RF module

Abstract

The invention relates to an RF module. The first device is on the second side of the PCB, electrically connected to the first signal line. The second device is on the second side of the PCB, electrically connected to the second signal line. The RF module includes a first RF port associated with the first device, the first device including an LO that generates an LO signal, and the circuit board includes a first opening between the first RF port and a first waveguide port associated with the first hollow waveguide, the first opening passing the LO signal from the first RF port into the first hollow waveguide. The RF module includes a second RF port associated with the second device, and the circuit board includes a second opening between the second RF port and a second waveguide port associated with the first waveguide, the second opening receiving an LO signal from the first hollow waveguide. The second device processes the first RF signal based on the received LO signal. The RF module includes a third RF port associated with the second device, and the circuit board includes a third opening that passes the first RF signal between the third RF port and a third waveguide port associated with the second hollow waveguide.

Description

Technical Field

[0001] The present disclosure relates to an RF module having a plurality of semiconductor circuit devices. Background Art

[0002] RF systems using semiconductor circuit devices are used in many millimeter wave applications, such as FMCW radar or 5G mobile communications. A monolithic microwave integrated circuit (MMIC) is a semiconductor circuit device that generally includes an RF circuit device for implementing multiple transmission (TX) channels and / or reception (RX) channels. In addition, in order to allow MIMO operation or phased antenna array operation, it is desirable to increase the number of transmission (TX) channels or reception (RX) channels so as to transmit and / or receive signals on an increased number of antennas. In order to implement an antenna array with multiple antennas, an implementation utilizes arranging the antenna on a printed circuit board. However, for such a solution, the manufacturing cost increases because the antenna array on the printed circuit board requires one or more specific layers to reduce the RF loss of the RF transmission signal in the microwave region above 20 GHZ. In addition, it is known that an implementation in which an antenna is provided in each package of a semiconductor circuit device or directly on each semiconductor chip. However, a specific package may be required, thereby increasing the cost, and space limitations may limit the number of antennas, which may increase the number of MMICs required for a specific number of antennas. Therefore, it is desirable to provide an RF module that allows high-performance antenna array operation at a reduced manufacturing cost. Summary of the invention

[0003] According to one example, an RF module includes a circuit board and a waveguide antenna, the circuit board includes a plurality of signal lines, the waveguide antenna is arranged on a first side of the circuit board, the waveguide antenna includes a body, an antenna element formed in the body, a first hollow waveguide formed in the body, and a second hollow waveguide formed in the body, wherein the second hollow waveguide is coupled to the antenna element.

[0004] The first semiconductor circuit device is disposed on the second side of the printed circuit board and electrically connected to a first signal line of the plurality of signal lines. The second semiconductor circuit device is disposed on the second side of the printed circuit board and electrically connected to a second signal line of the plurality of signal lines.

[0005] The RF module includes a first RF port associated with a first semiconductor circuit device, wherein the first semiconductor circuit device includes a local oscillator for generating a local oscillator signal, wherein the circuit board includes a first opening between the first RF port and a first waveguide port associated with the first hollow waveguide, the first opening being used to pass the local oscillator signal from the first RF port to the first hollow waveguide.

[0006] The RF module includes a second RF port associated with the second semiconductor circuit device, and the circuit board includes a second opening between the second RF port and a second waveguide port associated with the first waveguide, the second opening being used to receive a local oscillator signal from the first hollow waveguide. The second semiconductor circuit device is configured to process the first RF signal based on the received local oscillator signal.

[0007] The RF module includes a third RF port associated with the second semiconductor circuit device, and wherein the circuit board includes a third opening for passing the first RF signal between the third RF port and a third waveguide port associated with the second hollow waveguide.

[0008] Those skilled in the art will recognize additional features and advantages upon reading the following detailed description, and upon viewing the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present disclosure is illustrated in the figures of the accompanying drawings by way of example and not limitation, in which like reference numerals refer to similar or identical elements. The elements in the accompanying drawings are not necessarily drawn to scale relative to each other. The features of the various examples shown may be combined unless they exclude each other.

[0010] Figure 1A and Figure 1B An example of an RF module is shown;

[0011] Figure 2A and Figure 2B Another example of an RF module is illustrated;

[0012] Figure 3A and Figure 3B Another example of an RF module is illustrated;

[0013] Figure 4 An example of an RF port is illustrated;

[0014] FIG. 5A to FIG. 5G Another example of an RF port is illustrated;

[0015] Fig. 6A An example of a waveguide splitter is illustrated;

[0016] Figure 6B An example of a transmission adaptation element is illustrated; and

[0017] Fig. 7A , Figure 7B and Figure 7C An example of LO allocation is illustrated. DETAILED DESCRIPTION

[0018] The examples described herein provide a new concept for an RF module utilizing a waveguide antenna. In addition to providing a hollow waveguide within the waveguide antenna for transferring an RF signal from an RF port of an MMIC to an antenna radiating structure, the waveguide antenna also provides a hollow waveguide for transferring a local oscillator (LO) signal generated at one semiconductor circuit device to another semiconductor circuit device for synchronization.

