KR102246674B1 - Diversity receiver front end system with post-amplifier filters - Google Patents

Abstract

A diversity receiver front end system with post-amplifier filters is disclosed. The receiving system may include a controller configured to selectively activate one or more of a plurality of paths between an input of the first multiplexer and an output of the second multiplexer. The receiving system may further include a plurality of amplifiers. Each of the plurality of amplifiers may be arranged along a corresponding one of the plurality of paths and may be configured to amplify a signal received at the amplifier. The receiving system may include a first plurality of bandpass filters. Each of the first plurality of bandpass filters may be arranged along a corresponding one of a plurality of paths at an output of a corresponding one of the plurality of amplifiers, and may be configured to filter a signal received from the bandpass filter into each frequency band.

Description

DIVERSITY RECEIVER FRONT END SYSTEM WITH POST-AMPLIFIER FILTERS

Cross-reference to related applications

This application is a U.S. Provisional Application No. 62/073,043 filed on Oct. 31, 2014, entitled "DIVERSITY RECEIVER FRONT END SYSTEM", the entire contents of each being expressly incorporated herein by reference, US Provisional Application No. 62/077,894 filed on November 10, 2014 with the name of the invention "DIVERSITY RECEIVER ARCHITECTURE HAVING PRE AND POST LNA FILTERS FOR SUPPORTING CARRIER AGGREGATION", and the name of the invention "DIVERSITY FRONT END SYSTEM WITH VARIABLE-GAIN AMPLIFIERS" US Application No. 14/727,739 filed on June 1, 2015, and US Application No. 14/735,482 filed on June 10, 2015, entitled "DIVERSITY RECEIVER FRONT END SYSTEM WITH POST-AMPLIFIER FILTERS" Insist on priority.

Technical field

The present disclosure relates generally to a wireless communication system having one or more diversity receiving antennas.

In wireless communications applications, size, cost, and performance are examples of factors that may be important for a given product. For example, to increase performance, wireless components such as diversity receive antennas and associated circuitry are becoming more popular.

In many radio-frequency (RF) applications, the diversity receiving antenna is located physically away from the main antenna. Once both antennas are used, the transceiver can process signals from both antennas to increase data throughput.

In accordance with some implementations, the present disclosure relates to a receiving system comprising a controller configured to selectively activate one or more of a plurality of paths between an input of a first multiplexer and an output of a second multiplexer. The receiving system may include a plurality of amplifiers. Each of the plurality of amplifiers may be disposed along a corresponding one of the plurality of paths and may be configured to amplify a signal received at the amplifier. The receiving system may include a first plurality of bandpass filters. Each of the first plurality of bandpass filters may be disposed along a corresponding one of a plurality of paths at the output of the corresponding one of the plurality of amplifiers, and filters the signal received from the bandpass filter into each frequency band. Can be configured to

In some embodiments, the receiving system may further include a second plurality of bandpass filters. Each of the second plurality of bandpass filters may be disposed along a corresponding one of a plurality of paths at the input of the corresponding one of the plurality of amplifiers, and filters the signal received from the bandpass filter into each frequency band. Can be configured to

In some embodiments, one of the first plurality of bandpass filters disposed along the first path and one of the second plurality of bandpass filters disposed along the first path may be complementary. In some embodiments, one of the bandpass filters disposed along the first path may attenuate frequencies below each frequency band more than frequencies above each frequency band, and a bandpass disposed along the first path. Another of the pass filters can attenuate frequencies above each frequency band more than frequencies below each frequency band.

In some embodiments, the receiving system may further include a transmission line coupled to the output of the second multiplexer and coupled to a downstream module comprising a downstream multiplexer. In some embodiments, the downstream module does not include a downstream bandpass filter. In some embodiments, the downstream multiplexer includes a sample switch. In some embodiments, the downstream module may include one or more downstream amplifiers. In some embodiments, the number of one or more downstream amplifiers may be less than the number of a plurality of amplifiers.

In some embodiments, at least one of the plurality of amplifiers may include a low noise amplifier.

In some embodiments, the receiving system may further include one or more tunable matching circuits disposed at one or more of the input of the first multiplexer and the output of the second multiplexer.

In some embodiments, the controller may be configured to selectively activate one or more of the plurality of paths based on a band select signal received by the controller. In some embodiments, the controller may be configured to selectively activate one or more of the plurality of paths by sending a splitter control signal to the first multiplexer and a combiner control signal to the second multiplexer.

In some implementations, the present disclosure is directed to a radio-frequency (RF) module that includes a packaging substrate configured to receive a plurality of components. The RF module further includes a receiving system implemented on the packaging substrate. The receiving system includes a controller configured to selectively activate one or more of the plurality of paths between the input of the first multiplexer and the output of the second multiplexer. The receiving system further includes a plurality of amplifiers. Each of the plurality of amplifiers may be disposed along a corresponding one of the plurality of paths and may be configured to amplify a signal received at the amplifier. The receiving system further includes a first plurality of bandpass filters. Each of the first plurality of bandpass filters may be disposed along a corresponding one of a plurality of paths at the output of the corresponding one of the plurality of amplifiers, and filters the signal received from the bandpass filter into each frequency band. Can be configured to

In some embodiments, the RF module may be a diversity receiver front-end module (FEM).

In some embodiments, the receiving system may further include a second plurality of bandpass filters. Each of the second plurality of bandpass filters may be disposed along a corresponding one of a plurality of paths at the input of the corresponding one of the plurality of amplifiers, and filters the signal received from the bandpass filter into each frequency band. Can be configured to

In some embodiments, the plurality of paths may include an off-module path including one of an off-module bandpass filter and a plurality of amplifiers.

In accordance with some teachings, the present disclosure relates to a wireless device comprising a first antenna configured to receive a first radio-frequency (RF) signal. The wireless device further includes a first front-end module (FEM) in communication with the first antenna. The first FEM includes a packaging substrate configured to receive a plurality of components. The first FEM further includes a receiving system implemented on the packaging substrate. The receiving system includes a controller configured to selectively activate one or more of the plurality of paths between the input of the first multiplexer and the output of the second multiplexer. The receiving system further includes a plurality of amplifiers. Each of the plurality of amplifiers may be disposed along a corresponding one of the plurality of paths and may be configured to amplify a signal received at the amplifier. The receiving system further includes a first plurality of bandpass filters. Each of the first plurality of bandpass filters may be disposed along a corresponding one of a plurality of paths at the output of the corresponding one of the plurality of amplifiers, and filters the signal received from the bandpass filter into each frequency band. Can be configured to The wireless device further includes a communication module configured to receive the processed version of the first RF signal from the output over the transmission line and generate a data bit based on the processed version of the first RF signal.

