Compact multi range automotive radar assembly with end-fire antennas on both sides of a printed circuit board

• US 10,401,491 B2
• Filed: 11/15/2016
• Issued: 09/03/2019
• Est. Priority Date: 11/15/2016
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation)
• Inventors: Lee, Jae Seung
• Primary Examiner(s): Magloire, Vladimir
• Assistant Examiner(s): Braswell, Donald H B
• Application Number:
  US15/351,714
• Publication Number:
  US 20180136327A1
• Time in Patent Office: 1,022 Days
• Field of Search: None
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/93271 in the front of the vehicles
• CPC Class Codes: G01S 2013/93272 in the back of the vehicles
• CPC Class Codes: G01S 2013/93274 on the side of the vehicles
• CPC Class Codes: G01S 7/032 Constructional details for solid-state radar subsystems
• CPC Class Codes: G01S 7/038 Feedthrough nulling circuits
• CPC Class Codes: H01Q 1/3233 particular used as part of a sensor or in a security system, e.g. for automotive radar, navigation systems

Abstract

A vehicular radar board includes a PCB having a first surface and a second surface. The first surface of the board includes a plurality of transmitter end-fire antennas and a first plurality of receiver end-fire antennas that are spaced apart by a first gap. The second surface of the board includes a second plurality of receiver end-fire antennas that are spaced apart by a second gap that is greater than the first gap. The board also includes a first RFIC positioned on the first surface and designed to control the plurality of transmitter antennas to transmit radar signals and to receive a first reflected signal of the radar signals from the first plurality of receiver antennas. The board also includes a second RFIC positioned on the second surface and designed to receive a second reflected signal of the radar signals from the second plurality of receiver antennas.

Claims

1. A vehicular radar board comprising:

a printed circuit board (PCB) having a first planar surface and a second planar surface opposite the first planar surface;

a plurality of transmitter end-fire antennas positioned on the first planar surface of the PCB;

a first plurality of receiver end-fire antennas positioned on the first planar surface of the PCB and each being spaced apart by a first gap;

a second plurality of receiver end-fire antennas positioned on the second planar surface of the PCB and each being spaced apart by a second gap that is greater than the first gap, the plurality of transmitter end-fire antennas, the first plurality of receiver end-fire antennas, and the second plurality of receiver end-fire antennas each having a transmission end that is oriented in a single direction;

a first radio frequency integrated circuit (RFIC) positioned on the first planar surface of the PCB, coupled to the plurality of transmitter end-fire antennas and the first plurality of receiver end-fire antennas, and configured to control the plurality of transmitter end-fire antennas to transmit radar signals, to receive a first reflected signal of the radar signals from the first plurality of receiver end-fire antennas, and to determine whether an object is present within a first angle about the single direction based on the first reflected signal received from the first plurality of receiver end-fire antennas; and

a second RFIC positioned on the second planar surface of the PCB, coupled to the second plurality of receiver end-fire antennas, and configured to receive a second reflected signal of the radar signals from the second plurality of receiver end-fire antennas and to determine whether the object is present within a second angle about the single direction based on the second reflected signal received from the second plurality of receiver end-fire antennas, the second angle being less than the first angle.

2. The vehicular radar board of claim 1 wherein the first RFIC is further configured to determine whether an object is present within a first distance of the vehicular radar board based on the first reflected signal received from the first plurality of receiver end-fire antennas, and the second RFIC is further configured to determine whether the object is present within a second distance of the vehicular radar board based on the second reflected signal received from the second plurality of receiver end-fire antennas, the second distance being greater than the first distance.

3. The vehicular radar board of claim 1 wherein each antenna of the plurality of transmitter end-fire antennas, the first plurality of receiver end-fire antennas, and the second plurality of receiver end-fire antennas has a chip connection end and includes:

a chip connection lead positioned adjacent to the chip connection end of each antenna and electrically coupled to a corresponding RFIC;

a balun positioned adjacent to the chip connection lead of each antenna and configured to convert an unbalanced signal to a balanced signal or to convert a balanced signal to an unbalanced signal;

a wave section having a first wave section and a second wave section separated by a space and configured to transmit a wireless radar signal; and

a tapered section positioned between the balun and the wave section of each antenna and tapered towards the balun from the wave section.

