High-frequency front-end module with a common filter

Abstract

To provide a high frequency front end module with a common filter.SOLUTION: An RF front end part 310 comprises: at least one power amplifier 602 that amplifies a transmission high frequency signal; one low noise amplifier 604 that receives a reception high frequency signal; an output node connected to an antenna; at least one switch 614 that is selectively connected to at least one power amplifier in a transmission period, and is connected to at least one low noise amplifier in a reception period; at least one transmission filter 610 that is connected to the power amplifier and at least one switch; and at least one reception filter 612 that is connected to the low noise amplifier and the at least one switch.SELECTED DRAWING: Figure 9B

Description

Technical Field

[0001] Cross - Reference to Related Applications All applications for which foreign or domestic priority is claimed in the application data sheet filed together with this application are hereby incorporated by reference into this specification in accordance with 37 CFR 1.57.

[0002] Background Technical Field Aspects of the present disclosure relate to RF (radio frequency) communication systems, and more particularly, to front - end modules for use in RF communication systems.

Background Art

[0003] Description of Related Art An RF communication system includes a front - end that couples one or more antennas to a transmit path and a receive path that communicate RF signals with a baseband system. During TDD (time - division duplex) communication, an antenna may be connected to only one of the transmit path and the receive path at a time. The front - end further includes one or more filters configured to filter out and remove frequencies from RF signals outside a given communication band. Typically, these filters will be shared between the transmit path and the receive path.

Summary of the Invention

Means for Solving the Problems

[0004] Summary of Particular Aspects of the Invention The systems, methods, and devices of the present disclosure each have a plurality of innovative aspects, any of which may not, by itself, contribute solely to the desired characteristics disclosed herein.

[0005] In one aspect, a high-frequency front-end system is provided. The high-frequency front-end system includes at least one power amplifier configured to amplify a transmitted high-frequency signal, at least one low-noise amplifier configured to receive a received high-frequency signal, an output node coupled to an antenna, and at least one switch configured to selectively couple the output node to the at least one power amplifier during a transmission period and to the at least one low-noise amplifier during a reception period, at least one transmission filter coupled between the power amplifier and the at least one switch, at least one reception filter coupled between the low-noise amplifier and the at least one switch, and a common filter coupled between the at least one switch and the output node.

[0006] The at least one power amplifier may include a plurality of power amplifiers, and the at least one low-noise amplifier may include a plurality of low-noise amplifiers.

[0007] The front-end system may further include a first multiplexer including at least one transmission filter and a second multiplexer including at least one reception filter, where the at least one transmission filter includes a plurality of transmission filters and the at least one reception filter includes a plurality of reception filters.

[0008] The at least one switch may be further configured to selectively couple one of the first multiplexer and the second multiplexer to the output node.

[0009] The front-end system may further include a first filter bank including at least one transmission filter and a second filter bank including at least one reception filter, where the at least one transmission filter includes a plurality of transmission filters and the at least one reception filter includes a plurality of reception filters.

[0010] At least one switch may be further configured to selectively couple one of the transition filters and one of the receiver filters to the output node simultaneously.

[0011] At least one power amplifier may include a first power amplifier and a second power amplifier, at least one low-noise amplifier may include a first low-noise amplifier and a second low-noise amplifier, at least one transmit filter may include a transmit diplexer, at least one receive filter may include a receive diplexer, and at least one switch includes a first switch and a second switch.

[0012] The front-end system may further include a transmit auxiliary filter and a receive auxiliary filter, at least one switch may include a connected first switch and a second switch, and the second switch may be configured to selectively couple the transmit auxiliary filter to at least one power amplifier during the transmission period and couple the receive auxiliary filter to at least one low-noise amplifier during the reception period.

[0013] The transmit auxiliary filter and the receive auxiliary filter may include shunt filters. The transmit auxiliary filter and the receive auxiliary filter may include notch filters.

[0014] In another aspect, a mobile device is provided. The mobile device includes an antenna configured to transmit a high-frequency signal to a base station, and a front-end system coupled to the antenna and configured to transmit and receive the high-frequency signal from the antenna. The front-end system includes at least one power amplifier configured to amplify a transmitted high-frequency signal, at least one low-noise amplifier configured to receive a received high-frequency signal, at least one switch configured to selectively couple the antenna to the at least one power amplifier during a transmission period and to the at least one low-noise amplifier during a reception period, at least one transmit filter coupled between the power amplifier and the at least one switch, at least one receive filter coupled between the low-noise amplifier and the at least one switch, and a common filter coupled between the at least one switch and an output node.

[0015] The at least one power amplifier may include a plurality of power amplifiers, and the at least one low-noise amplifier may include a plurality of low-noise amplifiers.

[0016] The front-end system may further include a first multiplexer including at least one transmit filter and a second multiplexer including at least one receive filter. The at least one transmit filter may include a plurality of transmit filters, and the at least one receive filter may include a plurality of receive filters.

[0017] The at least one switch may be further configured to selectively couple one of the first multiplexer and the second multiplexer to the output node.

[0018] The front-end system may further include a first filter bank including at least one transmit filter and a second filter bank including at least one receive filter. The at least one transmit filter may include a plurality of transmit filters, and the at least one receive filter may include a plurality of receive filters.

[0019] At least one switch may be further configured to selectively couple, at the same time, one of the transition filters and one of the receiver filters to the output node.

[0020] At least one power amplifier may include a first power amplifier and a second power amplifier, at least one low-noise amplifier may include a first low-noise amplifier and a second low-noise amplifier, at least one transmit filter may include a transmit diplexer, at least one receive filter may include a receive diplexer, and at least one switch may include a first switch and a second switch.

[0021] In yet another aspect, a method for operating a high-frequency front-end system is provided. The method includes, during a transmission period, coupling at least one power amplifier to an antenna via at least one switch, the switch being coupled to the at least one power amplifier via at least one transmit filter, the switch being coupled to an output node via a common filter, and the method further includes, during a reception period, coupling at least one low-noise amplifier to the antenna via at least one switch, the switch being coupled to the at least one low-noise amplifier via at least one receive filter.

[0022] The common filter may be further coupled to the antenna via the output node. At least one power amplifier may include a plurality of power amplifiers, and at least one low-noise amplifier may include a plurality of low-noise amplifiers.

[0023] In yet another aspect, a high-frequency front-end system is provided. The high-frequency front-end system includes at least one power amplifier configured to amplify a transmitted high-frequency signal, at least one low-noise amplifier configured to receive a received high-frequency signal, and, optionally, a first switch configured to couple an output node coupled to an antenna to the at least one power amplifier during a transmission period and to the at least one low-noise amplifier during a reception period, at least one transmission filter coupled between the power amplifier and the at least one switch, at least one reception filter coupled between the low-noise amplifier and the at least one switch, a transmission auxiliary filter and a reception auxiliary filter, and, optionally, a second switch configured to couple the transmission auxiliary filter to the at least one power amplifier during the transmission period and to couple the reception auxiliary filter to the at least one low-noise amplifier during the reception period.

[0024] The first switch and the second switch may be connected. The front-end system may further include a common filter coupled between the first switch and the output node.

[0025] The at least one power amplifier may include a plurality of power amplifiers, and the at least one low-noise amplifier may include a plurality of low-noise amplifiers.

[0026] The transmission auxiliary filter and the reception auxiliary filter may include a shunt filter. The shunt filter may be configured to remove a predetermined portion of the RF spectrum.

[0027] The transmission auxiliary filter and the reception auxiliary filter may include a notch filter. The transmission auxiliary filter and the reception auxiliary filter may be completely different from the at least one transmission filter and the at least one reception filter in terms of center frequency and frequency characteristics.

[0028] The second switch may be further configured to switch to one of the first auxiliary filter and the second auxiliary filter and connect it to the signal path between at least one power amplifier, at least one low-noise amplifier, and the output node, so as to dynamically reconfigure at least one transmit filter and at least one receive filter.

[0029] In another aspect, a mobile device is provided. The mobile device includes an antenna configured to transmit a high-frequency signal to a base station, and a front-end system coupled to the antenna and configured to transmit and receive the high-frequency signal from the antenna. The front-end system includes at least one power amplifier configured to amplify the transmitted high-frequency signal, at least one low-noise amplifier configured to receive the received high-frequency signal, at least one switch configured to selectively couple the antenna to the at least one power amplifier during a transmission period and to the at least one low-noise amplifier during a reception period, at least one transmit filter coupled between the power amplifier and the at least one switch, at least one receive filter coupled between the low-noise amplifier and the at least one switch, a transmit auxiliary filter, a receive auxiliary filter, and a second switch configured to selectively couple the transmit auxiliary filter to the at least one power amplifier during a transmission period and the receive auxiliary filter to the at least one low-noise amplifier during a reception period.

[0030] The first switch and the second switch may be connected. The front-end system may further include a common filter coupled between the first switch and the output node.

[0031] The at least one power amplifier may include a plurality of power amplifiers, and the at least one low-noise amplifier may include a plurality of low-noise amplifiers.

[0032] The transmit auxiliary filter and the receive auxiliary filter may include shunt filters. The shunt filter may be configured to remove a predetermined portion of the RF spectrum.

[0033] The transmit auxiliary filter and the receive auxiliary filter may include a notch filter. The transmit auxiliary filter and the receive auxiliary filter may be completely different from at least one transmit filter and at least one receive filter in terms of center frequency and frequency characteristics.

