Active tunable multiband filter circuit

Abstract

The invention relates to an active tunable multiband filter circuit. A wireless circuit may include a first filter circuit configured to output a signal in a first frequency range; a second filter circuit configured to output a signal in a second frequency range different from the first frequency range; and a signal combiner having a first input coupled to the first filter circuit and having a second input coupled to the second filter circuit. The wireless circuitry may further include: a first switchable impedance matching circuit coupled between an antenna and the first filter circuit; and a second switchable impedance matching circuit, wherein the second switchable impedance matching circuit is coupled between the antenna and the second filter circuit. The first filter circuit and the second filter circuit may be active filters, such as low-pass to band-pass conversion filters capable of operating in different frequency bands.

Description

[0001] This application claims priority to U.S. Patent Application No. 18 / 805,380, filed August 14, 2025, and U.S. Patent Application No. 18 / 805,377, filed August 14, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates in general to electronic devices, and more specifically to electronic devices having wireless communication circuitry. Background Technology

[0003] Electronic devices may possess wireless communication capabilities. Electronic devices with wireless communication capabilities have wireless communication circuitry, which includes one or more antennas. The wireless transceiver circuitry within the wireless communication circuitry uses the antennas to transmit and receive radio frequency signals.

[0004] The radio frequency signal received by the antenna can be fed to a corresponding low-noise amplifier via an acoustic filter. These low-noise amplifiers are configured to amplify the low-power analog signal into a high-power signal for processing at the receiver. The acoustic filter is a passive bandpass filter, which is costly to implement. Designing the filter and amplifier circuitry for the receiver can be challenging. Summary of the Invention

[0005] One aspect of this disclosure provides a circuit comprising: a first filter circuit configured to output a signal in a first frequency range; a second filter circuit configured to output a signal in a second frequency range different from the first frequency range; a signal combiner having a first input coupled to the first filter circuit and a second input coupled to the second filter circuit; and a first switchable matching circuit coupled to the input of the first filter circuit. The circuit may further comprise: a second switchable matching circuit coupled to the input of the second filter circuit; and a frequency shifting circuit coupled between the second filter circuit and the second input of the signal combiner. The first filter circuit may be a first low-pass to band-pass conversion filter, and the second filter circuit may be a second low-pass to band-pass conversion filter. The circuit may further include a control circuit configured to provide the target impedance to the antenna in a first mode, in a second mode different from the first mode, and in a third mode different from the first and second modes.

[0006] One aspect of this disclosure provides a circuit comprising: a first impedance matching circuit configured to receive a radio frequency (RF) signal; a second impedance matching circuit configured to receive the RF signal; and a combiner having a first input coupled to the first impedance matching circuit and a second input coupled to the second impedance matching circuit. The first input of the combiner may be configured to receive a first signal associated with a first frequency band, and the second input of the combiner may be configured to receive a second signal associated with a second frequency band, the second frequency band being different from the first frequency band. The circuit may further include: a first low-pass to band-pass conversion filter coupled between the first impedance matching circuit and the first input of the combiner; and a second low-pass to band-pass conversion filter coupled between the second impedance matching circuit and the second input of the combiner.

[0007] One aspect of this disclosure provides a circuit comprising: a first switchable matching circuit selectively coupled to an antenna; a second switchable matching circuit selectively coupled to the antenna; a first active filter coupled to the first switchable matching circuit; a second active filter coupled to the second switchable matching circuit; a signal combiner having a first terminal coupled to the first active filter, a second terminal coupled to the second active filter, and a third terminal; and a radio frequency amplifier coupled to the third terminal of the signal combiner. Attached Figure Description

[0008] Figure 1 These are illustrations of exemplary electronic devices with wireless circuitry according to some implementation schemes.

[0009] Figure 2 This is a diagram of an exemplary wireless circuit with an RF amplifier and a filter, according to some implementation schemes.

[0010] Figure 3 This is a diagram of a receiver path that includes an active tunable multiband filter circuit, based on some implementation schemes.

[0011] Figure 4 This is an illustration of an exemplary embodiment of an active tunable multiband filter circuit coupled to an RF amplifier, according to some implementation schemes.

[0012] Figure 5 It is a diagram illustrating the transfer functions of various filters based on some implementation schemes.

[0013] Figure 6This is a circuit diagram of an exemplary low-pass to band-pass converter filter based on some implementation schemes.

[0014] Figure 7 This illustrates the operation according to some implementation schemes. Figures 1 to 6 A table showing the various states of the type of wireless circuit shown.

[0015] Figure 8 It is based on some implementation schemes for operation Figures 1 to 7 A flowchart illustrating the steps of a wireless circuit of the type shown. Detailed Implementation

[0016] Electronic devices, such as Figure 1 The device 10 may include wireless circuitry. This wireless circuitry may include multiple filter paths coupled between the antenna and a single receiving path. These multiple filter paths may include multiple switchable matching circuits, multiple low-pass to band-pass conversion filters, and combiner circuitry. A first filter among these filters may be configured to output a signal in a first frequency band or frequency range, while a second filter among these filters may be configured to output a signal in a second frequency band or frequency range. These multiple filter paths may be operable in at least a first mode, a second mode, and a third mode, in which only the first matching circuit and the first filter in the matching circuitry are activated during the first mode, only the second matching circuit and the second filter in the matching circuitry are activated during the second mode, and all of the first and second matching circuits, as well as the first and second filters, are activated during the third mode. The impedance seen by the antenna may be the same in all three modes. By configuring and operating in this way, radio frequency signals received by the antenna via multiple radio frequency bands can be combined into a single receiving path, thereby significantly reducing the cost of the corresponding transceiver design.

[0017] Figure 1 The electronic device 10 may be: a computing device, such as a laptop computer, desktop computer, computer monitor containing an embedded computer, tablet computer, cellular phone, media player, or other handheld or portable electronic device; a smaller device, such as a wristwatch, a wristband, a headset or handset, a device embedded in glasses; or other equipment worn on a user's head; or other wearable or micro-devices, televisions, computer monitors without an embedded computer, gaming devices, navigation devices, embedded systems (such as systems in which electronic equipment with a display is installed in a kiosk or vehicle), voice-controlled speakers connected to the wireless Internet, home entertainment devices, remote control devices, game controllers, peripheral user input devices, wireless base stations or access points, equipment that enables the functions of two or more of these devices; or other electronic equipment.

[0018] like Figure 1 As shown in the functional block diagram, device 10 may include components located on or within an electronic device housing, such as housing 12. Housing 12 (sometimes referred to as a shell) may be formed of plastic, glass, ceramic, fiber composite material, metal (e.g., stainless steel, aluminum, metal alloys, etc.), other suitable materials, or combinations thereof. In some embodiments, housing 12 may be partially or entirely formed of dielectric or other low-conductivity materials (e.g., glass, ceramic, plastic, sapphire, etc.). In other embodiments, housing 12, or at least some of the structures constituting housing 12, may be formed of metallic elements.

