RADAR DEVICE

• US 20130162465A1
• Filed: 09/12/2011
• Published: 06/27/2013
• Est. Priority Date: 09/14/2010
• Status: Active Grant

• Current Assignee: PANASONIC AUTOMOTIVE SYSTEMS CO., LTD. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Mukai, Hirohito, Kishigami, Takaaki, Nakagawa, Yoichi
• Granted Patent: US 9,182,478 B2
• Time in Patent Office: Days
• US Class Current: 342/195
• 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 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 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 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.

2. The radar device according to claim 1, wherein the transmission signal position adjuster outputs a transmission signal in which transmission positions of the respective signal units of the intermittent signal are shifted so that timing is delayed or advanced in units of the time adjustment amount of the intermittent signal and a set of signal units having a pattern is repeated, the pattern ending when transmission timing becomes equal to the timing of the original intermittent signal.

3. The radar device according to claim 1, wherein the object detector generates a reception signal through sampling having an interval which is equal to the transmission position time adjustment amount according to information indicating transmission positions of the respective signal units of the intermittent signal on the basis of the digital signal generated by sampling the reception signal corresponding to the transmission signal with the AD converter.

4. The radar device according to claim 2, wherein the object detector generates a reception signal through sampling having an interval which is equal to the transmission position time adjustment amount by rearranging sampled values of transmission-position-shifted signal units of each pattern of the intermittent signal on the basis of the digital signal generated by sampling the reception signal corresponding to the transmission signal with the AD converter.

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 signal generator can vary the signal width of the intermittent signal to be generated, and generates an intermittent signal having a prescribed signal width according to measurement environment information supplied from the measurement environment detector; and

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

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 an intermittent signal having a first signal width if judging that the number of existing reflective objects is larger than or equal to a prescribed value, and generates an intermittent signal having a second signal width that is broader than the first signal width if 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 signal width of the intermittent signal is equal to the second signal width, the transmission signal position adjuster sets the time adjustment amount larger than when the signal width of the intermittent signal is equal to the first signal width.

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

a signal width controller that controls the signal width of the intermittent signal,

wherein the signal generator can vary the signal width of the intermittent signal to be generated, and generates the intermittent signal having the prescribed signal width according to a control signal supplied from the signal width controller; and

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