[0019] Therefore, a compact, cost-effective and high-performance RF module is provided using the proposed concept. Compared with existing RF modules, waveguide antennas can be manufactured at a reduced cost using plastic materials and molding processes. In addition, waveguide antennas allow semiconductor circuit device synchronization by utilizing a local oscillator signal distributed from one semiconductor circuit device to another semiconductor circuit device via a hollow waveguide. Similar hollow waveguide shapes can be used for the distribution of LO signals and the transmission or reception of signals, which makes the design of additional LO distribution waveguides easy. Compared with existing solutions that require local oscillator signals to be distributed via signal lines on a printed circuit board (PCB), since the LO signal is in the same frequency range as the transmission and reception signals, the new concept is able to distribute the local oscillator signal without down-conversion and up-conversion. This makes it very attractive for applications that require processing RF signals in the microwave region above 60GHz. Existing solutions require a specific layer on the printed circuit board that is suitable for low-loss transmission at such high frequencies, or down-convert the local oscillator signal before the LO signal is transmitted, and then up-convert after receiving the LO signal at another semiconductor circuit device. Different from this, the new concept uses the waveguide structure within the waveguide antenna to achieve local oscillator signal distribution also in the high-frequency microwave region above 60GHz without the need for down-conversion and up-conversion. Therefore, no additional components such as high-frequency layers are required.

[0020] Reference now Figure 1A, describes a first example of an RF module 100. The RF module 100 includes a printed circuit board 12, a first semiconductor circuit device 2-1, and a second semiconductor circuit device 2-2. The first semiconductor circuit device 2-1 includes a first semiconductor chip 4-1, and the second semiconductor circuit device 2-2 includes a second semiconductor chip 4-2. The first semiconductor circuit device 2-1 includes a package formed by a molding portion 6-1 and a redistribution layer 8-1. The second semiconductor circuit device 2-2 includes a package formed by a molding portion 6-2 and a redistribution layer 8-2. The molding portions 6-1 and 6-2 can be formed by a molding process using a molding material. The molding portions 6-1 and 6-2 extend to the lateral direction of the first semiconductor chip 4-1 and the second semiconductor chip 4-2, respectively, to form a corresponding fan-out area. The redistribution layers 8-1 and 8-2 can each include one or more metal layers and one or more insulating layers to route signals transmitted to or from the corresponding semiconductor chip. The redistribution layers 8-1 and 8-2 can be formed by laminating the layers. The corresponding molding portion and the redistribution layer may form a fan-out wafer level package, such as an embedded wafer level ball grid array (eWLB).

[0021] The first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 are mounted on a first side of the printed circuit board 12 and are electrically and mechanically connected to the printed circuit board 12 via external contacts 14. The external contacts 14 may be solder balls, copper pillars, or any other structure that can be used to mount semiconductor circuit devices on a printed circuit board. Figure 1A Only two semiconductor circuit devices are shown in FIG. 1 , but it should be noted that more than two semiconductor circuit devices may be mounted on the printed circuit board 12 depending on the desired application.

[0022] The printed circuit board 12 includes a plurality of signal lines, which may include power signal lines that couple the first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 to a power device, respectively. The printed circuit board 12 may also include data signal lines that couple the first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 to a processor device mounted on the printed circuit board 12. The printed circuit board 12 may also include an isolation material, such as FR4 material.

[0023] The first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 may be monolithic microwave integrated circuit (MMIC) devices. The first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 may each include a circuit device for processing an RF signal. More specifically, the first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 may each include a plurality of transmission (TX) channels and a plurality of reception (RX) channels. Each of the first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 may include an RF circuit device, such as a phase shifter, a power amplifier, an RF coupler, an RF mixer, and a digital processing circuit device, such as a digital processor, a digital filter, a digital Fourier transform circuit device, or a Goertzel filter. At least the first semiconductor circuit device 2-1 may also include an RF signal generating circuit device, such as a local oscillator, for generating a local oscillator (LO) signal. In one example, the first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 may be FMCW radar MMIC devices operating in a frequency range above 20 GHz (e.g., in an ISM band, an ultra-wideband (UWB) band, an automotive long-range radar (LRR) band, or an automotive short-range radar (SRR) band). In such an implementation, the local oscillator of the first semiconductor circuit device 2-1 may generate a frequency-modulated RF signal including a plurality of chirps (also referred to as frequency ramps). According to the examples described herein, the first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 may form a cascade system or may be part of a cascade system. The first semiconductor circuit device 2-1 may be considered a master device in the cascade system because the device generates an LO signal, and the second semiconductor circuit device 2-2 may be considered a slave device because the second semiconductor circuit device 2-2 receives the LO signal from the first semiconductor circuit device 2-1 and utilizes the LO signal to process the RF signal, such as generating an RF transmission signal or demodulating a received RF signal. The transmission of the LO signal from the first semiconductor circuit device 2-1 to the second semiconductor circuit device 2-2 allows synchronization of RF processing. It should be noted that MIMO operation may require a predetermined phase relationship of the transmitted or received RF signals. When RF signals are processed in multiple semiconductor circuit devices, the concept of generating an LO signal in one semiconductor circuit device and transmitting the signal to other semiconductor circuit devices for RF processing can establish the required phase relationship.

[0024] The RF module 100 also includes a waveguide antenna 15, which includes a body 16 and a hollow waveguide formed in a cavity inside the body 16. The waveguide antenna 15 is mounted to the printed circuit board 12 at a first side of the body 16 so that the printed circuit board is located between the waveguide antenna 15 and the semiconductor circuit devices 2-1 and 2-2. The waveguide antenna 15 includes a plurality of antennas for providing an antenna array to be described later. The body 16 of the waveguide antenna 15 may include a plastic material and may be formed using molding technology or other manufacturing methods. The hollow waveguide is formed by a metal surface 17 of the cavity inside the body 16. The body 16 may be a single component or may be formed by mounting two or more components of the body 16 together. The mounting of the components may include threaded connection, gluing, welding or other mounting methods. The waveguide antenna 15 also includes a receiving and / or transmitting antenna formed by an antenna element 18. The antenna element 18 may be configured to transmit RF signals to the outside of the RF module or to receive RF signals from the outside. Each of the antenna elements 18 may include one or more slots formed at the second side of the body 16, so that a slotted antenna is formed by the antenna elements 18. The antenna elements 18 may form an antenna array for providing MIMO operation of the RF module 100, so that RF signals are transmitted to the outside of the RF module 100 by multiple antennas and RF signals are received from the outside of the RF module 100 by multiple antennas. Each of the antennas is associated with one or more corresponding RF channels in one of the first semiconductor circuit device 2-1 or the second semiconductor circuit device 2-2. In some examples, an antenna may be associated with one RF channel, while in other examples, one antenna may be associated with multiple RF channels.