[0034] In yet another aspect, a method for operating a high-frequency front-end system is provided. The method includes, during a transmission period, coupling at least one power amplifier to an antenna via a first switch, the first switch being coupled to the at least one power amplifier via at least one transmit filter, and the method further includes, during a reception period, coupling at least one low-noise amplifier to the antenna via the first switch, the first switch being coupled to the at least one low-noise amplifier via at least one receive filter, and the method further includes, during the transmission period, coupling a transmit auxiliary filter to the at least one power amplifier via a second switch, and, during the reception period, coupling a receive auxiliary filter to the at least one low-noise amplifier via the second switch.

[0035] A common filter may be coupled between the first switch and the antenna. The at least one power amplifier may include a plurality of power amplifiers, and the at least one low-noise amplifier may include a plurality of low-noise amplifiers.

Brief Description of the Drawings

[0036]

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DETAILED DESCRIPTION OF THE INVENTION

[0037] DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION In the following detailed description of specific embodiments, various descriptions are presented for specific embodiments. However, the innovation described herein can be embodied in many different ways, for example, as set forth and included in the claims. This description refers to the drawings, in which the same or functionally similar elements may be denoted by the same reference numerals. It will be understood that the elements shown in the drawings are not necessarily to scale. It will also be understood that a particular embodiment may include a greater number of elements than those shown in the drawings and / or may include a subset of the elements shown in the drawings. Furthermore, some embodiments may incorporate any suitable combination of features included in two or more of the drawings.

[0038] ITU (International Telecommunication Union) is a specialized agency of the UN (United Nations) that is responsible for global issues related to information and communication technologies, including the worldwide co-use of the radio spectrum.

[0039] 3GPP (3rd Generation Partnership Project) is a collaboration by a group of global telecommunication standards standardization organizations such as ARIB (Association of Radio Industries and Businesses), TTC (Telecommunications Technology Committee), CCSA (China Communications Standards Association), ATIS (Alliance for Telecommunications Industry Solutions), TTA (Telecommunications Technology Association of Korea), ETSI (European Telecommunications Standards Institute), and TSDSI (Telecommunications Standards Development Society of India).

[0040] In its activities within the scope of ITU, 3GPP creates and manages the technical specifications of various mobile communication technologies, including, for example, 2G (second generation) technologies (such as GSM (Global System for Mobile Communications) and EDGE (Enhanced Data Rates for GSM Evolution)), 3G (third generation) technologies (such as UMTS (Universal Mobile Telecommunications System) and HSPA (High Speed Packet Access)), and 4G (fourth generation) technologies (such as LTE (Long Term Evolution) and LTE-Advanced).

[0041] By releasing specifications, the technical specifications managed by 3GPP can be extended and revised. Specification releases can be carried out over several years and can specify new features and evolving extensions.

[0042] In one example, 3GPP adopted carrier aggregation (CA) for LTE in Release 10. Initially starting with two downlink carriers, in Release 14, 3GPP extended carrier aggregation to include up to five downlink carriers and up to three uplink carriers. Other examples of new features and evolutions brought about by 3GPP releases include, but are not limited to, LAA (License Assisted Access), eLAA (enhanced LAA), NB-IoT (Narrowband Internet of Things), V2X (Vehicle-to-Everything), and HPUE (High Power User Equipment).

[0043] In Release 15, 3GPP adopted Phase 1 of 5G (fifth generation) technology, and in Release 16 (targeted for 2020), it is planned to adopt Phase 2 of 5G technology. Subsequent 3GPP releases should further evolve and expand 5G technology. Also, 5G technology is also referred to as 5G NR (New Radio) in this specification.

[0044] 5G NR is planned to support or be capable of supporting various functions such as communication in millimeter wave spectrum, beamforming functions, waveforms with high spectral efficiency, low latency communication, multiple radio numerologies, and / or NOMA (Non-Orthogonal Multiple Access). Such RF functions give flexibility to the network to improve the transfer speed of user data, but corresponding to such functions may bring multiple technical challenges.

[0045] The teachings herein are applicable to a wide variety of communication systems, including communication systems utilizing state-of-the-art cellular technologies such as, but not limited to, LTE-Advanced, LTE-Advanced Pro, and / or 5G NR.

[0046] FIG. 1A is a schematic diagram of an example of a communication network 10. The communication network 10 includes a macrocell base station 1, a small cell base station 3, and various examples of UEs (user equipment) including a first mobile device 2a, a wirelessly connected vehicle 2b, a laptop 2c, a stationary wireless device 2d, a wirelessly connected train 2e, a second mobile device 2f, and a third mobile device 2g.

[0047] Although FIG. 1A shows specific examples of base stations and user equipment, the communication network can include a wide variety of types and / or numbers of base stations and user equipment.

[0048] For example, in the illustrated example, the communication network 10 includes a macro cell base station 1 and a small cell base station 3. The small cell base station 3 can operate at a relatively low power, over a short distance, and / or with a small number of simultaneous users compared to the macro cell base station 1. Also, the small cell base station 3 may be referred to as a femto cell, a pico cell, or a micro cell. Although the communication network 10 is illustrated as including two base stations, the communication network 10 can be implemented to include a greater or lesser number of base stations and / or other types of base stations.

[0049] Although various examples of user equipment are illustrated, the teachings herein are applicable to a wide variety of user equipment including, but not limited to, mobile phones, tablet terminals, laptops, IoT devices, wearable electronics, CPE (Customer Premises Equipment), wirelessly connected vehicles, wireless repeaters, and / or various other communication devices. Further, the user equipment includes not only currently available communication devices that operate in cellular networks, but also subsequently developed communication devices that will be readily implementable in conjunction with the systems, processes, methods, and apparatuses of the inventions described or claimed herein.

[0050] The illustrated communication network 10 of FIG. 1A is adapted to communicate using various cellular technologies including, for example, 4G LTE and 5G NR. In certain embodiments, the communication network 10 is made to provide a WLAN (Wireless Local Area Network) such as WiFi. Although various examples of communication technologies are provided, the communication network 10 can be made to accommodate a wide variety of communication technologies.

[0051] The various communication links of communication network 10 are represented in FIG. 1A. These communication links can be duplexed in a variety of ways, including, for example, the use of FDD (Frequency Division Duplexing) and / or TDD (Time Division Duplexing). FDD is a type of high-frequency communication that uses different frequencies for signal transmission and reception. FDD can provide several advantages, such as fast data transfer speeds and low latency. In contrast, TDD is a type of high-frequency communication that uses approximately the same frequency for signal transmission and reception, and the transmission and reception of communication can be switched without delay. TDD can provide several advantages, such as efficient use of the spectrum and adjustable throughput allocation between the transmission direction and the reception direction.

[0052] In certain embodiments, the user equipment can communicate with the base station using one or more of 4G LTE technology, 5G NR technology, and WiFi technology. In certain embodiments, enhanced license assisted access (eLAA) is used such that one or more licensed frequency carriers (e.g., licensed 4G LTE and / or 5G NR frequencies) are bundled with one or more unlicensed carriers (e.g., unlicensed WiFi frequencies).

[0053] As shown in FIG. 1A, the communication links include not only the communication links between the UE and the base station, but also the communication between the UE and the UE, and the communication between the base station and the base station. For example, the communication network 10 can be implemented to correspond to a self-front-haul and / or a self-back-haul (e.g., between mobile device 2g and mobile device 2f).

[0054] The communication link can operate at a variety of frequencies. In certain embodiments, the communication is supported using 5G NR technology in one or more frequency bands below 6 GHz (gigahertz) and / or 5G NR technology in one or more frequency bands greater than 6 GHz. For example, the communication link can be used for FR1 (Frequency Range1), FR2 (Frequency Range2), or a combination thereof. In one embodiment, one or more of the mobile devices comply with the HPUE power class standard.

[0055] In certain embodiments, the base station and / or user equipment communicate using beamforming. For example, beamforming can be used to concentrate the signal strength to overcome path losses such as the high losses associated with communication at high signal frequencies. In certain embodiments, user equipment such as one or more mobile phones communicate using beamforming in the millimeter wave frequency band in the range of 30 GHz to 300 GHz and / or the upper limit band of the centimeter wave frequency in the range of 6 GHz to 30 GHz, more specifically, 24 GHz to 30 GHz.

[0056] Different users of the communication network 10 can share available network resources such as the available frequency spectrum in a variety of ways.

[0057] In one example, FDMA (Frequency Division Multiple Access) is used to divide one frequency band into multiple frequency carriers. In addition, one or more carriers are assigned to a particular user. Examples of FDMA include, but are not limited to, SC-FDMA (Single Carrier FDMA) and OFDMA (Orthogonal FDMA). OFDMA is a multi-carrier technology that further divides one available bandwidth into multiple narrowband sub-carriers that are orthogonal to each other. The plurality of narrowband sub-carriers can be separately assigned to different users.

[0058] As other examples of shared access, there are TDMA (Time Division Multiple Access) in which specific time slots for using frequency resources are allocated to users, CDMA (Code Division Multiple Access) in which frequency resources are shared among users by allocating different unique codes to each user, SDMA (Space Division Multiple Access) in which shared access is provided by space division using beamforming, NOMA (Non-Orthogonal Multiple Access) in which power domains are used for multiple access, etc., but not limited to these. For example, by using NOMA, it becomes possible to support multiple users with the same frequency, the same time, and / or the same code but different power levels.

