Radar device and radar detection method
Embodiments disclosed herein relates to a radar device, and more particularly, to a radar device having a structure that reduces the influence of an internal reflected wave, which is capable of preventing a target sensing performance from being deteriorated by a reflected wave reflected within the radar device, while having a cover structure that is capable of protecting an antenna from the outside.
1. A radar device comprising:
at least one transmission antenna configured to output a transmission polarization signal having a predetermined transmission polarization angle;
at least one reception antenna configured to receive a reception polarization signal having a predetermined reception polarization angle; and
a lower housing and an upper cover configured to accommodate the at least one transmission antenna and the at least one reception antenna,
wherein, between the at least one transmission antenna and the upper cover, a transmission-side ferromagnetic material exists and a first transmission-side strip conductor positioned above the transmission-side ferromagnetic material and/or a second transmission-side strip conductor positioned below the transmission-side ferromagnetic material further exist, and
wherein, between the at least one reception antenna and the upper cover, a reception-side ferromagnetic material exists and a first reception-side strip conductor positioned above the reception-side ferromagnetic material a second reception-side strip conductor positioned below the reception-side ferromagnetic material further exist.
2. The radar device of claim 1 , wherein, between the transmission antenna and the upper cover, a first transmission-side dielectric, the first transmission-side strip conductor, the transmission-side ferromagnetic material, the second transmission-side strip conductor, and a second transmission-side dielectric are stacked in that order, and
wherein, between the reception antenna and the upper cover, a first reception-side dielectric, the first reception-side strip conductor, the reception-side ferromagnetic material, the second reception-side strip conductor, and a second reception-side dielectric are stacked in that order.
3. The radar device of claim 2 , wherein the first transmission-side dielectric and the first reception-side dielectric are integrated and stacked on a same layer,
the transmission-side ferromagnetic material and the reception-side ferromagnetic material are integrated and stacked on a same layer,
the second transmission-side strip conductor and the second reception-side strip conductor are integrated and stacked on a same layer, and
the second transmission-side dielectric and the second reception-side dielectric are integrated and stacked on a same layer.
4. The radar device of claim 1 , wherein the transmission polarization angle of the transmission antenna and the reception polarization angle of the reception antenna are different from each other by 90 degrees.
5. The radar device of claim 1 , wherein the transmission-side ferromagnetic material and the reception-side ferromagnetic material have a thickness of λ/4.
6. The radar device of claim 1 , wherein the first transmission-side strip conductor has a polarization characteristic of a predetermined first polarization angle and allows only a signal that has a polarization angle that is different from the first polarization angle by 90 degrees to pass therethrough,
the transmission-side ferromagnetic material outputs a signal input thereto in a state in which a polarization angle of the input signal is changed by +45 degrees,
the second transmission-side strip conductor has a polarization characteristic of a predetermined second polarization angle and allows only a signal that has a polarization angle that is different from the second polarization angle by 90 degrees to pass therethrough,
the second reception-side strip conductor has a polarization characteristic of a predetermined fourth polarization angle and allows only a signal that has a polarization angle that is different from the fourth polarization angle by 90 degrees to pass therethrough,
the reception-side ferromagnetic material outputs a signal input thereto in a state in which a polarization angle of the input signal is changed by +45 degrees, and
the first reception-side strip conductor has a polarization characteristic of a predetermined third polarization angle and allows only a signal that has a polarization angle that is different from the third polarization angle by 90 degrees to pass therethrough.
7. The radar device of claim 6 , wherein the transmission polarization angle of the transmission antenna and the first polarization angle of the first transmission-side strip conductor are different from each other by 90 degrees,
the reception polarization angle of the reception antenna and the third polarization angle of the first reception-side strip conductor are different from each other by 90 degrees,
the first polarization angle of the first transmission-side strip conductor and the third polarization angle of the first reception-side strip conductor are different from each other by 90 degrees,
the second polarization angle of the second transmission-side strip conductor and the fourth polarization angle of the second reception-side strip conductor are equal to each other,
the first polarization angle of the first transmission-side strip conductor and the second polarization angle of the second reception-side strip conductor are different from each other by 45 degrees, and
the third polarization angle of the first reception-side strip conductor and the second polarization angle of the second reception-side strip conductor are different from each other by 45 degrees.
8. The radar device of claim 6 , wherein the transmission polarization angle of the transmission antenna is +45 degrees,
the reception polarization angle of the reception antenna is −45 degrees,
the first polarization angle of the first transmission-side strip conductor is −45 degrees,
the third polarization angle of the first reception-side strip conductor is +45 degrees, and
the second polarization angle of the second transmission-side strip conductor and the fourth polarization angle of the second reception-side strip conductor are horizontal angles.
9. The radar device of claim 6 , wherein the transmission polarization angle of the transmission antenna is −45 degrees,
the reception polarization angle of the reception antenna is +45 degrees,
the first polarization angle of the first transmission-side strip conductor is +45 degrees,
the third polarization angle of the first reception-side strip conductor is −45 degrees, and
the second polarization angle of the second transmission-side strip conductor and the fourth polarization angle of the second reception-side strip conductor are vertical angles.
10. The radar device of claim 6 , wherein the transmission polarization angle of the transmission antenna is a vertical angle,
the reception polarization angle of the reception antenna is a horizontal angle,
the first polarization angle of the first transmission-side strip conductor is a horizontal angle,
the third polarization angle of the first reception-side strip conductor is a vertical angle, and
the second polarization angle of the second transmission-side strip conductor and the fourth polarization angle of the second reception-side strip conductor are +45 degrees.
11. The radar device of claim 6 , wherein the transmission polarization angle of the transmission antenna is a horizontal angle,
the reception polarization angle of the reception antenna is a vertical angle,
the first polarization angle of the first transmission-side strip conductor is a vertical angle,
the third polarization angle of the first reception-side strip conductor is a horizontal angle, and
the second polarization angle of each of the second transmission-side strip conductor and the second reception-side strip conductor is −45 degrees.
12. The radar device of claim 1 , wherein a signal directed from the upper cover toward the transmission antenna is not transmitted to the transmission antenna,
a signal directed from the upper cover toward the reception antenna is not transmitted to the reception antenna, and
a signal reflected from the transmission antenna or the reception antenna and directed toward the upper cover is not transmitted through the upper cover.
13. A radar detection method comprising:
transmitting a transmission polarization signal having a predetermined transmission polarization angle so that at least one transmission antenna detects an object; and
radiating the transmission polarization signal to an outside via a transmission-side strip conductor and a transmission-side ferromagnetic material and through an upper cover,
wherein a polarization angle of the signal radiated to the outside through the upper cover is different from a transmission polarization angle of the transmission polarization signal transmitted from the transmission antenna.
14. The radar detection method of claim 13 , further comprising:
causing an external signal to enter an inside through the upper cover; and
receiving, by the at least one reception antenna, the signal that enters the inside through the upper cover,
wherein the polarization angle of the signal that enters the inside through the upper cover is different from the reception polarization angle of the reception polarization signal, which is a signal that reaches the at least one reception antenna.
15. The radar detection method of claim 14 , wherein the transmission polarization angle of the transmission antenna and the reception polarization angle of the reception antenna are different from each other by 90 degrees.