Patent Description:
Radar systems use electromagnetic signals to detect and track objects. For example, manufacturers can fabricate radar systems using plastic-molded technology with metallic coatings. Manufacturers generally construct such radar systems with several metal-coated plastic layers bonded together. The bonding process can involve an expensive manufacturing technique performed at a relatively high temperature. Plastic materials that can withstand these high temperatures may be too expensive to be used in some radar applications (e.g., automotive radar systems).

<CIT> describes a vehicular radar sensing system including a radar sensor disposed at a vehicle so as to sense exterior of the vehicle and having at least one transmitter that transmits radio signals and at least one receiver that receive radio signals.

<CIT> describes apparatus and methods of providing an electrical interconnection between an RF circuit and an antenna, the electrical interconnection including a transition via though an antenna substrate.

<CIT> describes a semiconductor device and manufacture thereof.

<CIT> describes a flexible circular corrugated single-mode waveguide.

<CIT> describes an example method of fabricating a waveguide antenna involving providing a first metal layer with waveguide channels formed therein.

This document describes techniques and systems for formed waveguide antennas of a radar assembly. The radar assembly includes a radar system including a printed circuit board (PCB) and a single metal sheet attached to the PCB. The single metal sheet is formed to provide multiple waveguide antennas that each include multiple waveguide channels. Multiple radiation slots are formed on a surface of each of the multiple waveguide channels. The PCB includes a monolithic microwave integrated circuit (MMIC) and a thermally conductive material covering a portion of a first and a second surface of the PCB. The metal sheet is also formed to provide a shield for the MMIC.

This document also describes methods performed by the above-summarized system and other methods set forth herein, as well as means for performing these methods and different configurations of this system.

This Summary introduces simplified concepts for formed waveguide antennas of a radar assembly, which are further described below in the Detailed Description and Drawings. This Summary is not intended to identify essential features of the claimed subject matter, nor is it intended for use in determining the scope of the claimed subject matter. The present disclosure provides a radar assembly according to claim <NUM> and a method according to claim <NUM>. The following discussion is provided for understanding the claims, but the scope of protection is only defined by the claims.

The details of one or more aspects of a formed waveguide antenna for a radar assembly are described in this document with reference to the following figures. The same numbers are often used throughout the drawings to reference like features and components:.

Radar systems are an important sensing technology that some vehicle-based systems rely on to acquire information about the surrounding environment. The antennas for some radar systems are manufactured with materials and manufacturing processes that are relatively expensive and/or introduce performance issues.

Some radar systems use microstrip antennas (e.g., printed antennas, patch antennas) that use photolithographic techniques on a printed circuit board (PCB). Microstrip antennas are relatively inexpensive to manufacture and have a thin planar profile that can be easily integrated into many applications. Microstrip antennas, however, may not provide sufficient performance characteristics for many applications of radar, including automotive radar applications.

To improve the performance characteristics for automotive applications, some manufacturers use injection-molded antennas. Injection-molded antennas can include plastic layers, including a polyetherimide (PEI) layer, with a metal coating (e.g., a silver coating that is applied via physical vapor deposition (PVD)). These plastic layers can be bonded together using solder (e.g., tin-bismuth (Sn-Bi) solder) or other similar techniques. The bonding process, however, is performed at relatively high temperatures (e.g., approximately <NUM>). Plastics that can sustain these higher temperatures are generally more expensive than other materials that cannot tolerate heat as well as the high-temperature plastics.

In contrast, this document describes techniques and systems to minimize cost and improve performance characteristics for antenna waveguides. A radar system is disclosed with the features of claim <NUM>.

In this way, the described techniques and systems permit the waveguide antennas to be formed with materials and a manufacturing process that reduces costs while still providing high performance (e.g., minimized loss). The described shield can transfer thermal energy produced at least in part by the MMIC and other discrete components to the periphery of the PCB or to other components of the radar assembly. As a result, the described shield may permit the radar assembly to better distribute thermal energy away from relatively hot components (e.g., the MMIC) and to the rest of the PCB. The described shield may also enable the radar assembly to be manufactured in fewer steps than other radar assemblies that require, for example, the soldering of multiple layers to form the antenna waveguides.

This is just one example of how the described techniques and systems provide formed waveguide antennas of a radar assembly. This document describes other examples and configurations.