[0059] eMBB (enhanced mobile broadband) refers to technologies for increasing the system capacity of LTE networks. For example, eMBB can refer to communication at a peak data transfer rate of at least 10 Gbps and a peak data transfer rate of at least 100 Mbps per user. uRLLC (Ultra-Reliable Low-Latency) refers to technologies for communication with very little latency, for example, less than 2 milliseconds. uRLLC can be used for mission-critical communication for applications such as autonomous driving and / or remote surgery. mMTC (Massive Machine-Type Communications) refers to low-cost and low-data-transfer-rate communication associated with wireless connection to everyday objects such as those related to IoT (Internet of Things) applications.

[0060] Using the communication network 10 of FIG. 1A, it is possible to support a variety of advanced communication functions including eMBB, uRLLC, and / or mMTC (not limited to these).

[0061] Figure 1B is a schematic diagram of an example of a mobile device 2a that communicates via a cellular network and a WiFi network. For example, as shown in Figure 1B, the mobile device 2a communicates with a base station 1 of the cellular network and a WiFi access point 3 of the WiFi network. Further, Figure 1B also shows an example of other UEs (user equipment) communicating with the base station 1, such as a wirelessly connected vehicle 2b and another mobile device 2c. Additionally, Figure 1B shows an example of other WiFi-enabled devices communicating with the WiFi access point 3, such as a laptop 4.

[0062] Specific examples of cellular UEs and WiFi-enabled devices have been shown, but a wide variety of types of devices can communicate using cellular and / or WiFi networks. Such devices include, but are not limited to, mobile phones, tablet terminals, laptops, IoT (Internet of Things) devices, wearable electronic devices, CPE (Customer Premises Equipment), wirelessly connected vehicles, wireless relay devices, and / or a wide variety of other communication devices.

[0063] In certain embodiments, UEs, such as the mobile device 2a in Figure 1B, are implemented to support communication using a number of technologies including, but not limited to, 2G, 3G, 4G (including LTE, LTE-Advanced, and LTE-Advanced Pro), 5G NR, WLAN (e.g., WiFi), WPAN (e.g., Bluetooth® and ZigBee), WMAN (e.g., WiMax), and / or GPS. In certain embodiments, enhanced license assisted access (eLAA) is used such that one or more licensed frequency carriers (e.g., licensed 4G LTE and / or 5G NR frequencies) are aggregated with one or more unlicensed carriers (e.g., unlicensed WiFi frequencies).

[0064] Furthermore, a particular UE can communicate not only with base stations and access points, but also with other UEs. For example, a wirelessly connected vehicle 2b can communicate with a wirelessly connected pedestrian 2d, a wirelessly connected traffic signal 2e, and / or another wirelessly connected vehicle 2f that utilizes vehicle-to-vehicle (V2V) and / or vehicle-to-everything (V2X) communications.

[0065] Although various examples of communication technologies have been described, mobile devices can be implemented to support a wide range of communications.

[0066] Various communication links are shown in FIG. 1B. These communication links can be multiplexed in a variety of ways, including, for example, the use of frequency division duplexing (FDD) and / or time division duplexing (TDD). FDD is a type of high-frequency communication that uses different frequencies for signal transmission and reception. FDD can provide several advantages, such as fast data transfer speeds and low latency. In contrast, TDD is a type of high-frequency communication that uses approximately the same frequency for signal transmission and reception, and the transmission and reception of communication can be switched without delay. TDD can provide several advantages, such as efficient use of the spectrum and adjustable throughput allocation between the transmission direction and the reception direction.

[0067] Different users of the illustrated communication network can share available network resources, such as the available frequency spectrum, in a variety of ways. In one example, frequency division multiple access (FDMA) is used to divide one frequency band into multiple frequency carriers. In addition, one or more carriers are assigned to a particular user. Examples of FDMA include, but are not limited to, single carrier FDMA (SC-FDMA) and orthogonal FDMA (OFDMA). OFDM is a multi-carrier technology that further divides one available bandwidth into multiple narrowband sub-carriers that are orthogonal to each other. The multiple narrowband sub-carriers can be separately assigned to different users.

[0068] As other examples of common access, there are TDMA (Time Division Multiple Access) in which specific time slots for using frequency resources are assigned to users, CDMA (Code Division Multiple Access) in which frequency resources are shared among users by assigning different unique codes to each user, SDMA (Space Division Multiple Access) in which common access is provided by space division using beamforming, NOMA (Non-Orthogonal Multiple Access) in which power domains are used for multiple access, and the like, but not limited thereto. For example, by using NOMA, it becomes possible to support multiple users with the same frequency, the same time, and / or the same code but different power levels.

[0069] A specific RF communication system includes multiple transceivers for communicating using different wireless networks across multiple frequency bands and / or using different communication standards. By implementing the RF communication system in this way, functions can be extended, bandwidth can be increased, and / or flexibility can be enhanced, but several intermingled issues can arise among the transceivers operating within the RF communication system.

[0070] For example, an RF communication system may include a cellular transceiver for processing RF signals communicated in a cellular network and a WLAN transceiver for processing RF signals communicated in a WLAN (Wireless Local Area Network) network such as a WiFi network. For example, the mobile device 2a in FIG. 1B is operable to communicate using a cellular network and a WiFi network.

[0071] Although implementing the RF communication system in this way provides several benefits, there is a risk of an impact that reduces the sensitivity of each other due to cellular transmissions that interfere with the reception of WiFi signals and / or WiFi transmissions that interfere with the reception of cellular signals.

[0072] In one example, Cellular Band 7 may cause mutual sensitivity degradation with respect to 2.4 GHz Wi-Fi. For example, Band 7 is in the FDD duplex mode, operates in a frequency band of approximately 2.62 GHz to 2.69 GHz for the downlink, and operates in a frequency band of approximately 2.50 GHz to approximately 2.57 GHz for the uplink, while 2.4 GHz Wi-Fi is in the TDD duplex mode and operates in a frequency band of approximately 2.40 GHz to approximately 2.50 GHz. Therefore, Cellular Band 7 and 2.4 GHz Wi-Fi have adjacent frequencies, and RF signal leakage from the high-power transmitter of one transceiver / front-end may affect the performance of the receiver of the other transceiver / front-end, especially at the boundary frequency channels.

[0073] In another example, Cellular Band 40 and 2.4 GHz Wi-Fi may cause mutual sensitivity degradation. For example, Band 40 is in the TDD duplex mode and operates in a frequency band of approximately 2.30 GHz to approximately 2.40 GHz, while 2.4 GHz Wi-Fi is in the TDD duplex mode and operates in a frequency band of approximately 2.40 GHz to approximately 2.50 GHz. Thus, Cellular Band 40 and 2.4 GHz Wi-Fi have adjacent frequencies, and several mixed problems are caused especially at the boundary frequency channels.

[0074] The sensitivity degradation may be caused not only by the direct leakage of the interfering transmitted signal to the victim receiver, but also by the spectral regrowth components generated in the transmitter. Such interference may be relatively closely related in frequency to the victim received signal and / or may directly overlap the received signal.

[0075] Figure 2 is a schematic diagram of an embodiment of a mobile device 800. The mobile device 800 includes a baseband system 801, a transceiver 802, a front-end system 803, an antenna 804, a power management system 805, a memory 806, a user interface 807, and a battery 808.

[0076] Using the mobile device 800, communication can be performed using a variety of communication technologies, including 2G technology, 3G technology, 4G technology (including LTE, LTE-Advanced, and LTE-Advanced Pro), 5G NR, WLAN technology (e.g., WiFi), WPAN technology (e.g., Bluetooth and ZigBee), WMAN technology (e.g., WiMax), and / or GPS technology (not limited to these).

[0077] The transceiver 802 generates the RF signals to be transmitted and processes the RF signals received from the antenna 804. It will be understood that various functions related to the transmission and reception of RF signals can be realized by one or more components collectively represented as the transceiver 802 in FIG. 2. In one example, separate components (e.g., separate circuits or dies) for handling specific types of RF signals can be provided.

[0078] The front-end system 803 assists in adjusting the signals transmitted to the antenna 804 and / or the signals received from the antenna 804. In the illustrated embodiment, the front-end system 803 includes an antenna tuning circuit 810, a PA (power amplifier) 811, an LNA (low noise amplifier) 812, a filter 813, a switch 814, and a signal splitting / combining circuit 815. However, other embodiments are possible.

[0079] For example, the front-end system 803 can provide a number of functions, including amplification of the transmitted signal, amplification of the received signal, filtering of the signal, switching between different bands, switching between different power modes, switching between the transmit mode and the receive mode, signal duplexing, signal multiplexing (e.g., duplexing or triplexing) (not limited to these), or some combination thereof.

[0080] In certain embodiments, mobile device 800 flexibly improves peak data transfer speeds by supporting carrier aggregation. Carrier aggregation can be utilized for both FDD (Frequency Division Duplexing) and TDD (Time Division Duplexing), and may be used to bundle multiple carriers or multiple channels. Carrier aggregation includes contiguous aggregation where contiguous carriers within the same operating frequency band are bundled. Also, carrier aggregation can be non - contiguous carrier aggregation and may include carriers with frequencies separated within a common band or different bands.

[0081] Antenna 804 can include antennas used for a wide variety of types of communication. For example, antenna 804 can include antennas for transmitting and / or receiving signals associated with a wide variety of frequencies and communication standards.