[0025] The waveguide antenna 15 includes a first hollow waveguide 20-1 for transferring the LO signal from the first semiconductor circuit device 2-1 to the second semiconductor circuit device 2-2. Since the LO signal distribution is provided for synchronizing the RF processing in the first semiconductor circuit device 2-1 with the second semiconductor circuit device 2-2, the first hollow waveguide 20-1 may also be called a synchronization waveguide.

[0026] The RF module 100 has a first waveguide port 22-1 associated with the first hollow waveguide 20-1 and a second waveguide port 22-2 associated with the first hollow waveguide. The first waveguide port 22-1 and the second waveguide port 22-2 are arranged in the waveguide antenna 15, and in one example can be the first end and the second end of the hollow waveguide or can be coupled to the first end and the second end of the first hollow waveguide 20-1.

[0027] A first opening 24-1 is formed in the printed circuit board 12 such that the first opening 24-1 is located between a first RF port 10-1 and a first waveguide port 22-1 associated with the first semiconductor circuit device 2-1. The first RF port 10-1, the first opening 24-1, and the first waveguide port 22-1 are configured to allow an LO signal to be coupled from the first semiconductor circuit device 2-1 into the first hollow waveguide 20-1. A second opening 24-2 is formed in the printed circuit board 12 such that the second opening 24-2 is located between a second RF port 10-2 and a second waveguide port 22-2 associated with the second semiconductor circuit device 2-2. A metal wall 13 may be formed on a side wall of the printed circuit board 12 associated with the openings 24-1 and 24-2. The second RF port 10-2, the second opening 24-2, and the second waveguide port 22-2 are configured to allow an LO signal to be coupled from the first hollow waveguide 20-1 into the second semiconductor circuit device 2-2. As Figure 1A As shown, the RF ports 10-1 and 10-2 extend in the fan-out regions of the first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2, respectively. Figure 1A As shown, the first hollow waveguide 20 - 1 may have a vertical portion extending perpendicular to the major surface of the body 16 and one or more lateral portions extending parallel to the major surface of the body 16 .

[0028] As described above, the second semiconductor circuit device 2-2 processes the first RF signal using the LO signal received from the first semiconductor circuit device 2-1. More specifically, the LO signal is used to generate an RF transmission signal, or to generate a baseband signal by supplying the LO signal to a mixer and mixing the LO signal with the received RF signal.

[0029] The RF module 100 includes a third RF port 10-3 associated with the second semiconductor circuit device 2-2, and the printed circuit board 12 includes a third opening 24-3 for transmitting a first RF signal between the third RF port 10-3 and a third waveguide port 22-3 associated with the second hollow waveguide 20-2. The second hollow waveguide 20-2 is formed in the body 16 and couples the third waveguide port 22-3 to the corresponding antenna element 18. In the case where the third RF port 10-3 is a receiving RF port, the first RF signal is received from the corresponding antenna element 18 via the second hollow waveguide 20-2 and the third waveguide port 22-3. In the case where the first RF port 10-3 is a transmitting RF port, the first RF signal is transmitted from the third RF port 10-30 to the corresponding antenna element 18 via the third waveguide port 22-3 and the second hollow waveguide 20-2.

[0030] The first hollow waveguide 20-1 and the second hollow waveguide 20-2 may be rectangular waveguides having a rectangular cross-section, or may be circular or elliptical waveguides having a circular or elliptical cross-section. The first hollow waveguide 10-1 and the second hollow waveguide 10-2 may be configured to transmit in a TE mode or a TM mode. In an example, the first hollow waveguide 10-1 and the second hollow waveguide 10-2 may have the same cross-sectional shape and the same cross-sectional area, because the signals transmitted in the first hollow waveguide 10-1 and the second hollow waveguide 10-2 may have the same frequency or within the same frequency range. This allows LO distribution to be implemented in a waveguide antenna without any specific design changes to the hollow waveguide provided in the body 16.

[0031] It should also be noted that the first semiconductor circuit device 2 - 1 and the second semiconductor circuit device 2 - 2 may have additional RF ports coupled to the respective antenna elements 18 in the same manner as described above. Figure 1B An example is schematically shown in which each of the first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 has 3 transmission channels and 4 reception channels, which are coupled to the corresponding antenna elements via the hollow waveguide as described above. Figure 1B The RF system implements a MIMO system with 6 transmission channels and 8 reception channels, wherein each of the transmission channels and the reception channels is based on an LO signal generated in the first semiconductor circuit device 2-1. FIG1 shows the distribution of the LO signal from the first semiconductor circuit device 2-1 to the second semiconductor circuit device 2-2 via the first hollow waveguide 20-1, and the transfer of the transmission and reception signals via the corresponding second hollow waveguides.

