Waveguide Launcher

Abstract

A transceiver includes a first electrical channel and a second electrical channel. The first electrical channel is configured to transmit an electromagnetic signal to a first air waveguide. Each of the first electrical channels extends from a transmitter along an outer surface of a chip package supporting the transmitter and terminates at a first transition portion on the outer surface. Each of the first plurality of air waveguides is attached to the outer surface and covers one of the first transition portions. The transceiver also includes a second electrical channel configured to transmit a second electromagnetic signal from the second air waveguide. Each of the second electrical channels extends from a receiver along an outer surface of a chip package supporting the receiver and terminates at a second transition portion on the outer surface. Each of the second air waveguides is attached to the outer surface and covers one of the second transition portions.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 839,904, filed on April 29, 2019, which is hereby incorporated by reference in its entirety. Technical Field

[0003] The present disclosure generally relates to waveguide transmitters for millimeter wave radar. Background Art

[0004] A typical radar assembly includes a printed circuit board (PCB) placed between the radar chip package and the radar waveguide to facilitate the connection between the devices. The PCB introduces electrical losses, which reduces the transmission range and reception range of the radar signal. Summary of the invention

[0005] The present disclosure proposes to solve the above-mentioned problem by providing a transceiver, the transceiver comprising a first plurality of electrical channels configured to transmit a first electromagnetic signal to a first plurality of air waveguides; wherein each of the first plurality of electrical channels extends from an output of at least one transmitter along an outer surface of a chip package supporting the at least one transmitter and terminates at a first transition portion provided on the outer surface; wherein each of the first plurality of air waveguides is attached to the outer surface and covers one of the first transition portions.

[0006] Other advantageous features according to the invention are:

[0007] -The transceiver further includes a second plurality of electrical channels configured for transmitting a second electromagnetic signal from a second plurality of air waveguides; wherein each of the second plurality of electrical channels extends from an input of the at least one receiver along an outer surface of a chip package supporting the at least one receiver and terminates at a second transition portion disposed on the outer surface; wherein each of the second plurality of air waveguides is attached to the outer surface and covers one of the second transition portions.

[0008] - the first plurality of electrical channels comprises differential microstrip pairs;

[0009] - the first transition portion includes a pair of opposing solder ball transition portions;

[0010] - the first plurality of air guides comprises slotted air guides;

[0011] - the first transition section comprises a loop transition section;

[0012] - the first transition portion comprises a bow tie transition portion;

[0013] - the first plurality of electrical channels comprises coplanar waveguides;

[0014] - the first transition section comprises a monopolar transition section;

[0015] - the first transition section comprises a loop transition section;

[0016] - the first transition portion comprises a patch transition portion;

[0017] - a second plurality of electrical channels comprising differential microstrip pairs;

[0018] - the second transition portion includes a pair of opposing solder ball transition portions;

[0019] - the second plurality of air guides comprises slotted air guides;

[0020] - the second transition section comprises a loop transition section;

[0021] - the second transition portion comprises a bow tie transition portion;

[0022] - the second plurality of electrical channels comprises coplanar waveguides;

[0023] - the second transition section comprises a monopolar transition section;

[0024] - the second transition section comprises a loop transition section;

[0025] - the second transition portion comprises a patch transition portion;

[0026] - the chip package includes at least four receivers;

[0027] - The chip package comprises at least three emitters. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0029] Figure 1 is a diagram of a transceiver according to one embodiment;

[0030] Figure 2A is a diagram of an electrical channel and a transition according to one embodiment;

[0031] Figure 2B is a diagram of an electrical channel and a transition portion according to another embodiment;

[0032] Figure 2C is a diagram of an electrical channel and a transition portion according to yet another embodiment;

[0033] Figure 3A is a diagram of an electrical channel and a transition portion according to yet another embodiment;

[0034] Figure 3B is a diagram of an electrical channel and a transition portion according to yet another embodiment;

[0035] Figure 3C is a diagram of an electrical channel and a transition according to yet another embodiment; and

[0036] Figure 4 According to an embodiment Figure 1 Cross section of a transceiver. DETAILED DESCRIPTION

[0037] Reference will now be made in detail to the embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of each described embodiment. However, it will be apparent to one of ordinary skill in the art that each described embodiment may be practiced without these specific details. In other instances, well-known methods, procedures, components, circuits, and networks are not described in detail in order to avoid unnecessarily obscuring aspects of the embodiments.