[0082] In certain embodiments, antenna 804 is compatible with MIMO communication and / or switched diversity communication. For example, MIMO communication uses multiple antennas to communicate multiple data streams over a single high - frequency channel. MIMO communication benefits from high SNR, improved coding, and / or suppression of signal interference due to differences in the spatial multiplexing of the wireless environment. Switched diversity refers to communication where a particular antenna is selected to operate at a particular time. For example, a switch can be used to select a particular antenna from a group of antennas based on various factors such as the observed bit error rate and / or signal strength indicator.

[0083] In certain embodiments, the mobile device 800 may operate with beamforming. For example, the front-end system 803 may include an amplifier with a controllable gain and a phase shifter with a controllable phase to provide beamforming and beam directivity for transmitting and / or receiving signals using the antenna 804. For example, in the context of signal transmission, the amplitude and phase of the transmission signal provided to the antenna 804 are controlled to synthesize the emitted signals from the antenna 804 using constructive and destructive interference to generate an aggregate transmission signal that exhibits a quality such as a beam having a greater signal strength propagating in a given direction. In the context of signal reception, the amplitude and phase are controlled so that more signal energy is received when signals arrive at the antenna 804 from a particular direction. In certain embodiments, to enhance beamforming, the antenna 804 includes one or more arrays composed of antenna elements.

[0084] To facilitate the processing of various user I / O (input / output) such as voice and data, the baseband system 801 is coupled to the user interface 807. The baseband system 801 provides a digital representation of the transmission signal to the transceiver 802, and the transceiver 802 processes this digital representation to generate a transmission RF signal. Also, the baseband system 801 processes the digital representation of the received signal provided by the transceiver 802. As shown in FIG. 2, to facilitate the operation of the mobile device 800, the baseband system 801 is coupled to the memory 806.

[0085] The memory 806 can be used for a variety of purposes, such as storing data and / or instructions to facilitate the operation of the mobile device 800 and / or to provide a storage location for user information.

[0086] The power management system 805 provides multiple power management functions for the mobile device 800. In a particular embodiment, the power management system 805 includes a PA power control circuit that controls the power voltage of the power amplifier 811. For example, the power management system 805 can be configured to change the power voltage(s) applied to one or more of the power amplifiers 811 to improve efficiency such as PAE (Power Added Efficiency).

[0087] As shown in FIG. 2, the power management system 805 receives a battery voltage from the battery 808. The battery 808 can be any suitable battery for use in the mobile device 800, including, for example, a lithium-ion battery.

[0088] FIG. 3 is a schematic diagram of a power amplifier system 860 according to an embodiment. The illustrated power amplifier system 860 includes a baseband processor 841, a transmitter / observation receiver 842, a PA (Power Amplifier) 843, a directional coupler 844, a front-end circuit 845, an antenna 846, a PA bias control circuit 847, and a PA power control circuit 848. The illustrated transmitter / observation receiver 842 includes an I / Q modulator 857, a mixer 858, and an ADC (Analog / Digital Converter) 859. In a particular embodiment, the transmitter / observation receiver 842 is incorporated into a transceiver.

[0089] The baseband processor 841 can be used to generate I (in-phase) signals and Q (quadrature-phase) signals. The I and Q signals can be used to represent a sine wave or a signal having a desired amplitude, a desired frequency, and a desired phase. For example, the I signal can be used to represent the in-phase component of a sine wave, and the Q signal can be used to represent the quadrature-phase component of a sine wave. The I and Q signals can be an equivalent representation of a sine wave. In certain embodiments, the I and Q signals can be provided to the I / Q modulator 857 in digital form. The baseband processor 841 can be any suitable processor configured to process baseband signals. For example, the baseband processor 841 can include a digital signal processor, a microprocessor, a programmable core, or any combination thereof. Also, in some embodiments, two or more baseband processors 841 can be included in the power amplifier system 860.

[0090] The I / Q modulator 857 can be configured to receive the I and Q signals from the baseband processor 841 and process the I and Q signals to generate an RF signal. For example, the I / Q modulator 857 can include a DAC (digital / analog converter) configured to convert the I and Q signals to analog form, a mixer for converting the frequencies of the I and Q signals to a higher frequency to make them RF, and a signal synthesizer for synthesizing the I and Q signals converted to the higher frequency into an RF signal suitable for amplification by the power amplifier 843. In certain embodiments, the I / Q modulator 857 can include one or more filters configured to filter the frequency components of the internally processed signals.

[0091] The power amplifier 843 can receive the RF signal from the I / Q modulator 857 and, when turned on, can provide the amplified RF signal to the antenna 846 via the front-end circuit 845.

[0092] The front-end circuit 845 can be implemented in various ways. In one example, the front-end circuit 845 includes one or more switches, one or more filters, one or more diplexers, one or more multiplexers, and / or one or more other components. In another example, the front-end circuit 845 is omitted by choosing for the power amplifier 843 to directly provide the amplified RF signal to the antenna 846.

[0093] The directional coupler 844 senses the output signal of the power amplifier 823. In addition to this, the sensed output signal from the directional coupler 844 is provided to the mixer 858. The mixer 858 multiplies the sensed output signal by a reference signal of the control frequency. The mixer 858 operates to generate a downshift signal by downshifting the frequency components of the sensed output signal. This downshift signal can be provided to the ADC 859. The ADC 859 converts the downshift signal into a digital format suitable for processing by the baseband processor 841. By providing a feedback path from the output of the power amplifier 843 to the baseband processor 841, several advantages can be obtained. For example, by implementing the baseband processor 841 in this way, it is possible to assist in controlling the power supply, compensating for when the transmitter is damaged, and / or performing DPD (digital predistortion). An example of the detection path of the power amplifier has been shown, but other embodiments are also possible.

[0094] The PA power control circuit 848 receives a power control signal from the baseband processor 841 and controls the power supply voltage of the power amplifier 843. In the illustrated configuration, the PA power control circuit 848 generates a first power supply voltage V CC1 for supplying power to the input stage of the power amplifier 843 and a second power supply voltage V CC2 for supplying power to the output stage of the power amplifier 843. The PA power control circuit 848 can control the voltage levels of the first power supply voltage V CC1 and / or the second power supply voltage V CC2 to improve the PAE of the power amplifier system.

[0095] The PA power control circuit 848 can reduce power loss by adopting various power management techniques to change the voltage level of one or more power supply voltages among a plurality of power supply voltages over time and improving the PAE (Power Added Efficiency) of the power amplifier.

[0096] One technique for improving the efficiency of the power amplifier is APT (Average Power Tracking) that uses a DC / DC converter to generate the power supply voltage of the power amplifier based on the average output power of the power amplifier. Another technique for improving the efficiency of the power amplifier is ET (Envelope Tracking) in which the power supply voltage of the power amplifier is controlled corresponding to the envelope of the RF signal. Therefore, when the voltage level of the envelope of the RF signal rises, the voltage level of the power supply voltage of the power amplifier may also be raised. Similarly, when the voltage level of the envelope of the RF signal drops, the voltage level of the power supply voltage of the power amplifier may also be lowered, and the power consumption may be reduced.

[0097] In a specific configuration, the PA power control circuit 848 is a multi-mode power control circuit that can operate in a plurality of supply control modes including the APT mode and the ET mode. For example, a power control signal from the baseband processor 841 may instruct the PA power control circuit 848 to operate in a specific supply control mode.

[0098] As shown in FIG. 3, the PA bias control circuit 847 receives a bias control signal from the baseband processor 841 and generates a bias control signal for the power amplifier 843. In the illustrated configuration, the bias control circuit 847 generates a bias control signal for both the input stage and the output stage of the power amplifier 843. However, other embodiments are also possible.

[0099] FIG. 4A is a schematic diagram of an embodiment of the packaged module 900. FIG. 4B is a schematic cross-sectional view of the packaged module 900 of FIG. 4A along the line 4B-4B.

[0100] The packaged module 900 includes a high-frequency component 901, a semiconductor die 902, a surface-mounted component 903, wire bonds 908, a package substrate 920, and a encapsulation structure 940. The package substrate 920 includes pads 906 formed from conductors disposed therein. In addition to this, the semiconductor die 902 includes pins or pads 904, and wire bonds 908 are used to connect the pads 904 of the die 902 to the pads 906 of the package substrate 920.

[0101] The semiconductor die 902 includes a power amplifier 945. The power amplifier 945 can be implemented according to one or more features described herein.

[0102] The package substrate 920 can be configured to house a plurality of components such as the high-frequency component 901, the semiconductor die 902, and the surface-mounted component 903. The surface-mounted component 903 can include, for example, surface-mounted capacitors and / or surface-mounted inductors. In one embodiment, the high-frequency component 901 includes an IPD (Integrated Passive Device).

[0103] As shown in FIG. 4B, it is illustrated that a plurality of contact pads 932 are disposed on a surface of the packaged module 900 opposite to the surface used for disposing the semiconductor die 902. By configuring the packaged module 900 in this way, it is possible to assist in connecting the packaged module 900 to a wiring substrate such as a mobile phone substrate of a mobile device. Exemplary contact pads 932 can be configured to provide high-frequency signals, bias signals, and / or power (e.g., power supply voltage and ground) to the semiconductor die 902 and / or other components. As shown in FIG. 4B, the electrical connection between the contact pad 932 and the semiconductor die 902 can be facilitated by a connection portion 933 that passes to the package substrate 920. The connection portion 933 can represent an electrical path formed up to the package substrate 920, such as a connection portion related to vias and conductors of a multilayer laminated package substrate.

