Object detection sensor with radome cover configuration to reduce transmitter-receiver couplings

1. A sensor device, comprising

a transmitter;

a receiver having at least one lobe and at least one null; and

a cover near the transmitter and the receiver, the cover including a surface facing toward the transmitter and the receiver, the surface being at an angle relative to the receiver to direct at least some radiation transmitted by the transmitter and reflected from the surface toward the at least one null,

wherein

the receiver has a field of view,

the at least one lobe includes a main lobe near a center of the field of view,

the at least one null includes a first null on one side of the main lobe and a second null on another side of the main lobe,

there is an angular separation between the first null and the second null,

the angle of the surface has a preselected relationship to the angular separation, and

a sum of the angle of the surface plus one-quarter the angular separation equals 90°.

2. The sensor device of claim 1 , wherein the angle of the surface directs a majority of the radiation reflected from the surface toward the at least one null.

3. The sensor device of claim 2 , wherein the angle of the surface directs all of the radiation reflected from the surface toward the at least one null.

4. The sensor device of claim 1 , comprising a base and wherein

the transmitter is supported on the base;

the receiver is supported on the base; and

the angle of the surface is an oblique angle relative to the base.

5. The sensor device of claim 1 , wherein

the receiver comprises an antenna; and

the radiation comprises a radio detection and ranging (RADAR) signal.

6. An automobile vehicle comprising the sensor of claim 1 .

7. The sensor device of claim 1 , wherein

the receiver means has a field of view;

the at least one lobe includes a main lobe near a center of the field of view;

the at least one null includes a first null on side of the main lobe and a second null on another side of the main lobe;

there is an angular separation between the first null and the second null; and

the angle of the surface has a preselected relationship to the angular separation.

8. A sensor device, comprising

a transmitter;

a receiver having at least one lobe and at least one null; and

a cover near the transmitter and the receiver, the cover including a surface facing toward the transmitter and the receiver, the surface being at an angle relative to the receiver to direct at least some radiation transmitted by the transmitter and reflected from the surface toward the at least one null,

wherein

the surface comprises a plurality of surfaces;

the angle comprises a plurality of angles; and

the surfaces are at respective ones of the angles.

9. The sensor device of claim 8 , wherein

a first one of the angles is a positive angle of a selected magnitude;

the angle of a first one of the surfaces is the first one of the angles;

a second one of the angles is a negative angle of the selected magnitude; and

the angle of a second one of the surfaces is the second one of the angles.

10. The sensor device of claim 8 , wherein

the receiver comprises an antenna;

the antenna has a receiver pattern including an angular separation between nulls that are respectively on opposite sides of a main lobe;

the at least one lobe of the receiver corresponds to the main lobe;

the at least one null of the receiver comprises nulls on opposite sides of the at least one lobe of the receiver;

the nulls on opposite sides of the at least one lobe of the receiver are separated by the angular separation; and

the angle of at least one of the surfaces is based on the angular separation.

11. A method of controlling transmission and reception coupling in a sensor device that includes a transmitter, a receiver and a cover near the transmitter and the receiver, wherein the receiver has at least one lobe and at least one null, the method comprising:

transmitting radiation from the transmitter; and

directing at least some of the radiation that reflects off a surface of the cover toward the at least one null based on an angle of the surface relative to the receiver

wherein

the receiver has a field of view;

the at least one lobe includes a main lobe near a center of the field of view;

the at least one null includes a first null on side of the main lobe and a second null on another side of the main lobe;

there is an angular separation between the first null and the second null;

the angle of the surface has a preselected relationship to the angular separation; and

a sum of the angle of the surface plus one-quarter the angular separation equals 90°.

12. The method of claim 11 , wherein the angle of the surface directs a majority of the radiation reflected from the surface toward the at least one null.

13. The method of claim 12 , wherein the angle of the surface directs all of the radiation reflected from the surface toward the at least one null.

14. The method of claim 11 , wherein

the receiver comprises an antenna; and

the radiation comprises a radio detection and ranging (RADAR) signal.

15. A sensor device, comprising

transmitter means for transmitting radiation;

receiver means for receiving radiation, the receiver means having at least one lobe and at least one null; and

cover means for covering the transmitter and the receiver, the cover means including a plurality of surfaces facing toward the transmitter and the receiver, each of the surfaces being at a respective one of a plurality of angles relative to the receiver to direct at least some radiation transmitted by the transmitter and reflected from the surface toward the at least one null.