[0019] Device 10 may include control circuitry 14. Control circuitry 14 may include storage devices, such as storage circuitry 16. Storage circuitry 16 may include hard disk drive storage devices, non-volatile memory (e.g., flash memory configured to form a solid-state drive or other electrically programmable read-only memory), volatile memory (e.g., static random access memory or dynamic random access memory), etc. Storage circuitry 16 may include storage devices integrated within device 10, and / or removable storage media.

[0020] 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 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 a non-transitory (tangible) computer-readable storage medium storing software code). This software code may sometimes be referred to as program instructions, software, data, commands, or code. The software code stored on storage circuitry 16 may be executed by processing circuitry 18.

[0021] Control circuitry 14 can be used to run software on device 10, such as satellite navigation applications, internet browsing applications, Voice over Internet Protocol (VoIP) telephone calling applications, email applications, media playback applications, operating system functions, etc. To support interaction with external equipment, control circuitry 14 can be used to implement communication protocols. Communication protocols that can be implemented using control circuitry 14 include: Internet Protocol, Wireless Local Area Network (WLAN) protocols (e.g., IEEE 802.11 protocol—sometimes referred to as...). Protocols for other short-range wireless communication links, such as This protocol may be any of the following: wireless personal area network (WPAN) protocols, IEEE 802.11ad protocols (e.g., ultra-wideband protocols), cellular phone protocols (e.g., 3G, 4G (LTE), 5G, etc.), antenna diversity protocols, satellite navigation system protocols (e.g., Global Positioning System (GPS), Global Navigation Satellite System (GLONASS), etc.), antenna-based spatial ranging protocols (e.g., radio detection and ranging (RADAR) protocols for signals transmitted at millimeter and centimeter wave frequencies or other desired distance detection protocols), or any other desired communication protocol. Each communication protocol may be associated with a corresponding radio access technology (RAT), which specifies the physical connection method used to implement the protocol.

[0022] 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 (e.g., touch-sensitive displays and / or force-sensitive displays), light-emitting components such as displays without touch sensor capability, buttons (mechanical, capacitive, optical, etc.), scroll wheels, touchpads, keypads, 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 for detecting motion), capacitive 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 touchpads, mice and joysticks, and other input-output devices may be coupled to device 10 via wired or wireless connections (e.g., some of the input-output devices 22 may be peripherals coupled to the main processing unit or other parts of device 10 via wired or wireless links).

[0023] Input-output circuitry 20 may include wireless circuitry 24 to support wireless communication. Wireless circuitry 24 (sometimes referred to herein as wireless communication circuitry 24) may include one or more antennas. Wireless circuitry 24 may also include baseband processor circuitry, transceiver circuitry, amplifier circuitry, filter circuitry, switching circuitry, RF transmission lines, and / or any other circuitry for transmitting and / or receiving RF signals using antennas.

[0024] Wireless circuit 24 can transmit and / or receive radio frequency signals within a corresponding frequency band of a radio frequency (sometimes referred to herein as a communication band or simply a "band"). The frequency band processed by wireless circuit 24 may include a wireless local area network (WLAN) band (e.g., (IEEE 802.11) or other WLAN communication bands, such as the 2.4 GHz WLAN band (e.g., 2400 MHz to 2480 MHz), the 5 GHz WLAN band (e.g., 5180 MHz to 5825 MHz), 6E band (e.g., 5925MHz to 7125MHz) and / or others Frequency bands (e.g., 1875MHz to 5160MHz); Wireless Personal Area Network (WPAN) frequency bands such as 2.4GHz Frequency bands or other WPAN communication bands; cellular telephone bands (e.g., bands from about 600 MHz to about 5 GHz, 3G bands, 4G LTE bands, 5G NR frequency range 1 (FR1) band below 10 GHz, 5G NR frequency range 2 (FR2) band between 20 GHz and 60 GHz, etc.); other centimeter or millimeter wave bands between 10 GHz and 300 GHz; near-field communication bands (e.g., 13.56 MHz); satellite navigation bands (e.g., GPS bands from 1565 MHz to 1610 MHz, Global Navigation Satellite System (GLONASS) bands, BeiDou Navigation Satellite System (BDS) bands, etc.); ultra-wideband (UWB) bands operating under the IEEE 802.15.4 protocol and / or other ultra-wideband communication protocols; communication bands under the 3GPP wireless communication standard family; communication bands under the IEEE 802.XX standard family, and / or any other desired bands of interest.

[0025] Figure 2 This is a diagram showing exemplary components within wireless circuit 24. (Example...) Figure 2 As shown, wireless circuitry 24 may include processing circuitry (such as processing circuitry 26), radio frequency (RF) transceiver circuitry (such as RF transceiver 28), RF front-end circuitry (such as RF front-end module (FEM) 40), and antenna 42. Processing circuitry 26 may include one or more baseband processors, application processors, general-purpose processors, microprocessors, microcontrollers, digital signal processors, host processors, dedicated signal processing hardware, or other types of processors. Processing circuitry 26 may be coupled to transceiver 28 via path 34. Transceiver 28 may be coupled to antenna 42 via RF transmission line path 36. RF front-end module 40 may be disposed on RF transmission line path 36 between transceiver 28 and antenna 42.

[0026] exist Figure 2In the example, for clarity, wireless circuit 24 is illustrated as including only one instance of processing circuitry 26, a single transceiver 28, a single front-end module 40, and a single antenna 42. Generally, wireless circuit 24 may include any desired number of processing circuitry 26, any desired number of transceivers 28, any desired number of front-end modules 40, and any desired number of antennas 42. Processing circuitry 26 may be coupled to one or more transceivers 28 via corresponding paths 34. Each transceiver 28 may include transmitter circuitry 30 configured to output uplink signals to antenna 42, may include receiver circuitry 32 configured to receive downlink signals from antenna 42, and may be coupled to one or more antennas 42 via corresponding RF transmit line paths 36. Each RF transmit line path 36 may have a corresponding front-end module 40 disposed thereon. If desired, two or more front-end modules 40 may be disposed on the same RF transmit line path 36. If desired, one or more RF transmit line paths 36 in wireless circuit 24 may be implemented without any front-end modules disposed thereon.

[0027] The RF transmit line path 36 may be coupled to an antenna feed section on the antenna 42. The antenna feed section may, for example, include a positive antenna feed terminal and a ground antenna feed terminal. The RF transmit line path 36 may have a positive transmit line signal path coupled to the positive antenna feed terminal on the antenna 42. The RF transmit line path 36 may have a ground transmit line signal path coupled to the ground antenna feed terminal on the antenna 42. This example is merely illustrative, and in general, the antenna 42 may be fed using any desired antenna feeding scheme. If desired, the antenna 42 may have multiple antenna feed sections coupled to one or more RF transmit line paths 36.

