HK1216467B - Transmit front end module for dual antenna applications - Google Patents

Description

Transmit front-end module for dual-antenna applications

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No. 62/036,879, filed on August 13, 2014, entitled “TRANSMIT FRONT END MODULE FOR DUAL ANTENNA APPLICATIONS,” the disclosure of which is hereby expressly incorporated herein by reference in its entirety.

Technical Field

The present application relates to RF modules used in cellular wireless systems.

Background Art

In cellular wireless systems, two antennas can be used to transmit and receive signals over a large cellular frequency band. RF front-end modules can be used to manage these signals.

Summary of the Invention

According to some embodiments, the present application relates to a front-end module, comprising: a packaging substrate configured to accommodate multiple components; a first input port and a second input port configured to receive corresponding radio frequency (RF) signals for amplification; and a first antenna port and a second antenna port configured to output the amplified RF signals to corresponding antennas. The front-end module also includes: a front-end circuit implemented between the input port and the antenna port, the front-end circuit including a power amplifier (PA) for each of the first and second input ports, the front-end circuit also including an antenna switch configured to route the amplified RF signal from each PA to its corresponding antenna port, and the front-end circuit also including a coupler implemented between the antenna switch and the antenna port, the coupler configured to detect the output power of the amplified RF signal.

In some embodiments, the front-end circuitry of the front-end module includes substantially all components required to couple first and second frequency band outputs of a transceiver to respective antennas for transmit operations involving the first and second frequency bands.

In some embodiments, the first frequency band of the front-end module is a high frequency band, and the second frequency band is a low frequency band. In some implementations, the front-end circuit of the front-end module further comprises: an output matching network implemented at the output of each of the first and second PAs.

In some embodiments, the front-end circuit of the front-end module further includes: a harmonic filter implemented at the output of each of the first and second output matching networks.

In some embodiments, the antenna switch of the front-end module includes a DPNT (double-pole N-throw) configuration, wherein the double-pole is coupled to the first and second antenna ports via the coupler. In some embodiments, the N-throw and double-pole of the antenna switch are divided into a high-band portion having an SPXT (single-pole X-throw) configuration and a low-band portion having an SPYT (single-pole Y-throw) configuration. In some embodiments, one of the X-throws of the high-band portion is connected to the output of the high-band PA, while one of the Y-throws of the low-band portion is connected to the output of the low-band PA.

In some embodiments, the coupler is implemented as an integrated passive device (IPD), and in some embodiments, the IPD includes dedicated coupler circuitry for each of the high frequency band and the low frequency band.

In some embodiments, the front-end circuit of the front-end module further includes an electrostatic discharge (ESD) protection circuit implemented between each dedicated coupler circuit and the corresponding antenna port. In some implementations, the front-end circuit of the front-end module further includes a filter implemented between each dedicated coupler circuit and the corresponding antenna port.

According to some embodiments, the present application relates to a radio frequency (RF) device comprising a transceiver configured to process RF signals. The RF device further comprises a front-end module in communication with the transceiver, wherein the front-end module comprises a packaging substrate configured to house a plurality of components; a first input port and a second input port configured to receive respective RF signals for amplification; and a first antenna port and a second antenna port configured to output respective amplified RF signals. The front-end module of the RF device further comprises a front-end circuit implemented between the input port and the antenna port. The front-end circuit comprises a power amplifier (PA) for each of the first and second input ports; an antenna switch configured to route the amplified RF signal from each PA to its corresponding antenna port; and a coupler implemented between the antenna switch and the antenna port, the coupler configured to detect the output power of the amplified RF signal. The RF device further comprises a first antenna and a second antenna connected to the first and second antenna ports of the front-end module, respectively, the first and second antennas configured to transmit their respective amplified RF signals.

In some embodiments, the RF device comprises a wireless device, and in some embodiments, the wireless device is a cellular telephone.

In some embodiments, the transceiver of the RF device communicates with a baseband subsystem configured to provide conversion between data and/or voice signals. In some embodiments, the baseband subsystem communicates with a user interface. In some embodiments, the front-end module of the RF device communicates with one or more low-noise amplifiers (LNAs), and amplified signals from the one or more LNAs are routed to the transceiver.

