Vehicular traffic sensor

• US 20040135703A1
• Filed: 12/23/2003
• Published: 07/15/2004
• Est. Priority Date: 09/27/2001
• Status: Active Grant

• Current Assignee: David V. Arnold, John B. Dougall Jr, Jonathan L. Waite, Logan Harris, Michael Jensen, Ryan Smith, Thomas William Karlinsey
• Original Assignee: David V. Arnold, John B. Dougall Jr, Jonathan L. Waite, Logan Harris, Michael Jensen, Ryan Smith, Thomas William Karlinsey
• Inventors: Jensen, Michael, Waite, Jonathan L., Arnold, David V., Smith, Ryan, Dougall, John B. Jr., Karlinsey, Thomas William, Harris, Logan
• Granted Patent: US 7,427,930 B2
• Time in Patent Office: Days
• US Class Current: 340/933
• CPC Class Codes: G01S 13/04 Systems determining presence of a target based on relative movement of target G01S13/56
• CPC Class Codes: G01S 13/34 using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
• CPC Class Codes: G01S 7/032 Constructional details for solid-state radar subsystems
• CPC Class Codes: G01S 7/352 Receivers
• CPC Class Codes: G08G 1/042 using inductive or magnetic detectors
• CPC Class Codes: H01Q 13/106 Microstrip slot antennas patch antenna elements H01Q9/0407
• CPC Class Codes: H01Q 21/0006 Particular feeding systems
• CPC Class Codes: H01Q 21/08 the units being spaced along or adjacent to a rectilinear path waveguide fed H01Q21/0037

Abstract

A vehicle traffic sensor for detecting and monitoring vehicular targets is presented. The sensor employs a planar design resulting in a reduced profile sensor. The sensor includes a multi-layer radio frequency board with RF components on one of the sides and both isolation and planar array antennas on the opposing side. The antennas are preferably tapered planar array antennas which include one transmit antenna and one receive antenna. The sensor also includes at least one logic or signal processing board populated with components on a first side and a ground plane on a second side positioned toward the RF componentry of the RF board to form an RF shield. The boards are housed within a housing that is permeable, at least on the side through which the antenna structures propagate.

Claims

1. A sensor for monitoring vehicles on a roadway, the sensor comprising:

a transmit portion comprising;

a digital signal generator that digitally generates a modulated signal; and

a transmit antenna for transmitting the modulated signal towards vehicles on a roadway;

a received portion comprising;

a receive antenna for receiving reflections of the modulated signal from vehicles on the roadway, wherein the reflections of the modulated signal are processed to produce traffic data representing the vehicles on the roadway;

wherein the transmit antenna and the receive antenna are the same antenna used at different times to either transmit the modulated signal or to receive the reflections of the modulated signal.

2. A sensor as defined in claim 1, wherein the transmit antenna is a first array of series fed coplanar loop elements and wherein the receive antenna is a second array of series fed coplanar loop elements.

3. A sensor as defined in claim 1, wherein the digital signal generator further comprises at least one of:

a direct digital synthesizer that is coupled with a phase locked loop;

a modulated signal digital generator and an up-converter; and

a direct digital to analog conversion generator that produces the modulate signal.

4. A sensor for monitoring vehicles on a roadway, the sensor comprising:

a transmit portion comprising;

a digital signal generator that digitally generates a modulated signal; and

an antenna for transmitting the modulated signal towards vehicles on a roadway and receiving receiving reflections of the modulated signal from vehicles on the roadway, wherein the reflections of the modulated signal are processed to produce traffic data representing the vehicles on the roadway and wherein said antenna is used at different times to either transmit the modulated signal or to receive the reflections of the modulated signal.