[0104] Also, in some embodiments, the packaged module 900 may include one or more packaging structures, for example, for facilitating protection and / or handling. Such a packaging structure may include an overmolded or encapsulated structure 940 formed to cover the package substrate 920 and the components and dies (if any) disposed thereon.

[0105] Although the packaged module 900 has been described in the context of wirebond-based electrical connections, it will be understood that one or more features of the present disclosure can be implemented in other packaging configurations, such as, for example, a flip-chip configuration.

[0106] FIG. 5 is a schematic diagram of an embodiment of an RF communication system 1620 including a transceiver / RF front end 1603 (or simply an RF front end). Specifically, the RF communication system includes a baseband modem 1602, an RF front end 1603, a power management 1604, and a plurality of antennas 1601a-1601n.

[0107] The RF front end 1603 is connected to the baseband modem 1602 and transmits and receives baseband signals therebetween. The baseband signals received from the baseband modem 1602 are processed by the RF front end so as to be wirelessly transmitted via the antennas 1601a-1601n. Similarly, the RF signals received via the antennas 1601a-1601n are processed by the RF front end 1603 before being provided to the baseband modem 1602.

[0108] The power management 1604 provides power to each of the baseband modem 1602 and the RF front end 1603. For this purpose, the power management 1604 includes a PMU (Power Management Unit) baseband 1611 configured to provide power to the baseband modem 1602 and a PMU RF 1612 configured to provide power to the RF front end 1603.

[0109] The RF front end 1603 includes a MUX / DEMUX block 1605, a beamforming block 1606, a data conversion block 1607, a mixing block 1608, an amplification block 1609, and a filter processing / switching block 1610. The MUX / DEMUX block 1605 can be configured to control the flow of RF signals from the remaining components of the RF front end 1603 to the baseband modem 1602 via a plurality of communication band paths, and the flow of RF signals from the baseband modem 1602 to the remaining components of the RF front end 1603 via a plurality of communication band paths. The beamforming block 1606 is configured to adjust the gain and / or phase of a plurality of RF signals transmitted and received between the antennas 1601a to 1601n to direct the beam so as to concentrate the signal strength in a desired direction.

[0110] The data conversion block 1607 may include a plurality of DACs configured to convert the signals received from the beamforming block 1606 into an analog format. Further, the data conversion block 1607 may include a plurality of ADCs configured to convert the analog signals received from the mixing block 1608 into a digital format. The mixing block 1608 may include a plurality of LOs (local oscillators), and is configured to convert the frequency of the analog signals received from the data conversion block 1607 to a higher frequency and convert the frequency of the signals received from the amplification block 1609 to a lower frequency.

[0111] The amplification block 1609 may include a plurality of PAs configured to amplify the signals received from the mixing block, and a plurality of LNAs configured to amplify the signals received from the filter processing / switching block 1610. The filter processing / switching block 1610 includes a plurality of filters configured to filter out and remove frequencies that do not form a part of the corresponding communication band, and a plurality of switches configured to selectively connect the antennas 1601a to 1601n to one or more of the communication bands.

[0112] Embodiments of the RF Front End Module As described above, a communication system typically includes an RF front end designed to connect a baseband model to one or more antennas and process RF signals communicated therebetween.

[0113] In a conventional TDD RFFE (RF Front End) for mobile phones, a common filter may be used for both the transmit path and the receive path to save area and cost. Such a common filter may have competing design goals, including (a) sufficiently high rejection for interferences relatively close to the band boundaries, such as three blockers in the 3GPP range in the receive mode, and (b) sufficiently low insertion loss to obtain a highly efficient module in the transmit mode. In the case of a specific band, it may be even more difficult to achieve the above-described design goals if a given band is relatively close to another band. For example, within the 5G standard, band n79 is located only 125 MHz from the upper boundary of the band for the first WiFi 5 GHz channel. As another example, in the case of 5G band n77, strong HB and WiFi 2.4 GHz interferences are located only a few hundred MHz from the lower boundary of the n77 band.

[0114] In addition to this, 5G NR has strict regulatory requirements, including the requirement that the power amplifier exhibit high linearity (e.g., linearity at the threshold level) so as not to emit unnecessary emissions in adjacent public bands and military bands. To make room for mobile phones, bands n77 and n79 may be sent to a shared antenna via a multiplexer. Bands n77 and n79 are two examples of 5G NR TDD bands where TX and RX share the path to the antenna port of the RFFE module. Similarly, a multiplexer can be used such that the path of band n79 is shared between n79 transmit and n79 receive.

[0115] When coexisting with WiFi forces the removal of more than 50 dB of transmit noise on the lower side of Band B41 without affecting the insertion loss of the filter during the receive period of the TDD frame, there is another difficult trade-off in Band B41.

[0116] FIG. 6A is an exemplary multi-band RF front-end 203 that can be used for TDD according to an aspect of the present disclosure. The exemplary RF front-end 203 may be configured to transmit and receive N bands, such as Band1, Band2, …, BandN. The RF front-end 203 includes a plurality of power amplifiers 204A, 204B, …, 204N, a plurality of low-noise amplifiers 206A, 206B, …, 206N, a plurality of transmit / receive switches 208A, 208B, …, 208N, and a multiplexer 210 including a plurality of filters 210A, 210B, …, 210N.

[0117] Referring to Band1 as an example, each band within the RF front-end 203 may have a power amplifier 204A dedicated to the transmit path and a low-noise amplifier 206A dedicated to the receive path. The transmit path and the receive path of Band1 are combined into one via the corresponding transmit / receive switch 208A. Each of the transmit / receive switches 208A to 208N is connected to the multiplexer 210 and connects the bands Band1 to BandN to an output node connected to one or more antennas. The filters 210A to 210N can be implemented as band-pass filters configured to pass frequencies related to the corresponding bands Band1 to BandN.

[0118] FIG. 6B is another exemplary multi-band RF front-end 203 that can be used for TDD according to an aspect of the present disclosure. In particular, the RF front-end 203 of FIG. 6B may be configured as a high-performance TDD RF front-end 203. Similar to the example of FIG. 6A, the exemplary RF front-end 203 may be configured to transmit and receive N bands, namely Band1, Band2, …, BandN. The RF front-end 203 includes a plurality of power amplifiers 204A, 204B, …, 204N, a plurality of low-noise amplifiers 206A, 206B, …, 206N, a first filter bank 210 including a first plurality of filters 210A, 210B, …, 210N, a second filter bank 212 including a second plurality of filters 212A, 212B, …, 212N, and a single-pole N-throw transmit / receive switch 214.

[0119] To improve performance compared to FIG. 6A, the embodiment of FIG. 6B has two sets of individual filters, the first filters 210A to 210N for transmitting RF signals and the second filters 212A to 212N for receiving RF signals. In an embodiment where the RF front-end 203 is configured to support simultaneous transmission and reception between configured bands Band1 to BandN, the transmit path and the receive path are connected to the transmit / receive switch 214. The transmit / receive switch 214 may be configured to simultaneously connect a plurality of receive paths and transmit paths to an output node connected to one or more antennas.

[0120] FIG. 6C is yet another exemplary multi-band RF front-end 203 that can be used for TDD according to an aspect of the present disclosure. In particular, the RF front-end 203 of FIG. 6B may be configured as another example of a high-performance TDD RF front-end 203. Compared with FIG. 6B, the insertion loss of the embodiment of FIG. 6C is low (thus, the TX efficiency is high). This is because the number of throws of the TDD switch is small. Similar to the example of FIG. 6B, the exemplary RF front-end 203 may be configured to transmit and receive N bands Band1, Band2, …, BandN. The RF front-end 203 includes a plurality of power amplifiers 204A, 204B, …, 204N, a plurality of low-noise amplifiers 206A, 206B, …, 206N, a first multiplexer 210 including a first plurality of filters 210A, 210B, …, 210N, a second multiplexer 212 including a second plurality of filters 212A, 212B, …, 212N, and a single-pole double-throw transceiver switch 216.

[0121] In an embodiment where the RF front-end 203 does not support simultaneous transmission and reception between the configured bands Band1 to BandN, the transceiver switch 216 is connected to the common node of each of the first multiplexer 210 and the second multiplexer 212 that are selectively connected to the output node.

[0122] FIG. 7A is a diagram showing an exemplary RF front-end 310 portion for two bands according to an aspect of the present disclosure. As shown in FIG. 7A, the RF front-end 310 includes a first power amplifier 402, a second power amplifier 404, a first low-noise amplifier 406, a second low-noise amplifier 408, a first transceiver switch 410, a second transceiver switch 412, and a diplexer 414.

[0123] The first power amplifier 402, the first low-noise amplifier 406, and the first switch 410 may be configured to transmit and receive RF signals in the first band using TDD, and the second power amplifier 404, the second low-noise amplifier 408, and the second switch 412 may be configured to transmit and receive RF signals in the second band using TDD. The first transmit / receive switch 410 and the second transmit / receive switch 412 can be configured such that each of the first band and the second band is in either a transmit mode or a receive mode. The diplexer 414 may be composed of a pair of band-pass filters. These band-pass filters respectively pass RF signals corresponding to the first band and the second band between the output node and the first transmit / receive switch 410 and the second transmit / receive switch 412, respectively.

[0124] In the case of certain bands (e.g., band n77 and band n79), aspects of the present disclosure relate to addressing at least some of the above-described problems related to adjacent bands. For example, aspects of the present disclosure relate to (a) sufficiently high rejection for interferences relatively close to the band boundaries, such as three interferences in the 3GPP range, in the receive mode, and (b) sufficiently low insertion loss to obtain a highly efficient module in the transmit mode, for competing design goals. In the embodiment of FIG. 7A, since one common filter is used for both RX and TX, in competing design goals, a compromise will have to be made in either rejection or insertion loss.