4. The vehicular radar board of claim 1 wherein the second plurality of receiver end-fire antennas includes a greater quantity of end-fire antennas than the first plurality of receiver end-fire antennas such that the second plurality of receiver end-fire antennas has a greater resolution than the first plurality of receiver end-fire antennas.

5. The vehicular radar board of claim 1 wherein the radar signals transmitted by the plurality of transmitter end-fire antennas have a wavelength and wherein a thickness of the PCB from the first planar surface to the second planar surface is greater than or equal to an amount that is half of the wavelength.

6. The vehicular radar board of claim 1 further comprising a second plurality of transmitter end-fire antennas positioned on the second planar surface of the PCB and wherein the second RFIC is also coupled to the second plurality of transmitter end-fire antennas and further configured to control the second plurality of transmitter end-fire antennas to transmit second radar signals and to also receive a reflected signal of the second radar signals from the second plurality of receiver end-fire antennas.

7. A vehicular radar system comprising:

a first radar board having;

a first printed circuit board (PCB),

a plurality of transmitter end-fire antennas positioned on the first PCB,

a first plurality of receiver end-fire antennas positioned on the first PCB and each being spaced apart by a first gap, and

a first radio frequency integrated circuit (RFIC) positioned on the first PCB, coupled to the plurality of transmitter end-fire antennas and the first plurality of receiver end-fire antennas, and configured to control the plurality of transmitter end-fire antennas to transmit radar signals, to receive a first reflected signal of the radar signals from the first plurality of receiver end-fire antennas, and to determine whether an object is present in an environment of the vehicular radar system based on the received first reflected signal and to determine whether the object is present within a first distance of the vehicular radar system based on the first reflected signal received from the first plurality of receiver end-fire antennas;

a second radar board stacked above or below the first radar board and having;

a second PCB,

a second plurality of receiver end-fire antennas positioned on the first PCB and each being spaced apart by a second gap that is greater than the first gap, and

a second RFIC positioned on the second PCB, coupled to the second plurality of receiver end-fire antennas, and configured to receive a second reflected signal of the radar signals from the second plurality of receiver end-fire antennas and to determine whether the object is present in the environment of the vehicular radar system based on the received second reflected signal and to determine whether the object is present within a second distance of the vehicular radar system based on the second reflected signal received from the second plurality of receiver end-fire antennas; and

a third radar board stacked above or below at least one of the first radar board or the second radar board and having;

a third PCB,

a third plurality of receiver end-fire antennas positioned on the third PCB and each being spaced apart by a third gap that is greater than the first gap and less than the second gap, and

a third RFIC positioned on the third PCB, coupled to the third plurality of receiver end-fire antennas, and configured to receive a third reflected signal of the radar signals from the third plurality of receiver end-fire antennas and to determine whether the object is present within a third distance of the vehicular radar system based on the received third reflected signal, the third distance being greater than the first distance and less than the second distance.

8. The vehicular radar system of claim 7 wherein:

the plurality of transmitter end-fire antennas, the first plurality of receiver end-fire antennas, and the second plurality of receiver end-fire antennas each have a transmission end that is oriented in a single direction;

the first RFIC is further configured to determine whether the object is present within a first angle about the single direction based on the first reflected signal received from the first plurality of receiver end-fire antennas; and

the second RFIC is further configured to determine whether the object is present within a second angle about the single direction based on the second reflected signal received from the second plurality of receiver end-fire antennas, the second angle being less than the first angle.

9. The vehicular radar system of claim 7 wherein each antenna of the plurality of transmitter end-fire antennas, the first plurality of receiver end-fire antennas, and the second plurality of receiver end-fire antennas has a chip connection end and a transmission end and includes:

a chip connection lead positioned adjacent to the chip connection end of each antenna and electrically coupled to a corresponding RFIC;

a balun positioned adjacent to the chip connection lead of each antenna and configured to convert an unbalanced signal to a balanced signal or to convert a balanced signal to an unbalanced signal;

a wave section having a first wave section and a second wave section separated by a space and configured to transmit a wireless radar signal; and

a tapered section positioned between the balun and the wave section of each antenna and tapered towards the balun from the wave section.

10. The vehicular radar system of claim 7 wherein the second plurality of receiver end-fire antennas includes a greater quantity of end-fire antennas than the first plurality of receiver end-fire antennas such that the second plurality of receiver end-fire antennas has a greater resolution than the first plurality of receiver end-fire antennas.