In some embodiments, the wireless device further includes a second antenna configured to receive a second radio-frequency (RF) signal and a second FEM in communication with the second antenna. The communication module may also be configured to receive a processed version of the second RF signal from the output of the second FEM and generate data bits based on the processed version of the second RF signal.

In some embodiments, the receiving system further includes a second plurality of bandpass filters. Each of the second plurality of bandpass filters may be disposed along a corresponding one of a plurality of paths at the input of the corresponding one of the plurality of amplifiers, and filters the signal received from the bandpass filter into each frequency band. Can be configured to

1 shows a wireless device having a communication module coupled to a primary antenna and a diversity antenna.
FIG. 2 shows a configuration of a diversity receiver (DRx) including a DRx front-end module (FEM).
3 shows that, in some embodiments, a diversity receiver (DRx) configuration may include a DRx module having a plurality of paths corresponding to a plurality of frequency bands.
4A shows that in some embodiments, a diversity receiver configuration may include a diversity receiver (DRx) module having a plurality of bandpass filters disposed at the outputs of a plurality of amplifiers.
4B shows that in some embodiments, a diversity receiver configuration may include a diversity RF module with fewer amplifiers than a diversity receiver (DRx) module.
5 shows that in some embodiments, a diversity receiver configuration may include a DRx module coupled to an off-module filter.
6 shows that in some embodiments, a diversity receiver configuration may include a DRx module with a tunable matching circuit.
7 shows a module with one or more features described herein.
8 illustrates a wireless device having one or more features described herein.

The preamble provided herein, if any, is for convenience only and does not necessarily affect the scope or meaning of the claimed invention.

1 shows a wireless device 100 having a communication module 110 coupled to a primary antenna 130 and a diversity antenna 140. The communication module 110 (and its constituent components) may be controlled by the controller 120. The communication module 110 includes a transceiver 112 configured to convert between an analog radio-frequency (RF) signal and a digital data signal. For that purpose, the transceiver 112 includes a digital-to-analog converter, an analog-to-digital converter, a local oscillator for modulating a baseband analog signal to a carrier frequency or demodulating a baseband analog signal from a carrier frequency, digital It may include a baseband processor, or other component that converts between samples and bits of data (eg, speech or other types of data).

The communication module 110 further includes an RF module 114 coupled between the main antenna 130 and the transceiver 112. Since the RF module 114 is physically close to the main antenna 130 to reduce attenuation due to cable loss, the RF module 114 may be referred to as a front-end module (FEM). . The RF module 114 may perform processing on an analog signal received from the transceiver 112 for transmission through the main antenna 130 or received from the main antenna 130 for the transceiver 112. For this purpose, the RF module 114 may include a filter, a power amplifier, a band select switch, a matching circuit, and other components. Similarly, the communication module 110 includes a diversity RF module 116 coupled between a diversity antenna 140 and a transceiver 112 that performs similar processing.

When a signal is transmitted to the wireless device, the signal can be received at both the main antenna 130 and the diversity antenna 140. The main antenna 130 and the diversity antenna 140 are physically separated from each other, so that signals from the main antenna 130 and the diversity antenna 140 are received with different characteristics. For example, in one embodiment, the main antenna 130 and the diversity antenna 140 may receive signals with different attenuation, noise, frequency response, or phase shift. The transceiver 112 can use both signals with different characteristics to determine the data bit corresponding to the signal. In some implementations, transceiver 112 selects between primary antenna 130 and diversity antenna 140 based on characteristics, such as selecting an antenna with the highest signal-to-noise ratio. In some implementations, transceiver 112 combines signals from primary antenna 130 and diversity antenna 140 to increase the signal-to-noise ratio of the combined signal. In some implementations, transceiver 112 processes signals to perform multiple-input/multi-output (MIMO) communication.

Since the diversity antenna 140 is physically separated from the main antenna 130, the diversity antenna 140 is provided with a communication module ( 110). In some implementations, the transmission line 135 is lossy and attenuates the signal received at the diversity antenna 140 before it reaches the communication module 110. Thus, in some implementations, a gain is applied to the signal received at the diversity antenna 140, as described below. The gain (and other analog processing, such as filtering) can be applied by the diversity receiver module. Since the diversity receiver module may be physically located close to the diversity antenna 140, it may be referred to as a diversity receiver front-end module. In contrast, the diversity RF module 116 coupled to the diversity antenna 140 through the transmission line 135 may be referred to as a backend module or a downstream module.

2 shows a diversity receiver (DRx) configuration 200 including a DRx front-end module (FEM) 210. The DRx configuration 200 includes a diversity antenna 140 configured to receive a diversity signal and provide the diversity signal to the DRx FEM 210. The DRx FEM 210 is configured to perform processing on the diversity signal received from the diversity antenna 140. For example, DRx FEM 210 may be configured to filter the diversity signal to one or more active frequency bands, as indicated by controller 120, for example. As another example, the DRx FEM 210 may be configured to amplify a diversity signal. For this purpose, the DRx FEM 210 may include filters, low-noise amplifiers, band select switches, matching circuits, and other components.

The DRx FEM 210 transmits the processed diversity signal to the diversity RF (D-RF) module 116 that provides an additional processed diversity signal to the transceiver 112 through the transmission line 135. do. The diversity RF module 116 (and, in some implementations, the transceiver 112) is controlled by the controller 120. In some implementations, the controller 120 may be implemented within the transceiver 112.

3 shows that in some embodiments, a diversity receiver (DRx) configuration 300 may include a DRx module 310 having a plurality of paths corresponding to a plurality of frequency bands. The DRx configuration 300 includes a diversity antenna 140 configured to receive a diversity signal. In some implementations, the diversity signal may be a single-band signal comprising data modulated into a single frequency band. In some implementations, the diversity signal may be a multi-band signal (also referred to as an inter-band carrier aggregation signal) containing data modulated into a plurality of frequency bands.