In some embodiments, the coupler of the front-end module of the RF device is implemented as an integrated passive device (IPD).

According to some embodiments, a method for manufacturing a front-end module (FEM) is disclosed. The method includes: providing a packaging substrate configured to accommodate multiple components; providing a first input port and a second input port, the first input port and the second input port being configured to receive corresponding radio frequency (RF) signals for amplification; and providing a first antenna port and a second antenna port, the first antenna port and the second antenna port being configured to output the amplified RF signals to corresponding antennas. The method also includes: incorporating a front-end circuit, the front-end circuit being implemented between the input port and the antenna port, the front-end circuit including a power amplifier (PA) for each of the first and second input ports, the front-end circuit also including an antenna switch configured to route the amplified RF signal from each PA to its corresponding antenna port, the front-end circuit also including a coupler implemented between the antenna switch and the antenna port, the coupler being configured to detect the output power of the amplified RF signal.

For the purpose of summarizing this application, certain aspects, advantages and novel features of the present invention have been described herein. It should be understood that it is not necessary to realize all of these advantages according to any specific embodiment of the present invention. Thus, the present invention may be implemented or realized in a manner that realizes or optimizes an advantage or a group of advantages as taught herein, without the need to realize other advantages as may be taught or suggested herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 illustrates an example block diagram of a radio frequency module for supporting two or more antennas according to some embodiments.

FIG2 illustrates an example block diagram of a radio frequency module for supporting two or more antennas according to some embodiments.

FIG3 illustrates an example switching circuit topology according to some embodiments.

FIG4 illustrates an example switching circuit topology according to some embodiments.

FIG. 5 illustrates an example coupler circuit implemented as an integrated passive device in accordance with some embodiments.

FIG. 6 illustrates an example coupling assembly having first and second coupling circuits according to some embodiments.

FIG. 7 illustrates an example coupling assembly including coupling circuits implemented in a chain configuration, according to some embodiments.

FIG8 illustrates an example block diagram of a wireless device in accordance with some embodiments.

DETAILED DESCRIPTION

The headings provided herein, if any, are for convenience only and do not necessarily affect the scope or meaning of the claimed invention.

As design requirements and expectations become stronger, cellular wireless systems are becoming increasingly complex. As the LTE market grows, cellular frequency bands are expanding, for example, from 700 MHz to 2700 MHz. This expansion leads to greater complexity in wireless systems.

For example, in traditional handset designs, a single antenna may be used to support both cellular transmit and receive systems. However, OTA (over-the-air) transmission capabilities may be limited by antenna efficiency across the frequency band. Typically, high frequencies (e.g., 2.5 GHz-2.7 GHz) can be a problematic range. Due to the wideband matching requirements on a given antenna, it is often impossible to fully optimize matching in the high frequency band, resulting in reduced efficiency.

Due to this lower efficiency, the power amplifier needs to output higher power to meet the TRP (total radiated power) requirement. As a result, the system consumes more power and the linearity is usually degraded.

Some wireless designs are incorporating dedicated antennas for high-frequency bands (or groups). However, if the TX FEM (Transmit Front-End Module) only supports a single antenna, additional components must be implemented to accommodate this dedicated antenna. For example, to enable dual-antenna applications, the wireless device would need to add an additional switch between the TX FEM and the additional dedicated antenna feed, thereby increasing BOM (Bill of Materials) cost and design complexity.

1 depicts a radio frequency (RF) module 100 including various components for accommodating such additional antennas. Although described in the context of a dual antenna configuration, it will be appreciated that one or more features of the present disclosure may also be implemented for RF systems having more than two antennas.

In FIG1 , RF module 110 is shown to include PA 102, antenna switch 104, and coupler 106. Additional details regarding these components are described in greater detail herein. RF module 110 is shown to receive first and second inputs (RFin1, RFin2) and generate first and second outputs (RFout1, RFout2) for transmission via their respective antennas (not shown in FIG1 ). In some embodiments, substantially all of PA 102, antenna switch 104, and coupler 106 may be implemented in RF module 100.