[0032] Reference now Figure 2A and Figure 2B , another example of the RF module 200 will be described. Figure 1A and Figure 1BUnlike the described example, the RF module 200 includes LO signal self-feeding back to the first semiconductor circuit device 2-1. To this end, the first hollow waveguide 20-1 is branched into a first portion and a second portion. As described above, the first portion is coupled to the second waveguide port 22-2 to pass the LO signal to the RF port 10-2 via the second waveguide port 22-2 and the second opening 24-2. The second portion is coupled to the fourth waveguide port 22-4 associated with the first semiconductor circuit device 2-1. The fourth opening 24-4 is provided in the printed circuit board 12 so as to pass the LO signal transmitted in the second portion of the first hollow waveguide 20-1 to the RF port associated with the first semiconductor circuit device 2-1. In the first semiconductor circuit device 2-1, the LO signal received from the second portion of the first hollow waveguide 20-1 is then passed to the first semiconductor chip 4-1. Instead of directly using the LO signal generated in the first semiconductor chip 4-1, the first semiconductor chip 4-1 uses the LO signal fed back via the second portion of the first hollow waveguide 20-1 to process the RF signal, such as generating a transmission signal or down-converting a reception signal. Feedback of the LO signal allows synchronization of the reception and transmission channels in the semiconductor circuit devices 2-1 and 2-2 to be obtained in a more stable manner. Temperature changes cause the length of the hollow waveguide to change, and the temperature of the hollow waveguide is relatively stable. Figure 1A and Figure 1B In the example of , this may cause the relative phase of the LO signals used in the first semiconductor circuit device 2-1 and the second semiconductor circuit device 2-2 to change. Figure 2A In some examples, the LO signal delivered to the second semiconductor circuit device 2-2 and the LO signal delivered to the first semiconductor circuit device 2-1 are affected in the same manner and thus the relative phases are compensated or reduced. In some examples, in the first hollow waveguide 20-1, the length from the first waveguide port 22-1 to the second waveguide port 22-2 is the same as the length from the first waveguide port 22-1 to the fourth waveguide port 22-4, so that the distribution of the LO signal to the two waveguide ports is symmetrical. Other features of the RF module 200 are similar to the RF module 100, and reference is made to Figure 1A Description.

[0033] Figure 2B Schematically shows an RF module 200 implementing LO feedback. Figure 1B Compared to the RF module 100 shown, the RF module 200 has one less receiving channel because the corresponding RF port is now used to receive the LO signal that is fed back to the first semiconductor circuit device 2-1. However, in other embodiments, a dedicated LO signal port can be used to transmit and receive the LO signal, wherein the feedback of the LO signal may not reduce the number of RF channels.

[0034] Reference now Figure 2A and Figure 2B , another example of the RF module 300 will be described.

[0035] Instead of generating the LO signal in an MMIC including an RF channel, the first semiconductor circuit device 2-1 is implemented as a dedicated LO generating device in the RF module 300. The LO signal generated in the first semiconductor circuit device 2-1 is then transferred to the second waveguide port 22-2 via the first portion of the first hollow waveguide 20-1, and is transmitted to the second RF port 10-2 associated with the second semiconductor circuit device 2-2 via the second opening 24-2. In addition, the LO signal generated in the first semiconductor circuit device 2-1 is transferred to the fourth waveguide port 22-4 via the second portion of the first hollow waveguide 20-1, and is transmitted to the fourth RF port 10-2 associated with the third semiconductor circuit device 2-3 via the fourth opening 24-4. The second semiconductor circuit device 2-2 and the third semiconductor circuit device 2-3 are implemented as MMICs having an RF channel (e.g., an RF receiving channel or an RF transmitting channel). As described above, the LO signal is used to process the RF signal in the second semiconductor circuit device 2-2 and the third semiconductor circuit device 2-3. In some examples, in the first hollow waveguide 20-1, the length from the first waveguide port 22-1 to the second waveguide port 22-2 is the same as the length from the first waveguide port 22-1 to the fourth waveguide port 22-4, so that the distribution of the LO signal to the two waveguide ports is symmetrical. Other features of the RF module 200 are similar to the RF module 100 and the RF module 300, and refer to Figure 1A and Figure 1B Description.

[0036] Figure 3B The LO distribution of the RF module 300 is schematically shown, in which the first semiconductor circuit device 2 - 1 symmetrically distributes the LO signal to the second semiconductor circuit device 2 - 2 and the third semiconductor circuit device 2 - 3 via the first hollow waveguide 20 - 1 .

[0037] Reference now Figure 4, an example of the RF port 10 will be described. The RF port 10 includes a substrate integrated waveguide 42 configured to pass an RF signal from a semiconductor chip 4 to an opening 24 of a printed circuit board 12. The substrate integrated waveguide tube 42 can use a transmitter integrated into the redistribution layer 8 of the relevant semiconductor circuit device to provide coupling from the substrate integrated waveguide 42 to the corresponding waveguide port via the opening 24 of the printed circuit board 12. In other examples, the transmitter can be integrated into the printed circuit board 12 or arranged on the printed circuit board 12 to provide coupling to the corresponding waveguide port. In some examples, the transmitter can be configured to receive an RF signal having a substantially lateral transmission direction from the semiconductor chip 4, and can be configured to pass the same RF signal as an RF signal having a substantially vertical transmission direction, so as to efficiently transmit the RF signal to the vertical portion of the hollow waveguide. A similar RF port can be provided to implement an RF port that is configured to receive a signal from a corresponding hollow waveguide. The same RF port can be used to pass an LO signal and to pass an RF transmission or reception signal because both use the same frequency or can be within the same frequency range.

[0038] Another example of RF port 10 is FIG. 5A to FIG. 5G shown. Figure 5A A side view of a portion of a redistribution layer of a semiconductor circuit device (e.g., a first semiconductor circuit device 2-1 or a second semiconductor circuit device 2-2) is shown. The first layer 502 is the layer closest to the chip level in the vertical direction. The first layer 502 includes a signal line and a ground line connected to the third layer 504 through a via arranged in the second layer 503. The signal line and the ground line can form a planar waveguide to transmit RF signals. The third layer 504 forms the top of the substrate integrated waveguide and is connected to the fifth layer 506 through a via arranged in the fourth layer 505. The fifth layer 506 forms the lower part of the substrate integrated waveguide.