<FIG> illustrates an example environment <NUM> in which formed waveguide antennas <NUM> of a radar assembly <NUM> can be implemented. In the depicted environment <NUM>, the radar assembly <NUM> is mounted to, or integrated within, a vehicle <NUM>. The radar assembly <NUM> can detect one or more objects <NUM> that are near the vehicle <NUM>. Although illustrated as a car or automobile, the vehicle <NUM> can represent other types of motorized vehicles (e.g., an automobile, a motorcycle, a bus, a tractor, a semi-trailer truck, or construction equipment), non-motorized vehicles (e.g., a bicycle), railed vehicles (e.g., a train or a trolley car), watercraft (e.g., a boat or a ship), aircraft (e.g., an airplane or a helicopter), or spacecraft (e.g., satellite). In general, manufacturers can mount the radar assembly <NUM> to any moving platform, including moving machinery or robotic equipment, to detect the one or more objects <NUM>.

In the depicted implementation, the radar assembly <NUM> is mounted on the front of the vehicle <NUM> and provides a field-of-view <NUM> illuminating the one or more objects <NUM>. The radar assembly <NUM> can project the instrumental field-of-view <NUM> from or through any exterior surface of the vehicle <NUM>. For example, vehicle manufacturers can integrate the radar assembly <NUM> into a bumper, side mirror, headlights, rear lights, or any other interior or exterior location where the object <NUM> requires detection. In some cases, the vehicle <NUM> includes multiple radar assemblies <NUM>, such as a first radar assembly <NUM> and a second radar assembly <NUM> that together provide a larger field-of-view <NUM>. In general, vehicle manufacturers can design the locations of the radar assemblies <NUM> to provide a particular field-of-view <NUM> that encompasses a region of interest in which the object <NUM> may be present. Example fields-of-view <NUM> include a <NUM>-degree field-of-view, one or more <NUM>-degree fields-of-view, one or more <NUM>-degree field-of-view, and so forth, which can overlap or be combined into a field-of-view <NUM> of a particular size.

The object <NUM> is composed of one or more materials that reflect radar signals or electromagnetic (EM) signals. Depending on the application, the object <NUM> can represent a target of interest. In some cases, the object <NUM> can be a moving object or a stationary object. The stationary objects can be continuous (e.g., a concrete barrier, a guard rail) or discontinuous (e.g., a traffic cone) along a road portion.

The radar assembly <NUM> emits electromagnetic radiation by transmitting one or more electromagnetic signals or waveforms via active elements. In the environment <NUM>, the radar assembly <NUM> can detect and track the object <NUM> by transmitting and receiving one or more radar signals. As an example, the radar assembly <NUM> can transmit electromagnetic signals between <NUM> and <NUM> gigahertz (GHz), between <NUM> and <NUM>, or between approximately <NUM> and <NUM>.

The radar assembly <NUM> can determine a distance to the object <NUM> based on a time it takes for the EM signals to travel from the radar assembly <NUM> to the object <NUM> and from the object <NUM> back to the radar assembly <NUM>. The radar assembly <NUM> can also determine, based on the direction of a maximum amplitude echo signal received, the location of the object <NUM> in terms of an angle.

The radar assembly <NUM> can be part or integrated as part of the vehicle <NUM>. The vehicle <NUM> can also include at least one automotive system that relies on data from the radar assembly <NUM>, including a driver-assistance system, an autonomous-driving system, or a semi-autonomous-driving system. The radar assembly <NUM> can include an interface to the automotive system, wherein the formed waveguide antenna <NUM> can output, via the interface, a signal based on electromagnetic energy received by the formed waveguide antenna <NUM>. Generally, the automotive systems use radar data provided by the radar assembly <NUM> to perform a function. For example, the driver-assistance system can provide blind-spot monitoring and generate an alert indicating a potential collision with the object <NUM> detected by the radar assembly <NUM>. In this case, the radar data from the radar assembly <NUM> indicates when it is safe or unsafe to change lanes.

The autonomous-driving system may move the vehicle <NUM> to a particular location on the road while avoiding collisions with detected objects <NUM>. The radar data provided by the radar assembly <NUM> can provide information about a distance to and the location of the object <NUM> to enable the autonomous-driving system to perform emergency braking, perform a lane change, or adjust the speed of the vehicle <NUM>.

