Radar device

• US 9,182,478 B2
• Filed: 09/12/2011
• Issued: 11/10/2015
• Est. Priority Date: 09/14/2010
• Status: Active Grant

• Current Assignee: Panasonic Automotive Systems Company of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Mukai, Hirohito, Kishigami, Takaaki, Nakagawa, Yoichi
• Primary Examiner(s): Gregory, Bernarr
• Application Number:
  US13/818,194
• Publication Number:
  US 20130162465A1
• Time in Patent Office: 1,520 Days
• Field of Search: 342/27, 342/28, 342 82-103, 342/118, 342134-145, 342/175, 342/195, 342/196, 342202-204, 705/1.1
• US Class Current: 1/1
• CPC Class Codes: G01S 13/103 particularities of the measurement of the distance G01S13/12, G01S13/14, G01S13/16, G01S13/18 and G01S13/20 take precedence
• CPC Class Codes: G01S 13/106 using transmission of pulses having some particular characteristics G01S13/12, G01S13/22, G01S13/24, G01S13/26, G01S13/28 and G01S13/30 take precedence
• CPC Class Codes: G01S 7/282 Transmitters
• CPC Class Codes: G01S 7/285 Receivers

Abstract

A radar device includes a signal generator that generates an intermittent signal having a prescribed signal width and signal interval, a transmission signal position adjuster that outputs a transmission signal while adjusting positions of the intermittent signal on the time axis, an RF transmitter that transmits the transmission signal, an RF receiver that receives a reception signal including reflection waves reflected from an object in a measurement subject space, an AD converter that converts the reception signal into a digital signal, and an object detector that detects the object based on the reception signal. The transmission signal position adjuster outputs a transmission signal in which positions of respective signal units of the intermittent signal on the time axis are adjusted in units of a time adjustment amount that is shorter than a sampling interval of the AD converter.

Claims

1. A radar device comprising:

a pulse generator that generates a pulse sequence having a prescribed pulse width and pulse interval;

a transmission pulse position adjuster that outputs a transmission signal while adjusting positions of the pulse sequence on the time axis;

an RF transmitter that transmits the transmission signal to a measurement subject space in the form of radio waves;

an RF receiver that receives, from the measurement subject space, a reception signal including reflection waves reflected from an object in the measurement subject space;

an AD converter that converts the reception signal into a digital signal; and

an object detector that detects the object on the basis of the reception signal,

wherein

the transmission pulse position adjuster adjusts a transmission timing of each pulse of the pulse sequence using an amount of a transmission time adjustment that is shorter than a sampling interval of the AD converter.

2. The radar device according to claim 1, wherein the transmission pulse position adjuster outputs a transmission signal in which transmission positions of the each pulse of the pulse sequence are delayed or advanced using the amount of the transmission time adjustment, and the pulse sequence has one or more pulse groups, each of the one or more pulse groups ending when the transmission timing becomes equal to the timing of the original pulse sequence.

3. The radar device according to claim 2, wherein the object detector generates a reception signal from the digital signal which is rearranged the order of the pulse groups, a sampling interval which is equal to the adjusted transmission timing according to the amount of the transmission time adjustment of the each pulse.

4. The radar device according to claim 1, wherein the object detector generates a reception signal from the digital signal using a sampling interval which is equal to the adjusted transmission timing according to the amount of the transmission time adjustment of the each pulse.

5. The radar device according to claim 1, further comprising:

a measurement environment detector that detects a measurement environment of the reception signal,

wherein the pulse generator adjusts the pulse width to be generated, and generates a pulse sequence having a prescribed pulse width according to measurement environment information supplied from the measurement environment detector; and

wherein the transmission pulse position adjuster varies the amount of the time adjustment according to the pulse width.

6. The radar device according to claim 5, wherein the measurement environment detector outputs, as the measurement environment information, feature information relating to the number of reflective objects existing in the measurement environment.

7. The radar device according to claim 6, wherein the signal generator generates a pulse sequence having a first pulse width when judging that the number of existing reflective objects is larger than or equal to a prescribed value, and generates a pulse sequence having a second pulse width that is broader than the first pulse width when judging that the number of existing reflective objects is smaller than the prescribed value.

8. The radar device according to claim 7, wherein when the pulse width is equal to the second pulse width, the transmission pulse position adjuster sets the amount of time adjustment larger than when the pulse width is equal to the first pulse width.

9. The radar device according to claim 1, further comprising:

a pulse width controller that controls the pulse width,

wherein the pulse generator adjust the pulse width to be generated, and generates the pulse sequence having the prescribed pulse width according to a control signal supplied from the pulse width controller; and

wherein the transmission pulse position adjuster adjusts the amount of time adjustment according to the pulse width.