[0028] RF transmission path 36 may include a means for communication with device 10 ( Figure 1 The transmitting lines in device 10 route the radio frequency antenna signals within the device. The transmitting lines in device 10 may include coaxial cables, microstrip transmitting lines, stripline transmitting lines, edge-coupled microstrip transmitting lines, edge-coupled stripline transmitting lines, and transmitting lines formed by combinations of these types of transmitting lines. The transmitting lines in device 10 (such as the transmitting lines in radio frequency transmitting line path 36) may be integrated into rigid and / or flexible printed circuit boards.

[0029] During wireless transmission, processor 26 can provide a transmit signal (e.g., a digital or baseband signal) to transceiver 28 via path 34. Transceiver 28 may also include circuitry for converting the transmit (baseband) signal received from processor 26 into a corresponding radio frequency (RF) signal. For example, transceiver circuitry 28 may include mixer circuitry for up-converting (or modulating) the transmit (baseband) signal to RF before transmission via antenna 42. The processor 26 communicates with transceiver 28 in this manner. Figure 2 The examples provided are merely illustrative. Generally, transceiver 28 can communicate with a baseband processor, application processor, general-purpose processor, microcontroller, microprocessor, or one or more processors within circuit 18. Transceiver circuit 28 may also include digital-to-analog converter (DAC) circuitry and / or analog-to-digital converter (ADC) circuitry for converting signals between the digital and analog domains. Transceiver 28 can transmit radio frequency (RF) signals via transmitter (TX) 30 through RF transmission line path 36 and front-end module 40 via antenna 42. Antenna 42 can transmit the RF signal to external wireless equipment by radiating it into free space.

[0030] During wireless reception, antenna 42 can receive radio frequency (RF) signals from external wireless equipment. The received RF signals can be transmitted to transceiver 28 via RF transmission path 36 and front-end module 40. Transceiver 28 may include circuitry, such as receiver (RX) 32, for receiving signals from front-end module 40 and for converting the received RF signals into corresponding baseband signals. For example, transceiver 28 may include mixer circuitry for down-converting (or demodulating) the received RF signals to baseband frequencies before transmitting the received signals via path 34 to processor 26.

[0031] Front-end module (FEM) 40 may include radio frequency front-end circuitry that operates on radio frequency signals transmitted (transmitted and / or received) via radio frequency transmit line path 36. For example, FEM 40 may include front-end module (FEM) components such as radio frequency filter circuitry 44 (e.g., low-pass filter, high-pass filter, notch filter, band-pass filter, multiplexing circuitry, duplexer circuitry, antenna common circuitry, triplexer circuitry, etc.), switching circuitry 46 (e.g., one or more radio frequency switches), radio frequency amplifier circuitry 48 (e.g., one or more power amplifier circuitry 50 and / or one or more low-noise amplifier circuitry 52), impedance matching circuitry (e.g., circuitry that helps match the impedance of antenna 42 with the impedance of radio frequency transmit line 36), antenna tuning circuitry (e.g., a network of capacitors, resistors, inductors, and / or switches that adjust the frequency response of antenna 42), 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 antenna 42. Each of the front-end module components can be mounted on a common (shared) substrate, such as a rigid printed circuit board substrate or a flexible printed circuit board substrate. If desired, the various front-end module components can also be integrated into a single integrated circuit chip. If desired, amplifier circuitry 48 and / or other components in front-end 40 (such as filter circuitry 44) can also be implemented as part of transceiver circuitry 28.

[0032] Filter circuitry 44, switching circuitry 46, amplifier circuitry 48, and other circuitry may be disposed along RF transmission line path 36, may be incorporated into FEM 40, and / or may be incorporated into antenna 42 (e.g., to support antenna tuning, to support operation in a desired frequency band, etc.). These components (sometimes referred to herein as antenna tuning components) may be adjusted (e.g., using control circuitry 14) to regulate the frequency response and wireless performance of antenna 42 over time.

[0033] Transceiver 28 may be separate from front-end module 40. For example, transceiver 28 may be formed on another substrate such as the main logic board of device 10, a rigid printed circuit board, or a flexible printed circuit that is not part of front-end module 40. Although for clarity, in Figure 1In the example, control circuitry 14 is shown separate from wireless circuitry 24, but wireless circuitry 24 may include processing circuitry and / or storage circuitry, the processing circuitry forming part of processing circuitry 18 and the storage circuitry forming 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, portions of processor 26 and / or transceiver 28 (e.g., a host processor on transceiver 28) may form part of control circuitry 14. Control circuitry 14 (e.g., portions of control circuitry 14 formed on processor 26, portions of control circuitry 14 formed on transceiver 28, and / or portions of control circuitry 14 separate from wireless circuitry 24) may provide control signals (e.g., via one or more control paths in device 10) to control the operation of front-end module 40.

[0034] Transceiver circuitry 28 may include processing WLAN communication bands (e.g., (IEEE 802.11) or other WLAN communication bands, such as the 2.4 GHz WLAN band (e.g., 2400 MHz to 2480 MHz), the 5 GHz WLAN band (e.g., 5180 MHz to 5825 MHz), 6E band (e.g., 5925MHz to 7125MHz) and / or others Wireless LAN transceiver circuitry covering a frequency band (e.g., 1875MHz to 5160MHz); handling 2.4GHz. Wireless personal area network transceiver circuits for frequency bands or other WPAN communication bands; cellular phone transceiver circuits for processing cellular phone frequency bands (e.g., bands from about 600 MHz to about 5 GHz, 3G bands, 4G LTE bands, 5G New Radio Frequency Range 1 (FR1) band below 10 GHz, 5G New Radio Frequency Range 2 (FR2) band between 20 GHz and 60 GHz, etc.); near field communication (NFC) transceiver circuits for processing near field communication frequency bands (e.g., 13.56 MHz); satellite navigation receiver circuits for processing satellite navigation frequency bands (e.g., GPS band from 1565 MHz to 1610 MHz, Global Navigation Satellite System (GLONASS) band, BeiDou Navigation Satellite System (BDS) band, etc.); ultra-wideband (UWB) transceiver circuits for processing communications using the IEEE 802.15.4 protocol and / or other ultra-wideband communication protocols; and / or any other desired radio frequency transceiver circuits for covering any other desired communication frequency bands of interest.

[0035] Wireless circuit 24 may include one or more antennas, such as antenna 42. Antenna 42 can be formed using any desired antenna structure. For example, antenna 42 may be an antenna with a resonant element, formed from a loop antenna structure, patch antenna structure, inverted F-shaped antenna structure, slot antenna structure, planar inverted F-shaped antenna structure, helical antenna structure, monopole antenna, dipole, a combination of these designs, etc. Two or more antennas 42 may be arranged in one or more phased antenna arrays (e.g., for transmitting radio frequency signals at millimeter-wave frequencies). Parasitic elements may be included in antenna 42 to adjust antenna performance. Antenna 42 may be provided with a conductive cavity that supports the antenna resonant element of antenna 42 (e.g., antenna 42 may be a cavity-backed antenna, such as a cavity-backed slot antenna).