[0038] Figure 1 1 is a diagram of a transceiver 10 configured to transmit and receive electromagnetic signals. In an example, the transceiver 10 transmits and receives electromagnetic signals in a frequency band of 76 GHz to 81 GHz, such as electromagnetic signals used in automotive radar systems. The transceiver 10 includes a chip package 12, which includes a die 13, which includes at least one transmitter 14 and at least one receiver 16. The at least one transmitter 14 and the at least one receiver 16 communicate with the chip package 12 via an antenna 18 (see FIG. 1 ). Figure 4 ) to send and receive electromagnetic signals (i.e., radar signals). Figure 1 , the chip package 12 is a monolithic microwave integrated circuit (MMIC) having a ball grid array (BGA) of interconnects (not shown) on an outer surface 20. In this example, the chip package 12 supports three transmitters 14 and four receivers 16. It will be appreciated that the chip package 12 may support any number of transmitters 14 and receivers 16 within the size constraints of the chip package 12.

[0039] An air waveguide 22 is placed between the chip package 12 and the antenna 18 to transmit the radar signals being sent and received. The air waveguide 22 is a hollow metal structure that is capable of directing electromagnetic power from one area to another. The transceiver 10 is an improvement over other transceivers because the transceiver 10 eliminates the intermediate printed circuit board (PCB) that can be placed between the chip package and the waveguide to facilitate the connection between the devices. The PCB introduces electrical losses that reduce the transmission range and reception range of the radar signal. In addition, the inclusion of the PCB increases material and manufacturing costs.

[0040] Reference again Figure 1, the transceiver 10 includes a first plurality of electrical channels 24 (ie, signal transmission lines) configured to transmit a first electromagnetic signal to a first plurality of air waveguides 22A. Figure 1 In the example shown in , the first electromagnetic signal is a transmitted radar signal, and the air waveguide 22 is a WR10 air waveguide 22. WR10 specifies that the waveguide is rectangular and has dimensions of 2.54mm x 1.27mm. Slight variations in these dimensions do not significantly degrade the performance of the waveguide, and the rectangle does not have to be a "perfect" rectangle. The dimensions of the air waveguide 22 establish restrictions on the frequency of the electromagnetic signal that can pass through the air waveguide 22. The air waveguide 22 can be formed by a curved path (i.e., a bend) to guide the radar signal to the antenna 18 that can be arranged in an antenna array or to guide the radar signal from the antenna 18.

[0041] Each of the first plurality of electrical channels 24 extends from the output of at least one emitter 14 along the outer surface 20 of the chip package 12. That is, the first plurality of electrical channels 24 extend along the exterior of the chip package 12 and are exposed to the environment (e.g., air). In some configurations, this exposure results in about half of the guided power being propagated into the outer surface 20 and about half of the guided power being propagated into the air. Because air has little loss, this configuration ensures low transmission line losses.

[0042] The first plurality of electrical channels 24 terminate at a first transition 26 disposed on the outer surface 20. The first transition 26 is a link between the transmission line and the air waveguide 22, and will be described in more detail below. Each of the first plurality of air waveguides 22A is attached to the outer surface 20 of the chip package 12 and covers one of the first transitions 26. In the example, the first plurality of air waveguides 22A are integrated into a waveguide antenna assembly that is attached to the outer surface 20 of the chip package 12. In this example, the ends of the first plurality of air waveguides 22A are arranged within the surface of the waveguide antenna assembly to cover the first transition 26. The ends of the first plurality of air waveguides 22A covering the first transition 26 may be open, or may be partially closed (e.g., slotted), as will be described in more detail below.