FIG2 shows an RF module 100 that can be a more specific example of the RF module 100 of FIG1 . In FIG2 , the RF module is depicted in the example context of a TXFEM (transmit front-end module). However, it will be appreciated that one or more features of the present application can be implemented in other types of RF modules.

In the example of FIG2 , TX FEM 100 is shown as including a package substrate 110 configured to house and support a plurality of components. For example, such a package substrate may include a laminate substrate, a ceramic substrate, etc. The PA component is generally designated 102; the antenna switch component is generally designated 104; and the coupler component is generally designated 106.

By way of example, the PA component 102 is shown as including a high-band (HB) amplification path and a low-band (LB) amplification path. RF signals associated with the HB path can be received through an input node 120 as HB_RFin and amplified by one or more stages of a HB power amplifier (PA) 122. RF signals associated with the LB path can be received through an input node 140 as LB_RFin and amplified by one or more stages of a LB power amplifier (PA) 142.

For example, the amplified output of HB PA 122 may pass through matching network 124 and harmonic filter 126 and be provided to antenna switch 104. Similarly, the amplified output of LB PA 142 may pass through matching network 144 and harmonic filter 146 and be provided to antenna switch 104.

In some embodiments, the antenna switch 104 may include a high-band portion 128 and a low-band portion 148. For example, if the antenna switch 104 has a DPNT (double-pole N-throw) configuration, which includes two poles for accommodating two antennas, the high-band portion 128 may have an SPXT (single-pole X-throw) configuration, while the low-band portion 148 may have an SPYT (single-pole Y-throw) configuration. In the example shown in FIG2 , the value of X is 3, and the value of Y is 3. It will be understood that other values of X and Y may also be implemented.

2 , a single throw of the high-band portion 128 of the antenna switch 104 is shown coupled to a first antenna port 166 via a path 130, a coupler 160, a path 162, and an ESD/filter circuit 164. Similarly, the throw of the low-band portion 148 of the antenna switch 104 is shown coupled to a second antenna port 176 via a path 150, a coupler 160, a path 172, and an ESD/filter circuit 174. The output of the coupler 160 is shown provided to a node 182 (CPL_O) via a path 180.

2 , one of the throws in the high-band portion 128 of the antenna switch 104 is shown connected to the harmonic filter 126 to receive the amplified HB signal. The other throws are shown as being used for RX functionality of the high-band associated with HB_RFin and/or TX/RX functionality of other high-bands.

Similarly, one of the throws in the low-band portion 148 of the antenna switch 104 is shown connected to the harmonic filter 146 to receive the amplified LB signal. The other throws are shown as being used for RX functionality of the low band associated with LB_RFin and/or TX/RX functionality of other low bands.

In some embodiments, coupler 160 can be implemented as an integrated passive device (IPD). In some embodiments, a single IPD can be configured to include two dedicated coupler circuits for high-band and low-band channels. In some embodiments, a first IPD can be configured to include a first coupler circuit for the high-band, and a separate second IPD can be configured to include a second coupler circuit for the low-band.

In some embodiments, the coupler 160 can be configured to detect the transmit power of either or both the high-band signal and the low-band signal.

2 , TX FEM 100 is shown as also including a controller component 190 configured to effectuate the operation of some or all components of module 100. Although not shown, module 100 may also include circuits, connections, etc. configured to, for example, provide power, bias signals, etc.

In some embodiments, the PAs 122, 142 may be implemented in a suitable configuration for RF applications, such as cellular applications. For example, GaAs (Gallium Arsenide) based devices, such as HBT devices, or silicon based devices may be utilized.

In some embodiments, the antenna switch 104 can be implemented in a suitable configuration for RF applications such as cellular applications. For example, silicon-on-insulator (SOI) technology can be implemented to implement the various switch FETs.

In some embodiments, the various components associated with the PA component 102, the antenna switch 104, and the coupler component 106 can be implemented as a semiconductor die. Such a die can be packaged as a wirebond type, a flip-chip type, or any combination of known packaging types.

In some embodiments, a module such as a TX FEM as described herein can integrate substantially all components needed or desired in a phone design, from the transceiver output to the corresponding antenna. As described herein, such a module can include power amplifier components, corresponding matching networks, harmonic filters, T/R switches, couplers, and ESD (electrostatic discharge) protection networks.