[0036] Figure 3 This is a diagram of the receiving path within wireless circuit 24. (See diagram for example.) Figure 3 As shown, wireless circuit 24 may include filter circuitry, such as filter circuitry 44 coupled to one or more antennas via at least a first signal path 43-1 and a second signal path 43-2. ​​Filter circuitry 44 may be an "active" filter, meaning a filter circuitry that may include not only passive electronic components but also active electronic components (such as transistors). Filter circuitry 44 is also tunable, meaning it can operate in multiple different modes. Tunable filter circuitry 44 may be able to operate in two or more modes, three or more modes, four or more modes, or other suitable number of operating modes. Filter circuitry 44 may also be a "multi-band" filter, meaning it can combine or merge signals from more than one radio frequency band (e.g., combine signals from different frequency ranges). Multi-band filter circuitry 44 may be able to operate to merge radio frequency signals from two or more bands, three or more bands, four or more bands, or other suitable number of bands. Therefore, filter circuitry 44 may sometimes be referred to as an active tunable multi-band filter circuitry 44.

[0037] The active tunable multiband filter circuit 44 can be coupled to an RF amplifier. Figure 3 In this example, filter circuit 44 may have an output coupled to RF amplifier 52 (e.g., a low-noise amplifier in the receive path). Filter circuit 44 and amplifier 52 may be part of front-end module 40. Front-end module 40 may optionally include... Figure 3Other front-end components not shown (e.g., module 40 may include one or more components coupled between antenna 42 and filter 44, one or more components coupled between filter 44 and amplifier 52, and one or more components coupled at the output of amplifier 52). It is technically advantageous to use only a single receive amplifier 52 to receive the multi-band signals combined at filter circuit 44 and to simplify subsequent transceiver design. Amplifier 52 may have an output coupled to a corresponding receiver 32. Receiver 32 may be part of transceiver 28 (see also...). Figure 2 Receiver 32 may include, for example, one or more down-converters (e.g., mixers) for demodulating the received radio frequency signals and one or more data converters for converting analog radio frequency signals into digital signals.

[0038] Figure 4 This is a diagram illustrating an exemplary implementation of an active tunable multiband filter circuit 44. (See diagram for details.) Figure 4 As shown, the filter circuit 44 may include a first switchable matching circuit 60-1 (sometimes referred to herein as "M1"), a second switchable matching circuit 60-2 (sometimes referred to herein as "M2"), a first filter 62-1 (sometimes referred to herein as "F1"), a second filter 62-2 (sometimes referred to herein as "F2"), and signal combining circuitry such as a combiner 66. The first switchable matching circuit 60-1 may be an impedance matching circuit that is selectively coupled to the antenna 42 via signal path 43-1 and a first switch 68-1, and may be configured to provide one or more impedance values ​​that match the impedance of the antenna 42. Switch 68-1 may be activated to connect the matching circuit 60-1 to the antenna signal path 43-1, and may be deactivated to disconnect the matching circuit 60-1 from the antenna 42.

[0039] The term "activation" in this document refers to or is defined as the action of placing the switch in a "conducting" or low-impedance state, such that the two terminals of the switch are electrically connected to conduct current. Activating a switch may sometimes be referred to as turning on or closing a switch. The term "deactivation" in this document refers to or is defined as the action of placing the switch in a "de-off" or high-impedance state, such that the two terminals of the switch / transistor are electrically disconnected with minimal leakage current. Deactivating a switch may sometimes be referred to as turning off or opening a switch.

[0040] Similarly, the second switchable matching circuit 60-2 can be an impedance matching circuit that can be selectively coupled to the antenna 42 via signal path 43-2 and a second switch 68-2, and can be configured to provide one or more impedance values ​​that match the antenna 42. Switch 68-2 can be activated to connect matching circuit 60-2 to the antenna signal path 43-2, and can be deactivated to disconnect matching circuit 60-2 from the antenna 42. As an example, each of impedance matching circuits 60-1 and 60-2 can be configured, individually, to provide impedances of the following magnitudes: 50 ohms, 100 ohms, 75 ohms, 50 to 100 ohms, less than 50 ohms, greater than 50 ohms, less than 100 ohms, greater than 100 ohms, and / or other impedance values. The states of switches 68-1 and 68-2, and the amount of impedance provided by matching circuits 60-1 and 60-2, can be adjusted based on control signals transmitted from transceiver 28 via path 74. The transceiver 28 may include one or more control circuits configured to output control signals for selectively activating and deactivating switches 68-1 and 68-2, and selectively configuring each of the matching circuits 60-1 and 60-2 to provide the same or different impedance values.

[0041] The first filter 62-1 may have an input coupled to the switchable impedance matching circuit 60-1. Filter 62-1 may be a low-pass to passband conversion filter (e.g., a filter configured to provide low-pass to band-pass conversion). Filter 62-1 may, for example, be implemented as a first N-path filter. Filter 62-1 may be configured to provide... Figure 5 The filter response or transfer function is illustrated in the example. Figure 5 The functional relationship between signal power and frequency was plotted. Figure 5 In the example, the radio frequency signal can be transmitted in a first frequency band (“Band_A”) centered at frequency f_txA. The radio frequency signal associated with Band_A can be received at frequency f_rxA, which is offset from frequency f_txA. Although in Figure 5 In the example, the frequency f_rxA is shown as greater than the frequency f_txA, but the frequency f_rxA may alternatively be less than the frequency f_txA.

[0042] It may be desirable to reduce / attenuate the transmitted signal power at frequency f_txA before the antenna signal can be fed into the receiving path. Therefore, filter 62-1 can be configured to provide the filter transfer function exemplified by filter response 80-1. Figure 5As shown, the filter response 80-1 can have a passband centered at frequency f_rxA, while suppressing transmitted signals at nearby frequencies f_txA (e.g., suppressing them by 30 dB or more). (See reference again) Figure 4 Therefore, filter 62-1 can output the received signal associated with Band_A, which is sometimes referred to as the first frequency or the first frequency range. It should be understood that the filter is not a perfect circuit component, and therefore filter 62-1 may output residual (minor) signals outside the first frequency range.