[0043] The transceiver 10 also includes a second plurality of electrical channels 28 configured to transmit second electromagnetic signals from the second plurality of air waveguides 22B. Figure 1, the second electromagnetic signal is a received radar signal (i.e., a radar signal reflected from a target), and the air waveguide 22 is a WR10 air waveguide 22. Each of the second plurality of electrical channels 28 extends from the input of at least one receiver 16 along the outer surface 20 of the chip package 12. The second plurality of electrical channels 28 terminate at a second transition portion 30 disposed on the outer surface 20. Each of the second plurality of air waveguides 22B is attached to the outer surface 20 and covers one of the second transition portions 30. In the example, the second plurality of air waveguides 22B are integrated into a waveguide antenna assembly that is attached to the outer surface 20 of the chip package 12. In this example, the ends of the second plurality of air waveguides 22B are arranged within the surface of the waveguide antenna assembly to cover the second transition portion 30. The ends of the second plurality of air waveguides 22B covering the second transition portion 30 may be open, or may be partially closed (e.g., slotted), as will be described in more detail below.

[0044] Figure 2A-2C An example of a first plurality of electrical channels 24 and / or a second plurality of electrical channels 28 including differential microstrip pairs 32 is shown. The differential microstrip pairs 32 are formed of two parallel metal strips having a constant spacing along their length. One of the metal strips is connected to the positive terminal of the corresponding transceiver 10 channel, and the other metal strip is connected to the negative terminal of the corresponding transceiver 10 channel. The microstrips 32 are formed of a metal such as copper, aluminum, silver, gold, and alloys thereof, and may be formed on the outer surface 20 by any known deposition method such as physical vapor deposition. Techniques such as photolithography and / or micromachining may be used to separate the microstrips 32. In Figure 2A-2C In the example shown in FIG. 1 , the differential microstrip pair 32 terminates in an area of ​​the outer surface 20 of the chip package 12 surrounded by a solder ball fence 33. One end of the solder ball fence 33 defines a gap (i.e., a "mouse hole") through which the differential microstrip pair 32 passes. The solder ball fence 33 provides electromagnetic shielding for the air waveguide 22.

[0045] Figure 3A-3C An example of a first plurality of electrical channels 24 and a second plurality of electrical channels 28 including coplanar waveguides 34 is shown. The coplanar waveguides 34 are formed of three parallel metal strips having a constant spacing along their length. The center metal strip is connected to the positive terminal of the corresponding transceiver 10 channel, and the other two metal strips are attached to the negative terminals of the corresponding transceiver 10 channels. The coplanar waveguides 34 are formed of a metal, such as copper, aluminum, silver, gold, and alloys thereof, and may be applied to the outer surface 20 by any known deposition method, such as physical vapor deposition. Techniques such as photolithography and / or micromachining may be used to separate the coplanar waveguides 34. In Figure 3A-3CIn the example shown in FIG. 1 , the coplanar waveguide 34 also terminates in the area of ​​the outer surface 20 of the chip package 12 surrounded by the solder ball fence 33. One side of the solder ball fence 33 defines a gap through which the coplanar waveguide 34 passes. The coplanar waveguide 34 is arranged so that a 90-degree bend occurs before passing through the gap, which helps to convert the electromagnetic signal from the coplanar waveguide 34 to the air waveguide 22. That is, the 90-degree bend aligns the polarization of the coplanar waveguide 34 with the air waveguide 22 to achieve maximum conversion efficiency.