The radar assembly <NUM> includes a transmitter (not illustrated in <FIG>) to transmit electromagnetic signals and a receiver (not illustrated in <FIG>) to receive reflected versions of these electromagnetic signals. The transmitter includes components for emitting electromagnetic signals, including the formed waveguide antenna <NUM>. The receiver includes one or more components to detect the reflected electromagnetic signals, including the formed waveguide antenna <NUM>. Also sometimes referred to as a transceiver, the transmitter and the receiver can be separated or combined and may be incorporated together on the same integrated circuit (e.g., a transceiver integrated circuit) or, when separated, may be incorporated separately on different integrated circuits. The radar assembly <NUM> can also include other components and integrated circuits (e.g., an MMIC) to perform mixing, power amplification, low-noise amplification, high-frequency switching, and other functions on the transmitted and/or received electromagnetic signals.

The radar assembly <NUM> also includes one or more processors <NUM> and computer-readable storage media (CRM) <NUM>. The processor <NUM> can be a microprocessor or a system-on-chip. The processor <NUM> executes instructions stored within the CRM <NUM>. For example, the processor <NUM> can process electromagnetic energy received by the formed waveguide antenna <NUM> and locate the object <NUM> relative to the radar assembly <NUM>. The processor <NUM> can also generate radar data for automotive systems. As another example, the processor <NUM> can control, based on processed electromagnetic energy from the formed waveguide antenna <NUM>, an autonomous or semi-autonomous driving system of the vehicle <NUM>.

The described radar assembly <NUM> can minimize cost and improve performance characteristics for the waveguide antennas <NUM>. As described in greater detail with respect to <FIG>, the waveguide antennas <NUM> can be formed out of one or more metal sheets with multiple waveguide channels. In this way, the waveguide antennas <NUM> can be formed with materials and a manufacturing process that reduces costs while still providing high performance (e.g., minimized loss). The metal sheet can also be further configured to form a shield around the processor <NUM> or other discrete components of the radar assembly <NUM>. The described shield can transfer thermal energy produced at least in part by the processor <NUM> and other discrete components to the periphery of a PCB or to other components of the radar assembly <NUM>. As a result, the described shield may permit the radar assembly <NUM> to better distribute thermal energy away from relatively hot components (e.g., the processor <NUM>) and to the rest of the PCB. The described shield may also enable the radar assembly <NUM> to be manufactured in fewer steps than other radar assemblies that require, for example, the soldering of multiple layers to form the antenna waveguides.

<FIG> illustrates a cross-section of a not claimed example radar assembly <NUM> with formed waveguide antennas <NUM>. The radar assembly <NUM> includes multiple waveguide antennas <NUM>, a PCB <NUM>, a processor <NUM>, and a termination insensitive mixer (TIM) <NUM>. The multiple waveguide antennas <NUM> can, for example, include or be part of a transmitter and receiver for the radar assembly <NUM>. The transmitter, coupled with a waveguide antenna <NUM>, can transmit electromagnetic signals. The receiver, coupled with another waveguide antenna <NUM>, can receive reflected versions of the transmitted electromagnetic signals.

The PCB <NUM> is a circuit board, or other substrate, to which the waveguide antennas <NUM>, the processor <NUM>, and the CRM <NUM> can be attached. The PCB <NUM> can be a standard circuit board of flat laminated composite made from non-conductive substrate materials with one or more layers of copper circuitry. Other examples of the PCB <NUM> exist; the PCB <NUM> provides at least one surface for attaching the waveguide antennas <NUM>.

The PCB <NUM> can include multiple thermal vias <NUM> between the surfaces of the PCB <NUM>. A thermally conductive material <NUM> (e.g., copper circuit traces) covers at least a portion of the surfaces of the PCB <NUM> and the inner surface(s) of the thermal vias <NUM>. The thermally conductive material <NUM> can also cover the distal ends of the thermal vias <NUM>, as illustrated in <FIG>. The thermally conductive material <NUM> can be metal, including, for example, a copper alloy, and cover unpopulated areas of the surfaces of the PCB <NUM>.