The DRx module 310 provides an input for receiving a diversity signal from the diversity antenna 140 and a processed diversity signal to the transceiver 330 (via the transmission line 135 and the diversity RF module 320). Has an output The input of the DRx module 310 is provided as an input of the first multiplexer (MUX) 311. The first multiplexer 311 includes a plurality of multiplexer outputs, and each of the outputs corresponds to a path between an input and an output of the DRx module 310. Each of the paths may correspond to a respective frequency band. The output of the DRx module 310 is provided by the output of the second multiplexer 312. The second multiplexer 312 includes a plurality of multiplexer inputs, and each of the inputs corresponds to one of paths between the input and the output of the DRx module 310.

The frequency bands may be cellular frequency bands, such as Universal Mobile Telecommunications System (UMTS) frequency bands. For example, the first frequency band may be a Universal Mobile Telecommunications System (UMTS) downlink or "Rx" band 2 between 1930 MHz and 1990 MHz, and the second frequency band is 869 MHz and 894 MHz. It may be between UMTS downlink or "Rx" band 5. Other downlink frequency bands may be used, such as those described in Table 1 below or other non-UMTS frequency bands.

In some implementations, the DRx module 310 includes a DRx controller 302 that receives a signal from the controller 120 (also referred to as a communication controller), and based on the received signal, a plurality of paths between the input and the output. Selectively activate one or more of them. In some implementations, the DRx module 310 does not include the DRx controller 302 and the controller 120 directly selectively activates one or more of the plurality of paths.

As mentioned above, in some implementations, the diversity signal is a single-band signal. Thus, in some implementations, the first multiplexer 311 is configured to route the diversity signal to one of a plurality of paths corresponding to the frequency band of the single-band signal based on the signal received from the DRx controller 302. -It is a single-pole/multiple-throw (SPMT) switch. The DRx controller 302 may generate a signal based on the band selection signal received by the DRx controller 302 from the communication controller 120. Similarly, in some implementations, the second multiplexer 312 receives a signal from the corresponding one of a plurality of paths corresponding to the frequency band of the single-band signal based on the signal received from the DRx controller 302. This is an SPMT switch that routes.

As mentioned above, in some implementations, the diversity signal is a multi-band signal. Thus, in some implementations, the first multiplexer 311 is configured to connect at least two of the plurality of paths corresponding to two or more frequency bands of the multi-band signal based on the splitter control signal received from the DRx controller 302. It is a band splitter that routes diversity signals. The function of the band splitter can be implemented as an SPMT switch, a diplexer filter, or some combination thereof. The diplexer is a triplexer, quadplexer, or an arbitrary configured to divide the input signal received at the input of the DRx module 310 into a plurality of signals in each of a plurality of frequency bands propagated along a plurality of paths It can be replaced with another multiplexer.

Similarly, in some implementations, the second multiplexer 312 may have two or more of a plurality of paths corresponding to two or more frequency bands of the multi-band signal based on the combiner control signal received from the DRx controller 302. It is a band combiner that combines the signals from The function of the band combiner can be implemented as an SPMT switch, a diplexer filter, or some combination thereof. The DRx controller 302 may generate a splitter control signal and a combiner control signal based on the band selection signal received by the DRx controller 302 from the communication controller 120.

Thus, in some implementations, the DRx controller 302 selectively activates one or more of the plurality of paths based on the band selection signal received by the DRx controller 302 (e.g., from the communication controller 120). Is configured to In some implementations, the DRx controller 302 is configured to selectively activate one or more of the plurality of paths by sending a splitter control signal to the band splitter and a combiner control signal to the band combiner.

The DRx module 310 includes a plurality of bandpass filters 313a-313d. Each of the bandpass filters 313a-313d is disposed along a corresponding one of a plurality of paths, and is configured to filter a signal received from the bandpass filter into a respective frequency band of the corresponding one of the plurality of paths. . In some implementations, the bandpass filters 313a-313d also filter the signal received at the bandpass filter into a downlink frequency sub-band of the respective frequency band of the corresponding one of the plurality of paths. Is configured to The DRx module 310 includes a plurality of amplifiers 314a-314d. Each of the amplifiers 314a-314d is disposed along a corresponding one of the plurality of paths and is configured to amplify a signal received at the amplifier.

In some implementations, the amplifiers 314a-314d are narrowband amplifiers configured to amplify a signal within a respective frequency band of the path in which the amplifier is disposed. In some implementations, the amplifiers 314a-314d are controllable by the DRx controller 302. For example, in some implementations, each of the amplifiers 314a-314d includes an enable/disable input and enables (or disables) based on the amplifier enable signal received at the received enable/disable input. )do. The amplifier enable signal may be transmitted by the DRx controller 302. Thus, in some implementations, the DRx controller 302 may enable one or more of the plurality of paths by transmitting an amplifier enable signal to one or more of the amplifiers 314a-314d respectively disposed along one or more of the plurality of paths. It is configured to selectively activate. In this implementation, rather than being controlled by the DRx controller 302, the first multiplexer 311 may be a band splitter that routes diversity signals to each of a plurality of paths, and the second multiplexer 312 is a plurality of paths. It may be a band combiner that combines the signals from each of them. However, in an implementation in which the DRx controller 302 controls the first multiplexer 311 and the second multiplexer 312, the DRx controller 302 may also use a specific amplifier 314a-314d to save battery, for example. ) Can be enabled (or disabled).

In some implementations, the amplifiers 314a-314d are variable-gain amplifiers (VGAs). Thus, in some implementations, the DRx module 310 includes a plurality of variable-gain amplifiers (VGAs), each of the VGAs being placed along a corresponding one of the plurality of paths and transmitting a signal received from the VGA to a DRx controller. It is configured to amplify with a gain controlled by the amplifier control signal received from 302.

The gain of VGA may be bypassable, step-variable, or continuously-variable. In some implementations, at least one of the VGAs includes a fixed-gain amplifier and a bypass switch controllable by the amplifier control signal. The bypass switch closes the line (in the first position) from the input of the fixed-gain amplifier to the output of the fixed-gain amplifier, allowing the signal to bypass the fixed-gain amplifier. The bypass switch opens the line between the input and output (in the second position), passing the signal through the fixed-gain amplifier. In some implementations, when the bypass switch is in the first position, the fixed-gain amplifier is disabled or otherwise reconfigured to accommodate the bypass mode.

In some implementations, at least one of the VGAs includes a step-variable gain amplifier configured to amplify a signal received at the VGA with a gain of one of a plurality of configured quantities indicated by the amplifier control signal. In some implementations, at least one of the VGAs includes a continuously-variable gain amplifier configured to amplify a signal received at the VGA with a gain proportional to the amplifier control signal.