[0046] In an example, the first plurality of electrical channels 24 and the second plurality of electrical channels 28 have the same design (i.e., all differential microstrip pairs 32 or all coplanar waveguides 34). In another example, the first plurality of electrical channels 24 and the second plurality of electrical channels 28 have different designs. In an example, the first plurality of electrical channels 24 and the second plurality of electrical channels 28 terminate at first transitions 26 and second transitions 30 of the same design. In another example, the first plurality of electrical channels 24 and the second plurality of electrical channels 28 terminate at first transitions 26 and second transitions 30 of different designs. The following description of the first plurality of electrical channels 28, the first transitions 26, and the first plurality of air waveguides 22A will also apply to the second plurality of electrical channels 28, the second transitions 30, and the second plurality of air waveguides 22B.

[0047] Figure 2A A differential microstrip pair 32 is shown terminating at a first transition 26, which includes a pair of opposing solder ball transitions 36. The pair of opposing solder ball transitions 36 can be formed of any solder alloy compatible with the chip package 12, such as an alloy of silver and / or an alloy of gold. In this example, the first plurality of air waveguides 22A includes a slotted air waveguide 22C, wherein the slot is located between the pair of opposing solder ball transitions 36. In this example, in addition to the slot, the ends of the slotted air waveguide 22C covering the pair of opposing solder ball transitions 36 are closed. The pair of opposing solder ball transitions 36 are in electrical contact with the slotted ends of the slotted air waveguide 22C. The slot is an opening in the end of the slotted air waveguide 22C and interrupts the electric and magnetic fields established between the solder balls. This interruption in the field enables the radar signal to propagate through the slotted air waveguide 22C along a specific axis.

[0048] Figure 2BA differential microstrip pair 32 is shown, which terminates at a first transition 26 including a loop transition 38A. In this example, the loop transition 38A is a continuous rectangular metal loop that connects the differential microstrip pair 32. The loop transition 38A can be formed of a metal, such as copper, aluminum, silver, gold, and alloys thereof. In this example, the end of the air waveguide 22A covering the loop transition 38A is open. The circumference of the loop transition 38A is equal to approximately one wavelength of the radar signal. The magnetic field around the loop transition 38A generated by the current flowing through the loop generates an electromagnetic signal, which is transmitted through the air waveguide 22A.

[0049] Figure 2C A differential microstrip pair 32 is shown, which terminates at a first transition 26 including a bowtie transition 40. The bowtie transition 40 can be formed of a metal, such as copper, aluminum, silver, gold, and alloys thereof. In this example, the bowtie transition 40 is a triangular metal pad that contacts the differential microstrip pair 32. In this example, the end of the air waveguide 22A covering the bowtie transition 40 is open. The angle between the opposing triangular metal pads of the bowtie transition 40 specifies the frequency bandwidth of the first transition 26, rather than the perimeter size. The bowtie transition 40 is capable of operating over a wider frequency range than the loop transition 38A.

[0050] Figure 3A A coplanar waveguide 34 is shown terminating at the first transition 26 including a monopole transition 42. The monopole transition 42 is formed by extending the coplanar waveguide 34 into the region covered by the end of the air waveguide 22. The monopole transition 42 can be formed of a metal, such as copper, aluminum, silver, gold, and alloys thereof. In this example, the end of the air waveguide 22A covering the monopole transition 42 is open. In this example, the length of the positive band (i.e., the monopole) extending into the region covered by the air waveguide 22 is equal to about one-quarter of the radar signal wavelength. The two negative bands on both sides of the monopole form a ground plane. The magnetic field around the monopole transition 42 generated by the voltage potential between the monopole and the ground plane generates an electromagnetic signal transmitted through the air waveguide 22A.

[0051] Figure 3BA coplanar waveguide 34 is shown, which terminates at a first transition 26 including a loop transition 38B. In this example, the loop transition 38B includes a continuous rectangular metal loop connecting the two negative strips of the coplanar waveguide 34 and bifurcated by the positive strip of the coplanar waveguide 34, thereby creating two loops with equal circumferences. The loop transition 38B can be formed of a metal, such as copper, aluminum, silver, gold, and alloys thereof. In this example, the end of the air waveguide 22A covering the loop transition 38B is open. The circumference of each of the two loops in the loop transition 38B is approximately half the wavelength of the radar signal. The magnetic field around the loop transition 38B created by the current flowing through the two loops generates an electromagnetic signal, which is transmitted through the air waveguide 22A.