The processor <NUM> can, for example, be an integrated circuit (IC), MMIC, or microprocessor. The processor <NUM> can operably connect via a ball grid array (BGA) to a surface of PCB <NUM> or another circuit board, which operably connects via another BGA to a surface of the PCB <NUM>. As illustrated in <FIG>, the thermally conductive material <NUM> covers the surface of the PCB <NUM> under the processor <NUM>. In another implementation, the thermally conductive material <NUM> does not cover the surface of the PCB <NUM> under the processor <NUM> to avoid interfering with the connection between the processor <NUM> and the PCB <NUM>. The TIM <NUM> is a microwave mixer that is a non-linear device used to translate one segment of the frequency spectrum of EM signals to another portion of the frequency spectrum without distorting the EM signals. In some implementations, the TIM <NUM> can be configured to provide cancellation of reflected EM signals as well as maintain the harmonics rejection, spurious component rejection, and port-to-port isolation characteristic of a double-balanced configuration. The TIM <NUM> can be collocated with the processor <NUM> (or a MMIC) to improve signal processing of the reflected EM signals and reduce reduction of additional noise into the reflected EM signals.

The waveguide antennas <NUM> are formed from one or more metal sheets. The metal sheets are sheet formed into one or more waveguide channels. The metal sheets can be made of an aluminum alloy, stainless steel, a copper alloy, or other metal alloys. The waveguide channels can be formed using a die, hydroforming techniques, or some other process. The waveguide antennas <NUM> are mounted to the PCB <NUM> using a conductive or non-conductive pressure-sensitive adhesive (PSA) <NUM>. In other implementations, the waveguide antennas <NUM> can be soldered or otherwise attached to the PCB <NUM>.

The waveguide antennas <NUM> are electrically coupled to a dielectric <NUM> via a floor <NUM> of the waveguide channels. Electromagnetic signals enter the waveguide channels through an opening in the waveguide channels and exit the waveguide channels via the radiation slots <NUM>. The waveguide channels of the waveguide antennas <NUM> provide a hollow channel <NUM> for the dielectric <NUM>. The dielectric <NUM> generally includes air, and the waveguide antennas <NUM> are air waveguide antennas.

The waveguide channels can form an approximately rectangular shape or a zigzag shape along a longitudinal direction. The cross-section of the waveguide channels can form an approximately rectangular shape. In other implementations, the cross-section of the waveguide channels can form an approximately square, oval, trapezoidal, or circular opening.

The waveguide channels include multiple radiation slots <NUM>. The radiation slots <NUM> can be bored, cut, etched, or punched through a top surface of the waveguide channels in accordance with predetermined patterns or configurations. The radiation slots <NUM> provide an opening through the metal sheet that defines a surface of the waveguide channels. The radiation slots <NUM> can have an approximately rectangular shape (e.g., a longitudinal slot parallel to a longitudinal direction of the waveguide channels). The radiation slots <NUM> can have other shapes, including approximately circular, oval, or square.

The radiation slots <NUM> can be sized and positioned on the waveguide channels to produce a particular radiation pattern for the waveguide antennas <NUM>. For example, at least some of the radiation slots <NUM> can be offset from a centerline of the waveguide channels by varying or non-uniform distances (e.g., in a zigzag shape) to reduce or eliminate side lobes from the radiation pattern of the waveguide antennas <NUM>. As another example, the radiation slots <NUM> nearer the closed end of the waveguide channels can have a larger longitudinal opening than the radiation slots <NUM> nearer the opening of the waveguide channels. The specific size and position of the radiation slots <NUM> can be determined by building and optimizing a model of the waveguide antennas <NUM> to produce the desired radiation pattern.

<FIG> illustrates a cross-section of a claimed example radar assembly <NUM> with formed waveguide antennas <NUM>. The radar assembly <NUM> is similar to the radar assembly <NUM> of <FIG>. Like the radar assembly <NUM> of <FIG>, the radar assembly <NUM> includes the multiple waveguide antennas <NUM>, the PCB <NUM>, an MMIC <NUM> (in lieu of the processor <NUM>), and the TIM <NUM>. In a not claimed example, the discrete components of the radar assembly <NUM> can be provided in other arrangements on one or more surfaces of the PCB <NUM>.

The waveguide antennas <NUM> are formed from a single metal sheet that forms multiple waveguide channels. The single metal sheet can be made of an aluminum alloy, stainless steel, or a copper alloy. The waveguide channels can be formed using a die, hydroforming techniques, or some other process. The metal sheet is also used to form an MMIC shield <NUM> for the MMIC <NUM> and the TIM <NUM>.

The MMIC shield <NUM> can distribute thermal energy produced by the MMIC <NUM> and the TIM <NUM> away from the components and to a housing (not illustrated in <FIG>) via the thermally conductive material <NUM> and the thermal vias <NUM>. The MMIC shield <NUM> can extend to unpopulated areas of the PCB <NUM> and thermally connects via the thermally conductive material <NUM> to a ground plane of the PCB <NUM>. The MMIC shield <NUM> can also prevent or suppress electromagnetic signals or radiation interfering with operations of the MMIC <NUM> and the TIM <NUM>.