In some implementations, the amplifiers 314a-314d are variable-current amplifiers (VCAs). The current drawn by the VCA can be bypassable, step-variable, or continuously-variable. In some implementations, at least one of the VCAs includes a fixed-current amplifier and a bypass switch controllable by the amplifier control signal. The bypass switch closes the line between the input of the fixed-current amplifier and the output of the fixed-current amplifier (in the first position), allowing the signal to bypass the fixed-current amplifier. The bypass switch opens the line between the input and output (in the second position), passing the signal through the fixed-current amplifier. In some implementations, when the bypass switch is in the first position, the fixed-current amplifier is disabled or otherwise reconfigured to accommodate the bypass mode.

In some implementations, at least one of the VCAs includes a step-variable current amplifier configured to amplify a signal received at the VCA by drawing a current of one of a plurality of configured quantities indicated by the amplifier control signal. In some implementations, at least one of the VCAs comprises a continuously-variable current amplifier configured to amplify a signal received at the VCA by drawing a current proportional to the amplifier control signal.

In some implementations, the amplifiers 314a-314d are fixed-gain, fixed-current amplifiers. In some implementations, amplifiers 314a-314d are fixed-gain, variable-current amplifiers. In some implementations, amplifiers 314a-314d are variable-gain, fixed-current amplifiers. In some implementations, amplifiers 314a-314d are variable-gain, variable-current amplifiers.

In some implementations, the DRx controller 302 generates the amplifier control signal(s) based on a quality of service metric of the input signal received at the input of the first multiplexer 311. In some implementations, the DRx controller 302 is based on the signal received from the communication controller 120, the amplifier control signal(s), which may in turn be based on a quality of service (QoS) metric of the received signal. Is created. The QoS metric of the received signal may be based, at least in part, on a diversity signal (eg, an input signal received at an input) received at the diversity antenna 140. The QoS metric of the received signal may be further based on the signal received at the primary antenna as well. In some implementations, the DRx controller 302 generates the amplifier control signal(s) based on the QoS metric of the diversity signal without receiving a signal from the communication controller 120.

In some implementations, the QoS metric includes signal strength. As another example, the QoS metrics may include bit error rate, data throughput, transmission delay, or any other QoS metric.

As mentioned above, the DRx module 310 transmits an input for receiving a diversity signal from the diversity antenna 140 and a processed diversity signal (through the transmission line 135 and the diversity RF module 320). It has an output provided to the transceiver 330. The diversity RF module 320 receives the processed diversity signal through the transmission line 135 and performs additional processing. In particular, the processed diversity signal is divided by a diversity RF multiplexer 321 (also referred to as a downstream multiplexer), or a bandpass filter 323a-323d to which the divided or routed signal corresponds (also referred to as Filtered by a downstream band pass filter) and amplified by corresponding amplifiers 324a-324d (also referred to as downstream amplifiers). The output of each of the amplifiers 324a-324d is provided to a transceiver 330.

Diversity RF multiplexer 321 may be controlled (directly or through an on-chip diversity RF controller) by controller 120 to selectively activate one or more of the paths. Similarly, the amplifiers 324a-324d can be controlled by the controller 120. For example, in some implementations, each of the amplifiers 324a-324d includes an enable/disable input and is enabled (or disabled) based on the amplifier enable signal. In some implementations, the amplifiers 324a-324d control the signal received at the VGA by an amplifier control signal received from the controller 120 (or the on-chip diversity RF controller controlled by the controller 120). It is a variable-gain amplifier (VGA) that amplifies with gain. In some implementations, the amplifiers 324a-324d are variable-current amplifiers (VCAs).

With the DRx module 310 added to the receiver chain that already includes the diversity RF module 320, the number of bandpass filters in the DRx configuration 300 is doubled. Thus, in some implementations as described below, the bandpass filters 323a-323d are not included in the diversity RF module 320. In some implementations, bandpass filters 323a-323d (eg, described below with respect to FIGS. 4A and 4B) are relocated to the DRx module 310. In some implementations, the bandpass filters 313a-313d of the DRx module 310 alone are used to reduce the strength of out-of-band blockers. In addition, the automatic gain control (AGC) table of the diversity RF module 320 indicates the amount of gain provided by the amplifiers 324a-324d of the diversity RF module 320, and the DRx module ( 310) can be shifted to reduce the amount of gain provided by the amplifiers 314a-314d.

For example, if the DRx module gain is 15 dB and the receiver sensitivity is -100 dBm, then the diversity RF module 320 will see a sensitivity of -85 dBm. If the closed loop AGC of the diversity RF module 320 is active, its gain will automatically drop by 15 dB. However, both signal components and out-of-band blockers are amplified and received by 15 dB. Thus, in some implementations, the 15 dB gain drop of the diversity RF module 320 is also accompanied by a 15 dB increase in its linearity. In particular, the amplifiers 324a to 324d of the diversity RF module 320 may be designed such that linearity of the amplifiers increases with a decrease in gain (or increase in current).

In some implementations, the controller 120 controls the gain (and/or current) of the amplifiers 314a-314d of the DRx module 310 and the amplifiers 324a-324d of the diversity RF module 320. As in the example above, the controller 120 responds to increasing the amount of gain provided by the amplifiers 314a-314d of the DRx module 310, and the amplifiers 324a-324d of the diversity RF module 320 You can reduce the amount of benefit provided by ). Thus, in some implementations, the controller 120 is based on the amplifier control signal (for the amplifiers 314a-314d of the DRx module 310) (amplifiers 324a-324d of the diversity RF module 320). For) a downstream amplifier control signal to control the gain of one or more downstream amplifiers 324a-324d coupled to the output (of the DRx module 310) via the transmission line 135. In some implementations, the controller 120 also controls the gain of other components of the wireless device, such as an amplifier in the main front-end module (FEM), based on the amplifier control signal.

As mentioned above, in some implementations, bandpass filters 323a-323d are not included. Thus, in some implementations, at least one of the downstream amplifiers 324a-324d is coupled to the output (of the DRx module 310) through the transmission line 135 without passing through a downstream bandpass filter.