[0043] Similarly, the second filter 62-2 may have an input coupled to the switchable impedance matching circuit 60-2. Filter 62-2 may be a low-pass to passband conversion filter (e.g., a filter configured to provide low-pass to band-pass conversion). Filter 62-2 may, for example, be implemented as a second N-path filter. Filter 62-2 may be configured to provide... Figure 5 The filter response or transfer function is also illustrated in the example. Figure 5 In the example, the radio frequency signal can be transmitted additionally in a second frequency band (“Band_B”) centered at frequency f_txB. The radio frequency signal associated with Band_B can be received at frequency f_rxB, which is offset from frequency f_txB. Although in Figure 5 In the example, the frequency f_rxB is shown as greater than the frequency f_txB, but the frequency f_rxB can optionally be less than the frequency f_txB. Furthermore, although in Figure 5 In the example, frequencies f_txB and f_rxB are shown as being greater than frequencies f_txA and f_rxA, but frequencies f_txB and f_rxB may alternatively be less than frequencies f_txA and f_rxA.

[0044] It may be desirable to reduce / attenuate the transmitted signal power at frequency f_txB before the antenna signal can be fed into the receiving path. Therefore, filter 62-2 can be configured to provide the filter transfer function exemplified by filter response 80-2. Figure 5 As shown, the filter response 80-2 can have a passband centered at frequency f_rxB, while suppressing transmitted signals at nearby frequencies f_txB (e.g., suppressing them by 30dB or more). (See reference again) Figure 4 Therefore, filter 62-2 can output the received signal associated with Band_B, which is sometimes also referred to as the second frequency (different from the first frequency) or the second frequency range (different from the first frequency range). Band_A and Band_B can be, for example, non-overlapping frequency ranges. It should be understood that the filter is not a perfect circuit component, and therefore filter 62-2 may output residual (minor) signals outside the second frequency range.

[0045] According to some implementation schemes, filters 62-1 and 62-2 can be implemented as N-path filters. An "N-path filter" can refer to, and is defined herein, as an active filter circuit having multiple switchable paths (see, for example...). Figure 6 ).like Figure 6 As shown, the N-path filter 62 may include an input terminal IN, an output terminal OUT, one or more passive components 100 series-coupled between the input and output terminals, and N parallel paths 102-1, 102-2, ..., 102-N. The number N can be an integer greater than 2, 2 to 10, 10 to 20, 20 to 30, 30 to 50, 50 to 100, greater than 100, 100 to 1000, greater than 1000, or other integer values. Each of the N parallel paths 102 may include one or more passive electronic components 106 series-coupled with a switch 104. Activating the switch 104 switches to the use of the corresponding component 106, while deactivating the switch 104 switches to the non-use of the corresponding component 106. The various passive components 100 and 106 may represent one or more capacitors, one or more inductors, one or more resistors, other passive components, and / or optionally active electronic components. Figure 6 The N-path filter shown is exemplary. Filters 62-1 and 62-2 can be implemented as other types of bandpass filter circuits if desired.

[0046] Return to reference again Figure 4 Combiner 66 may have a first input coupled to filter 62-1 and a second input coupled to filter 62-2. The first input of combiner 66 may be configured to receive an RF signal in Band_A, while the second input of combiner 66 may be configured to receive an RF signal in Band_B. Optionally, if desired, frequency shift circuitry 64 may be coupled between filter 62-2 and the second input of combiner 66, wherein frequency shifter 64 is configured to provide a frequency shift amount for reducing any frequency gap between the two receiving frequency bands Band_A and Band_B. Frequency shifter 64 may, for example, be configured to shift the received signal from Band_B to a shifted frequency range Band_B' closer to Band_A. In other words, frequency shifter 64 may be configured to move the two frequency bands Band_A and Band_B closer to each other. Doing so is technically advantageous and beneficial for minimizing the bandwidth requirements of subsequent receivers. The frequency shifter 64 is coupled between the filter 62-2 and the second input terminal of the combiner 66. Figure 4 The example is illustrative. Alternatively, frequency shifter 64 may be coupled between filter 62-1 and the first input of combiner 66.

[0047] Assuming both receive paths are active, combiner 66 can be configured to combine or merge the radio frequency signals received at its two inputs into (e.g., combine signals from two different radio frequency bands or ranges into) a single multi-band signal. In other words, combiner 66 can direct two filtered bands to the same output signal line. However, if only the first receive path is active (e.g., if only switchable matching circuit 60-1 is connected to antenna 42, while switchable matching circuit 60-2 is disconnected from antenna 42), combiner 66 will simply pass the signal received at its first input to its output. Conversely, if only the second receive path is active (e.g., if only switchable matching circuit 60-2 is connected to antenna 42, while switchable matching circuit 60-1 is disconnected from antenna 42), combiner 66 will simply pass the signal received at its second input to its output.

[0048] Combiner 66 may have an output coupled to a single receive RF amplifier 52. Amplifier 52 may be configured to amplify the received signal and output the corresponding amplified signal to transceiver 28. If desired, wireless circuitry 24 may optionally include one or more components (not shown) coupled between amplifier 52 and transceiver 28. Transceiver 28 may include receiver circuitry, such as a wideband (WB) receiver 70. Wideband receiver 70 may be configured with a bandwidth wide enough to accommodate two filtered frequency bands / ranges (e.g., receiver 70 has a bandwidth covering both Band_A and optionally a shifted Band_B'). Wideband receiver 70 may be configured to downconvert the combined signal from RF to a baseband frequency or an intermediate frequency (e.g., a frequency between RF and baseband frequencies). Wideband receiver 70 may include one or more downconversion mixers, one or more filters, one or more analog-to-digital converters, etc.

[0049] The wideband receiver 70 may have outputs coupled to a first mixer and filter circuit 72-1 and a second mixer and filter circuit 72-2. The first mixer and filter circuit 72-1 may have a narrower bandwidth than the wideband receiver 70. Circuit 72-1 may include a first digital filter and a first mixer configured to demodulate a signal at the input or output of the first digital filter (e.g., the first mixer may be coupled before or after the first digital filter). Therefore, the first mixer and filter circuit 72-1 may be configured to output a corresponding first digital baseband signal BB_A down-converted from Band_A. The second mixer and filter circuit 72-2 may have a narrower bandwidth than the wideband receiver 70. Circuit 72-2 may include a second digital filter and a second mixer configured to demodulate a signal at the input or output of a second digital filter (e.g., the second mixer may be coupled before or after the second digital filter). Therefore, the second mixer and filter circuit 72-2 can be configured to output a corresponding second digital baseband signal BB_B, down-converted from Band_B or optionally Band_B' (if frequency shifter 64 is used). The baseband signals BB_A and BB_B can be transmitted to the processing circuit 26 (see, for example...). Figure 2 (This is for subsequent processing.)

