PATENT DOCUMENT

Publication Number: US-11581633-B2
Application Number: US-202017014814-A
Country: US
Kind Code: B2

Title: Electronic devices with passive radio-frequency power distribution circuitry

Abstract:
An electronic device may include a transceiver, first and second antennas, and a passive radio-frequency power distribution circuit. The distribution circuit may have a first port coupled to the transceiver, a second port coupled to the first antenna, and a third port coupled to the third antenna. The distribution circuit may include a transformer coupled between the ports. The transformer may have at least two intertwined inductors formed from conductive traces on a dielectric substrate. The intertwined inductors may be concentric about a common point. The intertwined inductors may extend from the common point to the second and third ports. The intertwined inductors may have a coil or spiral shape and may wind around the common point at least once. Intertwining the inductors may serve to minimize the lateral footprint of the distribution circuit in the device.

Claims:
What is claimed is: 
     
       1. An electronic device comprising:
 a dielectric substrate; and 
 a passive radio-frequency power distribution circuit having a first port, a second port, a third port, and a transformer that couples the first port to the second and third ports, the transformer having
 a first inductor coupled between the first and second ports, and 
 a second inductor coupled between the first and third ports, the second inductor being intertwined with the first inductor on the dielectric substrate. 
 
 
     
     
       2. The electronic device of  claim 1 , wherein the first inductor includes first conductive traces on the dielectric substrate, the second inductor includes second conductive traces on the dielectric substrate, the first and second conductive traces extend from opposing sides of a feed point, the first conductive traces extend from the feed point to the second port, and the second conductive traces extend from the feed point to the third port. 
     
     
       3. The electronic device of  claim 2 , wherein the first conductive traces wind at least once around the feed point and the second conductive traces wind at least once around the feed point. 
     
     
       4. The electronic device of  claim 3 , wherein the dielectric substrate has a first dielectric layer and a second dielectric layer stacked onto the first dielectric layer, the first and second conductive traces are patterned on the second dielectric layer, and the passive radio-frequency power distribution circuit has a feed trace on the first dielectric layer that is coupled to the first port. 
     
     
       5. The electronic device of  claim 4 , the passive radio-frequency power distribution circuit comprising:
 a conductive via that extends through the first dielectric layer to couple the feed trace to the feed point. 
 
     
     
       6. The electronic device of  claim 3 , further comprising:
 a first antenna coupled to the second port; 
 a second antenna coupled to the third port; and 
 a transceiver coupled to the first port and configured to convey radio-frequency signals using the first and second antennas. 
 
     
     
       7. The electronic device of  claim 6 , further comprising:
 a third antenna, wherein the transceiver is configured to convey radio-frequency signals using the third antenna, the passive radio-frequency power distribution circuit has a fourth port coupled to the third antenna, and the transformer couples the first port to the fourth port. 
 
     
     
       8. The electronic device of  claim 7 , the transformer comprising:
 a third inductor coupled between the first and fourth ports, wherein the third inductor is intertwined with the first and second inductors on the dielectric substrate, the third inductor includes third conductive traces on the dielectric substrate, the third conductive traces extend from the feed point to the third port, and the third conductive traces wind at least once around the feed point. 
 
     
     
       9. The electronic device of  claim 8 , the passive radio-frequency power distribution circuit comprising:
 a first capacitor coupled between the second and third ports; 
 a second capacitor coupled between the third and fourth ports; and 
 a third capacitor coupled between the second and fourth ports. 
 
     
     
       10. The electronic device of  claim 9 , wherein the first conductive traces include first and second segments, the second conductive traces include third and fourth segments, the third conductive traces include fifth and sixth segments, the first capacitor has opposing capacitor electrodes formed from the first and third segments, the second capacitor has opposing capacitor electrodes formed from the second and fifth segments, and the third capacitor has opposing capacitor electrodes formed from the fourth and sixth segments. 
     
     
       11. The electronic device of  claim 8 , wherein the first, second, and third conductive traces wind at least twice in a common direction about the feed point. 
     
     
       12. The electronic device of  claim 6 , further comprising:
 a first phase and magnitude controller coupled between the second port and the first antenna; 
 a second phase and magnitude controller coupled between the third port and the second antenna; and 
 a phased antenna array that includes the first and second antennas and that is configured to convey the radio-frequency signals at a frequency greater than 20 GHz. 
 
     
     
       13. A passive radio-frequency power splitter configured to distribute power from an input port onto first and second output ports, comprising:
 a dielectric substrate; 
 first conductive traces on the dielectric substrate, the first conductive traces extending from a feed point to the first output port and having a coil shape that winds at least once around the feed point; 
 second conductive traces on the dielectric substrate, the second conductive traces extending from the feed point to the second output port and having a coil shape that winds at least once around the feed point; and 
 a feed trace on the dielectric substrate that couples the input port to the feed point. 
 
     
     
       14. The passive radio-frequency power splitter of  claim 13 , wherein the first and second conductive traces are intertwined on the dielectric substrate and concentric about the feed point. 
     
     
       15. The passive radio-frequency splitter of  claim 13 , further comprising:
 a third output port, the passive radio-frequency splitter being configured to distribute the radio-frequency power from the input port onto the third output ports; and 
 third conductive traces on the dielectric substrate, the third conductive traces extending from the feed point to the third output port and having a coil shape that winds at least once around the feed point. 
 
     
     
       16. The passive radio-frequency splitter of  claim 15 , wherein the first, second, and third conductive traces are coupled in parallel between the feed point and the first, second, and third output ports, respectively. 
     
     
       17. A passive radio-frequency power combiner configured to combine radio-frequency power from first and second input ports onto an output port, the passive radio-frequency power combiner comprising:
 a dielectric substrate; 
 first conductive traces on the dielectric substrate, the first conductive traces extending from the first input port to a feed point and having a spiral shape that winds at least once around the feed point; 
 second conductive traces on the dielectric substrate, the second conductive traces extending from the second input port to the feed point and having a spiral shape that winds at least once around the feed point; and 
 a feed trace on the dielectric substrate that couples the feed point to the output port. 
 
     
     
       18. The passive radio-frequency power combiner of  claim 17 , wherein the first and second conductive traces are intertwined on the dielectric substrate and concentric about the feed point. 
     
     
       19. The passive radio-frequency combiner of  claim 17 , further comprising:
 a third input port, the passive radio-frequency splitter being configured to distribute the radio-frequency power from the third input port onto the output port; and 
 third conductive traces on the dielectric substrate, the third conductive traces extending from the third input port to the feed point and having a spiral shape that winds at least once around the feed point. 
 
     
     
       20. The passive radio-frequency splitter of  claim 19 , wherein the first, second, and third conductive traces are coupled in parallel between the feed point and the first, second, and third input ports, respectively.