4A shows, in some embodiments, a diversity receiver (DRx) with a diversity receiver configuration 400 having a plurality of bandpass filters 423a-423d disposed at the outputs of a plurality of amplifiers 314a-314d. It shows that the module 410 may be included. The diversity receiver configuration 400 includes a DRx module 410 having an input coupled to an antenna 140 and an output coupled to a transmission line 135. The DRx module 410 includes a number of paths between the input and the output of the DRx module 410. Each of the paths includes an input multiplexer 311, a pre-amplifier bandpass filter 413a-413d, an amplifier 314a-314d, a post-amplifier bandpass filter 423a-423d, and an output multiplexer 312. do.

DRx controller 302 is configured to selectively activate one or more of a plurality of paths between input and output. In some implementations, the DRx controller 302 is configured to selectively activate one or more of the plurality of paths based on the band selection signal received by the DRx controller 302 (e.g., from the communication controller 120). do. The DRx controller 302 may, for example, enable or disable the amplifiers 314a-314d, control the multiplexers 311 and 312, or selectively activate the path through other mechanisms.

The output of the DRx module 410 is a diversity RF module 420 different from the diversity RF module 320 of FIG. 3A in that the diversity RF module 420 of FIG. 4A does not include a downstream bandpass filter. ) Is transmitted through the transmission line 135. In some implementations (eg, as shown in FIG. 4A), the downstream multiplexer 321 may be implemented as a sample switch.

Including the post-amplifier bandpass filters 423a-423d within the DRx module 410 rather than the diversity RF module 420 may provide a number of advantages. For example, as described in detail below, this configuration may improve the noise figure of the DRx module 410, simplify filter design, and/or improve path isolation.

Each of the paths of the DRx module 410 may be characterized by a noise figure. The noise figure of each path is an expression of the degradation of the signal-to-noise ratio (SNR) caused by propagation along the path. In particular, the noise figure of each path is the decibel (dB) difference between the SNR at the input of the pre-amplifier bandpass filters 413a-413d and the SNR at the output of the post-amplifier bandpass filters 423a-4234b. Can be expressed. The noise figure of each path may be different for each frequency band. For example, the first path may have an in-band noise figure for a first frequency band and an out-of-band noise figure for a second frequency band. Similarly, the second path may have an in-band noise figure for the second frequency band and an out-of-band noise figure for the first frequency band.

The DRx module 410 may also be characterized by a noise figure that may differ from frequency band to frequency band. In particular, the noise figure of the DRx module 410 is the difference in decibels (dB) between the SNR at the input of the DRx module 410 and the SNR at the output of the DRx module 410.

Since signals propagating along the two paths are combined by the output multiplexer 312, out-of-band noise generated or amplified by the amplifier may negatively affect the combined signal. For example, out-of-band noise generated or amplified by the first amplifier 314a may increase the noise figure of the DRx module 410 at the second frequency. Accordingly, the post-amplifier bandpass filter 423a disposed along the path can reduce this out-of-band noise figure and reduce the noise figure of the DRx module 410 at the second frequency.

In some implementations, the pre-amplifier bandpass filters 413a-413d and post-amplifier bandpass filters 423a-423d are designed to be complementary, thereby simplifying filter design and/or reducing the number of reduced cost. Similar performance can be achieved with components. For example, the post-amplifier bandpass filter 423a disposed along the first path may more strongly attenuate frequencies that the pre-amplifier bandpass filter 413a disposed along the first path weakly attenuates. . For example, the pre-amplifier bandpass filter 413a may attenuate frequencies below the first frequency band more than frequencies above the first frequency band. Complementarily, the post-amplifier bandpass filter 423a may attenuate frequencies above the first frequency band more than frequencies below the first frequency band. Thus, together, the pre-amplifier bandpass filter 413a and the post-amplifier bandpass filter 423a attenuate all out-of-band frequencies using fewer components. In general, one of the bandpass filters placed along the path can attenuate frequencies below each frequency band of the path more than the frequencies above each frequency band, and among the bandpass filters placed along the path. Another can attenuate frequencies above each frequency band more than frequencies below each frequency band. The pre-amplifier bandpass filters 413a-413d and the post-amplifier bandpass filters 423a-423d may be mutually mutual in different ways. For example, the pre-amplifier bandpass filter 413a disposed along the first path may phase-shift the signal at a predetermined angle, and the post-amplifier bandpass filter 423a disposed along the first path Can be phase-shifted to the opposite side by a predetermined angle.

In some implementations, post-amplifier bandpass filters 423a-423d can improve isolation of paths. For example, if there is no post-amplifier bandpass filter, a signal propagating along the first path may be filtered to a first frequency by the pre-amplifier bandpass filter 413a and amplified by the amplifier 314a. The signal leaks through output multiplexer 312 and propagates backwards along the second path, and is reflected from amplifier 314b, pre-amplifier bandpass filter 413b, or other components disposed along the second path. If this reflected signal is out of phase with the initial signal, this may result in weakening of the signal when combined by the output multiplexer 312. In contrast, by the post-amplifier bandpass filter, the leaked signal (mainly in the first frequency band) is placed along the second path and attenuated by the post-amplifier bandpass filter 423b associated with the second frequency band. , Reduces the effect of any reflected signal.

Accordingly, the DRx module 410 is at least one of a plurality of paths between the input of the first multiplexer (eg, the input multiplexer 311) and the output of the second multiplexer (eg, the output multiplexer 312). And a controller configured to selectively activate. The DRx module 410 further includes a plurality of amplifiers 314a-314d, and each of the plurality of amplifiers 314a-314d is disposed along a corresponding one of the plurality of paths and transmits a signal received from the amplifier. It is configured to amplify. The DRx module 410 includes a first plurality of bandpass filters (eg, post-amplifier bandpass filters 423a-423d), and each of the first plurality of bandpass filters is a plurality of amplifiers. Arranged along a corresponding one of a plurality of paths at the output of the corresponding one of (314a-314d) and configured to filter a signal received in the bandpass filter into each frequency band. 4A, in some implementations, the DRx module 410 further includes a second plurality of bandpass filters (e.g., pre-amplifier bandpass filters 413a-413d), and a second plurality Each of the bandpass filters of is arranged along a corresponding one of a plurality of paths at the input of the corresponding one of the plurality of amplifiers 314a-314d, and filters the signal received from the bandpass filter into each frequency band. Is configured to

4B shows that in some embodiments, diversity receiver configuration 450 may include diversity RF module 460 with fewer amplifiers than diversity receiver (DRx) module 410. As mentioned above, in some implementations, the diversity RF module 460 may not include a bandpass filter. Thus, in some implementations, one or more amplifiers 424 of diversity RF module 460 need not be band-specific. In particular, the diversity RF module 460 may include one or more paths, and each path includes an amplifier 424 that is not mapped 1-to-1 with the paths of the DRx module 410. This mapping of paths (or the corresponding amplifier) may be stored in the controller 120.