In this way, the MMIC shield <NUM> enables the radar assembly <NUM> to have improved performance at times, when compared with the radar assembly <NUM>. In a noisy environment where electromagnetic signals or interference from another radar or other systems is present in and around the vehicle <NUM>.

<FIG> illustrates a cross-section of another not claimed example radar assembly <NUM> with formed waveguide antennas <NUM>. The radar assembly <NUM> is similar to the radar assembly <NUM> of <FIG> and the radar assembly <NUM> of <FIG>. Like the radar assembly <NUM> and the radar assembly <NUM>, the radar assembly <NUM> includes the multiple waveguide antennas <NUM>, the PCB <NUM>, and the MMIC <NUM>. The discrete components of the radar assembly <NUM> can be provided in other arrangements on one or more surfaces of the PCB <NUM>.

In this implementation, the waveguide antennas <NUM> are attached or connected to a different surface of the PCB <NUM> than the MMIC <NUM>. In other implementations, the MMIC <NUM> and the waveguide antennas can connect or be attached to the same surface of the PCB <NUM>.

The waveguide antennas <NUM> are formed from multiple metal sheets. The metal sheets can be an aluminum alloy, stainless steel, a copper alloy, or other metal alloy. The metal sheets are connected together via a braze <NUM>. For example, the metal sheets can be brazed together using aluminum braze or another brazing material. In other implementations, the metal sheets can be connected together using shear forming, a stake-and-rollover process, spot welding, and/or lamination cladding.

The waveguide channels <NUM> and radiation slots <NUM> can be formed by stamping or otherwise removing portions of the metal sheets. The waveguide antennas <NUM> are mounted to the PCB <NUM> using a conductive or non-conductive PSA <NUM>. In other implementations, the waveguide antennas <NUM> can be soldered or otherwise attached to the PCB <NUM>. As described above, the waveguide channels and radiation slots can be sized and arranged to generate a desired radiation pattern.

Use of the radar system <NUM>, <NUM>, or <NUM> can depend on the application. For example, where a particular form factor is desired, the radar system <NUM> may provide the most flexibility in designing a layout for the PCB <NUM>. The radar systems <NUM> and <NUM> may provide a cheaper or more expensive solution, depending on a desired accuracy in the radar data, for example.

<FIG> illustrate several views and layers of an example formed waveguide antenna. As described with respect to <FIG>, the waveguide antenna can be formed from several metal sheets. <FIG> illustrate a cross-section view <NUM> and a three-dimensional (3D) perspective view <NUM> of the layers of the formed waveguide antenna.

<FIG> illustrate a perspective view <NUM>-<NUM> and a top view <NUM>-<NUM> of a first layer <NUM> of the formed waveguide antenna. As described with respect to <FIG>, the first layer <NUM> includes the radiation slots <NUM>. The radiation slots <NUM> are sized and positioned on or in the first layer <NUM> to produce a particular radiation pattern. For example, the plurality of radiation slots <NUM> can be evenly distributed along the waveguide channels to suppress grating lobes in the radiation pattern. The first layer <NUM> also includes several alignment holes <NUM> that can be used to align the metal sheets during the brazing or other connection procedure.

<FIG> illustrate a perspective view <NUM>-<NUM> and a top view <NUM>-<NUM> of a second layer <NUM> of the formed waveguide antenna. As described with respect to <FIG>, the second layer <NUM> includes waveguide channels <NUM>. The second layer <NUM> also includes the alignment holes <NUM> to align the first layer <NUM> and the second layer <NUM> during the brazing or other connection procedure. As illustrated in <FIG>, the waveguide channels <NUM> have a zigzag shape along a longitudinal direction of the waveguide channels. The zigzag shape of the waveguide channels <NUM> can reduce or eliminate grating lobes in the radiation pattern that a straight or rectangular waveguide channel shape can introduce. The turns in the zigzag shape can include various turning angles to provide the zigzag shape. The zigzag shape of the waveguide channels <NUM> allows the radiation slots <NUM> to be positioned in an approximately straight line along the longitudinal direction of the waveguide channels.