[0052] Figure 3C A coplanar waveguide 34 is shown terminating at a first transition 26 including a patch transition 44. The patch transition 44 may be formed of a metal, such as copper, aluminum, silver, gold, and alloys thereof. In this example, the end of the air waveguide 22A covering the patch transition 44 is open. In this example, the patch transition 44 is a rectangular metal pad that contacts the positive strip of the coplanar waveguide 34. The two negative strips form a ground plane. The length of the patch transition 44 is approximately half a wavelength, and the patch transition 44 radiates electromagnetic energy into the air waveguide 22 similar to the antenna 18. The magnetic field around the patch transition 44 created by the voltage potential between the patch and the ground plane generates an electromagnetic signal transmitted through the air waveguide 22A.

[0053] Figure 4 1 is a cross-sectional view of transceiver 10 showing an example of an antenna assembly attached to an outer surface 20 of chip package 12. In this example, air waveguide 22 is integrated into the antenna assembly and guides radar signals between first transition 26 and antenna 18. In this example, antenna 18 is a plurality of slots that radiate and / or collect radar signals. In this example, solder balls from a BGA are used to attach the antenna assembly to chip package 12.

[0054] Although the present invention has been described according to the preferred embodiments of the present invention, it is not intended to be limited thereto, but only to the scope set forth in the appended claims. "One or more" includes: a function performed by one element; a function performed by more than one element, for example, in a distributed manner; several functions performed by one element; several functions performed by several elements; or any combination of the above. It will also be understood that, although in some instances, the terms first, second, etc. are used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first contact may be referred to as a second contact, and similarly, a second contact may be referred to as a first contact without departing from the scope of each described embodiment. Both the first contact and the second contact are contacts, but they are not the same contact. The terms used in the description of the various described embodiments herein are only for the purpose of describing specific embodiments and are not intended to be restrictive. As used in the description of the various described embodiments and the appended claims, the singular forms "a", "an", and "the" are intended to also include plural forms unless the context clearly indicates otherwise. It will also be understood that the term "and / or" as used herein refers to and encompasses any one of the associated listed items and all possible combinations of one or more of the associated listed items. It will be further understood that the terms "include," "including," "comprise," and / or "comprising" when used in this specification specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the term "if" is optionally interpreted to mean "when or "after" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (the stated condition or event) is detected" are optionally interpreted to mean "after determining" or "in response to determining" or "after detecting (the stated condition or event)" or "in response to detecting (the stated condition or event)", depending on the context. Directional terms such as top, bottom, above, below, left, right, front, back, etc. do not indicate any particular orientation, but rather, these terms are used to distinguish one element from another and to establish a relationship between the various elements.

Claims

1. A transceiver, comprising: A plurality of electrical channels configured to transmit electromagnetic signals to a plurality of air waveguides, each of the plurality of electrical channels comprising a differential microstrip pair having a first microstrip and a second microstrip, the first microstrip being connected to a positive terminal of a corresponding transceiver channel and the second microstrip being connected to a negative terminal of the corresponding transceiver channel, the plurality of electrical channels comprising an electrical channel terminating at a transition portion, the transition portion providing a link between the electrical channel and an air waveguide covering the transition portion, the transition portion comprising an area of ​​an outer surface of a chip package, the chip package being configured to support at least one transmitter or at least one receiver, the area being covered by an end of the air waveguide, the area being surrounded by a solder ball fence, the solder ball fence being configured to provide electromagnetic shielding for the air waveguide, the solder ball fence defining a gap through which the differential microstrip pair passes, the transition portion comprising an arrangement selected from the group consisting of: a pair of opposed solder ball transitions in electrical contact with the ends of the waveguide on opposite sides of the slot, the end of the air waveguide covering the region including the slot, the slot being positioned between the pair of opposed solder ball transitions; as well as At least one bowtie transition section includes opposing triangular metal pads in contact with the differential microstrip pair, and the end of the air waveguide covering the region is open.