In some embodiments, the aforementioned modules can be implemented in very compact sizes. For example, a TX FEM having one or more features as described herein can have lateral dimensions of approximately 5.5 mm x 5.3 mm. In addition to the compact size of the TX FEM, consolidating one or more components into the module can further significantly reduce the area required on the phone board for the functions provided by the TX FEM. Furthermore, the BOM cost associated with such TX FEM functions can also be significantly reduced.

In some embodiments, structures, devices, and/or circuits having one or more features described herein may be included in an RF device such as a wireless device. Such structures, devices, and/or circuits may be implemented directly in the wireless device, in one or more modules as described herein, or in some combination thereof. In some embodiments, such wireless devices may include, for example, cellular phones, smartphones, handheld wireless devices with or without telephone functionality, wireless tablets, wireless routers, wireless access points, wireless base stations, and the like.

FIG3 illustrates an example switch topology that can be implemented for each of the switches 128 and 148 of FIG2 . In the example of FIG3 , a common pole is shown coupled to each of the three throws (Throw_1, Throw_2, Throw_3) via corresponding switch arms 200 a, 200 b, 200 c (Series_1, Series_2, Series_3). A node associated with each throw can be coupled to ground via a shunt switch arm. Accordingly, the first throw is shown coupled to ground via a first shunt switch arm 202 a (Shunt_1), the second throw is shown coupled to ground via a second shunt switch arm 202 b (Shunt_2), and the third throw is shown coupled to ground via a third shunt switch arm 202 c (Shunt_3).

In some embodiments, the aforementioned example switch topology can provide an example SP3T switch function by appropriately controlling the switch arms. For example, when Throw_1 is connected to a Pole, the Series_1 switch arm can be turned on, while the Series_2 and Series_3 switch arms can be turned off. For this routing configuration (Throw_1 to Pole), the first bypass arm (Shunt_1) can be turned off, while the second and third bypass arms (Shunt_2, Shunt_3) can be turned on. A similar switch configuration can be implemented when signal routing between Throw_2 and a Pole or Throw_3 and a Pole is desired. In many RF applications, this switch configuration can provide improved isolation between different channels associated with, for example, switches 128 or 148.

FIG4 shows a more specific example of the switch topologies 128 and 124 of FIG3. In the example of FIG4, each of the switch arms 200a, 200b, and 200c (Series_1, Series_2, and Series_3 in FIG3) can be implemented as a plurality of field effect transistors (FETs) 204 arranged in a stack. Similarly, each of the bypass arms 202a, 202b, and 202c (Shunt_1, Shunt_2, and Shunt_3 in FIG3) can be implemented as a plurality of field effect transistors (FETs) 206 arranged in a stack.

In some embodiments, the aforementioned stack of FETs 204, 206 can be operated by, for example, providing appropriate bias signals to the gates and bodies of the FETs. It will be appreciated that the number of FETs in the stack of switch arms (200a, 200b, or 200c) can be the same as or different from the number of FETs in the stack of bypass arms (202a, 202b, or 202c).

In some embodiments, for example, the switch arms 200a, 200b, and 200c (Series_1, Series_2, and Series_3 in FIG. 3 ) and the bypass arms 202a, 202b, and 202c (Shunt_1, Shunt_2, and Shunt_3 in FIG. 3 ) can be implemented as silicon-on-insulator (SOI) devices. In some embodiments, each of the switches 128 and 148 of FIG. 2-4 can be implemented on a common SOI wafer. In some embodiments, the switch 128 of FIG. 2-4 can be implemented on a first SOI wafer, and the switch 148 of FIG. 2-4 can be implemented on a second SOI wafer. It will be appreciated that such switches 128 and 148 can also be implemented in other configurations.

FIG5 depicts a more detailed example of coupler 160 of FIG2 . FIG5 illustrates that, in some embodiments, coupler 160 can be implemented as an integrated passive device (IPD) having various circuits and components on substrate 210. Such an IPD coupler can include input pins 212, 222 coupled to corresponding output pins 216, 226 via corresponding signal paths 214, 224. For example, input pins 212, 222 can be configured to connect to signal paths 130, 150, respectively, of FIG2 . Similarly, output pins 216, 226 can be configured to connect to signal paths 162, 172 of FIG2 .