Accordingly, the DRx module 410 includes a plurality of paths, and each path corresponds to a frequency band, whereas the diversity RF module 460 does not correspond to a single frequency band (diversity RF module 460). From the input to the input of the multiplexer 321).

In some implementations (shown in FIG. 4B), the diversity RF module 460 includes a single wideband or tunable amplifier 424 that amplifies the signal received from the transmission line 135 and multiplexes the amplified signal. 321). The multiplexer 321 includes a plurality of multiplexer outputs, each output corresponding to a respective frequency band. In some implementations, the multiplexer 321 may be implemented as a sample switch. In some implementations, diversity RF module 460 does not include any amplifiers.

In some implementations, the diversity signal is a single-band signal. Thus, in some implementations, the multiplexer 321 routes the diversity signal to one of a plurality of outputs corresponding to the frequency band of the single-band signal based on the signal received from the controller 120. pole / multiple-throw) switch. In some implementations, the diversity signal is a multi-band signal. Thus, in some implementations, the multiplexer 421 provides a diversity signal to at least two of the plurality of outputs corresponding to at least two frequency bands of the multi-band signal based on the splitter control signal received from the controller 120. It is a band splitter for routing. In some implementations, diversity RF module 460 may be combined with transceiver 330 as a single module.

In some implementations, diversity RF module 460 includes a plurality of amplifiers, each amplifier corresponding to a set of frequency bands. The signal from the transmission line 135 may be transferred into a band splitter that outputs a high frequency to a high frequency amplifier along a first path and a low frequency to a low frequency amplifier along a second path. The output of each of the amplifiers may be provided to a multiplexer 321 configured to route signals to a corresponding input of the transceiver 330.

5 shows that in some embodiments, diversity receiver configuration 500 may include a DRx module 510 coupled to one or more off-module filters 513, 523. The DRx module 510 may include a packaging substrate 501 configured to accommodate a plurality of components and a receiving system implemented on the packaging substrate 501. The DRx module 510 may include one or more signal paths routed from the DRx module 510 and made available to a system integrator, designer, or manufacturer to support filters for any desired band.

The DRx module 510 includes a number of paths between the input and the output of the DRx module 510. The DRx module 510 includes a bypass path between the input and output that is activated by the bypass switch 519 controlled by the DRx controller 502. 5 shows a single bypass switch 519, but in some implementations, the bypass switch 519 has a plurality of switches (e.g., a first switch placed in physical proximity to the input and physical proximity to the output). It may include a disposed second switch). As shown in Fig. 5, the bypass path does not include a filter or amplifier.

The DRx module 510 includes a plurality of multiplexer paths including a first multiplexer 511 and a second multiplexer 512. The multiplexer path includes a first multiplexer 511, pre-amplifier bandpass filters 413a-413d implemented on the packaging substrate 501, amplifiers 314a-314d implemented on the packaging substrate 501, and a packaging substrate. A plurality of on-module paths including post-amplifier bandpass filters 423a-423d implemented on 501, and a second multiplexer 512 are included. The multiplexer path is a pre-amplifier bandpass filter 513 implemented separately from the first multiplexer 511 and the packaging substrate 501, an amplifier 514, and a post implemented separate from the packaging substrate 501. The amplifier bandpass filter 523, and the second multiplexer 512 include one or more off-module paths. The amplifier 514 may be a broadband amplifier implemented on the packaging substrate 501 or may be implemented separately from the packaging substrate 501. In some implementations, the one or more off-module paths do not include a pre-amplifier bandpass filter 513, but a post-amplifier bandpass filter 523. As described above, the amplifiers 314a-314d and 514 may be a variable-gain amplifier and/or a variable-current amplifier.

DRx controller 502 is configured to selectively activate one or more of a plurality of paths between input and output. In some implementations, the DRx controller 502 is configured to selectively activate one or more of the plurality of paths based on a band select signal received by the DRx controller 502 (eg, from a communication controller). The DRx controller 502, for example, opens or closes the bypass switch 519, enables or disables the amplifiers 314a-314d, 514, controls the multiplexers 511, 512, or other The pathway can be selectively activated through the mechanism of. For example, the DRx controller 502 may be along a path (e.g., between filters 313a-313d, 513 and amplifiers 314a-314d, 514) or amplifiers 314a-314d, 514 The switches can be opened or closed by setting the gain of substantially zero.

6 shows that in some embodiments, diversity receiver configuration 600 may include a DRx module 610 with a tunable matching circuit. In particular, the DRx module 610 may include one or more tunable matching circuits disposed at one or more of an input and an output of the DRx module 610.

It is unlikely that all of the plurality of frequency bands received on the same diversity antenna 140 will see ideal impedance matching. In order to match each frequency band using a compact matching circuit, a tunable input matching circuit 616 can be implemented at the input of the DRx module 610 (e.g., in the band selection signal from the communication controller). Based) can be controlled by the DRx controller 602. The DRx controller 602 may tune the tunable input matching circuit 616 based on a lookup table that associates a frequency band (or set of frequency bands) with a tuning parameter. The tunable input matching circuit 616 may be a tunable T-circuit, a tunable PI-circuit, or any other tunable matching circuit. In particular, the tunable input matching circuit 616 may include one or more variable components, such as resistors, inductors, and capacitors. The variable components may be connected in parallel and/or in series and may be connected between the input of the DRx module 610 and the input of the first multiplexer 311 or between the input of the DRx module 610 and the ground voltage.

Similarly, with only one transmission line 135 (or at least a few cables) carrying signals of many frequency bands, it is unlikely that all of the plurality of frequency bands will see an ideal impedance match. In order to match each frequency band using a compact matching circuit, a tunable output matching circuit 617 can be implemented at the output of the DRx module 610 (e.g., in the band selection signal from the communication controller). Based) can be controlled by the DRx controller 602. The DRx controller 602 can tune the tunable output matching circuit 618 based on a lookup table that associates a frequency band (or set of frequency bands) with a tuning parameter. The tunable output matching circuit 617 may be a tunable T-circuit, a tunable PI-circuit, or any other tunable matching circuit. In particular, the tunable output matching circuit 617 may include one or more variable components, such as resistors, inductors, and capacitors. The variable components may be connected in parallel and/or series and may be connected between the output of the DRx module 610 and the output of the second multiplexer 312 or between the output of the DRx module 610 and the ground voltage.