[0050] Figure 7 It is used for operation combination Figures 1 to 6 A table describing the various states of the type of wireless circuit 24. (See table below.) Figure 7 As shown, wireless circuit 24 can be configured to operate in at least three or more modes. In a first mode, wireless circuit 24 can be configured to process only signals in Band_A (e.g., signals at a first frequency or within a first frequency range). In the first mode, a first low-pass to band-pass conversion filter 62-1 can be activated, while a second low-pass to band-pass conversion filter 62-2 can be deactivated. In the first mode, a first matching circuit 60-1 can be switched to use, while a second matching circuit 60-2 can be switched to non-use (e.g., disconnected from the antenna). For example, the activated matching circuit 60-1 can be configured to provide a 50-ohm impedance to the connected antenna.

[0051] In a second mode, different from the first mode, wireless circuit 24 can be configured to process only signals in Band_B or optionally Band_B' (e.g., signals at a second frequency or within a second frequency range). In the second mode, the second low-pass to band-pass conversion filter 62-2 can be activated, while the first low-pass to band-pass conversion filter 62-1 is deactivated. In the second mode, the second matching circuit 60-2 can be switched to use, while the first matching circuit 60-1 can be switched to non-use (e.g., disconnected from the antenna). For example, the activated matching circuit 60-2 can be configured to provide a 50-ohm impedance to the connected antenna.

[0052] In a third mode, different from the first and second modes, the wireless circuit 24 can be configured to process signals from both Band_A and Band_B (or optionally Band_B'). In the third mode, the first low-pass to band-pass conversion filter 62-1 and the second low-pass to band-pass conversion filter 62-2 can be activated simultaneously. In the third mode, the first matching circuit 60-1 and the second matching circuit 60-2 can be switched to use and connected to the antenna. For example, matching circuits 60-1 and 60-2 can each be configured to provide a 100-ohm impedance, thus providing a combined 50-ohm impedance to the connected antenna. Operating in this way, for each of the different modes, the wireless circuit can present a constant target impedance (e.g., 50 ohms, as an example) to the antenna, thereby providing optimal power delivery to the receive path. The wireless circuit is capable of operating in at least three different modes. Figure 7 The examples are illustrative. If desired, the wireless circuitry can be configured to operate in four or more modes, five or more modes, five to ten different modes, or more than ten modes to receive signals associated with different groups of frequencies.

[0053] Figure 8 It is used for operation combination Figures 1 to 7 A flowchart illustrating exemplary steps of the described type of wireless circuit 24. During operation of block 200, switchable matching circuits 60-1 and 60-2 can be selectively switched into use based on whether Band_A and / or Band_B are active. This can be achieved via transceiver 28, processing circuit 26 (see...). Figure 2The switchable matching circuits 60-1 and 60-2 are adjusted by control signals output from other control circuits within the electronic device 10. If only Band_A is active, only switchable matching circuit 60-1 will be switched to use (e.g., by activating switch 68-1 and deactivating switch 68-2). If only Band_B is active, only switchable matching circuit 60-2 will be switched to use (e.g., by activating switch 68-2 and deactivating switch 68-1). If both Band_A and Band_B are active, both switchable impedance matching circuits 60-1 and 60-2 can be switched to use (e.g., by activating both switches 68-1 and 68-2).

[0054] During the operation of block 202, the first low-pass to band-pass conversion filter 62-1 can be configured to filter the received signal to produce a corresponding first filtered signal (e.g., the filtered signal in Band_A). The operation of block 202 can... Figure 7 It is executed in either the first or third mode shown. When operating the wireless circuit in the second mode, the operation of box 202 can be bypassed or omitted because the first receiving path will be switched off.

[0055] During the operation of block 204, the second low-pass to band-pass conversion filter 62-2 can be configured to filter the received signal to produce a corresponding second filtered signal (e.g., the filtered signal in Band_B). The operation of block 204 can... Figure 7 The operation is performed in either the second or third mode shown. When the wireless circuit is operated in the first mode, the operation of box 204 can be bypassed or omitted because the second receiving path will be switched off. Although the operation of box 204 is shown to occur after box 202, the operations of boxes 202 and 204 can occur in parallel (simultaneously) when the wireless circuit is operated in the third mode.

[0056] During the operation of block 206, frequency shifter 64 may optionally shift the frequency of the second filtered signal. Frequency shifter 64 may be configured to shift the second filtered signal from Band_B to Band_B', where Band_B' is closer to Band_A than Band_B. Doing so reduces the bandwidth requirements of receiver 70, thereby simplifying receiver design, reducing cost, and reducing power consumption. The operation of block 206 may be omitted.

[0057] During operation of block 208, combiner 66 can be configured to combine or merge multi-band signals received from one or more receive paths. In a first mode, combiner 66 may receive only the Band_A signal from the first filter 62-1. In a second mode, combiner 66 may receive only the Band_B (or optionally Band_B') signal from the second filter 62-2. In a third mode, combiner 66 may receive both the Band_A and Band_B (or optionally Band_B') signals from both the first filter 62-1 and the second filter 62-2. Combiner 66 may output the signal to receive RF amplifier 52.

[0058] During operation of block 210, RF amplifier 52 can be configured to amplify the signal received from combiner 66. Amplifier 52 can output the corresponding amplified RF signal to transceiver 28 via a single (only one) receive path.

[0059] During operation of block 212, the wideband receiver 70 can be configured to down-convert, filter, and optionally convert the amplified signal to a corresponding baseband signal. During operation of block 214, circuit 72-1 can be configured to further filter and / or demodulate the baseband signal to generate a corresponding signal associated with Band_A. During operation of block 216, circuit 72-2 can be configured to further filter and / or demodulate the baseband signal to generate a corresponding signal associated with Band_B. Although Figure 8 The diagram shows that box 216 occurs after box 214, but the operation of box 216 can occur in parallel (simultaneously) with the operation of box 214. Since the Band_A signal is absent in the second mode, the operation of box 214 can be omitted in the second mode. Since the Band_B signal is absent in the first mode, the operation of box 216 can be omitted in the first mode.

[0060] Figure 8 The operations described are illustrative. In some embodiments, one or more of the described operations may be modified, replaced, or omitted. In some embodiments, one or more of the described operations may be performed in parallel. In some embodiments, additional processes may be added or inserted between the described operations. If necessary, the order of certain operations may be reversed or changed, and / or the timing of the described operations may be adjusted so that they occur at slightly different times. In some embodiments, the described operations may be distributed across a larger system.

[0061] The above text combined Figures 1 to 8The described methods and operations can be performed by components of device 10 using software, firmware, and / or hardware (e.g., dedicated circuitry or hardware). Software code for performing these operations may be stored on a non-transitory computer-readable storage medium (e.g., a tangible computer-readable storage medium) stored on one or more components of device 10 (e.g., ...). Figure 1 The storage circuit 16 and / or wireless communication circuit 24). This software code may sometimes be referred to as software, data, instructions, program instructions, or code. Non-transitory computer-readable storage media may include drives, non-volatile memory such as non-volatile random access memory (NVRAM), removable flash drives or other removable media, other types of random access memory, etc. The software stored on the non-transitory computer-readable storage medium may be processed by processing circuitry on one or more components of the device 10 (e.g., processing circuitry 26 in wireless circuitry 24, ...). Figure 1 The processing circuit 26 may be used to execute the processing (such as the processing circuit 18). The processing circuit 26 may include a microprocessor, application processor, digital signal processor, central processing unit (CPU), application-specific integrated circuit with processing circuitry, or other processing circuitry.