[0039] Figure 5B A top view of the first layer 502 is shown. In the first layer 502, a signal line 502-1 is formed, which extends above and passes through an area 504-1 associated with a gap (opening) in the third layer 504, which will be explained later. The signal line 502-1 is connected to a signal line of the semiconductor chip 4 at one end. The first layer 502 also includes a ground line 502-2 connected to a ground potential. It can be seen that the ground line 502-2 does not extend in the area 504-1 and does not cross the area 504-1. The signal line 502-1 and the ground line 502-2 are metal lines and form an RF planar waveguide. In order to couple the RF signal into the substrate integrated waveguide, the signal line 502-1 is electrically connected to the via 503-1 and the ground line 502-2 is electrically connected to a corresponding via among a plurality of vias 503-2, as shown in FIG. Figure 5CVias 503-1 and 503-2 provide electrical connections from the first layer 502 to the third layer 504 in the vertical direction to stimulate current in the third layer 504, thereby allowing RF coupling into the substrate integrated waveguide.

[0040] Figure 5D The third layer 504 is shown, which is formed as a continuous metal layer with a gap in the region 504-1. Since the signal line 502-1 crosses the region 504-1, and the ground line 502-2 does not cross the region 504-1, the AC current flowing around the gap region 504-1 is excited in the third layer 504. Since the third layer 504 is the top plate of the substrate integrated waveguide, the AC current excites the RF signal in the substrate integrated waveguide. Figure 5D In the figure, the opening is shown as a rectangular U-shaped slot, but other shapes (such as a straight slot, a V-shaped slot or a semicircular slot) are also possible. Compared with a straight slot, a U-shaped, V-shaped or semicircular slot reduces the size in the lateral direction, increases design flexibility, and allows more RF ports to be implemented in a specific area.

[0041] The third layer 504 is connected to a fifth layer 506 , which serves as the bottom plate of the substrate integrated waveguide, through a via 505 - 1 arranged in layer 505 . Figure 5E A via 505 - 1 is shown defining the lateral boundaries of the substrate integrated waveguide. Fig. 5F The fifth layer 506 is shown as a continuous metal layer having an opening 506 - 1 to define an emitter 506 - 2 .

[0042] The transmitter 506-2 provides vertical RF coupling to a corresponding opening in the printed circuit board 12 and a corresponding waveguide port to stimulate RF signal transmission in the hollow waveguide below the transmitter.

[0043] Figure 5G A transparent top view of the structures in layers 502 to 506 forming the RF port as described above is shown. In the case where the RF port is a transmission RF port, the substrate integrated waveguide is formed with a structure for coupling the RF signal from the planar waveguide into the substrate integrated waveguide, and is formed with a transmitter for coupling the RF signal from the substrate integrated waveguide into the opening of the printed circuit board 12. In the case where the RF port is a reception RF port, the substrate integrated waveguide is formed with a transmitter for coupling the RF signal from the opening of the printed circuit board 12 into the substrate integrated waveguide, and is formed with a structure for coupling the RF signal from the substrate integrated waveguide into the planar waveguide.

[0044] Reference now Fig. 6A and Figure 6B , the functional structure provided in the hollow waveguide of the waveguide antenna will be described.

[0045] Fig. 6A A splitter element 600 is shown as a functional element that can be implemented in the waveguide 20. The splitter element 600 includes a first splitter port 20-A, a second splitter port 20-B, and a third splitter port 20-C. The first splitter port 20A is a receiving port configured to receive an RF signal from a first portion of the waveguide 20. The splitter 600 is configured to split the RF signal into a first RF signal portion and a second RF signal portion, which are transmitted to corresponding waveguide portions of the waveguide 20 via the second splitter port 20-B and the third splitter port 20-C. The splitting can be symmetrical so that the first RF signal portion and the second RF signal portion have the same amount of power. For example, the above splitter can be used in Figure 2A and Figure 2B In the example of , the splitter can be used to achieve LO distribution by self-feeding. In addition, the splitter can be used for the following Fig. 7A and Figure 7B Described in the example.

[0046] Figure 6B An adapter element 602 is shown as another functional element that can be implemented in the hollow waveguide 20. The adapter element 602 includes a portion 20-D in which, for example, the waveguide form or the waveguide cross-sectional area is changed to modify the RF signal output or received via the port 20-E. The adapter element 602 can be used, for example, at the waveguide ports 22-1, 22-2, 22-3, 22-4 described in the above examples to couple the RF signal into the openings 24-1, 24-2, 24-3, 24-4, or to receive the RF signal from the openings 24-1, 24-2, 24-3, 24-4. This can increase the coupling efficiency and can reduce the loss of the RF signal.

[0047] Reference now FIG. 7A to FIG. 7C , describes an example of LO signal distribution implemented in an RF module (e.g., RF modules 100, 200, and 300). Fig. 7AAn example of symmetrical LO signal distribution from a first semiconductor circuit device 2-1 to semiconductor circuit devices 2-2, 2-3, 2-4, and 2-5 is shown. The first hollow waveguide 20-1 is split into two hollow waveguide sections using a first splitter 600-1. Each of the hollow waveguide sections is further split using splitters 600-2 and 600-3. The first hollow waveguide couples the RF port of the first semiconductor circuit device 2-1 that distributes the LO signal with the corresponding RF ports of the semiconductor circuit devices 2-2, 2-3, 2-4, and 2-5 that receive the LO signal. The length of the waveguide section between the first semiconductor circuit device 2-1 and each of the semiconductor circuit devices 2-2, 2-3, 2-4, and 2-5 is the same, so that the LO signal is symmetrically distributed, and the phase of the LO signal received at the semiconductor circuit devices 2-2, 2-3, 2-4, and 2-5 is the same.