<FIG> illustrates the cross-section view <NUM> of the formed waveguide channel. As illustrated in <FIG>, the alignment holes <NUM> of the first layer <NUM> and the second layer <NUM> are aligned during the connection process. The radiation slots <NUM> of the first layer <NUM> are positioned over (or under) the waveguide channels <NUM> of the second layer <NUM>.

<FIG> illustrates the 3D perspective view <NUM> of the formed waveguide channel. As illustrated in <FIG>, the alignment holes <NUM> of the first layer <NUM> and the second layer <NUM> are aligned during the connection process. The radiation slots <NUM> of the first layer <NUM> are positioned over (or under) the waveguide channels <NUM> of the second layer <NUM>; thus, the radiation slots <NUM> are connected to the dielectric <NUM> (e.g., air) contained with the hollow channel <NUM> of the waveguide channels <NUM>.

<FIG> illustrates a top view <NUM> of another example formed waveguide antenna <NUM>. <FIG> illustrates a cross-section view <NUM> of the formed waveguide antenna <NUM>. The waveguide antenna <NUM> includes a waveguide channel <NUM> and the radiation slots <NUM>.

The waveguide <NUM> includes a first layer <NUM>, a second layer <NUM>, and a third layer <NUM>. The first layer <NUM> and the second layer <NUM> can be formed from metal sheets, as described above with respect to <FIG>. The third layer <NUM> can be the thermally-conductive material <NUM> or the PCB <NUM>. The second layer <NUM> and the third layer <NUM> form sides and the floor, respectively, of the waveguide channel <NUM>. The first layer <NUM> and the second layer <NUM> are separate layers in the depicted implementation. In other implementations, the first layer <NUM> and the second layer <NUM> can be formed as a single layer and combined with the PCB structure to form the waveguide channel <NUM>.

The use of the PCB structure allows manufacturing of the waveguide antenna <NUM> to be cheaper, less complicated, and easier for mass production. As another example, using a PCB provides low loss of EM radiation from the input of the waveguide channel <NUM> to radiation from the radiation slots <NUM>.

The waveguide channel <NUM> can include a hollow channel for a dielectric. The dielectric generally includes air, and the waveguide antenna <NUM> is an air waveguide. The waveguide channel <NUM> forms an opening in a longitudinal direction <NUM> at one end of the waveguide antenna <NUM> and a closed wall at an opposite end. In the depicted implementation, the waveguide antenna <NUM> includes a single waveguide channel <NUM>, but the waveguide antenna <NUM> can include multiple waveguide channels <NUM> in other implementations. EM signals enter the waveguide channel <NUM> through the opening and exit the waveguide channel <NUM> via the radiation slots <NUM>. In <FIG>, the waveguide channel <NUM> forms an approximately rectangular shape in the longitudinal direction <NUM>. The waveguide channel <NUM> can also form a zigzag shape in the longitudinal direction <NUM>.

As depicted in <FIG>, the waveguide channel <NUM> can form an approximately rectangular opening in the cross-section view <NUM> of the waveguide antenna <NUM>. In other implementations, the waveguide channel <NUM> can form an approximately square, oval, or circular opening in the cross-section view <NUM> of the waveguide antenna <NUM>. In other words, the opening to the waveguide channel <NUM> can have an approximately square shape, oval shape, or circular shape.

The radiation slots <NUM> are sized and positioned on the first layer <NUM> to produce a particular radiation pattern for the antenna. For example, at least some of the radiation slots <NUM> are offset from the longitudinal direction <NUM> (e.g., a centerline of the waveguide channel <NUM>) by varying or non-uniform distances (e.g., in a zigzag shape) to reduce or eliminate side lobes from the radiation pattern of the waveguide antenna <NUM>. As another example, the radiation slots <NUM> nearer the wall at the opposite end of the waveguide channel <NUM> can have a larger longitudinal opening than the radiation slots <NUM> nearer the opening of the waveguide channel <NUM>. The specific size and position of the radiation slots <NUM> can be determined by building and optimizing a model of the waveguide antenna <NUM> to produce the desired radiation pattern.

The plurality of radiation slots <NUM> is evenly distributed along the waveguide channel <NUM> between the opening of the waveguide channel and the closed wall. Each adjacent pair of radiation slots <NUM> are separated along the longitudinal direction <NUM> by a uniform distance to produce a particular radiation pattern. The uniform distance, which is generally less than one wavelength of the EM radiation, can prevent grating lobes in the radiation pattern.