Description:
FIELD 
     This disclosure relates generally to electronic devices and, more particularly, to electronic devices with wireless communications circuitry. 
     BACKGROUND 
     Electronic devices are often provided with wireless communications capabilities. An electronic device with wireless communications capabilities has wireless communications circuitry with radio-frequency components that include one or more antennas. Wireless transceiver circuitry in the wireless communications circuitry uses the antennas to transmit and receive radio-frequency signals. 
     It can be challenging to form satisfactory radio-frequency wireless communications circuitry for an electronic device. If care is not taken, the radio-frequency components in the wireless communications circuitry can occupy an excessive amount of space and can exhibit unsatisfactory levels of radio-frequency performance. 
     SUMMARY 
     An electronic device may include wireless circuitry for performing wireless communications. The wireless circuitry may include a transceiver, at least first and second antennas, and a passive radio-frequency power distribution circuit such as a Wilkinson power splitter/combiner. The distribution circuit may have at least a first port coupled to the transceiver, a second port coupled to the first antenna, and a third port coupled to the second antenna. The second and third ports may be coupled to the first and second antennas through respective phase and magnitude controllers and/or other passive radio-frequency power distribution circuits. The distribution circuit may include a transformer coupled between the ports. The transformer may have at least two intertwined inductors formed from conductive traces on a dielectric substrate. The intertwined inductors may be concentric about a common point. The intertwined inductors may extend from the common point to the second and third ports. The intertwined inductors may have a coil or spiral shape and may wind around the common point at least once. Intertwining the inductors may serve to minimize the lateral footprint of the distribution circuit in the device. 
     An aspect of the disclosure provides an electronic device. The electronic device can have a dielectric substrate. The electronic device can have a passive radio-frequency power distribution circuit. The passive radio-frequency power distribution circuit can have a first port, a second port, a third port, and a transformer. The transformer can couple the first port to the second and third ports. The transformer can include a first inductor coupled between the first and second ports. The transformer can include a second inductor coupled between the first and third ports. The second inductor can be intertwined with the first inductor on the dielectric substrate. 
     An aspect of the disclosure provides a passive radio-frequency power splitter. The passive radio-frequency power splitter can distribute power from an input port onto first and second output ports. The passive radio-frequency power splitter can have a dielectric substrate. The passive radio-frequency power splitter can have first conductive traces on the dielectric substrate. The first conductive traces can extend from a feed point to the first output port. The first conductive traces can have a coil shape that winds at least once around the feed point. The passive radio-frequency power splitter can have second conductive traces on the dielectric substrate. The second conductive traces can extend from the feed point to the second output port. The second conductive traces can have a coil shape that winds at least once around the feed point. The passive radio-frequency power splitter can have a feed trace on the dielectric substrate. The feed trace can couple the input port to the feed point. 
     An aspect of the disclosure provides a passive radio-frequency power combiner. The passive radio-frequency power combiner can combine radio-frequency power from first and second input ports onto an output port. The passive radio-frequency power combiner can have a dielectric substrate. The passive radio-frequency power combiner can have first conductive traces on the dielectric substrate. The first conductive traces can extend from the first input port to a feed point. The first conductive traces can have a spiral shape that winds at least once around the feed point. The passive radio-frequency power combiner can have second conductive traces on the dielectric substrate. The second conductive traces can extend from the second input port to the feed point. The second conductive traces can have a spiral shape that winds at least once around the feed point. The passive radio-frequency power combiner can have a feed trace on the dielectric substrate. The feed trace can couple the feed point to the output port. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic diagram of an illustrative electronic device having passive radio-frequency power distribution circuitry in accordance with some embodiments. 
         FIG.  2    is a circuit diagram of illustrative passive radio-frequency power distribution circuitry having stages of power splitter/combiners in accordance with some embodiments. 
         FIG.  3    is a circuit diagram of an illustrative 1:2 power splitter/combiner in accordance with some embodiments. 
         FIG.  4    is a diagram of an illustrative 1:2 power splitter/combiner having intertwined inductors in accordance with some embodiments. 
         FIG.  5    is a layout diagram of an illustrative 1:2 power splitter/combiner having intertwined inductors in accordance with some embodiments. 
         FIG.  6    is a circuit diagram of an illustrative 1:3 power splitter/combiner in accordance with some embodiments. 
         FIG.  7    is a diagram of an illustrative 1:3 power splitter/combiner having intertwined inductors in accordance with some embodiments. 
         FIG.  8    is a layout diagram of an illustrative 1:3 power splitter/combiner having intertwined inductors in accordance with some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     An electronic device such as electronic device  10  of  FIG.  1    may be provided with wireless circuitry. The wireless circuitry may include a transceiver and at least first and second antennas. At least one passive radio-frequency power distribution circuit may be coupled between the transceiver and the first and second antennas. The distribution circuit may have a first port coupled to the transceiver, a second port coupled to the first antenna, and a third port coupled to the second antenna. The distribution circuit may include a transformer with at least two intertwined inductors. The intertwined inductors may be formed from conductive traces on a dielectric substrate. The conductive traces may have a coil shape, may be concentric, may extend from the feed point to the second and third ports, and may wind at least once around the feed point. In this way, the distribution circuit may occupy a minimal footprint on the dielectric substrate. 
     Electronic device  10  of  FIG.  1    may be a computing device such as a laptop computer, a desktop computer, a computer monitor containing an embedded computer, a tablet computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wristwatch device, a pendant device, a headphone or earpiece device, a device embedded in eyeglasses or other equipment worn on a user&#39;s head, or other wearable or miniature device, a television, a computer display that does not contain an embedded computer, a gaming device, a navigation device, an embedded system such as a system in which electronic equipment with a display is mounted in a kiosk or automobile, a wireless internet-connected voice-controlled speaker, a home entertainment device, a remote control device, a gaming controller, a peripheral user input device, a wireless base station or access point, equipment that implements the functionality of two or more of these devices, or other electronic equipment. 
     As shown in the schematic diagram  FIG.  1   , device  10  may include components located on or within an electronic device housing such as housing  12 . Housing  12 , which may sometimes be referred to as a case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, metal alloys, etc.), other suitable materials, or a combination of these materials. In some situations, parts or all of housing  12  may be formed from dielectric or other low-conductivity material (e.g., glass, ceramic, plastic, sapphire, etc.). In other situations, housing  12  or at least some of the structures that make up housing  12  may be formed from metal elements. 
     Device  10  may include control circuitry  14 . Control circuitry  14  may include storage such as storage circuitry  16 . Storage circuitry  16  may include hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid-state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Storage circuitry  16  may include storage that is integrated within device  10  and/or removable storage media. 
     Control circuitry  14  may include processing circuitry such as processing circuitry  18 . Processing circuitry  18  may be used to control the operation of device  10 . Processing circuitry  18  may include on one or more microprocessors, microcontrollers, digital signal processors, host processors, baseband processor integrated circuits, application specific integrated circuits, central processing units (CPUs), etc. Control circuitry  14  may be configured to perform operations in device  10  using hardware (e.g., dedicated hardware or circuitry), firmware, and/or software. Software code for performing operations in device  10  may be stored on storage circuitry  16  (e.g., storage circuitry  16  may include non-transitory (tangible) computer readable storage media that stores the software code). The software code may sometimes be referred to as program instructions, software, data, instructions, or code. Software code stored on storage circuitry  16  may be executed by processing circuitry  18 . 