[0048] Figure 7B An example of LO signal distribution from a first semiconductor circuit device 2-1 to semiconductor circuit devices 2-2, 2-3, and 2-4 with self-feeding is shown. The first hollow waveguide 20-1 is split into two hollow waveguide portions using a first splitter 600-1. Each of the hollow waveguide portions is further split into additional hollow waveguide portions using splitters 600-2 and 600-3. One of the additional hollow waveguide portions coupled to splitter 600-2 is coupled to the RF port of the second semiconductor circuit device 2-2, and one of the additional hollow waveguide portions coupled to splitter 600-2 is coupled back to the input RF port of the first semiconductor circuit device 2-1. In operation, the first semiconductor circuit device 2-1 uses the fed-back LO signal for processing, such as generating a transmission signal or mixing a received signal. In addition, the additional hollow waveguide portions coupled to splitter 600-3 are coupled to the RF ports of semiconductor circuit devices 2-3 and 2-4, respectively. The length of the waveguide portion between the first semiconductor circuit device 2-1 and the input RF port of the first semiconductor circuit device 2-1 is the same as the length of the waveguide portion between the first semiconductor circuit device 2-1 and each of the semiconductor circuit devices 2-2, 2-3, and 2-4, so that the LO signal is symmetrically distributed and the phases of the LO signals received at the semiconductor circuit devices 2-1, 2-2, 2-3, and 2-4 are the same. The LO distribution to the plurality of semiconductor circuit devices 2-2, 2-3, and 2-4 including feedback to the first semiconductor circuit device 2-1 allows the stability of the phase of the LO signal processed by the semiconductor circuit devices 2-1, 2-2, 2-3, and 2-4 to be obtained, thereby allowing the semiconductor circuit devices 2-1, 2-2, 2-3, 2-4 to be used in a MIMO operation for transmitting and receiving signals.

[0049] Another example of LO signal distribution is Figure 7C shown. Figure 7CLO distribution for a daisy chain configuration is shown. The RF port of the first semiconductor circuit device 2-1 is coupled to the first portion of the first hollow waveguide 20-1 to couple the LO signal into the first hollow waveguide 20-1. The LO signal is received at the input RF port of the second semiconductor circuit device 2-2 and is passed to the second portion of the first hollow waveguide 20-1. The LO signal is received at the input RF port of the third semiconductor circuit device 2-3 and is passed to the third portion of the first hollow waveguide 20-1. At the input RF port of the fourth semiconductor circuit device 2-4, the LO signal is received from the third portion of the first hollow waveguide 20-1. In this example, the LO signals received at the semiconductor circuit devices 2-2, 2-3, and 2-4 have different phases, and the phase difference may vary with temperature. In order to establish MIMO operation, compensation or calibration techniques may be applied to account for phase changes caused by temperature changes.

[0050] In the above, various examples of RF modules utilizing a waveguide antenna having a hollow waveguide formed inside the body of the waveguide antenna have been described. The hollow waveguide is used to transmit transmission signals and reception signals between the antenna element of the waveguide antenna and a plurality of semiconductor circuit devices, and to distribute LO signals among the plurality of semiconductor circuit devices. This allows for simple and cost-effective implementation of an RF module, such as for MIMO operation, avoiding routing LO signals on a printed circuit board.

[0051] In addition to the above examples, the following examples are also disclosed herein.

[0052] Example 1 is an RF module, including:

[0053] A circuit board including a plurality of signal lines,

[0054] a waveguide antenna disposed on a first side of the circuit board, the waveguide antenna comprising a body, an antenna element formed in the body, a first hollow waveguide formed in the body, and a second hollow waveguide formed in the body, wherein the second hollow waveguide is coupled to the antenna element,

[0055] a first semiconductor circuit device disposed on the second side of the printed circuit board and electrically connected to a first signal line among the plurality of signal lines,

[0056] a second semiconductor circuit device disposed on the second side of the printed circuit board and electrically connected to a second signal line among the plurality of signal lines,

[0057] wherein the RF module includes a first RF port associated with the first semiconductor circuit device, wherein the first semiconductor circuit device includes a local oscillator for generating a local oscillator signal, wherein the circuit board includes a first opening between the first RF port and a first waveguide port associated with the first hollow waveguide, the first opening being used to pass the local oscillator signal from the first RF port into the first hollow waveguide,

[0058] wherein the RF module includes a second RF port associated with the second semiconductor circuit device, wherein the circuit board includes a second opening between the second RF port and a second waveguide port associated with the first waveguide, the second opening being configured to receive the local oscillator signal from the first hollow waveguide, wherein the second semiconductor circuit device is configured to process the first RF signal based on the received local oscillator signal,

[0059] wherein the RF module includes a third RF port associated with the second semiconductor circuit device, and wherein the circuit board includes a third opening for passing the first RF signal between the third RF port and a third waveguide port associated with the second hollow waveguide.

[0060] Example 2 is an RF module according to Example 1, wherein the first RF signal is an RF transmission signal, and wherein the second semiconductor circuit device is configured to generate the RF transmission signal based on the received local oscillator signal, wherein the third RF port includes a transmitter, and the transmitter is used to pass the RF transmission signal via the third opening to the first waveguide port for transmission via the antenna element.