5 , IPD coupler 160 may also include coupling elements 218, 228 implemented in association with respective signal paths 214, 224. Such coupling elements may be components of a coupling assembly generally depicted as 230. Non-limiting examples of how such a coupling assembly may be configured are shown in FIG6 and 7 .

FIG6 illustrates that, in some embodiments, the coupling assembly 230 of FIG5 may include first and second coupling circuits that are generally independent of each other. For example, the first coupling circuit may include input and output pins 232, 234 connected to respective ends of the first coupling element 218. Similarly, the second coupling circuit may include input and output pins 242, 244 connected to respective ends of the second coupling element 228.

7 shows that, in some embodiments, the coupling assembly 230 of FIG5 may include a coupling circuit implemented in a chain configuration. For example, such a coupling circuit may include an input pin 252 connected to an output pin 254 via first and second coupling elements 218, 228 in a daisy-chain configuration.

It will be appreciated that other configurations may also be implemented for the coupler 160 of FIG. 5 .

Figure 8 schematically depicts an example wireless device 300 having one or more advantageous features described herein. In some embodiments, such advantageous features may be implemented in a module 100, such as a front end (FE) module.

Each PA in the PA component 102 can receive its corresponding RF signal from a transceiver 310, which can be configured and operated in a known manner to generate RF signals to be amplified and transmitted, and to process the received signals. The transceiver 310 is shown as interacting with a baseband subsystem 308, which is configured to provide conversion between data and/or voice signals for a user and RF signals for the transceiver 310. The transceiver 310 is also shown as being connected to a power management component 306, which is configured to manage the power used to operate the wireless device 300. Such power management can also control the operation of the baseband subsystem 308 and other components of the wireless device 300.

The baseband subsystem 308 is shown connected to the user interface 302 to facilitate various inputs and outputs of voice and/or data to and from the user. The baseband subsystem 308 may also be connected to the memory 304, which is configured to store data and/or instructions to facilitate the operation of the wireless device and/or to provide storage of information to the user.

In the example wireless device 300, the front-end module 100 may include a PA component 102, an antenna switch 104, and a coupler component 106 as described herein. In FIG8 , some received signals are shown as being routed from the front-end module 100 to one or more low noise amplifiers (LNAs) 312. The amplified signals from the LNAs 312 are shown as being routed to the transceiver 310.

Many other wireless device configurations can utilize one or more of the features described herein. For example, a wireless device need not be a multi-band device. In another example, a wireless device can include additional antennas such as a diversity antenna, and additional connectivity features such as Wi-Fi, Bluetooth, and GPS.

According to some embodiments, the present application also provides a method for manufacturing a front-end module (FEM). The method includes: providing a packaging substrate, the packaging substrate being configured to accommodate multiple components; providing a first input port and a second input port, the first input port and the second input port being configured to receive corresponding radio frequency (RF) signals for amplification; and providing a first antenna port and a second antenna port, the first antenna port and the second antenna port being configured to output the amplified RF signals to corresponding antennas. The method also includes: incorporating a front-end circuit, the front-end circuit being implemented between the input port and the antenna port, the front-end circuit including a power amplifier (PA) for each of the first and second input ports, the front-end circuit also including an antenna switch configured to route the amplified RF signal from each PA to its corresponding antenna port, the front-end circuit also including a coupler implemented between the antenna switch and the antenna port, the coupler being configured to detect the output power of the amplified RF signal. The specific content is very clear in conjunction with the above-mentioned drawings and descriptions, and no further elaboration is required.

Unless the context clearly requires otherwise, throughout the specification and claims, the terms "comprise," "comprising," and the like are to be interpreted in an inclusive sense, as opposed to an exclusive or exhaustive sense, that is, in the sense of "including but not limited to." The term "coupled," as generally used herein, refers to two or more elements that may be connected directly or by means of one or more intermediate elements. Additionally, when used in this application, the terms "herein," "above," "below," and terms of similar meaning shall refer to this application as a whole and not to any particular parts of this application. Where the context permits, the detailed descriptions above using the singular or plural may also include the plural or singular, respectively. The term "or" when referring to a list of two or more items encompasses all of the following interpretations of that term: any item in the list, all items in the list, and any combination of items in the list.