     Control circuitry  14  may be used to run software on device  10  such as satellite navigation applications, internet browsing applications, voice-over-internet-protocol (VOIP) telephone call applications, email applications, media playback applications, operating system functions, etc. To support interactions with external equipment, control circuitry  14  may be used in implementing communications protocols. Communications protocols that may be implemented using control circuitry  14  include internet protocols, wireless local area network (WLAN) protocols (e.g., IEEE 802.11 protocols—sometimes referred to as Wi-Fi®), protocols for other short-range wireless communications links such as the Bluetooth® protocol or other wireless personal area network (WPAN) protocols, IEEE 802.11ad protocols (e.g., ultra-wideband protocols), cellular telephone protocols (e.g., 3G protocols, 4G (LTE) protocols, 5G protocols, etc.), antenna diversity protocols, satellite navigation system protocols (e.g., global positioning system (GPS) protocols, global navigation satellite system (GLONASS) protocols, etc.), antenna-based spatial ranging protocols (e.g., radio detection and ranging (RADAR) protocols or other desired range detection protocols for signals conveyed at millimeter and centimeter wave frequencies), or any other desired communications protocols. Each communications protocol may be associated with a corresponding radio access technology (RAT) that specifies the physical connection methodology used in implementing the protocol. 
     Device  10  may include input-output circuitry  20 . Input-output circuitry  20  may include input-output devices  22 . Input-output devices  22  may be used to allow data to be supplied to device  10  and to allow data to be provided from device  10  to external devices. Input-output devices  22  may include user interface devices, data port devices, and other input-output components. For example, input-output devices  22  may include touch sensors, displays, light-emitting components such as displays without touch sensor capabilities, buttons (mechanical, capacitive, optical, etc.), scrolling wheels, touch pads, key pads, keyboards, microphones, cameras, buttons, speakers, status indicators, audio jacks and other audio port components, digital data port devices, motion sensors (accelerometers, gyroscopes, and/or compasses that detect motion), capacitance sensors, proximity sensors, magnetic sensors, force sensors (e.g., force sensors coupled to a display to detect pressure applied to the display), etc. In some configurations, keyboards, headphones, displays, pointing devices such as trackpads, mice, and joysticks, and other input-output devices may be coupled to device  10  using wired or wireless connections (e.g., some of input-output devices  22  may be peripherals that are coupled to a main processing unit or other portion of device  10  via a wired or wireless link). 
     Input-output circuitry  20  may include wireless circuitry  24  to support wireless communications. Wireless circuitry  24  (sometimes referred to herein as wireless communications circuitry  24 ) may include a baseband processor such as baseband processor  26 , radio-frequency (RF) transceiver circuitry such as transceiver  30 , radio-frequency front end circuitry such as front end circuitry  36 , and one or more antennas  40 . In one embodiment that is described herein as an example, wireless circuitry  24  may include multiple antennas  40  that are arranged into a phased antenna array  42 . Baseband processor  26  may be coupled to transceiver  30  over baseband path  28 . Transceiver  30  may be coupled to antennas  40  over at least one radio-frequency transmission line path  32 . Front end circuitry  36  may be interposed on radio-frequency transmission line path  32  between transceiver  30  and antennas  40 . 
     Wireless circuitry  24  may include a passive radio-frequency power distribution network such as passive radio-frequency power distribution circuitry  34 . Passive radio-frequency power distribution circuitry  34  may be interposed on radio-frequency transmission line path  32  between antennas  40  and transceiver  30  (e.g., between front end circuitry  36  and transceiver  30 ). Passive radio-frequency power distribution circuitry  34  may include passive radio-frequency components that help to distribute radio-frequency power (e.g., transmitted and/or received radio-frequency signals) between transceiver  30  and antennas  40 . As an example, passive radio-frequency power distribution circuitry  34  may include one or more stages of passive radio-frequency power distribution components. The passive radio-frequency power distribution components may include radio-frequency power splitter/combiners. The radio-frequency power splitter/combiners may include Wilkinson power splitter/combiners, for example. 
     In the example of  FIG.  1   , wireless circuitry  24  is illustrated as including only a single baseband processor  26 , a single transceiver  30 , and a single radio-frequency transmission line path  32  for the sake of clarity. In general, wireless circuitry  24  may include any desired number of baseband processors  26 , any desired number of transceivers  30 , and any desired number of antennas  40 . Each baseband processor  26  may be coupled to one or more transceivers  30  over respective baseband paths  28 . Each transceiver  30  may be coupled to one or more antennas  40  over respective radio-frequency transmission line paths  32 . Each radio-frequency transmission line path  32  may have respective front end circuitry  36  and passive radio-frequency power distribution circuitry  34  interposed thereon. If desired, front end circuitry  36  and/or passive radio-frequency power distribution circuitry  34  may be shared by multiple radio-frequency transmission line paths  32 . 
     Radio-frequency transmission line path  32  may be coupled to antenna feeds on one or more antenna  40 . Each antenna feed may, for example, include a positive antenna feed terminal and a ground antenna feed terminal. Radio-frequency transmission line path  32  may have a positive transmission line signal path that is coupled to the positive antenna feed terminal and may have a ground transmission line signal path that is coupled to the ground antenna feed terminal. This example is merely illustrative and, in general, antennas  40  may be fed using any desired antenna feeding scheme. 
     Radio-frequency transmission line path  32  may include transmission lines that are used to route radio-frequency antenna signals within device  10 . Transmission lines in device  10  may include coaxial cables, microstrip transmission lines, stripline transmission lines, edge-coupled microstrip transmission lines, edge-coupled stripline transmission lines, transmission lines formed from combinations of transmission lines of these types, etc. Transmission lines in device  10  such as transmission lines in radio-frequency transmission line path  32  may be integrated into rigid and/or flexible printed circuit boards. In one embodiment, radio-frequency transmission line paths such as radio-frequency transmission line path  32  may also include transmission line conductors integrated within multilayer laminated structures (e.g., layers of a conductive material such as copper and a dielectric material such as a resin that are laminated together without intervening adhesive). The multilayer laminated structures may, if desired, be folded or bent in multiple dimensions (e.g., two or three dimensions) and may maintain a bent or folded shape after bending (e.g., the multilayer laminated structures may be folded into a particular three-dimensional shape to route around other device components and may be rigid enough to hold its shape after folding without being held in place by stiffeners or other structures). All of the multiple layers of the laminated structures may be batch laminated together (e.g., in a single pressing process) without adhesive (e.g., as opposed to performing multiple pressing processes to laminate multiple layers together with adhesive). 
     In performing wireless transmission, baseband processor  26  may provide baseband signals to transceiver  30  over baseband path  28 . Transceiver  30  may include circuitry for converting the baseband signals received from baseband processor  26  into corresponding radio-frequency signals. For example, transceiver  30  may include mixer circuitry for up-converting the baseband signals to radio-frequencies prior to transmission over antennas  40 . Transceiver  30  may also include digital to analog converter (DAC) and/or analog to digital converter (ADC) circuitry for converting signals between digital and analog domains. Transceiver  30  may transmit the radio-frequency signals over antennas  40  via radio-frequency transmission line path  32 , front end circuitry  36 , and passive radio-frequency power distribution circuitry  34 . Antennas  40  may transmit the radio-frequency signals to external wireless equipment by radiating the radio-frequency signals into free space. 