[0061] Example 3 is an RF module according to Example 1, wherein the first RF signal is an RF receive signal received by the antenna element, and wherein the third RF port includes a transmitter for receiving the RF receive signal from the second hollow waveguide via the third opening, and wherein the second semiconductor circuit device is configured to down-convert the RF receive signal using the received local oscillator signal.

[0062] Example 4 is the RF module of Examples 2 and 3, wherein the transmitter is integrated into the second semiconductor circuit device.

[0063] Example 5 is an RF module according to any of the preceding examples, wherein the first semiconductor circuit device and the second semiconductor circuit device include a redistribution layer molding material that defines a fan-out region, and wherein at least one of the second RF port or the third RF port is arranged in the fan-out region.

[0064] Example 6 is an RF module according to any of the preceding examples, wherein the RF module includes a fourth RF port associated with the first semiconductor circuit device, and wherein the circuit board includes a fourth opening between the fourth RF port and a fourth waveguide port associated with the first hollow waveguide, wherein the first hollow waveguide includes a splitter for splitting the local oscillator signal into a first portion passed to the second RF port and a second portion passed to the fourth RF port.

[0065] Example 7 is an RF module according to any of the preceding examples, wherein the first semiconductor circuit device is a main monolithic microwave integrated device, and wherein the second semiconductor circuit device is an auxiliary monolithic microwave integrated circuit device, wherein the first monolithic microwave integrated circuit device includes a first plurality of RF channels, and wherein the auxiliary monolithic microwave integrated circuit device includes a second plurality of RF channels, wherein the auxiliary monolithic microwave integrated circuit device is configured to synchronize the second plurality of RF channels to the first plurality of RF channels using a received local oscillator signal.

[0066] Example 8 is an RF module according to any of the preceding examples, wherein the body includes body parts mounted together.

[0067] Example 9 is an RF module according to any of the preceding examples, wherein the body comprises a plastic material, and wherein the first hollow waveguide and the second hollow waveguide comprise a metal layer on a wall of an opening formed in the body.

[0068] Example 10 is an RF module according to any of the preceding examples, wherein the antenna element includes a plurality of slits formed on an outer surface of the body.

[0069] Example 11 is an RF module according to any of the preceding examples, wherein the RF module further includes at least one of a power supply arranged on the circuit board or a processing device arranged on the circuit board.

[0070] Example 12 is an RF module according to any of the preceding examples, wherein each of the first waveguide port, the second waveguide port, and the third waveguide port includes a transmission adaptation element for adapting transmission characteristics to couple with the first opening, the second opening, and the third opening, respectively.

[0071] Example 13 is the RF module of Example 12, wherein the transmission adaptation element includes a variable waveguide portion, the variable waveguide portion including at least one of the following:

[0072] Change the waveguide form, or

[0073] Varying waveguide cross section.

[0074] Example 14 is an RF module according to any of the preceding examples, wherein the first semiconductor circuit device and the second semiconductor circuit device are FMCW radar devices, and wherein the local oscillator signal includes a plurality of frequency modulated radar chirps.

[0075] Example 15 is an RF module according to any one of the preceding examples, wherein the first hollow waveguide includes a first portion extending perpendicular to the main surface of the circuit board and a second portion extending parallel to the main surface of the circuit board, and wherein the second hollow waveguide includes a third portion extending perpendicular to the main surface of the circuit board and a fourth portion extending parallel to the main surface of the circuit board.

[0076] Example 16 is the RF module of Example 15, wherein the second portion is closer to the circuit board than the fourth portion.

[0077] Example 17 is an RF module according to any one of the preceding examples, wherein the second semiconductor circuit device includes a semiconductor package, the semiconductor package includes a redistribution layer, wherein the third RF port includes a substrate integrated waveguide structure, the substrate integrated waveguide structure is formed by a first metal layer of the redistribution layer, a second metal layer of the redistribution layer, and a plurality of vertical metal structures formed between the first metal layer and the second metal layer.

[0078] Example 18 is the RF module of Example 17, wherein the redistribution layer includes a third metal layer, wherein the third metal extends over gaps in the second metal layer.

[0079] Example 19 is an RF module according to any of the preceding examples, wherein the RF module includes a transmitter associated with at least one of the first RF port, the second RF port, or the third RF port, wherein the transmitter is integrated in or arranged on the circuit board.

[0080] Although specific examples have been shown and described herein, it will be appreciated by those skilled in the art that the specific examples shown and described may be replaced with various alternatives and / or equivalent implementations without departing from the scope of the present invention. This application is intended to cover any adaptation or variation of the specific examples discussed herein. Therefore, the present invention is limited only by the claims and their equivalents.

[0081] It should be noted that the methods and devices (including the preferred embodiments thereof outlined in this document) may be used alone or in combination with other methods and devices disclosed in this document. Furthermore, features outlined in the context of a device also apply to the corresponding method and vice versa. Furthermore, all aspects of the methods and devices outlined in this document may be combined in any manner. In particular, the features of the claims may be combined with each other in any manner.

[0082] It should be noted that the description and drawings merely illustrate the principles of the proposed method and system. Those skilled in the art will be able to implement various arrangements that, although not explicitly described or shown herein, embody the principles of the present invention and are included in the spirit and scope of the present invention. In addition, all examples and embodiments summarized in this document are primarily and explicitly intended to be used for explanation purposes only to help the reader understand the principles of the proposed method and system. In addition, all statements of the principles, aspects and embodiments of the present invention and their specific examples provided herein are intended to include their equivalents.