[0062] According to one embodiment, a circuit includes: a first filter circuit configured to output a signal in a first frequency range; a second filter circuit configured to output a signal in a second frequency range different from the first frequency range; a signal combiner having a first input coupled to the first filter circuit and a second input coupled to the second filter circuit; and a first switchable matching circuit coupled to the input of the first filter circuit.

[0063] According to another embodiment, the circuit may optionally include a second switchable matching circuit coupled to the input of the second filter circuit.

[0064] According to another embodiment, the first switchable matching circuit may optionally include a first switch that is selectively activated to couple the input of the first filter circuit to the antenna and selectively deactivated to disconnect the input of the first filter circuit from the antenna.

[0065] According to another embodiment, the second switchable matching circuit may optionally include a second switch that is selectively activated to couple the input of the second filter circuit to the antenna, and selectively deactivated to disconnect the input of the second filter circuit from the antenna.

[0066] According to another embodiment, the first switchable matching circuit is optionally configured to provide a plurality of different impedances, and the second switchable matching circuit is optionally configured to provide a plurality of different impedances.

[0067] According to another embodiment, the circuit may optionally include a frequency shift circuit coupled between the second filter circuit and the second input terminal of the signal combiner.

[0068] According to another embodiment, the circuit may optionally include: only one radio frequency amplifier coupled to the output of the signal combiner.

[0069] According to another embodiment, the circuit may optionally include: a radio frequency amplifier coupled to the output of the signal combiner; and a receiver coupled to the output of the radio frequency amplifier.

[0070] According to another embodiment, the circuit may optionally include: a first circuit coupled to the output of the receiver and configured to output a first baseband signal, wherein the first circuit may optionally have a first bandwidth, and the receiver may optionally have a second bandwidth greater than the first bandwidth.

[0071] According to another embodiment, the circuit may optionally include: a second circuit coupled to the output of the receiver and configured to output a second baseband signal, wherein the second circuit may optionally have a third bandwidth that is less than the second bandwidth of the receiver.

[0072] According to another embodiment, the first filter circuit may optionally include a first active filter, and the second filter circuit may optionally include a second active filter.

[0073] According to another embodiment, the first filter circuit may optionally include a first low-pass to band-pass conversion filter, and the second filter circuit may optionally include a second low-pass to band-pass conversion filter.

[0074] According to another embodiment, the first filter circuit may optionally include a first N-path filter, the second filter circuit may optionally include a second N-path filter, and N may optionally be an integer greater than two.

[0075] According to another embodiment, the circuit may optionally include: a first switchable matching circuit coupled to the input of the first filter circuit; a second switchable matching circuit coupled to the input of the second filter circuit; and a control circuit configured to provide the first and second switchable matching circuits to the antenna in a first mode, to provide the target impedance to the antenna in a second mode different from the first mode, and to provide the target impedance to the antenna in a third mode different from the first and second modes.

[0076] According to another embodiment, during the first mode, the first switchable matching circuit is optionally activated while the second switchable matching circuit is deactivated.

[0077] According to another embodiment, during the second mode, the second switchable matching circuit is optionally activated while the first switchable matching circuit is deactivated.

[0078] According to another embodiment, during the third mode, the first switchable matching circuit and the second switchable matching circuit are optionally activated.

[0079] According to one embodiment, a circuit includes: a first impedance matching circuit configured to receive a radio frequency (RF) signal; a second impedance matching circuit configured to receive the RF signal; and a combiner having a first input coupled to the first impedance matching circuit and a second input coupled to the second impedance matching circuit, wherein: the first input of the combiner is configured to receive a first signal associated with a first frequency band, and the second input of the combiner is configured to receive a second signal associated with a second frequency band, the second frequency band being different from the first frequency band.

[0080] According to another embodiment, the circuit may optionally include: a first low-pass to band-pass conversion filter coupled between the first impedance matching circuit and the first input terminal of the combiner; and a second low-pass to band-pass conversion filter coupled between the second impedance matching circuit and the second input terminal of the combiner.

[0081] According to one embodiment, a circuit includes: a first switchable matching circuit selectively coupled to an antenna; a second switchable matching circuit selectively coupled to the antenna; a first active filter coupled to the first switchable matching circuit; a second active filter coupled to the second switchable matching circuit; a signal combiner having a first terminal coupled to the first active filter, a second terminal coupled to the second active filter, and a third terminal; and a radio frequency amplifier coupled to the third terminal of the signal combiner.

[0082] According to one embodiment, a method of operating a wireless circuit includes: outputting a first signal in a first frequency range using a first low-pass to band-pass conversion filter; outputting a second signal in a second frequency range different from the first frequency range using a second low-pass to band-pass conversion filter; and receiving the first signal from the first low-pass to band-pass conversion filter and the second signal from the second low-pass to band-pass conversion filter using a combiner.

[0083] According to another embodiment, the method may optionally include: coupling the first filter to the antenna using a first matching circuit, and coupling the second filter to the antenna using a second matching circuit.

[0084] According to another embodiment, the method may optionally include: activating a first switch of the first matching circuit to couple the first filter to the antenna.

[0085] According to another embodiment, the method may optionally include: deactivating the first switch of the first matching circuit to decouple the first filter from the antenna.

[0086] According to another embodiment, the method may optionally include: activating a second switch of the second matching circuit to couple the second filter to the antenna; and deactivating the second switch of the second matching circuit to decouple the second filter from the antenna.

[0087] According to another embodiment, the method may optionally include: activating the first switch and deactivating the second switch during a first mode; and activating the second switch and deactivating the first switch during a second mode different from the first mode.

[0088] According to another embodiment, the method may optionally include: activating the first switch and the second switch during a third mode that is different from the first mode and the second mode.

[0089] According to another embodiment, the method may optionally include: configuring the first matching circuit to provide a first impedance during the first mode; and configuring the second matching circuit to provide a second impedance equal to the first impedance during the second mode.

[0090] According to another embodiment, the method may optionally include: configuring the first matching circuit to provide a third impedance different from the first impedance during the third mode; and configuring the second matching circuit to provide a fourth impedance equal to the third impedance during the third mode.

[0091] According to another embodiment, the method may optionally include: using a frequency shifter to shift the second signal from the second frequency range to a third frequency range that is closer to the first frequency range.

[0092] According to another embodiment, the method may optionally include: using the combiner to output a signal to only one radio frequency amplifier.

