Search

EP-4741870-A1 - RADAR COMPONENT

EP4741870A1EP 4741870 A1EP4741870 A1EP 4741870A1EP-4741870-A1

Abstract

An exemplary embodiment of the invention relates to a radar component (1) comprising an electric circuit board (5) having a patterned electrical layer (10), a chip (15) comprising an electronic-photonic-integrated circuit which is mounted on a top surface (5a) of the circuit board (5) and electrically connected to electrical traces (20) formed by sections of the electrical layer (10), at least one optical fiber (25) being butt-coupled to an assigned optical waveguide (30) integrated in the chip (15), the core of the butt-coupled end of the fiber (25) lying in the same plane (P) as the optical waveguide (30), said plane (P) being parallel to the said top surface (5a) of the circuit board (5), wherein the alignment between the fiber (25) and the optical waveguide (30) provides a straight, linear transmission of optical radiation between the optical fiber (25) and the optical waveguide (30), at least one radar antenna pad (35) formed by a metal pad of the electrical layer (10) or a metal pad of another electrical layer (100) of the circuit board (5), wherein the radar antenna pad (35) is connected to the chip (15) via at least one of said traces (20), and a microwave waveguide formed by a hollow pipe (45) and coupled to said radar antenna pad (35), wherein the fiber (25) is mechanically carried by a groove of the chip (15) which aligns the core of the fiber (25) with the assigned optical waveguide (30), and wherein a longitudinal axis of the hollow pipe (45) is angled to said plane (P), at least in the vicinity of the radar antenna pad (35).

Inventors

  • MEISTER, STEFAN
  • OTTE, SVEN

Assignees

  • Xavveo GmbH

Dates

Publication Date
20260513
Application Date
20241107

Claims (15)

  1. A radar component (1) comprising an electric circuit board (5) having a patterned electrical layer (10), a chip (15) comprising an electronic-photonic-integrated circuit which is mounted on a top surface (5a) of the circuit board (5) and electrically connected to electrical traces (20) formed by sections of the electrical layer (10), at least one optical fiber (25) being butt-coupled to an assigned optical waveguide (30) integrated in the chip (15), the core of the butt-coupled end of the fiber (25) lying in the same plane (P) as the optical waveguide (30), said plane (P) being parallel to the said top surface (5a) of the circuit board (5), wherein the alignment between the fiber (25) and the optical waveguide (30) provides a straight, linear transmission of optical radiation between the optical fiber (25) and the optical waveguide (30), at least one radar antenna pad (35) formed by a metal pad of the electrical layer (10) or a metal pad of another electrical layer (100) of the circuit board (5), wherein the radar antenna pad (35) is connected to the chip (15) via at least one of said traces (20), and a microwave waveguide formed by a hollow pipe (45) and coupled to said radar antenna pad (35), wherein the fiber (25) is mechanically carried by a groove of the chip (15) which aligns the core of the fiber (25) with the assigned optical waveguide (30), and wherein a longitudinal axis of the hollow pipe (45) is angled to said plane (P), at least in the vicinity of the radar antenna pad (35).
  2. Radar component (1) of claim 1 wherein a substrate (40) is mounted on said top surface (5a) of the electric circuit board (5) or on a bottom surface (5b) of the electric circuit board (5), and wherein the hollow pipe (45) is embedded in said substrate (40) and passes through said substrate (40).
  3. Radar component (1) of claim 2 wherein a heat spreader (60) is mounted on top of the chip (15), and wherein the substrate (40) is arranged adjacent to the heat spreader (60), the substrate (40) blocking a movement of the heat spreader (60) relatively to said chip (15) in at least one direction that is parallel to said plane (P).
  4. Radar component (1) of any of the preceding claims, wherein the substrate (40) forms a bracket (44) and/or hole (41) providing an opening into which the heat spreader (60) protrudes in a direction perpendicular to said plane (P), the bracket and/or hole blocking any movement of the heat spreader (60) in at least two directions that are parallel to said plane (P).
  5. Radar component (1) of any of the preceding claims 1-3, wherein the heat spreader (60) forms a bracket and/or hole (61) providing an opening into which the substrate (40) protrudes in a direction perpendicular to said plane (P), the bracket and/or hole blocking any movement of the substrate (40) in at least two directions that are parallel to said plane (P).
  6. Radar component (1) of any of the preceding claims wherein the circuit board (5) has a cutout (51) which the fiber (25) passes towards the assigned optical waveguide (30), wherein a section of the substrate (40) and/or a section of the heat spreader (60) is located above or beneath the cutout (51), and wherein said section of the substrate (40) and/or said section of the heat spreader (60) is connected to or touches the fiber (25) thereby providing support perpendicular to said plane (P) and a vertical stress relief for the fiber (25) .
  7. Radar component (1) of any of the preceding claims wherein the substrate (40) and/or the heat spreader (60) completely cover the top surface (5a) of the circuit board (5) .
  8. Radar component (1) of any of the preceding claims 1-7 wherein the heat spreader (60) completely covers the top surface (5a) of the circuit board (5), and wherein the substrate (40) completely covers the bottom surface (5b) of the circuit board (5).
  9. Radar component (1) of any of the preceding claims wherein the substrate (40) is glued to the circuit board (5) .
  10. Radar component (1) of any of the preceding claims wherein the hollow pipe (45) provides an internal interface (50) coupled to said radar antenna pad (35), and an external interface (55) for emitting radar radiation and/or receiving radar radiation, and wherein the external interface (50) is formed by an end section of the pipe (45) that provides a radar antenna.
  11. Radar component (1) of any of the preceding claims wherein the pipe (45) is bend in an intermediate section arranged between the internal interface (50) and the external interface (55), and wherein the external interface (55) is offset from the internal interface (50) in the direction perpendicular to the plane (P), thereby increasing the distance between the chip (15) and the external interface (55) relative to the distance between the chip (15) and the internal interface (50).
  12. Radar component (1) of any of the preceding claims wherein two or more radar antenna pads (35) are formed by metal pads of the electrical layer (10) or metal pads of another electrical layer (100) of the circuit board (5), wherein each radar antenna pad (35) is connected to the chip (15), wherein two or more microwave waveguides are each formed by a hollow pipe (45) and coupled to a respective radar antenna pad (35), the hollow pipes (45) are embedded in said substrate (40) and pass through said substrate (40), and wherein the substrate (40) comprises at least one attenuation zone (75) between adjacent hollow pipes (45) and/or at least one attenuation zone (75) between one of the hollow pipes (45) and the chip (15).
  13. Radar component (1) of any of the preceding claims wherein the substrate (40) is a moulded part and walls of the hollow pipes (45) are metallized surfaces of through holes in the moulded part.
  14. Radar component (1) of any of the preceding claims wherein the chip (15) comprises silicon photonics components and/or CMOS components.
  15. Vehicle (900) or part (910) of a vehicle comprising a radar component (1) according to of any of the preceding claims.

