Multi-lane vehicle detection apparatus

• US 20090243890A1
• Filed: 03/28/2008
• Published: 10/01/2009
• Est. Priority Date: 03/28/2008
• Status: Active Grant

• Current Assignee: National Chiao Tung University (Government of The Republic of China)
• Original Assignee: Institute of Transportation MOTC
• Inventors: CHANG, Chi-Ho, TZUANG, Ching-Kuang C.
• Granted Patent: US 7,884,740 B2
• Time in Patent Office: Days
• US Class Current: 340/934
• CPC Class Codes: G08G 1/015 with provision for distinguishing between two or more types of vehicles, e.g. between motor-cars and cycles
• CPC Class Codes: G08G 1/042 using inductive or magnetic detectors
• CPC Class Codes: G08G 1/052 with provision for determining speed or overspeed speed measuring in general G01P

Abstract

A vehicle detection apparatus adopting microwave sensing schemes for performing the multi-lane vehicle detection is provided in the present invention. According to the present invention, the signal-to-noise ratio (SNR) of the detected reflecting wave is varied within an inconsiderable range so that the provided apparatus may exhibit a unique property which is adoptable for the multi-lane vehicle detection and the precision is unachievable by the existing detectors.

Claims

1. A detecting apparatus for multi-lane vehicle detection, comprising:

a radio-frequency transceiving unit comprising a signal input and a s signal output and generating a difference-frequency signal;

at least two antennas of leakage-wave mode arranged closely to each other and coupled to said signal input and said signal output respectively; and

an intermediate-frequency and digital signal processing unit coupled to said radio-frequency transceiving unit and generating at least a traffic parameter corresponding to at least a lane in response to said difference-frequency signal,

wherein said antennas are configured to receive a microwave signal having a signal-to-noise ratio reflecting from a target where said signal-to-noise ratio is varied from 0 to 32 dB, and thereby said detecting apparatus is operable in said multi-lane vehicle detection.

2. The detecting apparatus according to claim 1, wherein said antennas are configured at a position to receive said microwave signal at an elevation angle and said detecting apparatus further comprises an adjusting device coupled to said antennas for adjusting one of said position and said elevation angle.

3. The detecting apparatus according to claim 1, wherein said radio-frequency transceiving unit further comprises:

a voltage controlled oscillator;

a buffer amplifier coupled to said voltage controlled oscillator;

a power divider coupled to said buffer amplifier;

a first driving amplifier and a second driving amplifier respectively coupled to said power divider at a first end and a second end thereof;

a mixer coupled to said first driving amplifier; and

a low-noise amplifier coupled to said mixer.

4. The detecting apparatus according to claim 3, wherein said voltage controlled oscillator, said buffer amplifier, said power divider, said first and second driving amplifiers, said mixer and said low-noise amplifier are integrated into a chip.

5. The detecting apparatus according to claim 1, wherein said antennas are spaced from each other at a distance of less than 5 mm.

6. The detecting apparatus according to claim 1, wherein said antennas have an isolation value of at least 40 dB.

7. The detecting apparatus according to claim 1, wherein said traffic parameter is one selected from a group consisting of a vehicle speed, a vehicle classification, an occupancy, a density and a flow.

8. An embedded detecting apparatus for multi-lane vehicle detection, comprising:

a system-on-chip comprising a radio-frequency transceiving module for generating a frequency-modulation continuous-wave signal integrated thereon;

an antenna module coupled to said system-on-chip; and

an intermediate-frequency and digital processing unit coupled to said radio-frequency transceiving module and generating a difference-frequency signal corresponding to at least a traffic parameter of at least a lane in response to said frequency-modulation continuous-wave signal,

wherein said antenna module is configured to receive a microwave signal having a signal-to-noise ratio reflecting from a target where said signal-to-noise ratio is varied from 0 to 32 dB, and thereby said embedded detecting apparatus is operable in said multi-lane vehicle detection.

9. The embedded detecting apparatus according to claim 8, wherein said antenna module comprises at least a pair of antennas of leakage-wave mode.

10. The embedded detecting apparatus according to claim 8, wherein said antennas are configured at a position to receive said microwave signal at an elevation angle and said embedded detecting apparatus further comprises an adjusting device coupled to said antennas for adjusting one of said position and said elevation angle.

11. The embedded detecting apparatus according to claim 9, wherein said antennas are spaced from each other at a distance of less than 5 mm.

12. The embedded detecting apparatus according to claim 9, wherein said antennas have an isolation value of at least 40 dB.

13. The embedded detecting apparatus according to claim 8, wherein said traffic parameter is one selected from a group consisting of a vehicle speed, a vehicle classification, an occupancy, a density and a flow.