11. The vehicular radar system of claim 7 wherein the radar signals transmitted by the plurality of transmitter end-fire antennas have a wavelength and wherein the first PCB and the second PCB are separated by an amount that is at least half of the wavelength.

12. The vehicular radar system of claim 7 wherein the second radar board further includes a second plurality of transmitter end-fire antennas positioned on the second PCB and wherein the second RFIC is also coupled to the second plurality of transmitter end-fire antennas and further configured to control the second plurality of transmitter end-fire antennas to transmit second radar signals and to also receive a reflected signal of the second radar signals from the second plurality of receiver end-fire antennas.

13. The vehicular radar system of claim 7 further comprising:

a fourth radar board stacked above or below at least one of the first radar board, the second radar board, or the third radar board and having;

a fourth PCB,

a fourth plurality of receiver end-fire antennas positioned on the fourth PCB and each being spaced apart by a fourth gap that is equal to the second gap, and

a fourth RFIC positioned on the fourth PCB, coupled to the fourth plurality of receiver end-fire antennas, and configured to receive a fourth reflected signal of the radar signals from the fourth plurality of receiver end-fire antennas and to determine data regarding the object based on the fourth reflected signal; and

an electronic control unit (ECU) coupled to the first RFIC, the second RFIC, the third RFIC, and the fourth RFIC and configured to receive data regarding the object from at least two of the first RFIC, the second RFIC, the third RFIC, or the fourth RFIC and to determine three dimensional information regarding the object based on the received data.

14. A vehicular radar system comprising:

a first vehicular radar board having;

a printed circuit board (PCB) having a first planar surface, a second planar surface opposite the first planar surface, and a thickness from the first planar surface to the second planar surface,

a plurality of transmitter end-fire antennas positioned on the first planar surface of the PCB,

a first plurality of receiver end-fire antennas positioned on the first planar surface of the PCB and each being spaced apart by a first gap,

a second plurality of receiver end-fire antennas positioned on the second planar surface of the PCB and each being spaced apart by a second gap that is greater than the first gap,

a first radio frequency integrated circuit (RFIC) positioned on the first planar surface of the PCB, coupled to the plurality of transmitter end-fire antennas and the first plurality of receiver end-fire antennas, and configured to control the plurality of transmitter end-fire antennas to transmit radar signals having a wavelength and to receive a first reflected signal of the radar signals from the first plurality of receiver end-fire antennas that corresponds to an object such that the thickness of the PCB from the first planar surface to the second planar surface is greater than or equal to an amount that is half of the wavelength, and

a second RFIC positioned on the second planar surface of the PCB, coupled to the second plurality of receiver end-fire antennas, and configured to receive a second reflected signal of the radar signals from the second plurality of receiver end-fire antennas that corresponds to the object;

a second vehicular radar board stacked above or below the first vehicular radar board and having similar features as the first vehicular radar board and being spaced from the first vehicular radar board by a distance that is greater than or equal to the amount that is at half of the wavelength; and

an electronic control unit (ECU) coupled to the first vehicular radar board and the second vehicular radar board and configured to receive data regarding the object from the first vehicular radar board and the second vehicular radar board and to determine three dimensional information regarding the object based on the data received from the first vehicular radar board and the second vehicular radar board.

15. The vehicular radar system of claim 14 wherein:

the plurality of transmitter end-fire antennas, the first plurality of receiver end-fire antennas, and the second plurality of receiver end-fire antennas each have a transmission end that is oriented in a single direction;

the first RFIC is further configured to determine whether the object is present within a first distance of the first vehicular radar board and a first angle about the single direction of the first vehicular radar board based on the first reflected signal received from the first plurality of receiver end-fire antennas;

the second RFIC is further configured to determine whether the object is present within a second distance of the first vehicular radar board and a second angle about the single direction of the first vehicular radar board based on the second reflected signal received from the second plurality of receiver end-fire antennas;

the second distance is greater than the first distance; and

the second angle is less than the first angle.

16. The vehicular radar system of claim 14 wherein the second plurality of receiver end-fire antennas includes a greater quantity of end-fire antennas than the first plurality of receiver end-fire antennas such that the second plurality of receiver end-fire antennas has a greater resolution than the first plurality of receiver end-fire antennas.