     In performing wireless reception, antennas  40  may receive radio-frequency signals from the external wireless equipment. The received radio-frequency signals may be conveyed to transceiver  30  via radio-frequency transmission line path  32 , front end circuitry  36 , and passive radio-frequency power distribution circuitry  34 . Transceiver  30  may include circuitry for converting the received radio-frequency signals into corresponding baseband signals. For example, transceiver  30  may include mixer circuitry for down-converting the received radio-frequency signals to baseband frequencies prior to conveying the baseband signals to baseband processor  26  over baseband path  28 . 
     Front end circuitry  36  may include radio-frequency front end components that operate on radio-frequency signals conveyed over radio-frequency transmission line path  32 . If desired, the radio-frequency front end components may be formed within one or more radio-frequency front end modules (FEMs). Each FEM may include a common substrate such as a printed circuit board substrate for each of the radio-frequency front end components in the FEM. In these scenarios, passive radio-frequency power distribution circuitry  34  may be formed on the FEM or may be located external to the FEM. If desired, passive radio-frequency power distribution circuitry  34  may be formed as a part of transceiver  30  or may be located external to the transceiver. The radio-frequency front end components in front end circuitry  36  may include switching circuitry (e.g., one or more radio-frequency switches), radio-frequency filter circuitry (e.g., low pass filters, high pass filters, notch filters, band pass filters, multiplexing circuitry, duplexer circuitry, diplexer circuitry, triplexer circuitry, etc.), impedance matching circuitry (e.g., circuitry that helps to match the impedance of antennas  40  to the impedance of radio-frequency transmission line path  32 ), antenna tuning circuitry (e.g., networks of capacitors, resistors, inductors, and/or switches that adjust the frequency response of antennas  40 ), radio-frequency amplifier circuitry (e.g., power amplifier circuitry and/or low-noise amplifier circuitry), radio-frequency coupler circuitry, charge pump circuitry, power management circuitry, digital control and interface circuitry, and/or any other desired circuitry that operates on the radio-frequency signals transmitted and/or received by antennas  40 . 
     While control circuitry  14  is shown separately from wireless circuitry  24  in the example of  FIG.  1    for the sake of clarity, wireless circuitry  24  may include processing circuitry that forms a part of processing circuitry  18  and/or storage circuitry that forms a part of storage circuitry  16  of control circuitry  14  (e.g., portions of control circuitry  14  may be implemented on wireless circuitry  24 ). As an example, baseband processor  26  and/or portions of transceiver  30  (e.g., a host processor on transceiver  30 ) may form a part of control circuitry  14 . 
     Transceiver  30  may include wireless local area network transceiver circuitry that handles WLAN communications bands (e.g., Wi-Fi® (IEEE 802.11) or other WLAN communications bands) such as a 2.4 GHz WLAN band (e.g., from 2400 to 2480 MHz), a 5 GHz WLAN band (e.g., from 5180 to 5825 MHz), a Wi-Fi® 6E band (e.g., from 5925-7125 MHz), and/or other Wi-Fi® bands (e.g., from 1875-5160 MHz), wireless personal area network transceiver circuitry that handles the 2.4 GHz Bluetooth® band or other WPAN communications bands, cellular telephone transceiver circuitry that handles cellular telephone bands (e.g., bands from about 600 MHz to about 5 GHz, 3G bands, 4G LTE bands, 5G New Radio Frequency Range 1 (FR1) bands below 10 GHz, 5G New Radio Frequency Range 2 (FR2) bands between 20 and 60 GHz, etc.), near-field communications (NFC) transceiver circuitry that handles near-field communications bands (e.g., at 13.56 MHz), satellite navigation receiver circuitry that handles satellite navigation bands (e.g., a GPS band from 1565 to 1610 MHz, a Global Navigation Satellite System (GLONASS) band, a BeiDou Navigation Satellite System (BDS) band, etc.), ultra-wideband (UWB) transceiver circuitry that handles communications using the IEEE 802.15.4 protocol and/or other ultra-wideband communications protocols, and/or any other desired radio-frequency transceiver circuitry for covering any other desired communications bands of interest. In scenarios where device  10  handles NFC communications bands, device  10  may form an NFC tag (e.g., a passive or active NFC tag having a smart leakage management engine as described herein), may include an NFC tag integrated into a larger device or structure, or may be a different type of device that handles NFC communications, as examples. Communications bands may sometimes be referred to herein as frequency bands or simply as “bands” and may span corresponding ranges of frequencies. 
     Antennas  40  may be formed using any desired antenna structures. For example, antennas  40  may include antennas with resonating elements that are formed from loop antenna structures, patch antenna structures, inverted-F antenna structures, slot antenna structures, planar inverted-F antenna structures, helical antenna structures, monopole antennas, dipoles, hybrids of these designs, etc. Parasitic elements may be included in antennas  40  to adjust antenna performance. 
     Filter circuitry, switching circuitry, impedance matching circuitry, and other circuitry may be interposed within radio-frequency transmission line path  32 , may be incorporated into front end circuitry  36 , and/or may be incorporated into antennas  40  (e.g., to support antenna tuning, to support operation in desired frequency bands, etc.). These components, sometimes referred to herein as antenna tuning components, may be adjusted (e.g., using control circuitry  14 ) to adjust the frequency response and wireless performance of antennas  40  over time. 
     In general, transceiver  30  may cover (handle) any suitable communications (frequency) bands of interest. The transceiver may convey radio-frequency signals using antennas  40  (e.g., antennas  40  may convey the radio-frequency signals for the transceiver circuitry). The term “convey radio-frequency signals” as used herein means the transmission and/or reception of the radio-frequency signals (e.g., for performing unidirectional and/or bidirectional wireless communications with external wireless communications equipment). Antennas  40  may transmit the radio-frequency signals by radiating the radio-frequency signals into free space (or to freespace through intervening device structures such as a dielectric cover layer). Antennas  40  may additionally or alternatively receive the radio-frequency signals from free space (e.g., through intervening devices structures such as a dielectric cover layer). The transmission and reception of radio-frequency signals by antennas  40  each involve the excitation or resonance of antenna currents on an antenna resonating element in the antenna by the radio-frequency signals within the frequency band(s) of operation of the antennas. 
     In one embodiment that is sometimes described herein as an example, multiple antennas  40  may be arranged in a phased antenna array such as phased antenna array  42 . In this scenario, each antenna  40  may form a respective antenna element of phased antenna array  42 . Phased antenna array  42  may also sometimes be referred to herein as a phased array antenna having antenna elements, where each antenna  40  forms a respective one of the antenna elements. Conveying radio-frequency signals using phased antenna array  42  may allow for greater peak signal gain relative to scenarios where individual antennas  40  are used to convey radio-frequency signals. 
     In satellite navigation system links, cellular telephone links, and other long-range links, radio-frequency signals are typically used to convey data over thousands of feet or miles. In Wi-Fi® and Bluetooth® links at 2.4 and 5 GHz and other short-range wireless links, radio-frequency signals are typically used to convey data over tens or hundreds of feet. In scenarios where millimeter or centimeter wave frequencies are used to convey radio-frequency signals, phased antenna array  42  may convey radio-frequency signals over short distances that travel over a line-of-sight path. To enhance signal reception for millimeter and centimeter wave communications, phased antenna arrays such as phased antenna array  42  may convey radio-frequency signals using beam steering techniques (e.g., schemes in which antenna signal phase and/or magnitude for each antenna in an array are adjusted to perform beam steering). 
     For example, each antenna  40  in phased antenna array  42  may be coupled to a corresponding phase and magnitude controller  38  in front end circuitry  36 . Phase and magnitude controllers  38  may adjust the relative phases and/or magnitudes of the radio-frequency signals that are conveyed by each of the antennas  40  in phased antenna array  42 . The wireless signals that are transmitted or received by phased antenna array  42  in a particular direction may collectively form a corresponding signal beam. The signal beam may exhibit a peak gain that is oriented in a particular pointing direction at a corresponding pointing angle (e.g., based on constructive and destructive interference from the combination of signals from each antenna in the phased antenna array). Control circuitry  14  may adjust phase and magnitude controllers  38  to change the direction of the signal beam over time (e.g., to allow device  10  to continue to communicate with external equipment even if the external equipment moves relative to device  10  over time). This example is merely illustrative and, in general, antennas  40  need not be arranged in a phased antenna array. 