2. The transceiver according to claim 1, characterized in that: The slot is configured to interrupt a magnetic field established between the opposing solder ball transitions and enable radar signals to pass through the air waveguide.

3. The transceiver according to claim 1, wherein: The at least one bow tie transition comprises: a first triangular metal pad, the first triangular metal pad being in contact with the first microstrip; and A second triangular metal pad is in contact with the second microstrip and is positioned opposite to the first triangular metal pad.

4. The transceiver according to claim 3, characterized in that The angle formed between the opposing triangular metal pads specifies the frequency bandwidth of the transition portion.

5. The transceiver according to claim 1, wherein: The opposing solder ball transition portion includes a first solder ball and a second solder ball; The first microstrip terminates at the first solder ball; and The second microstrip terminates at the second solder ball.

6. A transceiver, comprising: A plurality of electrical channels configured to transmit electromagnetic signals to a plurality of air waveguides, each of the plurality of electrical channels comprising a coplanar waveguide formed by three parallel metal strips, the three parallel metal strips having a center strip connected to a positive terminal of a corresponding transceiver channel and two outer strips each connected to a negative terminal of the corresponding transceiver channel, the coplanar waveguide being configured to terminate at a transition within a region of an outer surface of a chip package, the chip package being configured to support at least one transmitter and / or at least one receiver, the region being covered by an end of the air waveguide and surrounded by a solder ball fence, the solder ball fence being configured to provide electromagnetic shielding for the air waveguide, the solder ball fence defining a gap through which the coplanar waveguide passes, the coplanar waveguide being arranged to make a 90 degree bend before passing through the gap and entering the region, the 90 degree bend in the coplanar waveguide facilitating conversion of the electromagnetic signal from the coplanar waveguide to the air waveguide by aligning the polarization of the coplanar waveguide with the air waveguide.

7. The transceiver according to claim 6, characterized in that: The transition portion comprises a monopole transition portion formed by extending the coplanar waveguide into the region covered by the end of the air waveguide; and The end of the waveguide covering the zone is open.

8. The transceiver according to claim 7, characterized in that: The central strip includes a length extending into the region covered by the air waveguide; and The length is equal to one quarter wavelength of a radar signal transmitted by the at least one transmitter or received by the at least one receiver.

9. The transceiver according to claim 8, characterized in that The monopolar transition portion is formed of at least one of copper, aluminum, silver, gold, or a metal alloy.

10. The transceiver according to claim 8, characterized in that The two outer strips are configured to form a ground plane.

11. The transceiver according to claim 6, wherein: the transition portion comprises a loop transition portion formed by a continuous rectangular metal loop connecting the two outer strips of the coplanar waveguide and bifurcating from the outer strips of the coplanar waveguide to create two loops having equal circumference; The end of the waveguide covering the zone is open.

12. The transceiver according to claim 11, wherein: The circumference of each of the two loops is half the wavelength of the radar signal transmitted by the at least one transmitter or received by the at least one receiver.

13. The transceiver according to claim 12, characterized in that The loop transition portion is formed of at least one of copper, aluminum, silver, gold, or a metal alloy.

14. The transceiver according to claim 6, wherein: The transition portion comprises a patch transition portion, the patch transition portion comprising a metal pad in contact with the center strip of the coplanar waveguide; and The two outer strips form a ground plane.

15. The transceiver according to claim 14, wherein: The patch transition portion has a length that is half the wavelength of a radar signal transmitted by the at least one transmitter or received by the at least one receiver.

16. The transceiver according to claim 15, characterized in that The patch transition portion is formed of at least one of copper, aluminum, silver, gold, or a metal alloy.

17. The transceiver according to claim 15, characterized in that The two outer strips are configured to form a ground plane.

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