Radar device

Patent metadata

Field	Value
Publication number	US-9664777-B2
Application number	US-201113881335-A
Country	US
Kind code	B2
Filing date	Nov 2, 2011
Priority date	Nov 16, 2010
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

Under control of a first transmission code controlling section, a first radar transmitting section periodically transmits a first radar transmission signal with a first transmission period based on a first transmission trigger signal produced after elapse of a first delay time period from reception of a predetermined synchronization establishment signal by a first transmission trigger signal producing section. Under control of a second transmission code controlling section, a second radar transmitting section periodically transmits a second radar transmission signal with a second transmission period similarly. In accordance with the first delay time period and the second delay time period, arrival times of interference signals from the first radar transmitting section and the second radar transmitting section are within transmission zones of the second radar transmission signal and the first radar transmission signal.

First claim

The invention claimed is:

1. A radar transmission method comprising:
generating a first transmission trigger signal after elapse of a first delay time period from reception of a predetermined synchronization establishment signal;
providing a first control signal to generate a first radar transmission signal for a first transmission period based on the first transmission trigger signal;
periodically generating and transmitting the first radar transmission signal from a first radar transmitter based on the first control signal;
generating a second transmission trigger signal after elapse of a second delay time period from reception of the predetermined synchronization establishment signal;
providing a second control signal to generate a second radar transmission signal for a second transmission period based on the second transmission trigger signal; and
periodically generating and transmitting the second radar transmission signal from a second radar transmitter based on the second control signal,
wherein in the providing of the second control signal to generate the second radar transmission signal, in accordance with the second delay time period, an adjustment time period Ts is adjusted to receive an arrival timing t 0 of an interference signal from the first radar transmitter within a transmission zone Tw of the second radar transmission signal, the adjustment time period Ts being a transmission timing of the second radar transmission signal; and
wherein in the periodically generating and transmitting of the second radar transmission signal, the second radar transmission signal is transmitted after elapse of the adjustment time period Ts from transmission of the first radar transmission signal.

2. The radar transmission method according to claim 1 , comprising:
calculating the arrival timing t 0 of the interference signal from the first radar transmitter based on a distance between a first radar unit that includes the first radar transmitter and a second radar unit that includes the second radar transmitter.

3. The radar transmission method according to claim 2 , wherein the calculating of the arrival timing t 0 of the interference signal from the first radar transmitter includes dividing a distance Rd between the first radar transmitter and the second radar transmitter by a light speed C; and
wherein the adjustment time period Ts from transmission of the first radar transmission signal is a time period which is longer than a time period that is obtained by subtracting the transmission zone Tw of the first radar transmission signal from the arrival timing t 0 of the interference signal from the first radar transmitter, and which is shorter than the arrival timing t 0 of the interference signal from the first radar transmitter.

4. The radar transmission method according to claim 1 , wherein the adjustment time period Ts corresponds to a half period of the first transmission period.

5. The radar transmission method according to claim 1 , comprising:
receiving the predetermined synchronization establishment signal.

6. The radar transmission method according to claim 5 , comprising:
generating a first transmission code having a first code length;
modulating the generated first transmission code; and
converting the modulated first transmission code to the first radar transmission signal, and periodically transmitting the first radar transmission signal with the first transmission period from a first transmission antenna.

7. The radar transmission method according to claim 6 , comprising:
generating a second transmission code having a second code length;
modulating the generated second transmission code; and
converting the modulated second transmission code to the second radar transmission signal, and periodically transmitting the second radar transmission signal with the second transmission period from a second transmission antenna.

8. The radar transmission method according to claim 7 , comprising:
receiving an interference signal from the second radar transmitter;
converting a signal of a reflected wave that is obtained by reflecting the first radar transmission signal from a target, and the interference signal from the second radar transmitter, to a base-band reception signal;
calculating a first correlation value between the base-band reception signal and a transmission signal that is identical with the first transmission code modulated by the first modulator;
averaging the calculated first correlation value during a predetermined number of first transmission periods; and
calculating an arrival distance of the target in accordance with a first average correlation value that is additionally averaged.

9. The radar transmission method according to claim 1 , comprising:
generating a first transmission code having a first code length;
generating a second transmission code having a second code length which is longer than the first code length;
selecting the generated first transmission code or second transmission code;
modulating the selected first transmission code or second transmission code; and
converting the modulated first transmission code or second transmission code to the first radar transmission signal.

10. The radar transmission method according to claim 9 ,
selectively switching a transmission antenna which transmits the converted first radar transmission signal, in accordance with the selected first transmission code or second transmission code.

11. The radar transmission method according to claim 9 , comprising:
generating a third transmission code having a third code length;
generating a fourth transmission code having a fourth code length which is longer than the third code length;
selecting the generated third transmission code or fourth transmission code;
modulating the selected third transmission code or fourth transmission code; and
converting the modulated third transmission code or fourth transmission code to the second radar transmission signal.

12. The radar transmission method according to claim 11 , comprising:
selectively switching a transmission antenna that transmits the converted second radar transmission signal, in accordance with the selected third transmission code or fourth transmission code.

13. The radar transmission method according to claim 1 , comprising:
generating a third transmission trigger signal after elapse of the first delay time period from the reception of the predetermined synchronization establishment signal;
controlling generation of a third radar transmission signal for the first transmission period based on the generated third transmission trigger signal;
periodically transmitting the generated third radar transmission signal from a third radar transmitter;
receiving the interference signal from the first radar transmitter;
receiving the interference signal from the second radar transmitter;
wherein in a case where a distance between the first radar transmitter and the second radar transmitter is approximately equal to a distance between the second radar transmitter and the third radar transmitter and is shorter than a distance between the first radar transmitter and the third radar transmitter, setting the adjustment time period Ts which causes the arrival timing t 0 of the interference signal from the first radar transmitter and an interference signal from the third radar transmitter to be within the transmission zone Tw of the second radar transmission signal; and
transmitting the second radar transmission signal from the second radar transmitter after elapse of the set adjustment time period Ts from the transmissions of the first radar transm

Assignees

• Kishigami Takaaki
• Nakagawa Yoichi
• Mukai Hirohito
• Panasonic Ip Man Co Ltd

Inventors

• Kishigami Takaaki
• Nakagawa Yoichi
• Mukai Hirohito

Classifications

• G01S2013/9316

  combined with communication equipment with other vehicles or with base stations · CPC title

• G01S7/2813

  Means providing a modification of the radiation pattern for cancelling noise, clutter or interfering signals, e.g. side lobe suppression, side lobe blanking, null-steering arrays (specially adapted to secondary radar systems G01S13/762; aerials or aerials systems H01Q21/29, H01Q25/00) · CPC title

• G01S13/931

  of land vehicles · CPC title

• G01S7/023 Primary

  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

• G01S13/284

  using coded pulses · CPC title