<FIG> depicts a not claimed example method <NUM> of assembling a radar assembly <NUM> with formed waveguide antennas <NUM>. Method <NUM> is shown as sets of operations (or acts) performed, but not necessarily limited to the order or combination in which the operations are shown herein. Further, any of one or more of the operations may be repeated, combined, or reorganized to provide other methods. In portions of the following discussion, reference may be made to the radar assembly <NUM> of <FIG> or the radar assemblies of <FIG>, respectively, and entities detailed therein, reference to which is made for example only. The techniques are not limited to performance by one entity or multiple entities.

At <NUM>, one or more metal sheets are formed into one or more waveguide antennas. Each of the one or more waveguide antennas includes multiple waveguide channels with multiple radiation slots. The multiple radiation slots are arranged in a surface of each of the multiple waveguide channels through to the multiple waveguide channels. For example, the radar assembly <NUM> includes a single metal sheet formed into two waveguide antennas <NUM>. Each waveguide antenna <NUM> includes multiple waveguide channels with multiple radiation slots <NUM>. The radiation slots <NUM> are arranged in a surface of the multiple waveguide channels and through to the hollow channel <NUM> of the waveguide channels to generate a desired radiation pattern. As another example, the radar assembly <NUM> includes three metal sheets formed into two waveguide antennas <NUM>. The waveguide antennas <NUM> include multiple waveguide channels with multiple radiation slots <NUM>. The metal sheets can be brazed together to form the waveguide antennas <NUM>.

At <NUM>, the one or more metal sheets are positioned adjacent to a first surface of a PCB. The PCB includes an IC and a thermally conductive material that covers at least a portion of the first surface and a second surface of the PCB. The second surface of the PCB is opposite the first surface of the PCB. For example, the radar assembly <NUM> includes the one or more metal sheets positioned adjacent to a first surface of the PCB <NUM>. The PCB <NUM> includes the processor <NUM> and the thermally conductive material <NUM>, which covers at least a portion of the first surface and the second surface of the PCB <NUM>. The second surface of the PCB <NUM> is opposite the first surface of the PCB <NUM>. In other implementations, the PCB <NUM> can also include an MMIC <NUM> and/or a TIM <NUM>. As another example, the radar assembly <NUM> includes the three metal sheets positioned adjacent to a first surface of the PCB <NUM>. The PCB <NUM> includes the MMIC <NUM> attached to the second surface of the PCB <NUM>.

At <NUM>, a shield is optionally positioned adjacent to the IC and at least one of the first surface or the second surface of the PCB. The shield is configured to distribute thermal energy produced by the IC away from the IC. For example, the radar assembly <NUM> also includes the MMIC shield <NUM> positioned adjacent to the MMIC <NUM> and the TIM <NUM> and the first surface of the PCB <NUM>. The shield <NUM> is configured to distribute thermal energy produced by the MMIC <NUM> and/or the TIM <NUM> away from the MMIC <NUM>.

At <NUM>, the one or more metal sheets and the PCB are attached together to form the radar system. For example, the metal sheet of the waveguide antennas <NUM> and the PCB <NUM> are attached, including using PSA <NUM>, to form the radar assembly <NUM>. As another example, the three metal sheets for the waveguide antennas <NUM> and the PCB <NUM> are attached, including using PSA <NUM>, to form the radar assembly <NUM>.

In the following section, examples are provided.

Example <NUM>: A radar assembly comprising: a printed circuit board (PCB) having a first surface and a second surface, the PCB including an integrated circuit, IC, attached to the first surface and and a thermally conductive material that covers at least a portion of the first surface and second surface of the PCB opposite the first surface of the PCT; and a single metal sheet attached to the first surface of the PCB, the single metal sheet configured into multiple waveguide antennas and a shield, each of the multiple waveguide antennas including multiple waveguide channels with multiple radiation slots, the multiple radiation slots being arranged in a surface of the single metal sheet through to the multiple waveguide channels, the shield being adjacent to the IC and configured to distribute thermal energy produced at least in part by the IC away from the IC.

Example <NUM>: The radar assembly of example <NUM>, the radar assembly further comprising a termination insensitive mixer attached to the IC and in contact with the shield, wherein the shield encapsulates the IC and the termination insensitive mixer.

Example <NUM>: The radar assembly of of example <NUM> or <NUM>, wherein: the IC is a monolithic microwave integrated circuit (MMIC); the PCB further includes multiple thermal vias between the first surface of the PCB and the second surface of the PCB, the multiple thermal vias configured to distribute thermal energy produced at least in part by the MMIC from the first surface of the PCB to the second surface of the PCB; and the thermally conductive material covers an inner surface of the thermal vias.