Claims

1. An RF module, comprising: A circuit board including a plurality of signal lines, a waveguide antenna disposed on a first side of the circuit board, the waveguide antenna comprising a body, an antenna element formed in the body, a first hollow waveguide formed in the body, and a second hollow waveguide formed in the body, wherein the second hollow waveguide is coupled to the antenna element, a first semiconductor circuit device disposed on the second side of the circuit board and electrically connected to a first signal line among the plurality of signal lines, a second semiconductor circuit device disposed on the second side of the circuit board and electrically connected to a second signal line among the plurality of signal lines, wherein the RF module includes a first RF port associated with the first semiconductor circuit device, wherein the first semiconductor circuit device includes a local oscillator for generating a local oscillator signal, wherein the circuit board includes a first opening, the first opening being between the first RF port and a first waveguide port associated with the first hollow waveguide, the first opening being used to pass the local oscillator signal from the first RF port into the first hollow waveguide, wherein the RF module includes a second RF port associated with the second semiconductor circuit device, wherein the circuit board includes a second opening between the second RF port and a second waveguide port associated with the first waveguide, the second opening being configured to receive the local oscillator signal from the first hollow waveguide, wherein the second semiconductor circuit device is configured to process the first RF signal based on the received local oscillator signal, wherein the RF module comprises a third RF port associated with the second semiconductor circuit device, and wherein the circuit board comprises a third opening for passing the first RF signal between the third RF port and a third waveguide port associated with the second hollow waveguide.

2. The RF module of claim 1 , wherein the first RF signal is an RF transmission signal, and wherein the second semiconductor circuit device is configured to generate the RF transmission signal based on the received local oscillator signal, wherein the third RF port includes a transmitter for transmitting the RF transmission signal via the third opening to the first waveguide port for transmission via the antenna element.

3. The RF module of claim 1 , wherein the first RF signal is an RF receive signal received by the antenna element, and wherein the third RF port comprises a transmitter for receiving the RF receive signal from the second hollow waveguide via the third opening, and wherein the second semiconductor circuit device is configured to down-convert the RF receive signal using the received local oscillator signal.

4. The RF module according to claim 2 and 3, wherein the transmitter is integrated into the second semiconductor circuit device.

5. The RF module according to any one of the preceding claims, wherein the first semiconductor circuit device and the second semiconductor circuit device each include a redistribution layer and a molding material defining a corresponding fan-out area, and wherein at least one of the second RF port or the third RF port is arranged in the corresponding fan-out area.

6. The RF module of any of the preceding claims, wherein the RF module comprises a fourth RF port associated with the first semiconductor circuit device, and wherein the circuit board comprises a fourth opening between the fourth RF port and a fourth waveguide port associated with the first hollow waveguide, wherein the first hollow waveguide comprises a splitter for splitting the local oscillator signal into a first portion passed to the second RF port and a second portion passed to the fourth RF port.

7. An RF module according to any of the preceding claims, wherein the first semiconductor circuit device is a primary monolithic microwave integrated circuit device, and wherein the second semiconductor circuit device is an auxiliary monolithic microwave integrated circuit device, wherein the first monolithic microwave integrated circuit device includes a first plurality of RF channels, and wherein the auxiliary monolithic microwave integrated circuit device includes a second plurality of RF channels, wherein the auxiliary monolithic microwave integrated circuit device is configured to synchronize the second plurality of RF channels to the first plurality of RF channels using a received local oscillator signal.

8. An RF module according to any preceding claim, wherein the body comprises body parts which are mounted together.

9. The RF module of any one of the preceding claims, wherein the body comprises a plastic material, and wherein the first hollow waveguide and the second hollow waveguide comprise metal layers formed on walls of openings in the body.

10. An RF module according to any preceding claim, wherein the antenna element comprises a plurality of slots formed on an outer surface of the body.

11. The RF module of any one of the preceding claims, wherein the RF module further comprises at least one of a power supply disposed on the circuit board or a processing device disposed on the circuit board.

12. The RF module according to any one of the preceding claims, wherein each of the first waveguide port, the second waveguide port and the third waveguide port comprises a transmission adaptation element for adapting transmission characteristics to couple with the first opening, the second opening and the third opening, respectively.

13. The RF module of claim 12, wherein the transmission adaptation element comprises a variable waveguide portion, the variable waveguide portion comprising at least one of the following: Change the waveguide form, or Varying waveguide cross section.

14. The RF module of any one of the preceding claims, wherein the first semiconductor circuit device and the second semiconductor circuit device are FMCW radar devices, and wherein the local oscillator signal comprises a plurality of frequency modulated radar chirps.

15. An RF module according to any one of the preceding claims, wherein the first hollow waveguide includes a first portion extending perpendicular to the main surface of the circuit board and a second portion extending parallel to the main surface of the circuit board, and wherein the second hollow waveguide includes a third portion extending perpendicular to the main surface of the circuit board and a fourth portion extending parallel to the main surface of the circuit board. The RF module of claim 15 , wherein the second portion is closer to the circuit board than the fourth portion.

17. The RF module of any one of the preceding claims, wherein the second semiconductor circuit device comprises a semiconductor package, the semiconductor package comprising a redistribution layer, wherein the third RF port comprises a substrate integrated waveguide structure, the substrate integrated waveguide structure being formed by: a first metal layer of the redistribution layer, a second metal layer of the redistribution layer, and a plurality of vertical metal structures formed between the first metal layer and the second metal layer.

18. The RF module of claim 17, wherein the redistribution layer comprises a third metal layer, wherein the third metal extends over gaps in the second metal layer.

19. The RF module according to any of the preceding claims, wherein the RF module comprises a transmitter associated with at least one of the first RF port, the second RF port or the third RF port, wherein the transmitter is integrated in or arranged on the circuit board.

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