured to:
derive a second reference inverse system response {circumflex over (Q)} ref for the reference path, and
derive the calibration factor {circumflex over (Q)} i,j based on the correction factor R i,j and the second reference inverse system response {circumflex over (Q)} ref .

14. The calibration apparatus of claim 10 , wherein the second time is a time subsequent to the first time.

15. The calibration apparatus of claim 10 , wherein the deriving of the calibration factor {circumflex over (Q)} i,j is periodically performed at predetermined time intervals.

16. The calibration apparatus of claim 10 , wherein the correction factor R i,j or the calibration factor {circumflex over (Q)} i,j is derived for all paths connecting one of the m transmission antennas and one of the n reception antennas.

17. The calibration apparatus of claim 10 , wherein the reference path is a path connecting a transmission reference port of a transmitter antenna switch for selecting one of the m transmission antennas and a reception reference port of a receiver antenna switch for selecting one of the n reception antennas.

18. The calibration apparatus of claim 17 , wherein the reference path or the path connecting the i-th transmission antenna and the j-th reception antenna is selected based on a time-division-multiplexing (TDM) control signal input to the transmitter antenna switch and the receiver antenna switch.

19. A correction method of an array antenna system including m transmission antennas and n reception antennas, wherein m and n are integers greater than one, the correction method comprising:
deriving, at a first time, a correction factor R i,j for a path connecting an i-th transmission antenna and a j-th reception antenna, wherein i is an integer equal to or greater than one and equal to or less than m, and j is an integer equal to or greater than one and equal to or less than n;
deriving, at a second time, a calibration factor {circumflex over (Q)} i,j for the path connecting the i-th transmission antenna and the j-th reception antenna; and
performing, based on the calibration factor {circumflex over (Q)} i,j , calibration on the path connecting the i-th transmission antenna and the j-th reception antenna,
wherein the deriving of the calibration factor {circumflex over (Q)} i,j comprises:
deriving a reference inverse system response {circumflex over (Q)} ref for a reference path; and
deriving the calibration factor {circumflex over (Q)} i,j based on the correction factor R i,j and the reference inverse system response {circumflex over (Q)} ref .

20. A calibration apparatus for an array antenna system, the calibration apparatus comprising:
m transmission antennas, wherein m is an integer equal t

Assignees

• Electronics And Telecommunications Res Insitute
• Electronics & Telecommunications Res Inst

Inventors

• Kim Dong Kyoo

Classifications

• G01S7/4004 Primary

  of parts of a radar system · CPC title

• G01S7/4065

  involving a delay line · CPC title

• G01S13/888

  through wall detection · CPC title

• G01S7/4052

  by simulation of echoes · CPC title

• G01S13/931

  of land vehicles · CPC title