Figure 7 shows that, in some embodiments, some or all of the diversity receiver configurations (e.g., those shown in Figures 3, 4A, 4B, 5, and 6) may, in whole or in part, be implemented as a module. Shows that you can. Such a module may be, for example, a front-end module (FEM). Such a module may be, for example, a diversity receiver (DRx) FEM. In the example of FIG. 7, module 700 may include a packaging substrate 702, and multiple components may be mounted on such packaging substrate 702. For example, a controller 704 (which may include a front-end power management integrated circuit [FE-PIMC]), a low noise amplifier assembly 706 (which may include one or more variable-gain amplifiers), (one A matching component 708, which may include one or more tunable matching circuits, a multiplexer assembly 710, and one or more pre-amplifier bandpass filters 713 and/or one or more post-amplifier bandpass filters 723. A filter bank 712 may be mounted and/or implemented on and/or within the packaging substrate 702. Other components, such as multiple SMT devices 714 may also be mounted on the packaging substrate 702. While all of the various components are shown as being laid out on the packaging substrate 702, it will be appreciated that some component(s) may be implemented on top of other component(s).

In some implementations, devices and/or circuits having one or more features described herein may be included in an RF electronic device, such as a wireless device. Such devices and/or circuits may be implemented directly in the wireless device, in a modular form as described herein, or some combination thereof. In some embodiments, such wireless devices may include, for example, cellular telephones, smartphones, handheld wireless devices with or without telephony capabilities, wireless tablets, and the like.

8 shows an example wireless device 800 having one or more of the beneficial features described herein. In the context of one or more modules having one or more features described herein, these modules are generally dashed box 801 (which may be implemented as, for example, a front-end module), (e.g., a downstream module). A diversity RF module 811 (which may be implemented as), and a diversity receiver (DRx) module 700 (which may be implemented as, for example, a front-end module).

8, a power amplifier (PA) 820 receives and receives their respective RF signals from a transceiver 810, which can be configured and operated in a known manner to generate an RF signal to be amplified and transmitted. Processed signals. The transceiver 810 is shown interacting with a baseband subsystem 808 configured to provide conversion between data and/or voice signals suitable for a user and an RF signal suitable for the transceiver 810. The transceiver 810 may also communicate with a power management component 806 configured to manage power for operation of the wireless device 800. This power management can also control the operation of the baseband subsystem 808 and modules 801, 811, and 900.

The baseband subsystem 808 is shown connected to the user interface 802 to facilitate various input and output of voice and/or data provided to or received from the user. The baseband subsystem 808 may also be connected to a memory 804 configured to store data and/or instructions and/or provide storage of information to a user to facilitate operation of the wireless device.

In the example wireless device 800, the outputs of the PAs 820 are shown to be matched (via respective matching circuit 822) and routed to their respective duplexer 824. These amplified and filtered signals can be routed to the main antenna 816 through the antenna switch 814 for transmission. In some embodiments, duplexer 824 may allow transmit and receive operations to be performed simultaneously using a common antenna (eg, primary antenna 816). In FIG. 8, the received signal is shown to be routed to the “Rx” path, which may include, for example, a low-noise amplifier (LNA).

The wireless device also includes a diversity antenna 826 and a diversity receiver module 700 that receives signals from the diversity antenna 826. The diversity receiver module 700 processes the received signal and transmits the processed signal to the diversity RF module 811 which further processes the signal before feeding it to the transceiver 810 through a transmission line 835. send.

One or more features of the present disclosure may be implemented in the various cellular frequency bands described herein. Examples of these bands are listed in Table 1. It will be appreciated that at least some of the bands may be divided into sub-bands. It will also be appreciated that one or more features of the present disclosure may be implemented in a frequency range that does not have a designation such as the example in Table 1.

Throughout the detailed description and claims, unless the context clearly requires otherwise, the words "comprising", "comprising", etc. should be interpreted in an inclusive, not exclusive or exhaustive sense. do; That is, it means "including, but not limited to". The word “coupled”, as generally used herein, refers to two or more elements that are directly connected or that may be connected through one or more intermediate elements. In addition, the words "herein", "described above", "described below", and words of similar meaning, as used in this application, refer to this application as a whole and not any particular part of this application. If the context allows, words in the above description using the singular or plural may also include the plural or singular, respectively. The word "or" in reference to a list of two or more items encompasses all of the following interpretations: any of the items in the list, all of the items in the list, and any combination of the items in the list.

The above detailed description of embodiments of the invention is not intended to be exhaustive or to limit the invention to the exact form disclosed above. Although specific embodiments and examples of the present invention have been described above for purposes of illustration, various equivalent modifications are possible within the scope of the present invention, as those skilled in the art will recognize. For example, processes or blocks are presented in a given order, but alternative embodiments may use systems with blocks or perform routines with steps in a different order, and some processes or blocks may be deleted, moved, It can be added, subdivided, combined and/or modified. Each of these processes or blocks can be implemented in a variety of different ways. Also, although processes or blocks are sometimes shown to be performed in succession, these processes or blocks may instead be performed in parallel, or may be performed at different times.

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

While 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 the present disclosure. Indeed, the novel methods and systems described herein may be implemented in a variety of different forms; Further, various omissions, substitutions, and changes may be made in the form of the methods and systems described herein without departing from the spirit of the present disclosure. The appended claims and their equivalents are intended to cover such forms or modifications that fall within the scope and spirit of this disclosure.