Description

The invention relates to radar components as well as vehicles and parts of vehicles that comprise radar components. Background of the invention German Patent DE 10 2021 110 820 B3 discloses a radar sensor device with a transmitting and receiving path, an optical input for receiving an optical transmission signal, an optical output for providing an optical output signal, and an antenna for emitting an external electrical signal and receiving an electrical receiving signal. The radar sensor device is designed as a one-chip system. Objective of the present invention An objective of the present invention is to propose a compact radar component that can be easily manufactured. Brief summary of the invention An exemplary embodiment of the present invention relates to a radar component comprising an electric circuit board having a patterned electrical layer, a chip comprising an electronic-photonic-integrated circuit which is mounted on a top surface of the circuit board and electrically connected to electrical traces formed by sections of the electrical layer, at least one optical fiber being butt-coupled to an assigned optical waveguide integrated in the chip, the core of the butt-coupled end of the fiber lying in the same plane as the optical waveguide, said plane being parallel to the said top surface of the circuit board, wherein the alignment between the fiber and the waveguide provides a straight, linear transmission of optical radiation between the optical fiber and the optical waveguide, at least one radar antenna pad formed by a metal pad of the electrical layer or a metal pad of another electrical layer of the circuit board, wherein the radar antenna pad is connected to the chip via at least one of said traces, and a microwave waveguide formed by a hollow pipe and coupled to said radar antenna pad, wherein the fiber is mechanically carried by a groove of the chip which aligns the core of the fiber with the assigned optical waveguide, and wherein a longitudinal axis of the hollow pipe is angled to said plane, at least in the vicinity of the radar antenna pad. An advantage of the above embodiment is that the radar component is very compact since the optical fibers are being butt-coupled via grooves to assigned optical waveguide integrated in the chip and therefore lay in the same plane as the optical waveguides. The microwave waveguide(s) are formed by hollow pipes and are angled with respect to said plane in order to facilitate the manufacturing process. In the vicinity of the radar antenna pad, the longitudinal axis of the hollow pipe is preferably perpendicular to said plane. A substrate may be mounted on said top surface of the electric circuit board or on a bottom surface of the electric circuit board. The hollow pipe is preferably embedded in said substrate and passes through said substrate. A heat spreader may be mounted on top of the chip. The substrate may be arranged adjacent to the heat spreader. Then, the substrate may block a movement of the heat spreader relatively to said chip in at least one direction that is parallel to said plane. The substrate may form a bracket and/or hole providing an opening into which the heat spreader protrudes in a direction perpendicular to said plane. The bracket and/or hole may block any movement of the heat spreader in at least two directions that are parallel to said plane. Alternatively, the heat spreader may form a bracket and/or hole providing an opening into which the substrate protrudes in a direction perpendicular to said plane. Then, the bracket and/or hole may block any movement of the substrate in at least two directions that are parallel to said plane. One of those two directions mentioned above is preferably parallel to the fiber and another of those two directions is preferably perpendicular thereto. The bracket is preferably U-shaped. The circuit board may have a cutout which the fiber passes towards the assigned optical waveguide. The cutout preferably defines the outer peripheral edge of the circuit board. The longitudinal axis of the cutout my be parallel to the longitudinal axis of the fiber. A section of the substrate and/or a section of the heat spreader may be located above or beneath the cutout. The latter section of the substrate and/or the latter section of the heat spreader is preferably connected to (e. g. glued to) the fiber or preferably at least touches the fiber thereby providing support perpendicular to said plane and a vertical stress relief for the fiber. The substrate and/or the heat spreader preferably completely cover the top surface of the circuit board. For instance, the heat spreader may completely cover the top surface of the circuit board, and the substrate may completely cover the bottom surface of the circuit board. The substrate is preferably attached to the circuit board without the need of additional heat in order to avoid additional thermal impact on the fibers and their connection to the optical waveguides during