[0125] FIG. 7B is a diagram showing another exemplary RF front-end 310 portion for two bands according to an aspect of the present disclosure. In this embodiment, the RF front-end 310 includes a first power amplifier 402, a second power amplifier 404, a first low-noise amplifier 406, a second low-noise amplifier 408, a first transmit / receive switch 410, a second transmit / receive switch 412, a first diplexer 416, and a second diplexer 418.

[0126] In the example of FIG. 7B, rather than using one common diplexer (such as diplexer 414 in FIG. 7A) for both the receive mode and the transmit mode of TDD, the embodiment of FIG. 7B includes separate first diplexer 416 and second diplexer 418. The first diplexer 416 and the second diplexer 418 can be configured to address different sets of specifications and / or design constraints for the receive path as well as the transmit path.

[0127] For example, the second diplexer 418 on the receive side is configured to filter the signal received from the output node before providing the filtered signal to the low noise amplifiers 406 and 408. To remove interference that may generate unwanted IMD (intermodulation distortion) components, the second diplexer 418 can be configured to remove RF signals at frequencies in the near vicinity (from the band edges). Thanks to the additional rejection of the receive filter forming diplexer 218, the insertion loss of the diplexer is relatively higher than that of a diplexer where these rejections are not performed.

[0128] Compared to the receive path, the rejection specifications and / or design constraints of the first diplexer 416 on the transmit side may be relatively loose. Thus, compared to the second diplexer 418 on the receive side, the first diplexer 416 on the transmit side can be configured with a significantly lower insertion loss, thereby improving the system efficiency of the RF front end 310.

[0129] In addition, compared to the embodiment of FIG. 7A, the embodiment of FIG. 7B has different arrangements of the first transceiver switch 410 and the second transceiver switch 412. That is, in the embodiment of FIG. 7B, the first transceiver switch 410 and the second transceiver switch 412 are located between the first diplexer 416 and the second diplexer 418 and the output node, while in the embodiment of FIG. 7A, the first transceiver switch 410 and the second transceiver switch 412 are located between the diplexer 414 and the first power amplifier 402 and the second power amplifier 404, and between the diplexer 414 and the first low noise amplifier 406 and the second low noise amplifier 408.

[0130] The configuration of FIG. 7B may be used in the 5G UHB (ultra-wideband) RF front end 310. For example, instead of using one diplexer for both the transmission path and the reception path as shown in FIG. 7A, the first diplexer 416 and the second diplexer 418 can be separated for the transmission path and the reception path.

[0131] FIG. 7C is a diagram showing still another exemplary RF front end 310 portion for two bands according to an aspect of the present disclosure. In this embodiment, the RF front end 310 includes a first power amplifier 402, a second power amplifier 404, a first low noise amplifier 406, a second low noise amplifier 408, a first diplexer 416, a second diplexer 418, and an SP4T (single-pole four-throw) switch 420.

[0132] The embodiment of FIG. 7C may be used in a situation where simultaneous operation of the first band and the second band is not required. For example, when simultaneous operation of the first band and the second band is not required, the SP4T switch 420 can be used instead of the first transceiver switch 410 and the second transceiver switch 412. By using the SP4T switch 420 as shown in FIG. 7C, the insertion loss can be reduced compared to the embodiment of FIG. 7B, so the performance in both the reception mode and the transmission mode is improved.

[0133] Figure 7D is a diagram showing yet another exemplary RF front - end 310 portion for two bands according to an aspect of the present disclosure. In this embodiment, the RF front - end 310 includes a first power amplifier 402, a second power amplifier 404, a first low - noise amplifier 406, a second low - noise amplifier 408, a first diplexer 416, a second diplexer 418, and a 2 - pole 4 - throw (2P4T) switch 422.

[0134] Using the embodiment of Figure 7D, for example, asynchronous operation may be enabled between the first band and the second band by replacing the SP4T switch 420 with a 2P4T switch 422. In this embodiment, band 1 (e.g., n77) may be in the TX mode, and at the same time, band 2 (e.g., n79) may be in the RX mode. Such asynchronous operation is prevalent in many current and future 5G networks.

[0135] Figure 8 is a diagram showing an exemplary RF front - end 310 portion for three bands according to an aspect of the present disclosure. In a particular embodiment, the RF front - end 310 may be configured to transmit / receive RF signals of two mid - bands (e.g., band B34 and band B39) and one wide - band (e.g., band n41).

[0136] The RF front - end 310 of Figure 8 includes a mid - band power amplifier 502, a wide - band power amplifier 504, a mid - band low - noise amplifier 506, a wide - band low - noise amplifier 508, a first SPDT switch 510, a second SPDT switch 512, a first triplexer 514, a second triplexer 516, and a 2P6T switch 518.

[0137] When the bands are in a specific combination, the wide - band may not need to be synchronized with a specific mid - band. For example, the operation of band n41 may not need to be synchronized with the mid - band anchor bands B34 and B39. However, since it may be possible for the reception period and the transmission period of the TDD frame to overlap, the 2P6T switch 518 includes two poles to enable this overlap.

[0138] To enable asynchronous operation between the medium band and the wide band, the first triplexer 514 on the transmission path and the second triplexer 516 on the receiving side can be separated. However, the 2P6T switch has two poles to enable simultaneous transmit and receive operation.

[0139] FIG. 9A is a diagram showing an exemplary RF front-end 310 portion for one band according to an aspect of the present disclosure. As shown in FIG. 9A, the RF front-end 310 includes a power amplifier 602, a low-noise amplifier 604, a transmit / receive switch 606, and a band-pass filter 608.

[0140] FIG. 9B is a diagram showing another exemplary RF front-end 310 portion for one band according to an aspect of the present disclosure, in which separate filters are provided for the transmission path and the reception path. As shown in FIG. 9B, the RF front-end 310 includes a power amplifier 602, a low-noise amplifier 604, a transmit filter 610, a receive filter 612, and a switch 614. Compared with FIG. 9A, instead of using one filter 608 for both the transmission path and the reception path, the embodiment of FIG. 9B separates the filter into a transmit filter 610 and a receive filter 612. By separating the transmit filter 610 and the receive filter 612 in this way, the same improvements as those described above in connection with FIG. 7B (for example, improvement of blocks on the reception path and reduction of insertion loss on the transmission path) become possible.

[0141] In certain embodiments, each band (e.g., all TDD LTE / NR bands) for a given RF communication system can be implemented using the layout described in connection with FIG. 9B.

[0142] However, it is also possible to reduce the implementation size and cost by combining at least a part of the receiving filter and the transmitting filter for a specific band into one. FIG. 9C is a diagram showing an exemplary RF front - end 310 portion for one band according to an aspect of the present disclosure. As shown in FIG. 9A, the RF front - end 310 includes a power amplifier 602, a low - noise amplifier 604, a transmitting filter 610, a receiving filter 612, a switch 614, and a common filter 616. By providing the common filter 616 on the shared path between the switch 614 and the output node, it is not necessary to duplicate the components of the common filter 616 in each of the transmitting filter 610 and the receiving filter 612. Thus, compared with the embodiment of FIG. 9B, the size of the entire RF front - end 310 can be reduced. Furthermore, by having separate transmitting filter 610 and receiving 612, the advantages associated with using separate filters can also be realized in this embodiment.

[0143] FIG. 10A is a diagram showing an exemplary RF front - end 310 portion for one band according to an aspect of the present disclosure. The RF front - end 310 shown in FIG. 10A includes a power amplifier 702, a low - noise amplifier 704, a transmitting filter 706, a receiving filter 708, a first switch 710, a second switch 712, a first auxiliary filter 714, a second auxiliary filter 716, and a common filter 718.

[0144] The common filter 718 performs a function similar to that of the common filter 616 in FIG. 9C with respect to the shared path between the second switch 712 and the output node. That is, since it is not necessary to duplicate the components of the common filter 718 in each of the transmitting filter 796 and the receiving filter 708, compared with the embodiment of FIG. 9B, the size of the entire RF front - end 310 can be reduced.

[0145] In the embodiments of FIGS. 9B and 9C, the switch 614 enables the RF front end 310 to select dynamic changes in signal path filtering (e.g., select either the transmit filter 610 on the transmit path or the receive filter 612 on the receive path). In contrast, in FIG. 10A, the first switch 710 and the second switch 712 are connected to more dynamically reconfigure the transmit filter and the receive filter more complexly by switching to one of the first auxiliary filter 714 and the second auxiliary filter 716 and connecting it to the signal path. In the embodiment of FIG. 10A, the first auxiliary filter 714 and the second auxiliary filter 176 may be implemented as shunt filters connected to ground to remove a specific portion of the RF spectrum. The first auxiliary filter 714 and the second auxiliary filter 716 are switched to form part of the transmit path and the receive path, and may have frequency characteristics that are completely different from those of the transmit filter 706 and the receive filter 708, not only in terms of the center frequency.

[0146] FIG. 10B is a diagram showing another exemplary RF front end 310 portion for one band according to an aspect of the present disclosure. The RF front end 310 shown in FIG. 10B includes a power amplifier 702, a low noise amplifier 704, a transmit filter 706, a receive filter 708, a first switch 710, a second switch 712, a first auxiliary filter 714, a second auxiliary filter 716, and a common filter 718.