Claims (19)

As a receiving system,
A controller configured to selectively activate at least one of the plurality of paths between the input of the first multiplexer and the output of the second multiplexer;
A plurality of amplifiers, each of the plurality of amplifiers being disposed along a corresponding one of the plurality of paths and configured to amplify a signal received from the amplifier;
A plurality of pre-amplifier bandpass filters-Each of the pre-amplifier bandpass filters is arranged along a corresponding one of the plurality of paths at the input of a corresponding amplifier among the plurality of amplifiers, and each pre-amplifier bandpass filter Are configured to filter the signal received by the pre-amplifier bandpass filter into each frequency band causing out-of-band noise amplified by the corresponding amplifier; And
A plurality of post-amplifier bandpass filters-Each of the post-amplifier bandpass filters is arranged along a corresponding one of the plurality of paths at the output of a corresponding amplifier among the plurality of amplifiers, while in the post-amplifier bandpass filter. The plurality of pre-amplifier bandpass arranged along a first path among the plurality of paths, configured to filter the received signal into each frequency band and reduce the out-of-band noise amplified by the corresponding amplifier Among the filters, each of the pre-amplifier bandpass filters phase-shifts the signal with a first phase shift, and each of the plurality of post-amplifier bandpass filters disposed along the first path is the post-amplifier bandpass filter. Phase-shifting the signal with a second phase shift opposite the first phase shift-
Containing, receiving system. The method of claim 1, wherein one of the post-amplifier band-pass filters disposed along the first path or one of the pre-amplifier band-pass filters moves frequencies below the first frequency band above the first frequency band. And the other one of the post-amplifier band-pass filters disposed along the first path or the other one of the pre-amplifier band-pass filters to reduce the frequencies above the first frequency band. A receiving system that attenuates more than frequencies below the first frequency band. The receiving system of claim 1, further comprising a transmission line coupled to an output of the second multiplexer and coupled to a downstream module comprising a downstream multiplexer. 4. The system of claim 3, wherein the downstream module does not include a downstream bandpass filter. 5. The receiving system of claim 4, wherein the downstream multiplexer comprises a sample switch. 6. The system of claim 5, wherein the number of one or more downstream amplifiers is less than the number of the plurality of amplifiers. 4. The system of claim 3, wherein the downstream module comprises one or more downstream amplifiers. The receiving system of claim 1, wherein at least one of the plurality of amplifiers comprises a low-noise amplifier. The receiving system of claim 1, further comprising one or more tunable matching circuits disposed on at least one of an input of the first multiplexer and an output of the second multiplexer. The receiving system of claim 1, wherein the controller is configured to selectively activate one or more of the plurality of paths based on a band selection signal received by the controller. The receiving system of claim 1, wherein the controller is configured to selectively activate one or more of the plurality of paths by transmitting a splitter control signal to the first multiplexer and a combiner control signal to the second multiplexer. The method of claim 1, wherein each of the pre-amplifier bandpass filters disposed along the first path attenuates frequencies below the first frequency band more than frequencies above the first frequency band and follows the first path. Wherein each post-amplifier bandpass filter disposed attenuates frequencies above the first frequency band more than frequencies below the first frequency band. As a radio frequency module,
A packaging substrate configured to receive a plurality of components; And
Receiving system implemented on the packaging substrate
Including,
The receiving system comprises: a controller configured to selectively activate at least one of a plurality of paths between an input of a first multiplexer and an output of a second multiplexer; A plurality of amplifiers, each of the plurality of amplifiers being disposed along a corresponding one of the plurality of paths and configured to amplify a signal received from the amplifier; First plurality of bandpass filters-Each of the first plurality of bandpass filters is disposed along a corresponding one of the plurality of paths at an output of a corresponding amplifier among the plurality of amplifiers, and received from the bandpass filter. -Configured to filter the signal into each frequency band; And a second plurality of bandpass filters, wherein each of the second plurality of bandpass filters is disposed along a corresponding path among the plurality of paths at an input of a corresponding amplifier among the plurality of amplifiers, by the corresponding amplifier. Amplified and configured to filter the signal received by the bandpass filter into each frequency band causing out-of-band noise that is amplified and reduced by a corresponding bandpass filter among the first plurality of bandpass filters, and the plurality of The first bandpass filter of the first plurality of bandpass filters disposed along the first path among the paths of is phase-shifted the signal by a first phase shift and the second plurality of bands disposed along the first path A second bandpass filter of the pass filter phase-shifts the signal with a second phase shift opposite to the first phase shift. 14. The radio frequency module of claim 13, wherein the radio frequency module is a diversity receiver front-end module. 14. The radio frequency module of claim 13, wherein the plurality of paths comprises an off-module bandpass filter and an off-module path comprising one of the plurality of amplifiers. The method of claim 13, wherein one of the bandpass filters disposed along the first path attenuates frequencies below the first frequency band more than frequencies above the first frequency band, and further attenuates frequencies below the first frequency band. The other one of the arranged bandpass filters attenuates frequencies above the first frequency band more than frequencies below the first frequency band. As a wireless device,
A first antenna configured to receive a first radio-frequency signal;
A first front-end module in communication with the first antenna-The first front-end module includes a packaging substrate configured to accommodate a plurality of components, and the first front-end module is implemented on the packaging substrate. A receiving system further comprising a receiving system, the receiving system comprising: a controller configured to selectively activate at least one of a plurality of paths between an input of the first multiplexer and an output of the second multiplexer; A plurality of amplifiers, each of the plurality of amplifiers being disposed along a corresponding one of the plurality of paths and configured to amplify a signal received from the amplifier; First plurality of bandpass filters-Each of the first plurality of bandpass filters is disposed along a corresponding one of the plurality of paths at the amplifier output of a corresponding amplifier among the plurality of amplifiers, and is received by the bandpass filter -Configured to filter the resulting signal into each frequency band; And a second plurality of bandpass filters, wherein each of the second plurality of bandpass filters is disposed along a corresponding path among the plurality of paths at an input of a corresponding amplifier among the plurality of amplifiers, by the corresponding amplifier. Amplified and configured to filter the signal received by the bandpass filter into each frequency band causing out-of-band noise that is amplified and reduced by a corresponding bandpass filter among the first plurality of bandpass filters, and the plurality of The first bandpass filter of the first plurality of bandpass filters disposed along the first path among the paths of is phase-shifted the signal by a first phase shift and the second plurality of bands disposed along the first path A second bandpass filter among the pass filters phase-shifts the signal with a second phase shift opposite to the first phase shift; And
A communication module configured to receive a processed version of the first radio-frequency signal from the output of the second multiplexer over a transmission line and generate data bits based on the processed version of the first radio-frequency signal
Wireless device comprising a. The method of claim 17, further comprising a second antenna configured to receive a second radio-frequency signal and a second front-end module in communication with the second antenna, wherein the communication module comprises: the second front-end module And configured to receive a processed version of the second radio-frequency signal from an output of and generate data bits based on the processed version of the second radio-frequency signal. The method of claim 17, wherein one of the bandpass filters disposed along the first path attenuates frequencies below the first frequency band more than frequencies above the first frequency band, and further attenuates frequencies below the first frequency band. Wherein the other of the disposed bandpass filters attenuates frequencies above the first frequency band more than frequencies below the first frequency band.

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