     Passive radio-frequency power distribution circuitry  34  may be used to distribute radio-frequency power (e.g., radio-frequency signals) between transceiver  30  and antennas  40  via phase and magnitude controllers  38  (or between transceiver  30  and other front end components in front end circuitry  36  in scenarios were antennas  40  are not arranged in a phased antenna array). Passive radio-frequency power distribution circuitry  34  may, for example, allow a single port on transceiver  30  to provide radio-frequency signals to multiple antennas  40  in phased antenna array  42 . 
       FIG.  2    is a circuit diagram of passive radio-frequency power distribution circuitry  34  in one example. As shown in  FIG.  2   , passive radio-frequency power distribution circuitry  34  may include one or more cascaded stages  48  of passive radio-frequency power distribution components. In the example of  FIG.  2   , passive radio-frequency power distribution circuitry  34  includes a first stage  48 - 1  and a second stage  48 - 2 . Stage  48 - 1  may be coupled to upstream radio-frequency port  50  of passive radio-frequency power distribution circuitry  34 . Stage  48 - 2  may be coupled between stage  48 - 1  and downstream radio-frequency ports  52  of passive radio-frequency power distribution circuitry  34 . 
     Upstream radio-frequency port  50  may be coupled to transceiver  30  over a first portion of radio-frequency transmission line path  32  ( FIG.  1   ). Each downstream radio-frequency port  52  may be coupled to a respective antenna  40  in phased antenna array  42  via a respective one of the phase and magnitude controllers  38  in front end circuitry  36  ( FIG.  1   ). This is merely illustrative and, in general, downstream radio-frequency ports  52  may be coupled to any desired components in front end circuitry  36  and upstream radio-frequency port  50  may be coupled to any desired components in transceiver  30  or to a radio-frequency front end component in front end circuitry  36 . 
     The passive radio-frequency power distribution components in stages  48  may include passive radio-frequency power splitter/combiners. The power splitter/combiners may include one or more four-port power splitter/combiners  44  (sometimes referred to herein as 1:3 power splitter/combiners  44 ) and/or may include one or more three-port power/splitter combiners  46  (sometimes referred to herein as 1:2 power splitter/combiners  46 ). In one embodiment that is sometimes described herein as an example, the power splitter/combiners in passive radio-frequency power distribution circuitry  34  are Wilkinson power splitter/combiners (e.g., 1:3 power splitter/combiners  44  may be 1:3 Wilkinson power splitter/combiners and 1:2 power splitter/combiners  46  may be 1:2 Wilkinson power splitter/combiners). In the example of  FIG.  2   , stage  48 - 1  includes one 1:3 power splitter/combiner  44  and stage  48 - 2  includes three 1:2 power splitter/combiners  46 . This may allow passive radio-frequency power distribution circuitry  34  to distribute power between a single port of transceiver  30  and six antennas  40  in phased antenna array  42  (e.g., in scenarios where phased antenna array  42  of  FIG.  1    includes six antennas  40 ). 
     In the example of  FIG.  2   , one 1:3 power splitter/combiner  44  in stage  48 - 1  may replace the use of two stages of 1:2 power splitter/combiners  46  coupled between stage  48 - 2  and upstream radio-frequency port  50 . This may serve to minimize the area required to form passive radio-frequency power distribution circuitry  34 , thereby freeing up more space for other components in device  10 . This may also serve to minimize wasted power that would otherwise be incurred by a dummy load (e.g., in scenarios where three stages  48  of 1:2 power splitter/combiners are used). 
     This example is merely illustrative. In general, each stage  48  may include any desired number of 1:3 power splitter/combiners  44  and any desired number of 1:2 power splitter/combiners  46 . Passive radio-frequency power distribution circuitry  34  may include any desired number of stages  48 . Passive radio-frequency power distribution circuitry  34  may include any desired number of downstream radio-frequency ports  52  (e.g., a respective downstream radio-frequency port  52  for each antenna  40  in phased antenna array  42  of  FIG.  1   ) and any desired number of upstream radio-frequency ports  50 . If desired, passive radio-frequency power distribution circuitry  34  may include power splitter/combiners having more than four ports (e.g., 1:4 power splitter/combiners, 1:5 power splitter/combiners, 1:6 power splitter/combiners, etc.). 
     Passive radio-frequency power distribution circuitry  34  may be used to convey radio-frequency signals from upstream radio-frequency port  50  to downstream radio-frequency ports  52  (e.g., for transmission by phased antenna array  42 ) and/or may be used to convey radio-frequency signals from downstream radio-frequency ports  52  to upstream radio-frequency port  50  (e.g., radio-frequency signals received by phased antenna array  42  from external communications equipment). Because 1:3 power splitter/combiner  44  and 1:2 power splitter/combiners  46  are passive circuits, passive radio-frequency power distribution circuitry  34  may be used to equivalently convey radio-frequency signals in either direction between antennas  40  and transceiver  30 . 
     In scenarios where passive radio-frequency power distribution circuitry  34  is used to convey radio-frequency signals from upstream radio-frequency port  50  to downstream radio-frequency ports  52  (e.g., in an uplink direction), each 1:3 power splitter/combiner  44  may serve as a 1:3 power splitter. Similarly, each 1:2 power splitter/combiner  46  may serve as a 1:2 power splitter (e.g., passive radio-frequency power distribution circuitry  34  may serve as a power splitter or divider that distributes radio-frequency power from upstream radio-frequency port  50  across each downstream radio-frequency port  52 ). In these scenarios where passive radio-frequency power distribution circuitry  34  is being used to transmit radio-frequency signals over antennas  40 , the 1:3 power splitter/combiners  44  and the 1:2 power splitter/combiners  46  in passive radio-frequency power distribution circuitry  34  may sometimes be referred to as power splitters, radio-frequency power splitters, power dividers, radio-frequency power dividers, Wilkinson power dividers, or Wilkinson power splitters. 
     In scenarios where passive radio-frequency power distribution circuitry  34  is used to convey radio-frequency signals from downstream radio-frequency ports  52  to upstream radio-frequency port  50  (e.g., in a downlink direction), each 1:3 power splitter/combiner  44  may serve as a 1:3 power combiner. Similarly, each 1:2 power splitter/combiner  46  may serve as a 1:2 power combiner (e.g., passive radio-frequency power distribution circuitry  34  may serve as a power combiner that combines radio-frequency power from downstream radio-frequency ports  52  onto upstream radio-frequency port  50 ). In these scenarios where passive radio-frequency power distribution circuitry  34  is being used to receive radio-frequency signals from antennas  40 , the 1:3 power splitter/combiners  44  and the 1:2 power splitter/combiners  46  in passive radio-frequency power distribution circuitry  34  may sometimes be referred to as power combiners, radio-frequency power combiners, or Wilkinson power combiners. 
     1:3 power splitter/combiners  44  and the 1:2 power splitter/combiners  46  may be dedicated power combiners in scenarios where passive radio-frequency power distribution circuitry  34  is used only to receive radio-frequency signals from antennas  40 . 1:3 power splitter/combiners  44  and the 1:2 power splitter/combiners  46  may be dedicated power splitters in scenarios where passive radio-frequency power distribution circuitry  34  is used only to transmit radio-frequency signals over antennas  40 . However, because 1:2 power splitter/combiners  46  and 1:3 power splitter/combiners  44  are passive components, 1:2 power splitter/combiners  46  and 1:3 power splitter/combiners  44  may serve as power splitters when passive radio-frequency power distribution circuitry  34  is transmitting radio-frequency signals over antennas  40  and may serve as power combiners when passive radio-frequency power distribution circuitry  34  is receiving radio-frequency signals from antennas  40 . 1:3 power splitter/combiners  44  and the 1:2 power splitter/combiners  46  in passive radio-frequency power distribution circuitry  34  may sometimes be referred to collectively herein as power splitter/combiners, radio-frequency power splitter/combiners, radio-frequency power distribution circuits, passive radio-frequency power distribution circuits, passive radio-frequency power splitter/combiners, Wilkinson power splitter/combiners, Wilkinson circuits, or Wilkinson power distribution circuits. 
       FIG.  3    is a circuit diagram of an exemplary 1:2 power splitter/combiner  46 . As shown in  FIG.  3   , 1:2 power splitter/combiner  46  may have an upstream radio-frequency port such as upstream port  54  (sometimes referred to herein as upstream terminal  54 ). Upstream port  54  may be coupled to components in wireless circuitry  24  that are upstream from 1:2 power splitter/combiner  46 . For example, upstream port  54  may be coupled to a downstream port on 1:3 power splitter/combiner  44  of  FIG.  2   , may be coupled to a downstream port on a different power splitter/combiner in passive radio-frequency power distribution circuitry  34 , may be coupled to upstream radio-frequency port  50  of  FIG.  2   , etc. 
