Radar for vehicle
Disclosed is a radar for a vehicle configured to detect objects around a vehicle using an antenna, and the radar includes a substrate-integrated waveguide (SIW) in which a plurality of bent slots is formed, at least one processor electrically connected to the substrate-integrated waveguide, and a differential line electrically connecting the substrate-integrated waveguide to the at least one processor.
1. A radar for a vehicle configured to detect an object around a vehicle using an antenna, the radar comprising:
a slot antenna comprising a substrate-integrated waveguide (SIW) in which a plurality of bent slots are provided;
at least one processor electrically connected to the slot antenna; and
a differential line electrically connecting the slot antenna to the at least one processor,
wherein the differential line comprises:
a first line extending from a portion of the SIW in a width direction of the SIW, and
a second line spaced apart from the first line and extending from a portion of the SIW in the width direction,
wherein a center line of the first line is located at a point spaced apart from a short-circuited surface of the SIW by a fourth of a guide wavelength in a longitudinal direction of the SIW.
2. The radar of claim 1 , wherein a center line of the second line is formed at a point spaced apart from the center line of the first line by half the guide wavelength in the longitudinal direction.
3. The radar of claim 2 , wherein the SIW comprises:
a first metal plate;
a second metal plate configured to be in electrical communication with the first metal plate via a plurality of via holes; and
a dielectric located between the first metal plate and the second metal plate.
4. The radar of claim 3 , wherein the plurality of bent slots are provided in the first metal plate.
5. The radar of claim 3 , wherein the via holes are removed around a portion of the SIW in which the differential line is formed.
6. The radar of claim 1 , wherein the second line is formed symmetrically to the first line with respect to an imaginary line formed between the first line and the second line.
7. The radar of claim 6 , wherein the first line comprises:
a first sub line extending from the SIW in the width direction;
a second sub line extending from the first sub line toward the second line while forming an acute angle or an obtuse angle with the first sub line; and
a third sub line extending from the second sub line in the width direction.
8. The radar of claim 7 , wherein a connection portion between the first sub line and the second sub line is formed so as to be rounded, and
wherein a connection portion between the second sub line and the third sub line is formed so as to be rounded.
9. The radar of claim 6 , wherein the second line comprises:
a first sub line extending from the SIW in the width direction;
a second sub line extending from the first sub line toward the first line while forming an acute angle or an obtuse angle with the first sub line; and
a third sub line extending from the second sub line in the width direction.
10. The radar of claim 1 , wherein the SIW comprises a slot provided between the first line and the second line.
11. The radar of claim 1 , wherein the SIW comprises:
a first slot extending in a longitudinal direction of the SIW;
a second slot extending from an end of the first slot in a direction different from the longitudinal direction; and
a third slot extending from an end of the second slot in the longitudinal direction.
12. The radar of claim 11 , wherein an imaginary center line in a horizontal direction of the first slot is spaced apart from an imaginary center line of the SIW, which extends in the longitudinal direction, in a first direction.
13. The radar of claim 12 , wherein a center line in a horizontal direction of the third slot is spaced apart from the imaginary center line in a direction opposite the first direction.
14. The radar of claim 13 , wherein at least a portion of the second slot intersects the imaginary center line.
15. The radar of claim 1 , wherein each of the plurality of bent slots has a length corresponding to a half wavelength of a resonant frequency for transmitting and receiving electromagnetic waves.
16. A radar for a vehicle configured to detect an object around a vehicle using an antenna, the radar comprising:
a slot antenna comprising a substrate-integrated waveguide (SIW) in which a plurality of bent slots are provided;
at least one processor electrically connected to the slot antenna; and
a differential line electrically connecting the slot antenna to the at least one processor,
wherein the SIW comprises:
a first bent slot provided such that a center thereof is located at a point spaced apart from a short-circuited surface by half a guide wavelength in a longitudinal direction of the SIW, and
a second bent slot provided such that a center thereof is located at a point spaced apart from the center of the first bent slot by the guide wavelength in the longitudinal direction.
17. A radar for a vehicle configured to detect an object around a vehicle using an antenna, the radar comprising:
a slot antenna comprising a substrate-integrated waveguide (SIW) in which a plurality of bent slots are provided;
at least one processor electrically connected to the slot antenna; and
a differential line electrically connecting the slot antenna to the at least one processor,
wherein the plurality of bent slots makes a surface current of the substrate-integrated waveguide discontinuous.