[0147] In the embodiment of FIG. 10B, the first auxiliary filter 714 and the second auxiliary filter 716 are switched to form part of the transmit path and the receive path, and these filters may be implemented as shunt notch filters.

[0148] When the RF front-end 310 of FIG. 10B is implemented for band B41, during the transmission period, it may be switched to the first auxiliary filter 714 and connected to the transmission path, and may have a notch at the frequency of the WiFi 2.4GHz communication frequency so as to surely suppress the emission of B41 to WiFi below the threshold level and surely prevent the WiFi radio waves mixed with the transmitters in the B41 band from interfering. Continuing to refer to the embodiment of band B41, during the reception period, it may be switched to the second auxiliary filter 716 and connected to the reception path, and may have a notch at the frequency of the B39 band so as to sufficiently attenuate the B39 transmitter and surely prevent saturation or IMD from occurring in the low-noise amplifier 704 of B41.

[0149] Summary Unless required by the context, throughout the description and claims, words such as "comprise", "comprising", etc. are to be construed in an inclusive sense, i.e., in the sense of "including, but not limited to", as opposed to an exclusive or exhaustive sense. The word "coupled" as used throughout this specification refers to two or more elements that are either directly connected or connected via one or more intermediate elements. Similarly, the word "connected" as used throughout this specification refers to two or more elements that are either directly connected or connected via one or more intermediate elements. In addition, words such as "herein", "above", "below", and words with similar meanings, when used in this application, refer to the entire application rather than a particular location in the application. Where circumstances permit, words used in the singular or plural in the above detailed description may include the singular or plural respectively. The word "or" in relation to an enumeration consisting of two or more items includes any of the items in the enumeration; all of the items in the enumeration; and any combination of the items in the enumeration.

[0150] Also, in particular, phrases expressing conditions used in this specification such as "can", "could", "might", "can", "e.g.", "for example", "such as", etc., unless specifically stated otherwise or interpreted as used in the context, do not, generally speaking, convey the meaning that a particular embodiment includes a particular function, element and / or state and other embodiments do not. Thus, such phrases expressing conditions do not, generally speaking, imply that a function, element and / or state is necessarily required in one or more embodiments, nor do they imply that one or more embodiments necessarily include the logic for determining whether to include or implement these functions, elements and / or states in a particular embodiment, regardless of the input or instructions by the author.

[0151] The detailed description of the above embodiments of the present invention is not exhaustive and does not limit the invention to the exact expressions disclosed previously. Specific embodiments and examples of the present invention have been described above for illustration purposes, but various equivalent modifications recognized by those skilled in the art are possible within the scope of the present invention. For example, although a process or block is presented in a given order, in another embodiment, the routine having steps may be executed in a different order, a method having blocks in a different order may be adopted, or a part of the process or block may be deleted, moved, added, subdivided, combined, and / or modified. Each of these processes or blocks may be implemented in various different ways. Also, although a process or block may be shown to be executed continuously, it may instead be executed in parallel or at different times.

[0152] The teachings of the present invention shown in this specification are applicable not only to the systems described above but also to other systems. Further embodiments can be provided by combining the elements and operations of the various embodiments described above.

[0153] While specific embodiments of the present invention have been described, these embodiments are presented by way of example only and do not limit the scope of the present disclosure. In fact, the novel methods and systems described herein may be embodied in various other forms, and furthermore, various omissions, substitutions, and changes may be made to the forms of the methods and systems described herein without departing from the gist of the present disclosure. The appended claims and their equivalents include forms or changes that are included in the scope and gist of the present disclosure.

Claims

Claim 1 At least one power amplifier configured to amplify a transmission high-frequency signal within a first frequency range; At least one low-noise amplifier configured to receive a reception high-frequency signal within a second frequency range different from the first frequency range; An output node coupled to an antenna; At least one switch configured to selectively couple the output node to the at least one power amplifier during a transmission period and to the at least one low-noise amplifier during a reception period; At least one transmission filter coupled between the power amplifier and the at least one switch; At least one reception filter coupled between the low-noise amplifier and the at least one switch; A common filter coupled between the at least one switch and the output node, the common filter including one or more components configured to filter one or more frequencies commonly filtered in the first frequency range and the second frequency range, the common filter being configured as a band-pass filter for the first frequency range together with the at least one transmission filter, and the common filter being configured as a band-pass filter for the second frequency range together with the at least one reception filter; The at least one power amplifier includes a plurality of power amplifiers, and the at least one low-noise amplifier includes a plurality of low-noise amplifiers, a high-frequency front-end system. Claim 2 The front-end system according to claim 1, further comprising a first multiplexer including the at least one transmission filter and a second multiplexer including the at least one reception filter, the at least one transmission filter including a plurality of transmission filters, and the at least one reception filter including a plurality of reception filters. Claim 3 The front-end system according to claim 2, wherein the at least one switch is further configured to selectively couple one of the first multiplexer and the second multiplexer to the output node. Claim 4 A front-end system according to claim 1, further comprising a first filter bank including the at least one transmission filter and a second filter bank including the at least one reception filter, wherein the at least one transmission filter includes a plurality of transmission filters, and the at least one reception filter includes a plurality of reception filters.

5. The front-end system according to claim 4, wherein the at least one switch is further configured to selectively couple one of the transmission filters and one of the reception filters to the output node simultaneously.

6. The front-end system according to claim 1, wherein the at least one power amplifier includes a first power amplifier and a second power amplifier, the at least one low-noise amplifier includes a first low-noise amplifier and a second low-noise amplifier, the at least one transmission filter includes a transmission diplexer, the at least one reception filter includes a reception diplexer, and the at least one switch includes a first switch and a second switch.

7. The front-end system according to claim 1, further comprising a transmission auxiliary filter and a reception auxiliary filter, wherein the at least one switch includes a connected first switch and a second switch, and the second switch is configured to selectively couple the transmission auxiliary filter to the at least one power amplifier during the transmission period and the reception auxiliary filter to the at least one low-noise amplifier during the reception period.

8. The front-end system according to claim 7, wherein the transmission auxiliary filter and the reception auxiliary filter include shunt filters.

9. The front-end system according to claim 7, wherein the transmission auxiliary filter and the reception auxiliary filter include notch filters.

10. A mobile device, an antenna configured to transmit a high-frequency signal to a base station, a front-end system coupled to the antenna and configured to transmit and receive the high-frequency signal from the antenna, the front-end system comprising: at least one power amplifier configured to amplify a transmitted high-frequency signal within a first frequency range; at least one low-noise amplifier configured to receive a received high-frequency signal within a second frequency range different from the first frequency range; Optionally, at least one switch configured to selectively couple the antenna to the at least one power amplifier during a transmission period and to the at least one low-noise amplifier during a reception period; At least one transmission filter coupled between the power amplifier and the at least one switch; At least one reception filter coupled between the low-noise amplifier and the at least one switch; And a common filter coupled between the at least one switch and the antenna, the common filter including one or more components configured to filter one or more frequencies that are commonly filtered in the first frequency range and the second frequency range, the common filter being configured as a band-pass filter for the first frequency range together with the at least one transmission filter, and the common filter being configured as a band-pass filter for the second frequency range together with the at least one reception filter; The at least one power amplifier includes a plurality of power amplifiers, and the at least one low-noise amplifier includes a plurality of low-noise amplifiers, a mobile device.

11. The front-end system further includes a first multiplexer including the at least one transmission filter and a second multiplexer including the at least one reception filter, the at least one transmission filter including a plurality of transmission filters, and the at least one reception filter including a plurality of reception filters, the mobile device according to claim 10.

12. The at least one switch is further configured to selectively couple one of the first multiplexer and the second multiplexer to the antenna, the mobile device according to claim 11.

13. The front-end system further includes a first filter bank including the at least one transmission filter and a second filter bank including the at least one reception filter, the at least one transmission filter including a plurality of transmission filters, and the at least one reception filter including a plurality of reception filters, the mobile device according to claim 10.

14. The mobile device according to claim 13, wherein the at least one switch is further configured to selectively couple one of the transmission filters and one of the reception filters to the antenna simultaneously.

15. The mobile device according to claim 10, wherein the at least one power amplifier includes a first power amplifier and a second power amplifier, the at least one low noise amplifier includes a first low noise amplifier and a second low noise amplifier, the at least one transmission filter includes a transmit diplexer, the at least one reception filter includes a receive diplexer, and the at least one switch includes a first switch and a second switch.

16. A method for operating a radio frequency front-end system, comprising: During a transmission period, coupling at least one power amplifier to an antenna via at least one switch, the switch being coupled to the at least one power amplifier via at least one transmission filter, the switch being coupled to an output node via a common filter, the at least one power amplifier being configured to amplify a transmission radio frequency signal within a first frequency range, and the method further comprising: During a reception period, coupling at least one low noise amplifier to the antenna via the at least one switch, the switch being coupled to the at least one low noise amplifier via at least one reception filter, the at least one low noise amplifier being configured to receive a received radio frequency signal within a second frequency range different from the first frequency range, and the method further comprising: Filtering one or more frequencies commonly filtered in the first frequency range and the second frequency range using one or more components of the common filter, the common filter being configured as a bandpass filter for the first frequency range together with the at least one transmission filter, and the common filter being configured as a bandpass filter for the second frequency range together with the at least one reception filter. The method, wherein the at least one power amplifier includes a plurality of power amplifiers, and the at least one low noise amplifier includes a plurality of low noise amplifiers.