     1:2 power splitter/combiner  46  may also have two downstream radio-frequency ports such as downstream ports  56  (e.g., a first downstream port  56 - 1  and a second downstream port  56 - 2 ). Downstream ports  56  may sometimes be referred to herein as downstream terminals  56 . Each downstream port  56  may be coupled to a respective component in wireless circuitry  24  that is downstream from 1:2 power splitter/combiner  46 . For example, downstream port  56 - 1  may be coupled to a first antenna  40  in phased antenna array  42  (e.g., via a first phase and magnitude controller  38  of  FIG.  1   ) whereas downstream port  56 - 2  is coupled to a second antenna  40  in phased antenna array  42  (e.g., via a second phase and magnitude controller  38  of  FIG.  1   ). As another example, downstream ports  56 - 1  and  56 - 2  may be coupled to the upstream port of respective 1:2 power splitter/combiners  46 , the upstream port of respective 1:3 power splitter/combiners  44 , or the upstream port of any other desired power splitter/combiners in passive radio-frequency power distribution circuitry  34 . 
     In scenarios where 1:2 power splitter/combiner  46  is being used to transmit radio-frequency signals over antennas  40  (e.g., where 1:2 power splitter/combiner  46  is a 1:2 power splitter), upstream port  54  forms an input port and downstream ports  56  form output ports of 1:2 power splitter/combiner  46 . In scenarios where 1:2 power splitter/combiner  46  is being used to receive radio-frequency signals from antennas  40  (e.g., where 1:2 power splitter/combiner  46  is a 1:2 power combiner), upstream port  54  forms an output port and downstream ports  56  form input ports of 1:2 power splitter/combiner  46 . 
     1:2 power splitter/combiner  46  may include a transformer such as transformer  58 . Transformer  58  may be coupled between upstream port  54  and downstream ports  56 . Transformer  58  may include a set of inductors  60  coupled in parallel between upstream port  54  and downstream ports  56 . For example, as shown in  FIG.  3   , transformer  58  may include a first inductor  60 - 1  coupled between upstream port  54  and downstream port  56 - 1  and may include a second inductor  60 - 2  coupled between upstream port  54  and downstream port  56 - 2 . 
     1:2 power splitter/combiner  46  may include a capacitor such as capacitor  72 . Capacitor  72  may be coupled between downstream ports  56 - 1  and  56 - 2 . 1:2 power splitter/combiner  46  may also include capacitors such as capacitors  64 ,  66 ,  68 , and/or  70 . Capacitor  66  may be coupled between upstream port  54  and reference potential  62  at the upstream side of inductor  60 - 1 . Reference potential  62  may be a ground potential or another reference potential in device  10 . Capacitor  64  may be coupled between downstream port  56 - 1  and reference potential  62  at the downstream side of inductor  60 - 1 . Capacitor  70  may be coupled between downstream port  56 - 2  and reference potential  62  at the downstream side of inductor  60 - 2 . Capacitor  68  may be coupled between upstream port  54  and reference potential  62  at the upstream side of inductor  60 - 2 . 
     In one embodiment that is described herein as an example, capacitors  66 ,  68 ,  64 ,  70 , and  72  are distributed capacitors that exhibit distributed capacitances between conductive traces in 1:2 power splitter/combiner  46 . This is merely illustrative and, if desired, one or more of capacitors  66 ,  68 ,  64 ,  70 , and  72  may be discrete capacitors (e.g., surface mount technology (SMT) capacitors). Transformer  58  and capacitors  66 ,  68 ,  64 ,  70 , and  72  may serve to distribute radio-frequency power at upstream port  54  across downstream ports  56 - 1  and  56 - 2  (e.g., in scenarios where 1:2 power splitter/combiner  46  is transmitting radio-frequency signals over antennas  40 ) and/or to combine radio-frequency power at downstream ports  56 - 1  and  56 - 2  onto upstream port  54 . 
     In some scenarios, inductors  60 - 1  and  60 - 2  in transformer  58  are formed from two laterally-separated inductive coils on an underlying substrate. However, forming inductors  60 - 1  and  60 - 2  from two laterally-separated inductive coils may cause transformer  58  to occupy an excessively large lateral footprint in device  10 , thereby minimizing the amount of space in device  10  that can be used for other components. In order to minimize the lateral footprint of transformer  58 , inductors  60 - 1  and  60 - 2  may be intertwined inductors (e.g., intertwined inductors concentric about a single point). 
       FIG.  4    is a diagram showing how 1:2 power splitter/combiner  46  may include intertwined inductors  60 - 1  and  60 - 2 . As shown in  FIG.  4   , upstream port  54  may be coupled to transformer  58  at feed point  88  (e.g., using a conductive feed trace on an underlying dielectric substrate). A capacitance such as capacitance  74  may be coupled between upstream port  54  and reference potential  62 . Capacitance  74  may, for example, be the capacitance associated with capacitors  66  and  68  of  FIG.  3   . 
     Inductor  60 - 1  may be formed from conductive traces  92 . Conductive traces  92  may have a planar spiral or coil shape and may wind (wrap) around feed point  88  (e.g., in a counter-clockwise direction or, as shown in the example of  FIG.  4   , in a clockwise direction about feed point  88 ). Conductive traces  92  and thus inductor  60 - 1  may terminate at downstream port  56 - 1 . Coiling conductive traces  92  in this way may configure conductive traces  92  to exhibit a desired inductance between feed point  88  and downstream port  56 - 1  (e.g., the inductance of inductor  60 - 1 ). 
     Inductor  60 - 2  may be formed from conductive traces  90  (shown in bold in  FIG.  4   ). Conductive traces  90  may have a planar spiral or coil shape and may wind (wrap) around feed point  88 . Conductive traces  90  may wind around feed point  88  in the same direction as conductive traces  92  (e.g., conductive traces  90  may wind around feed point  88  in a clockwise direction about feed point  88 ). Conductive traces  90  and thus inductor  60 - 2  may terminate at downstream port  56 - 2 . Coiling conductive traces  90  in this way may configure conductive traces  90  to exhibit a desired inductance between feed point  88  and downstream port  56 - 2  (e.g., the inductance of inductor  60 - 2 ). 
     As shown in  FIG.  4   , when configured in this way, conductive traces  92  and thus inductor  60 - 1  may be intertwined with conductive traces  90  and inductor  60 - 2  (e.g., on an underlying dielectric substrate). Each segment of conductive traces  92  except for the first and last half-turn around feed point  88  may be laterally interposed between two segments of conductive traces  90 . Similarly, each segment of conductive traces  90  except for the first and last half-turn around feed point  88  may be laterally interposed between two segments of conductive traces  92 . In other words, conductive traces  92  (inductor  60 - 1 ) and conductive traces  90  (inductor  60 - 2 ) may be arranged in a common centroid configuration in which the conductive traces and inductors are concentric about a common point or axis (e.g., about feed point  88  or an axis running through feed point  88  parallel to the Z-axis of  FIG.  4   ). This may configure transformer  58  to exhibit the lateral footprint that is approximately the same as the lateral footprint of only a single one of inductors  60 - 1  or  60 - 2 , rather than a lateral footprint that is greater than or equal to the lateral footprint of inductors  60 - 1  and  60 - 2  combined. This may serve to minimize the lateral footprint and thus the space consumed by transformer  58  in device  10 . 
     In the example of  FIG.  4   , conductive traces  92  and  90  (inductors  60 - 1  and  60 - 2 ) each make three complete turns (e.g., 360-degree passes) around feed point  88  in winding from feed point  88  to downstream ports  56 - 1  and  56 - 2 , respectively. This is merely illustrative. In other embodiments, conductive traces  92  and  90  may each make two complete turns around feed point  88 , four complete turns around feed point  88 , more than four complete turns around feed point  88 , fewer than two complete turns around feed point  88 , a non-integer number of turns around feed point  88 , etc. 
     As shown in  FIG.  4   , capacitor  64  may be coupled between conductive traces  92  and reference potential  62  (e.g., at downstream port  56 - 1 ). Capacitor  70  may be coupled between conductive traces  90  and reference potential  62  (e.g., at downstream port  56 - 2 ). Conductive traces  92  may include segment  84 . Conductive traces  90  may include segment  86 . Segments  86  and  84  may form respective capacitor electrodes for capacitance  78 . Conductive traces  92  may also include segment  82 . Conductive traces  90  may also include segment  80 . Segments  80  and  82  may form respective capacitor electrodes for capacitance  76 . Capacitance  78  and capacitance  76  may collectively form capacitor  72  of  FIG.  3   , for example. 
       FIG.  5    is a top-down layout diagram of 1:2 power splitter/combiner  46 . As shown in  FIG.  5   , 1:2 power splitter/combiner  46  may be formed on a dielectric substrate such as dielectric substrate  94 . Dielectric substrate  94  may, for example, include multiple vertically-stacked dielectric layers (e.g., dielectric layers that are stacked in the direction of the Z-axis of  FIG.  5   ). 
