RADAR APPARATUS AND SIGNAL PROCESSING METHOD

• US 20140292559A1
• Filed: 12/11/2013
• Published: 10/02/2014
• Est. Priority Date: 03/29/2013
• Status: Active Grant

• Current Assignee: Fujitsu Ten Limited (DENSO Corporation)
• Original Assignee: Fujitsu Ten Limited (DENSO Corporation)
• Inventors: ASANUMA, Hisateru, ISHIMORI, Hiroyuki
• Granted Patent: US 9,575,167 B2
• Time in Patent Office: Days
• US Class Current: 342/133
• CPC Class Codes: G01S 13/06 Systems determining position data of a target
• CPC Class Codes: G01S 13/345 using triangular modulation
• CPC Class Codes: G01S 13/536 using transmission of continuous unmodulated waves, amplitude-, frequency-, or phase-modulated waves
• CPC Class Codes: G01S 13/726 Multiple target tracking
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/462 using multipath signals
• CPC Class Codes: G01S 2013/93271 in the front of the vehicles

Abstract

There is provided a radar apparatus capable of emitting a transmission wave relating to a transmitting signal which is frequency-modulated, and receiving a reflection wave coming from a target at which the transmission wave is reflected as a receiving signal, to derive at least position information of the target based on the receiving signal. A deriving unit derives a fluctuation value of a signal level relating to the receiving signal for a stationary target among the targets. A calculating unit calculates a fluctuation integrated value integrated by the fluctuation value. A judging unit judges the stationary target as a target other than a control subject if the fluctuation integrated value is below a predetermined threshold.

Claims

1. A radar apparatus capable of emitting a transmission wave relating to a transmitting signal which is frequency-modulated, and receiving a reflection wave coming from a target at which the transmission wave is reflected as a receiving signal, to derive at least position information of the target based on the receiving signal, the radar apparatus comprising:

a deriving unit configured to derive a fluctuation value of a signal level relating to the receiving signal for a stationary target among the targets;

a calculating unit configured to calculate a fluctuation integrated value integrated by the fluctuation value; and

a judging unit configured to judge the stationary target as a target other than a control subject if the fluctuation integrated value is below a predetermined threshold.

2. The radar apparatus according to claim 1, wherein the signal level relating to the receiving signal is a signal level of an angular signal.

3. The radar apparatus according to claim 1, wherein the fluctuation value is a value derived from a maximum value and a minimum value of the signal level.

4. The radar apparatus according to claim 3, wherein the deriving unit derives the fluctuation value from the maximum value to the minimum value if the stationary target exists at a position which is above a predetermined distance, and derives the fluctuation value from the minimum value to the maximum value if the stationary target exists at a position which is below the predetermined distance.

5. The radar apparatus according to claim 1, wherein the judging unit is configured to easily judge the stationary target as a target other than the control subject if a moving target exists at a distance closer than the stationary target.

6. The radar apparatus according to claim 1, wherein the calculating unit increases an integration rate of the fluctuation value as the signal level is high.

7. The radar apparatus according to claim 1, further comprising a target judging unit configured to judge whether or not there is a diverged target which is other stationary target belonging to the same object as the stationary target,

wherein the judging unit does not perform the judgment if the diverged target exists.

8. The radar apparatus according to claim 1, further comprising a continuous target judging unit configured to judge whether or not there is a continuous stationary target which continuously exists in a traveling direction of a vehicle mounted with the radar apparatus at a side of a traffic lane on which the vehicle is traveling,

wherein if the continuous stationary target exists, the judging unit does not perform the judgment when the stationary target has a substantially symmetrical positional relation to other stationary target with respect to the continuous stationary target.

9. The radar apparatus according to claim 7, further comprising a continuous target judging unit configured to judge whether or not there is a continuous stationary target which continuously exists in a traveling direction of a vehicle mounted with the radar apparatus at a side of a traffic lane on which the vehicle is traveling,

wherein the target judging unit changes a judgment condition of the diverged target if the continuous stationary target exists.

10. A signal processing method of emitting a transmission wave relating to a transmitting signal which is frequency-modulated, and receiving a reflection wave coming from a target at which the transmission wave is reflected as a receiving signal, to derive at least position information of the target based on the receiving signal, the signal processing method comprising:

deriving a fluctuation value of a signal level relating to the receiving signal for a stationary target among the targets;

calculating a fluctuation integrated value integrated by the fluctuation value; and

judging the stationary target as a target other than a control subject if the fluctuation integrated value is below a predetermined threshold.