17. The method according to claim 16, wherein the common filter is further coupled to the antenna via the output node.

18. The method according to claim 16, wherein the at least one power amplifier includes a plurality of power amplifiers, and the at least one low noise amplifier includes a plurality of low noise amplifiers.

19. At least one power amplifier configured to amplify a transmission high-frequency signal within a first frequency range, At least one low noise amplifier configured to receive a received high-frequency signal within a second frequency range different from the first frequency range, An output node coupled to the antenna, Optionally, at least one switch configured to selectively couple the output node to the at least one power amplifier during a transmission period and to the at least one low noise amplifier during a reception period, At least one transmission filter coupled between the power amplifier and the at least one switch, At least one reception filter coupled between the low noise amplifier and the at least one switch, A common filter coupled between the at least one switch and the output node, the common filter including one or more components configured to filter one or more frequencies that are commonly filtered in the first frequency range and the second frequency range, the common filter being configured as a band-pass filter for the first frequency range together with the at least one transmission filter, and the common filter being configured as a band-pass filter for the second frequency range together with the at least one reception filter, A transmission auxiliary filter and a reception auxiliary filter are further provided, the at least one switch includes an interlocking first switch and a second switch, and the second switch is configured to selectively couple the transmission auxiliary filter to the at least one power amplifier during the transmission period and the reception auxiliary filter to the at least one low noise amplifier during the reception period, a high-frequency front-end system.

20. The high-frequency front-end system according to claim 19, wherein the transmission auxiliary filter and the reception auxiliary filter include a shunt filter or a notch filter.

21. A mobile device, An antenna configured to transmit a high-frequency signal to a base station, A front-end system coupled to the antenna and configured to transmit and receive the high-frequency signal from the antenna, the front-end system comprising: At least one power amplifier configured to amplify a transmitted high-frequency signal within a first frequency range; At least one low-noise amplifier configured to receive a received high-frequency signal within a second frequency range different from the first frequency range; At least one switch configured to selectively couple the antenna to the at least one power amplifier during a transmission period and to the at least one low-noise amplifier during a reception period; At least one transmit filter coupled between the power amplifier and the at least one switch; At least one receive filter coupled between the low-noise amplifier and the at least one switch; A common filter coupled between the at least one switch and the antenna, the common filter including one or more components configured to filter one or more frequencies commonly filtered in the first frequency range and the second frequency range, the common filter being configured as a band-pass filter for the first frequency range together with the at least one transmit filter, and the common filter being configured as a band-pass filter for the second frequency range together with the at least one receive filter; The front-end system further comprises a transmit auxiliary filter and a receive auxiliary filter, the at least one switch includes an interlocking first switch and a second switch, the second switch being configured to selectively couple the transmit auxiliary filter to the at least one power amplifier during the transmission period and the receive auxiliary filter to the at least one low-noise amplifier during the reception period, a mobile device. **Claim 22** A method for operating a high-frequency front-end system, comprising: During a transmission period, comprising the step of coupling at least one power amplifier to an antenna via at least one switch, said switch being coupled to said at least one power amplifier via at least one transmission filter, said switch being coupled to an output node via a common filter, said at least one switch including a first switch and a second switch that operate in conjunction, said at least one power amplifier being configured to amplify a transmission high-frequency signal within a first frequency range, the method further comprising During a reception period, comprising the step of coupling at least one low-noise amplifier to the antenna via said at least one switch, said switch being coupled to said at least one low-noise amplifier via at least one reception filter, said at least one low-noise amplifier being configured to receive a received high-frequency signal within a second frequency range different from said first frequency range, the method further comprising Filtering, using one or more components of said common filter, one or more frequencies that are commonly filtered in said first frequency range and said second frequency range, said common filter being configured as a band-pass filter for said first frequency range together with said at least one transmission filter, said common filter being configured as a band-pass filter for said second frequency range together with said at least one reception filter Selectively coupling, via said second switch, a transmission auxiliary filter to said at least one power amplifier during said transmission period And further comprising selectively coupling, via said second switch, said reception auxiliary filter to said at least one low-noise amplifier during said reception period. A method Claims 23 A high-frequency front-end system comprising At least one power amplifier configured to amplify a transmission high-frequency signal, and at least one low-noise amplifier configured to receive a received high-frequency signal, at least one of said transmission high-frequency signal and said received high-frequency signal operating in a frequency band adjacent to the frequency of WiFi communication, and further A first switch configured to selectively couple an output node coupled to an antenna to said at least one power amplifier during a transmission period and to said at least one low-noise amplifier during a reception period At least one transmission filter coupled between the power amplifier and at least one switch, and at least one reception filter coupled between the low noise amplifier and the at least one switch, A transmission auxiliary filter and a reception auxiliary filter, wherein at least one of the transmission auxiliary filter and the reception auxiliary filter includes a notch at the frequency of the WiFi communication, and further, Optionally, a second switch configured to couple the transmission auxiliary filter to the at least one power amplifier and the at least one transmission filter during the transmission period, and to couple the reception auxiliary filter to the at least one low noise amplifier and the at least one reception filter during the reception period. A high-frequency front-end system.

24. The front-end system according to claim 23, wherein the first switch and the second switch are connected.

25. The front-end system according to claim 23, further comprising a common filter coupled between the first switch and the output node.

26. The front-end system according to claim 23, wherein the at least one power amplifier includes a plurality of power amplifiers, and the at least one low noise amplifier includes a plurality of low noise amplifiers.

27. The front-end system according to claim 23, wherein the transmission auxiliary filter and the reception auxiliary filter include a shunt filter.

28. The front-end system according to claim 27, wherein the shunt filter is configured to remove a predetermined portion of the RF spectrum.

29. The front-end system according to claim 23, wherein the transmission auxiliary filter and the reception auxiliary filter include a notch filter.

30. The front-end system according to claim 23, wherein the transmission auxiliary filter and the reception auxiliary filter are completely different from the at least one transmission filter and the at least one reception filter in terms of center frequency and frequency characteristics.

31. The second switch is further configured to dynamically reconfigure the at least one transmit filter and the at least one receive filter by switching to one of a first auxiliary filter and a second auxiliary filter and connecting it to a signal path between at least one power amplifier, the at least one low noise amplifier, and the output node. The front-end system according to claim 23.

32. A mobile device, An antenna configured to transmit a high-frequency signal to a base station, A front-end system coupled to the antenna and configured to transmit and receive the high-frequency signal from the antenna, the front-end system comprising: At least one power amplifier configured to amplify a transmitted high-frequency signal, At least one low noise amplifier configured to receive a received high-frequency signal, A first switch configured to selectively couple the antenna to the at least one power amplifier during a transmission period and to the at least one low noise amplifier during a reception period, At least one transmit filter coupled between the power amplifier and at least one switch, At least one receive filter coupled between the low noise amplifier and the at least one switch, A transmit auxiliary filter, A receive auxiliary filter, And a second switch configured to selectively couple the transmit auxiliary filter to the at least one power amplifier and the at least one transmit filter during the transmission period and to couple the receive auxiliary filter to the at least one low noise amplifier and the at least one receive filter during the reception period. At least one of the transmit auxiliary filter and the receive auxiliary filter includes a notch at a frequency of WiFi communication, and at least one of the transmitted high-frequency signal and the received high-frequency signal operates in a frequency band adjacent to the frequency of the WiFi communication. A mobile device.

33. The mobile device according to claim 32, wherein the first switch and the second switch are connected.

34. The mobile device according to claim 32, wherein the front-end system further includes a common filter coupled between the first switch and an output node.

35. The at least one power amplifier includes a plurality of power amplifiers, and the at least one low noise amplifier includes a plurality of low noise amplifiers, the mobile device according to claim 32.

36. The transmission auxiliary filter and the reception auxiliary filter include a shunt filter, the mobile device according to claim 32.

37. The shunt filter is configured to remove a predetermined portion of the RF spectrum, the mobile device according to claim 36.

38. The transmission auxiliary filter and the reception auxiliary filter include a notch filter, the mobile device according to claim 32.

39. The transmission auxiliary filter and the reception auxiliary filter are completely different from the at least one transmission filter and the at least one reception filter in terms of center frequency and frequency characteristics, the mobile device according to claim 32.

40. A method of operating a high frequency front end system, comprising: During a transmission period, coupling at least one power amplifier to an antenna via a first switch, the first switch being coupled to the at least one power amplifier via at least one transmission filter, the at least one power amplifier amplifying a transmission high frequency signal during the transmission period, the method further comprising: During a reception period, coupling at least one low noise amplifier to the antenna via the first switch, the first switch being coupled to the at least one low noise amplifier via at least one reception filter, the at least one low noise amplifier receiving a reception high frequency signal during the reception period, at least one of the transmission high frequency signal and the reception high frequency signal operating in a frequency band adjacent to the frequency of Wi-Fi communication, the method further comprising: During the transmission period, coupling a transmission auxiliary filter to the at least one power amplifier and the at least one transmission filter via a second switch; and During the reception period, coupling a reception auxiliary filter to the at least one low noise amplifier and the at least one reception filter via the second switch, at least one of the transmission auxiliary filter and the reception auxiliary filter including a notch at the frequency of the Wi-Fi communication.

41. The method according to claim 40, wherein a common filter is coupled between the first switch and the antenna.

42. The method according to claim 40, wherein the at least one power amplifier includes a plurality of power amplifiers, and the at least one low noise amplifier includes a plurality of low noise amplifiers.

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