[0093] According to another embodiment, the method may optionally include: using the combiner to output a signal to an RF amplifier; using a receiver circuit having a first bandwidth to receive a signal from the RF amplifier; using a first mixer and filter circuit to receive a signal from the receiver circuit and output a first baseband signal; and using a second mixer and filter circuit to receive a signal from the receiver circuit and output a second baseband signal.

[0094] According to another embodiment, the first mixer and filter circuit may optionally have a second bandwidth less than the first bandwidth, and wherein the second mixer and filter circuit may optionally have a third bandwidth less than the first bandwidth.

[0095] According to one embodiment, a method of operating a wireless circuit includes: during a first mode, configuring a first switchable matching circuit to provide a first impedance to an antenna; during a second mode, configuring a second switchable matching circuit to provide a second impedance to the antenna; and using a combiner to receive a first filtered signal generated based on a signal received through the first switchable matching circuit, and to receive a second filtered signal generated based on a signal received through the second switchable matching circuit.

[0096] According to another embodiment, the method may optionally include: during a third mode, configuring the first switchable matching circuit to provide the antenna with a third impedance greater than the first impedance; and during the third mode, configuring the second switchable matching circuit to provide the antenna with a fourth impedance greater than the second impedance.

[0097] According to another embodiment, the third impedance may optionally be equal to the fourth impedance.

[0098] According to another embodiment, the method may optionally include: outputting the first filtered signal using a first filter coupled to the first switchable matching circuit; and outputting the second filtered signal using a second filter coupled to the second switchable matching circuit.

[0099] According to another embodiment, the first filter may optionally include a first low-pass to band-pass conversion filter, and the second filter may optionally include a second low-pass to band-pass conversion filter.

[0100] According to another embodiment, the method may optionally include: shifting the frequency of the second filtered signal using a frequency shifter coupled between the second filter and the combiner.

[0101] According to one embodiment, a wireless circuit includes: a first matching circuit configured to provide one or more impedance values; a second matching circuit configured to provide one or more impedance values; a first component for filtering a signal from the first matching circuit; a second component for filtering a signal from the second matching circuit; and a third component for combining signals from the first component and the second component.

[0102] The foregoing is merely illustrative and various modifications can be made to the described implementation scheme. The foregoing implementation scheme can be implemented individually or in any combination.

[0103] As is widely recognized, the use of personally identifiable information should comply with privacy policies and practices that are generally accepted to meet or exceed industry or governmental requirements for protecting user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of authorized use should be clearly explained to users.

Claims

1. A circuit, the circuit comprising: A first filter circuit, configured to output a signal in a first frequency range; A second filter circuit is configured to output a signal in a second frequency range that is different from the first frequency range. A signal combiner having a first input terminal coupled to the first filter circuit and a second input terminal coupled to the second filter circuit; and A first switchable matching circuit is coupled to the input of the first filter circuit.

2. The circuit according to claim 1, further comprising: A second switchable matching circuit is coupled to the input of the second filter circuit.

3. The circuit of claim 2, wherein the first switchable matching circuit includes a first switch, the first switch being selectively activated to couple the input terminal of the first filter circuit to the antenna, and selectively deactivated to disconnect the input terminal of the first filter circuit from the antenna.

4. The circuit of claim 3, wherein the second switchable matching circuit includes a second switch that is selectively activated to couple the input of the second filter circuit to the antenna, and selectively deactivated to disconnect the input of the second filter circuit from the antenna.

5. The circuit of claim 2, wherein the first switchable matching circuit is configured to provide a plurality of different impedances, and wherein the second switchable matching circuit is configured to provide a plurality of different impedances.

6. The circuit according to claim 1, further comprising: A frequency shift circuit is coupled between the second filter circuit and the second input terminal of the signal combiner.

7. The circuit according to claim 1, further comprising: There is only one radio frequency amplifier, which is coupled to the output of the signal combiner.

8. The circuit according to claim 1, further comprising: A radio frequency amplifier, which is coupled to the output of the signal combiner; and A receiver is coupled to the output of the radio frequency amplifier.

9. The circuit according to claim 8, further comprising: A first circuit is coupled to the output of the receiver and configured to output a first baseband signal, wherein the first circuit has a first bandwidth, and wherein the receiver has a second bandwidth greater than the first bandwidth.

10. The circuit according to claim 9, further comprising: A second circuit, coupled to the output of the receiver and configured to output a second baseband signal, wherein the second circuit has a third bandwidth that is less than the second bandwidth of the receiver.

11. The circuit of claim 1, wherein the first filter circuit includes a first active filter, and wherein the second filter circuit includes a second active filter.

12. The circuit of claim 1, wherein the first filter circuit includes a first low-pass to band-pass conversion filter, and wherein the second filter circuit includes a second low-pass to band-pass conversion filter.

13. The circuit of claim 1, wherein the first filter circuit includes a first N-path filter, wherein the second filter circuit includes a second N-path filter, and wherein N is an integer greater than two.

14. The circuit according to claim 1, further comprising: A first switchable matching circuit is coupled to the input of the first filter circuit. A second switchable matching circuit is coupled to the input of the second filter circuit. and A control circuit is configured to provide a target impedance to an antenna in a first mode, in a second mode different from the first mode, and in a third mode different from the first and second modes.

15. The circuit of claim 14, wherein during the first mode, the first switchable matching circuit is activated while the second switchable matching circuit is deactivated.

16. The circuit of claim 15, wherein during the second mode, the second switchable matching circuit is activated while the first switchable matching circuit is deactivated.

17. The circuit of claim 16, wherein during the third mode, the first switchable matching circuit and the second switchable matching circuit are activated.

18. A circuit, the circuit comprising: A first impedance matching circuit, configured to receive radio frequency signals; A second impedance matching circuit is configured to receive the radio frequency signal; and A combiner having a first input terminal coupled to the first impedance matching circuit and a second input terminal coupled to the second impedance matching circuit, wherein: The first input of the combiner is configured to receive a first signal associated with a first frequency band; and The second input of the combiner is configured to receive a second signal associated with a second frequency band, which is different from the first frequency band.

19. The circuit of claim 18, further comprising: A first low-pass to band-pass conversion filter is coupled between the first impedance matching circuit and the first input terminal of the combiner. and A second low-pass to band-pass conversion filter is coupled between the second impedance matching circuit and the second input terminal of the combiner.

20. A circuit, the circuit comprising: A first switchable matching circuit is selectively coupled to an antenna; A second switchable matching circuit is selectively coupled to the antenna; A first active filter, the first active filter being coupled to the first switchable matching circuit; The second active filter is coupled to the second switchable matching circuit; A signal combiner having a first terminal coupled to a first active filter, a second terminal coupled to a second active filter, and a third terminal; and A radio frequency amplifier, which is coupled to the third terminal of the signal combiner.

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