Dual-band antenna array and RF front-end for mm-wave imager and radar
View Patent ↗The radar includes a PCB having a top surface and a bottom surface, and a processor mounted on the bottom surface of the PCB. The radar includes a second liquid crystal polymer layer formed on the top surface of the printed circuit board, a second microstrip array printed on the second liquid crystal polymer layer, the second microstrip array having a patch, a first liquid crystal polymer layer formed on the second liquid crystal polymer layer, a first microstrip array printed on the first liquid crystal polymer layer, the first microstrip array having a perforated patch, an antenna positioned underneath the patch and connected to the second microstrip array, and a transmit/receive module connected to a bottom surface of the second liquid crystal polymer layer and configured to transmit a first frequency signal to the first microstrip array and a second frequency signal to the second microstrip array.
1. A dual-band radar, comprising:
a first planar antenna configured to transmit or receive at a first frequency, the first planar antenna having a plurality of first patches, each of the plurality of first patches defining a plurality of perforations;
a second planar antenna configured to transmit or receive at a second frequency, the second planar antenna spatially overlapping with the first planar antenna and having a plurality of second patches, each of the plurality of second patches aligning with one of the plurality of perforations of the first planar antenna; and
a transceiver coupled to the first planar antenna and the second planar antenna, the transceiver is configured to generate or receive signals having the first frequency or the second frequency.
2. The dual-band radar of claim 1 , further comprising:
a first layer having a first surface and a second surface opposing the first surface, the first surface contacting the first planar antenna and defining a plurality of openings, each of the plurality of openings aligning with one of the plurality of perforations of the first planar antenna.
3. The dual-band radar of claim 2 , wherein each of the plurality of openings has a first size along the first surface of the first layer and a second size along the second surface of the first layer, and the first size is greater than the second size.
4. The dual-band radar of claim 2 , further comprising:
a second layer having a first surface and a second surface opposing the first surface, the first surface contacting the second planar antenna and a portion of the second surface of the first layer.
5. The dual-band radar of claim 4 , wherein the first layer and the second layer are each made of a material selected from a group consisting of a liquid crystal polymer, a polytetrafluoroethylene (PTFE) ceramic, a PTFE glass fiber material, a Parylene N dielectric material, a low temperature cofired ceramic, a silicon material, a gallium arsenite material, an alumina material, and combinations thereof.
6. The dual-band radar of claim 4 , further comprising:
a ground plane contacting the second surface of the second layer, and configured to connect the transceiver to a ground source.
7. The dual-band radar of claim 6 , further comprising:
a package layer contacting the ground plane, the package layer defining a cavity for housing the transceiver.
8. The dual-band radar of claim 4 , further comprising:
a printed circuit board spatially overlapping with the second layer, the circuit board having a signal processing device in communication with the transceiver.
9. The dual-band radar of claim 4 , further comprising:
a heat rejection area formed on the first surface of the first layer; and
a plurality of thermal vias penetrating the first layer and the second layer, and configured to conduct heat energy from the transceiver to the heat rejection area.
10. The dual-band radar of claim 1 , wherein the second frequency is approximately three times of the first frequency.
11. The dual-band radar of claim 1 , wherein:
each of the plurality of first patches has a first surface area,
each of the plurality of second patches has a second surface area, and
the first surface area is approximately four times of the second surface area.
12. The dual-band radar of claim 1 , further comprising:
a lens positioned to focus a plurality of millimeter waves at a focal plane aligning with the plurality of second patches of the second planar antenna.
13. A radar for use in a motor vehicle, comprising:
a first substrate layer defining a plurality of perforations;
a first patch array printed on the first substrate layer, and configured to transmit or receive at a first frequency, the first patch array having a plurality of first patches, each of the plurality of first patches defining a plurality of openings, each of the plurality of openings aligning with one of the plurality of perforations of the first substrate layer;
a second substrate layer contacting the first substrate layer and opposing the first patch array;
a second patch array printed on the second substrate layer and partially blocking the plurality of perforations of the first substrate layer, the second patch array configured to transmit or receive at a second frequency, and having a plurality of second patches, each aligning with one of the plurality of openings of the first patch array; and
a transceiver positioned adjacent to the second substrate layer and opposing the first substrate layer, the transceiver coupled to the first patch array and the second patch array, and configured to generate or receive signals having the first frequency or the second frequency.
14. The radar of claim 13 , wherein the second frequency is approximately three times of the first frequency.
15. The radar of claim 13 , wherein:
each of the plurality of first patches has a first surface area,
each of the plurality of second patches has a second surface area, and
the first surface area is approximately four times of the second surface area.
16. The radar of claim 13 , further comprising:
a lens arranged to redirect a plurality of millimeter waves to a focal plane overlapping with the plurality of second patches of the second patch array.
17. The radar of claim 13 , further comprising:
a heat rejection area formed on the first substrate layer and opposing the second substrate layer; and
a plurality of thermal vias positioned within the first substrate layer and the second substrate layer, and configured to conduct heat energy from the transceiver to the heat rejection area.
18. A dual-band radar, comprising:
a first patch array positioned along a first plane, and configured to transmit or receive at a first frequency, the first patch array having a plurality of first patches, each of the plurality of first patches defining a plurality of perforations;
a second patch array positioned along a second plane, and having a plurality of second patches, each aligning with one of the plurality of perforations of the first patch array;
a ground plate positioned along a third plane, and defining a plurality of apertures, each of the plurality of apertures cooperating with one of the plurality of second patches to transmit or receive at a second frequency; and
a transceiver in communication with the first patch array and the second patch array, and configured to generate or receive signals having the first frequency or the second frequency.
19. The dual-band radar of claim 18 , further comprising:
a lens arranged to redirect a plurality of millimeter waves to a focal plane overlapping with the plurality of second patches of the second patch array.
20. The dual-band radar of claim 18 , further comprising:
a first substrate layer formed between the first plane and the second plane; and
a second substrate layer formed between the second plane and the third plane,
wherein the first plane is parallel to the second plane, and
wherein the second plane is parallel to the third plane.