     Upstream port  54  may be coupled to feed trace  106 . Feed trace  106  may extend into the central portion (region) of transformer  58 . Feed trace  106  may, for example, be patterned onto a first dielectric layer of dielectric substrate  94 . Conductive traces  90  for inductor  60 - 2  and conductive traces  92  for inductor  60 - 1  may be patterned onto a second dielectric layer of dielectric substrate  94  (e.g., a dielectric layer that is layered over the first dielectric layer of dielectric substrate  94 ). One or more conductive through vias such as conductive vias  108  may couple feed trace  106  to conductive traces  92  and  90  (e.g., at and/or adjacent feed point  88 ). Conductive traces  90  and  92  may extend from opposing sides of feed point  88 . 
     Conductive ground traces such as ground traces  100  may be patterned onto dielectric substrate  94 . If desired, ground traces  100  may be patterned on both the first and second dielectric layers of dielectric substrate  94 . In this example, conductive vias may couple the ground traces on each of the dielectric layers together. Ground traces  100  may be held at a reference potential (e.g., reference potential  62  of  FIGS.  3  and  4   ). Feed trace  106  may be laterally separated from ground traces  100  by one or more gaps  104 . The capacitance associated with gap(s)  104  may form capacitance  74  of  FIG.  4    and the capacitance of capacitors  66  and  68  of  FIG.  3   , for example. 
     Conductive traces  92  and  90  may both be intertwined as the conductive traces spiral from feed point  88  outwards to downstream ports  56 - 1  and  56 - 2  (e.g., conductive traces  92  and  90  may be interspersed or interleaved as the conductive traces wind around feed point  88 ). This may configure inductors  60 - 1  and  60 - 2  and thus transformer  58  to exhibit a length  96  and a width  98 . Length  96  and width  98  may define the lateral footprint of transformer  58 . Length  96  may be equal to width  98  or may be different from width  98 . As just one example, width  98  may be between 40-70 microns whereas length  96  is between 50-80 microns. The lateral footprint of transformer  58  may be similar to the lateral footprint of just one of inductors  60 - 1  or  60 - 2 , thereby minimizing the overall footprint of 1:2 power splitter/combiner  46 , despite the fact that 1:2 power splitter/combiner  46  includes two separate inductors that are coupled in parallel between upstream port  54  and downstream ports  56 - 1  and  56 - 2 . 
     As shown in  FIG.  5   , at downstream port  56 - 1 , segment  82  of conductive traces  92  may be separated from ground traces  100  by gap  112 . Similarly, at downstream port  56 - 2 , segment  86  of conductive traces  90  may be separated from ground traces  100  by gap  116 . The capacitance associated with gap  112  may form capacitor  64  of  FIGS.  3  and  4   , for example. Similarly, the capacitance associated with gap  116  may form capacitor  70  of  FIGS.  3  and  4   . 
     Segment  80  of conductive traces  90  may extend parallel to segment  82  of conductive traces  92 . Segment  82  may be separated from segment  80  by gap  110 . Similarly, segment  84  of conductive traces  92  may extend parallel to segment  86  of conductive traces  90 . Segment  84  may be separated from segment  86  by gap  114 . The capacitance associated with gap  110  may form capacitance  76  of  FIG.  4   , for example. Similarly, the capacitance associated with gap  114  may form capacitance  70  of  FIG.  4   . In other words, the capacitance associated with gaps  110  and  114  may collectively form capacitor  72  of  FIG.  3   . 
     The example of  FIG.  5    is merely illustrative. Conductive traces  90  and  92  may have other shapes concentric about feed point  88  if desired (e.g., conductive traces  90  and  92  may have a rectangular spiral shape as shown in  FIG.  5   , a circular spiral shape, an elliptical spiral shape, shapes with any desired number of straight and/or curved segments, combinations of these, etc.). 
       FIG.  6    is a circuit diagram of an exemplary 1:3 power splitter/combiner  44 . As shown in  FIG.  6   , 1:3 power splitter/combiner  44  may have upstream port  54  and three downstream ports  56  such as downstream ports  56 - 1 ,  56 - 2 , and  56 - 3 . Upstream port  54  of  FIG.  6    may be coupled to components in wireless circuitry  24  that are upstream from 1:3 power splitter/combiner  44 . For example, upstream port  54  may be coupled to a downstream port on another 1:3 power splitter/combiner  44 , may be coupled to a downstream port on a given 1:2 power splitter/combiner  46 , may be coupled to a downstream port on a different power splitter/combiner in passive radio-frequency power distribution circuitry  34 , may be coupled to upstream radio-frequency port  50  of  FIG.  2   , etc. Each downstream port  56  of  FIG.  6    may be coupled to a respective component in wireless circuitry  24  that is downstream from 1:3 power splitter/combiner  44  (e.g., respective antennas  40  in phased antenna array  42 , respective upstream ports of other power splitter/combiners, etc.). 
     In scenarios where 1:3 power splitter/combiner  44  is being used to transmit radio-frequency signals over antennas  40  (e.g., where 1:3 power splitter/combiner  44  is a 1:3 power splitter), upstream port  54  forms an input port and downstream ports  56  form output ports of 1:3 power splitter/combiner  44 . In scenarios where 1:3 power splitter/combiner  44  is being used to receive radio-frequency signals from antennas  40  (e.g., where 1:3 power splitter/combiner  44  is a 1:3 power combiner), upstream port  54  forms an output port and downstream ports  56  form input ports of 1:3 power splitter/combiner  44 . 
     1:3 power splitter/combiner  44  may include a transformer such as transformer  118 . Transformer  118  may be coupled between upstream port  54  and downstream ports  56 . Transformer  118  may include a set of inductors  60  coupled in parallel between upstream port  54  and downstream ports  56 . For example, as shown in  FIG.  6   , transformer  118  may include a first inductor  60 - 1  coupled between upstream port  54  and downstream port  56 - 1 , may include a second inductor  60 - 2  coupled between upstream port  54  and downstream port  56 - 2 , and may include a third inductor  60 - 3  coupled between upstream port  54  and downstream port  56 - 3 . In general, there may be as many inductors  60  as there are downstream ports  56  in the power splitter/combiners in passive radio-frequency power distribution circuitry  34 . 
     1:3 power splitter/combiner  44  may include capacitors such as capacitors  120 ,  122 ,  124 ,  126 ,  128 ,  130 ,  132 ,  134 , and  136 . Capacitor  132  may be coupled between downstream ports  56 - 1  and  56 - 2 . Capacitor  134  may be coupled between downstream ports  56 - 2  and  56 - 3 . Capacitor  136  may be coupled between downstream ports  56 - 1  and  56 - 3 . Capacitor  120  may be coupled between upstream port  54  and reference potential  62  at the upstream side of inductor  60 - 1 . Capacitor  122  may be coupled between upstream port  54  and reference potential  62  at the upstream side of inductor  60 - 2 . Capacitor  124  may be coupled between upstream port  54  and reference potential  62  at the upstream side of inductor  60 - 3 . Capacitor  126  may be coupled between downstream port  56 - 1  and reference potential  62  at the downstream side of inductor  60 - 1 . Capacitor  128  may be coupled between downstream port  56 - 2  and reference potential  62  at the downstream side of inductor  60 - 2 . Capacitor  130  may be coupled between downstream port  56 - 3  and reference potential  62  at the downstream side of inductor  60 - 3 . 
     In one embodiment that is described herein as an example, capacitors  120 - 136  are distributed capacitors that exhibit distributed capacitances between conductive traces in 1:3 power splitter/combiner  44 . This is merely illustrative and, if desired, one or more of these capacitors may be discrete capacitors (e.g., surface mount technology (SMT) capacitors). Transformer  118  and capacitors  120 - 136  may serve to distribute radio-frequency power at upstream port  54  across downstream ports  56 - 1 ,  56 - 2 , and  56 - 3  (e.g., in scenarios where 1:3 power splitter/combiner  44  is transmitting radio-frequency signals over antennas  40 ) and/or to combine radio-frequency power at downstream ports  56 - 1 ,  56 - 2 , and  56 - 3  onto upstream port  54 . 
     In order to minimize the lateral footprint of transformer  118 , inductors  60 - 1 ,  60 - 2 , and  60 - 3  may be intertwined inductors (e.g., intertwined inductors that are concentric about a single point).  FIG.  7    is a diagram showing how 1:3 power splitter/combiner  44  may include intertwined inductors  60 - 1 ,  60 - 2 , and  60 - 3 . As shown in  FIG.  7   , upstream port  54  may be coupled to transformer  118  at feed point  88  (e.g., using a conductive feed trace on an underlying dielectric substrate). A capacitance such as capacitance  138  may be coupled between upstream port  54  and reference potential  62 . Capacitance  138  may, for example, be the capacitance associated with capacitors  120 ,  122 , and  124  of  FIG.  6   . 