The above detailed description of the embodiment of the present invention is not intended to be exhaustive or to limit the present invention to the precise form disclosed above. Although specific embodiments of the present invention and examples for the present invention have been described above for illustrative purposes, various equivalent modifications within the scope of the present invention are possible as will be appreciated by those skilled in the art. For example, although processes or blocks are presented in a given order, alternative embodiments may perform processes with steps in a different order, or employ systems with blocks in a different order, and some processes or blocks may be deleted, moved, added, subtracted, combined, and/or modified. Each of these processes or blocks may be implemented in a variety of ways. Similarly, although processes or blocks are sometimes shown as being performed serially, on the contrary, these processes or blocks may also be performed in parallel, or may be performed at different times.

The teachings of the invention provided herein can be applied to other systems, not necessarily the system described above.The elements and acts of the various embodiments described above can be combined to provide further embodiments.

Although some embodiments of the present invention have been described, these embodiments have been presented by way of example only and are not intended to limit the scope of this application. Indeed, the novel methods and systems described herein may be implemented in a variety of other forms; furthermore, various omissions, substitutions, and changes in the form of the methods and systems described herein may be made without departing from the spirit of this application. The accompanying drawings and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of this application.

Claims (20)

1. A front-end module (FEM), comprising: The packaging substrate is configured to accommodate multiple components; The first input port is configured to receive a first radio frequency (RF) signal for amplification. The second input port is configured to receive a second radio frequency (RF) signal for amplification. The first antenna port is configured to output a first amplified RF signal to a first antenna associated with a first frequency band; The second antenna port is configured to output a second amplified RF signal to a second antenna associated with a second frequency band; and A front-end circuit, implemented between the input port and the antenna port, includes a first power amplifier (PA) for the first input port and a second power amplifier (PA) for the second input port. The front-end circuit also includes an antenna switch configured to route a first amplified RF signal from the first PA to the first antenna port and a second amplified RF signal from the second PA to the second antenna port via a coupler implemented between the antenna switch and the antenna port. The coupler is configured to detect the output power of the first and second amplified RF signals. The antenna switch includes a first antenna switch configured as a single-pole X-throw (SPXT) for the first frequency band and a second antenna switch configured as a single-pole Y-throw (SPYT) for the second frequency band. A single pole of the first antenna switch is coupled to the X-throw via a corresponding switch arm, and a node associated with each of the X-throws is coupled to ground via a bypass switch arm. Similarly, a single pole of the second antenna switch is coupled to the Y-throw via a corresponding switch arm, and a node associated with each of the Y-throws is coupled to ground via a bypass switch arm. 2. The FEM of claim 1, wherein the front-end circuitry substantially includes all components required for coupling the first and second frequency band outputs of the transceiver to the respective antennas for transmission operations involving the first and second frequency bands. 3. The FEM of claim 1, wherein the first frequency band is a high frequency band and the second frequency band is a low frequency band. 4. The FEM of claim 3, wherein the front-end circuit further comprises: The first output matching network is implemented at the output of the first PA; and The second output matching network is implemented at the output of the second PA. 5. The FEM of claim 4, wherein the front-end circuitry further comprises: a harmonic filter implemented at the output of each of the first and second output matching networks. 6. The FEM of claim 3, wherein the single-pole of the first antenna switch is coupled to the first antenna port via the coupler, and the single-pole of the second antenna switch is coupled to the second antenna port via the coupler. 7. The FEM of claim 1, wherein the coupler comprises at least two coupling elements arranged in a daisy chain. 8. The FEM of claim 3, wherein one of the X throws of the high-frequency band portion is connected to the output of the high-frequency band PA, and one of the Y throws of the low-frequency band portion is connected to the output of the low-frequency band PA. 9. The FEM of claim 3, wherein the coupler is implemented as an integrated passive device (IPD). 