Example <NUM>: The radar assembly of example <NUM>, wherein the thermally conductive material also covers a first distal end and a second distal end of the thermal vias to distribute the thermal energy produced at least in part by the MMIC along the first surface of the PCB.

Example <NUM>: The radar assembly of example <NUM>, wherein a first distal end and a second distal end of the thermal vias are not covered by the thermally conductive material.

Example <NUM>: The radar assembly of any one of examples <NUM> through <NUM>, wherein the thermally conductive material comprises circuit traces formed of metal.

Example <NUM>: The radar assembly of any one of examples <NUM> through <NUM>, wherein the thermally conductive material and the single metal sheet include at least one of an aluminum alloy, stainless steel, or a copper alloy.

Example <NUM>: The radar assembly of any one of the preceding examples, wherein the radar assembly is configured to be installed on an automobile to detect objects in an environment of the automobile.

Example <NUM>: A method of assembling a radar system, the method comprising: forming a single metal sheets into multiple waveguide antennas and a shield, each of the multiple waveguide antennas including multiple waveguide channels with multiple radiation slots, the multiple radiation slots being arranged in a surface of each of the multiple waveguide channels through to the multiple waveguide channels; positioning the single metal sheet adjacent to a first surface of a printed circuit board (PCB), the PCB including an integrated circuit (IC) and a thermally conductive material that covers at least a portion of the first surface of the PCB and at least a portion of a second surface of the PCB opposite the first surface of the PCB; and attaching together the single metal sheets and the PCB to form the radar system.

Example <NUM>: The method of example <NUM>, wherein the waveguide channels are formed in the single metal sheet by use of at least one of a die or a hydroforming technique.

Example <NUM>: The method of example <NUM>, wherein the single metal sheet is attached to the PCB by a pressure-sensitive adhesive.

Example <NUM>: The method of example <NUM>, the method further comprising: forming the single sheet into a shield, the shield being adjacent to the IC and configured to distribute thermal energy produced at least in part by the IC away from the IC.

Example <NUM>: The method of example <NUM>, wherein: a termination insensitive mixer is attached to the IC; and the shield is adjacent to the IC and the termination insensitive mixer.

Example <NUM>: The method of example <NUM>, wherein: the IC is a monolithic microwave integrated circuit (MMIC) and is positioned on the first surface of the PCB; the PCB further includes multiple thermal vias between the first surface of the PCB and the second surface of the PCB, the multiple thermal vias configured to distribute thermal energy produced at least in part by the MMIC from the first surface of the PCB to the second surface of the PCB; and the thermally conductive material covers an inner surface of the thermal vias.

Example <NUM>: The method of example <NUM>, wherein the thermally conductive material and the single metal sheet include at least one of an aluminum alloy, stainless steel, or a copper alloy.

Example <NUM>: A method of assembling a radar system, the method comprising: forming a single metal sheet into multiple waveguide antennas of the radar assembly of any one of claims <NUM> through <NUM>; positioning the single metal sheet adjacent to a first surface of a printed circuit board (PCB), the PCB including an integrated circuit (IC) and a thermally conductive material that covers at least a portion of the first surface of the PCB and at least a portion of a second surface of the PCB opposite the first surface of the PCB; and attaching together the single metal sheet and the PCB to form the radar system.

Claim 1:
A radar assembly (<NUM>) comprising:
a printed circuit board, PCB (<NUM>), having a first surface and a second surface, the PCB (<NUM>) including an integrated circuit, IC, attached to the first surface and a thermally conductive material (<NUM>) that covers at least a portion of the first surface and second surface of the PCB (<NUM>) opposite the first surface of the PCB (<NUM>); and
a single metal sheet attached to the first surface of the PCB (<NUM>), the single metal sheet configured into multiple waveguide antennas (<NUM>) and a shield (<NUM>), each of the multiple waveguide antennas (<NUM>) including multiple waveguide channels (<NUM>, <NUM>) with multiple radiation slots (<NUM>), the multiple radiation slots (<NUM>) being arranged in a surface of the single metal sheet through to the multiple waveguide channels (<NUM>, <NUM>), the shield (<NUM>) being adjacent to the IC and configured to distribute thermal energy produced at least in part by the IC away from the IC.