     Inductor  60 - 1  may be formed from conductive traces  92  and inductor  60 - 2  may be formed from conductive traces  90 , similar to as described above in connection with  FIG.  4   . Inductor  60 - 3  in 1:3 power splitter/combiner  44  may be formed from conductive traces  140  (shown as dashed lines in  FIG.  7   ). Conductive traces  140  and the feed trace for upstream port  54  may extend from opposing sides of feed point  88 . Conductive traces  140  may have a planar spiral or coil shape and may wind (wrap) around feed point  88  in the same direction as conductive traces  90  and  92  (e.g., in a clockwise direction about feed point  88 ). Conductive traces  140  and thus inductor  60 - 3  may terminate at downstream port  56 - 3 . Coiling conductive traces  140  in this way may configure conductive traces  140  to exhibit a desired inductance between feed point  88  and downstream port  56 - 3  (e.g., the inductance of inductor  60 - 3 ). 
     As shown in  FIG.  7   , when configured in this way, conductive traces  92  and thus inductor  60 - 1  may be intertwined with both conductive traces  90  (inductor  60 - 2 ) and conductive traces  140  (inductor  60 - 3 ). Each segment of conductive traces  92  except for the first and last quarter-turn around feed point  88  may be laterally interposed between a corresponding segment of conductive traces  90  and a corresponding segment of conductive traces  140 . Similarly, each segment of conductive traces  90  except for the first and last quarter-turn around feed point  88  may be laterally interposed between a corresponding segment of conductive traces  92  and a corresponding segment of conductive traces  140 . Each segment of conductive traces  140  except for the first and last quarter-turn around feed point  88  may be laterally interposed between a corresponding segment of conductive traces  92  and a corresponding segment of conductive traces  90 . 
     In other words, conductive traces  92  (inductor  60 - 1 ), conductive traces  90  (inductor  60 - 2 ), and conductive traces  140  (inductor  60 - 3 ) may be arranged in a common centroid configuration in which the conductive traces and inductors are concentric about a common point or axis (e.g., feed point  88  or an axis running through feed point  88  parallel to the Z-axis of  FIG.  7   ). This may configure transformer  118  to exhibit a lateral footprint similar to only a single one of inductors  60 - 1 ,  60 - 2 , or  60 - 3  rather than a lateral footprint that is greater than or equal to the lateral footprint of inductors  60 - 1 ,  60 - 2 , and  60 - 3  combined. This may serve to minimize the lateral footprint and thus the space consumed by transformer  118  in device  10 . 
     In the example of  FIG.  7   , conductive traces  92 ,  90 , and  140  (inductors  60 - 1 ,  60 - 2 , and  60 - 3 ) each make two complete turns (e.g., 360-degree passes) around feed point  88  in winding from feed point  88  to downstream ports  56 - 1 ,  56 - 2 , and  56 - 3 , respectively. This is merely illustrative. In other embodiments, conductive traces  92 ,  90 , and  140  may each make three complete turns around feed point  88 , one complete turn around feed point  88 , more than three complete turns around feed point  88 , a non-integer number of turns around feed point  88 , etc. If desired, conductive traces  92 ,  90 , and/or  140  may each have the same shape (e.g., a rectangular spiral shape). 
     As shown in  FIG.  7   , capacitor  126  may be coupled between conductive traces  92  and reference potential  62  (e.g., at downstream port  56 - 1 ). Capacitor  128  may be coupled between conductive traces  90  and reference potential  62  (e.g., at downstream port  56 - 2 ). Capacitor  130  may be coupled between conductive traces  140  and reference potential  62  (e.g., at downstream port  56 - 3 ). 
     Conductive traces  92  may include segment  148 . Conductive traces  140  may include segment  86 . Segments  86  and  84  may form respective capacitor electrodes for capacitor  136 . Conductive traces  92  may also include segment  150 . Conductive traces  90  may include segment  152 . Segments  150  and  152  may form respective capacitor electrodes for capacitor  132 . Conductive traces  140  may include segment  144 . Conductive traces  90  may include segment  142 . Segments  142  and  144  may form respective capacitor electrodes for capacitor  134 . 
       FIG.  8    is a top-down layout diagram of 1:3 power splitter/combiner  44 . As shown in  FIG.  8   , conductive traces  90  for inductor  60 - 2 , conductive traces  92  for inductor  60 - 1 , and conductive traces  140  for inductor  60 - 3  may be patterned onto dielectric substrate  94 . One or more conductive through vias such as conductive vias  108  may couple feed trace  106  to conductive traces  92 ,  90 , and  140  (e.g., at and/or adjacent feed point  88 ). Feed trace  106  may be laterally separated from ground traces  100  by one or more gaps  154 . The capacitance associated with gap(s)  154  may form capacitance  138  of  FIG.  7    and the capacitance of capacitors  120 - 124  of  FIG.  6   , for example. 
     Conductive traces  92 ,  90 , and  140  may intertwined as the conductive traces spiral from feed point  88  outwards to downstream ports  56 - 1 ,  56 - 2 , and  56 - 3  (e.g., conductive traces  92 ,  90 , and  140  may be interspersed or interleaved as the conductive traces wind around feed point  88 ). This may configure inductors  60 - 1 ,  60 - 2 , and  60 - 3  and thus transformer  58  to exhibit a length  158  and a width  156 . Length  158  and width  156  may define the lateral footprint of transformer  118 . Length  158  may be equal to width  156  or may be different from width  156 . As just one example, width  156  may be between 40-90 microns whereas length  158  is between 50-100 microns. The lateral footprint of transformer  118  may be similar to the lateral footprint of just one of inductors  60 - 1 ,  60 - 2 , or  60 - 3 , thereby minimizing the overall footprint of 1:3 power splitter/combiner  44 , despite the fact that 1:3 power splitter/combiner  44  includes three separate inductors that are coupled in parallel between upstream port  54  and downstream ports  56 - 1 ,  56 - 2 , and  56 - 3 . 
     As shown in  FIG.  8   , at downstream port  56 - 1 , segment  148  of conductive traces  92  may be separated from ground traces  100  by gap  164 . At downstream port  56 - 2 , segment  152  of conductive traces  90  may be separated from ground traces  100  by gap  162 . At downstream port  56 - 3 , segment  144  of conductive traces  140  may be separated from ground traces  100  by gap  170 . The capacitance associated with gap  164  may form capacitor  126  of  FIGS.  6  and  7   , for example. Similarly, the capacitance associated with gap  162  may form capacitor  128  and the capacitance associated with gap  170  may form capacitor  130  of  FIGS.  6  and  7   . 
     Segment  152  of conductive traces  90  may extend parallel to segment  150  of conductive traces  92 . Segment  152  may be separated from segment  150  by gap  160 . Segment  144  of conductive traces  140  may extend parallel to segment  142  of conductive traces  90 . Segment  144  may be separated from segment  142  by gap  168 . Segment  148  of conductive traces  92  may extend parallel to segment  146  of conductive traces  140 . Segment  148  may be separated from segment  146  by gap  166 . The capacitance associated with gap  166  may form capacitor  136 , the capacitance associated with gap  168  may form capacitor  134 , and the capacitance associated with gap  160  may form capacitor  132  of  FIG.  6   , for example. 
     The example of  FIG.  8    is merely illustrative. Conductive traces  90 ,  92 , and  140  may have other shapes concentric about feed point  88  if desired (e.g., conductive traces  90 ,  92 , and  140  may have a rectangular spiral shape, circular spiral shape, elliptical spiral shape, combinations of these, shapes with any desired number of straight and/or curved segments, etc.). The structures of 1:2 power splitter/combiner  46  and 1:3 power splitter/combiner  44  may be scaled to provide passive radio-frequency power distribution circuitry  34  with power splitter/combiners of any desired size (e.g., 1:4 power splitter/combiners, 1:5 power splitter/combiners, 1:6 power splitter/combiners, etc.). 
     1:2 power splitter/combiner  46  and 1:3 power splitter/combiner  44  may still exhibit satisfactory radio-frequency performance despite the superposition of inductors  60 - 1 ,  60 - 2 , and  60 - 3  within the same lateral footprint on dielectric substrate  94 . The power splitter/combiner may, for example, exhibit satisfactory impedance matching at each upstream port and each downstream port in the frequency bands handled by antennas  40 . The power splitter/combiner may also exhibit sufficiently low insertion loss and a satisfactory phase response between each combination of the upstream/downstream ports in the frequency bands handled by antennas  40 . In addition, the power splitter/combiner may exhibit satisfactory radio-frequency isolation between each of the upstream/downstream ports. 
     The foregoing is merely illustrative and various modifications can be made to the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20200908
Publication Date: 20230214
Grant Date: 20230214
Priority Date: 20200908
Inventors: HU, SONG
EMAMI-NEYESTANAK, SOHRAB
Assignee: APPLE INC
CPC Classifications: [{"code": "H01Q3/28", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B1/401", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/38", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q7/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q3/36", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04B1/40", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01Q3/36", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q3/36", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q3/28", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q7/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01Q1/38", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 80266954