10. The FEM of claim 9, wherein the IPD includes dedicated coupler circuitry for each of the high-frequency band and the low-frequency band. 11. The FEM of claim 10, wherein the front-end circuit further comprises: an electrostatic discharge (ESD) protection circuit implemented between each dedicated coupler circuit and the corresponding antenna port. 12. The FEM of claim 10, wherein the front-end circuitry further comprises: a filter implemented between each dedicated coupler circuit and the corresponding antenna port. 13. A radio frequency (RF) device, comprising: The transceiver is configured to process RF signals; A front-end module (FEM) communicates with the transceiver. The FEM includes a package substrate configured to house multiple components. The FEM also includes a first input port and a second input port. The first input port is configured to receive a first RF signal for amplification, and the second input port is configured to receive a second RF signal for amplification. The FEM further includes a first antenna port and a second antenna port. The first antenna port is configured to output the first amplified RF signal, and the second antenna port is configured to output the second amplified RF signal. The FEM also includes front-end circuitry implemented between the input ports and the antenna ports. The front-end circuitry includes a first power amplifier (PA) for the first input port and a second power amplifier (PA) for the second input port. The front-end circuitry also includes an antenna switch configured to... A coupler implemented between the antenna switch and the antenna port routes a first amplified RF signal from a first PA to the first antenna port and a second amplified RF signal from a second PA to the second antenna port. The coupler is configured to detect the output power of the first amplified RF signal and the second amplified RF signal. The antenna switch includes a first antenna switch configured as a single-pole X-throw SPXT for a first frequency band and a second antenna switch configured as a single-pole Y-throw SPYT for a second frequency band. A single pole of the first antenna switch is coupled to the X-throw via a corresponding switch arm, and a node associated with each of the X-throws is coupled to ground via a bypass switch arm. Similarly, a single pole of the second antenna switch is coupled to the Y-throw via a corresponding switch arm, and a node associated with each of the Y-throws is coupled to ground via a bypass switch arm. A first antenna and a second antenna are respectively connected to the first and second antenna ports. The first antenna is associated with the first frequency band, and the second antenna is associated with the second frequency band. The first and second antennas are configured to transmit corresponding amplified RF signals. 14. The RF device of claim 13, wherein the RF device includes a wireless device. 15. The RF device of claim 14, wherein the wireless device is a cellular phone. 16. The RF device of claim 13, wherein the transceiver communicates with a baseband subsystem configured to provide conversion between data and/or voice signals. 17. The RF device of claim 16, wherein the baseband subsystem communicates with a user interface. 18. The RF device of claim 13, wherein the FEM communicates with one or more low-noise amplifiers (LNAs), and amplified signals from the one or more LNAs are routed to the transceiver. 19. The RF device of claim 13, wherein the coupler of the FEM is implemented as an integrated passive device IPD. 20. A method for manufacturing a front-end module (FEM), the method comprising: A packaging substrate is provided, the packaging substrate being configured to accommodate a plurality of components; A first input port is configured to receive a first radio frequency (RF) signal for amplification. A second input port is provided, which is configured to receive a second radio frequency (RF) signal for amplification; A first antenna port is provided, which is configured to output a first amplified RF signal to a first antenna associated with a first frequency band; A second antenna port is configured to output a second amplified RF signal to a second antenna associated with a second frequency band; and A front-end circuit is incorporated between the input port and the antenna port. The front-end circuit includes a first power amplifier (PA) for the first input port and a second power amplifier (PA) for the second input port. The front-end circuit also includes an antenna switch configured to route a first amplified RF signal from the first PA to the first antenna port and a second amplified RF signal from the second PA to the second antenna port via a coupler implemented between the antenna switch and the antenna port. The coupler is configured to detect the output power of the first and second amplified RF signals. The antenna switch includes a first antenna switch configured as a single-pole X-throw (SPXT) for the first frequency band and a second antenna switch configured as a single-pole Y-throw (SPYT) for the second frequency band. The single pole of the first antenna switch is coupled to the X-throw via a corresponding switch arm, and a node associated with each of the X-throws is coupled to ground via a bypass switch arm. Similarly, the single pole of the second antenna switch is coupled to the Y-throw via a corresponding switch arm, and a node associated with each of the Y-throws is coupled to ground via a bypass switch arm.