CN114285423B

CN114285423B - Radio frequency L-PA Mid device, radio frequency receiving and transmitting system and communication equipment

Info

Publication number: CN114285423B
Application number: CN202011034167.1A
Authority: CN
Inventors: 冯斌
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2020-09-27
Filing date: 2020-09-27
Publication date: 2023-12-15
Anticipated expiration: 2040-09-27
Also published as: CN114285423A

Abstract

The application provides a radio frequency L-PA Mid device, a radio frequency receiving and transmitting system and communication equipment, wherein the radio frequency L-PA Mid device is configured with at least one transmitting port, a plurality of receiving ports and at least one antenna port, and the radio frequency L-PA Mid device comprises: the transmitting module is used for receiving a plurality of low-frequency signals and amplifying and filtering the received low-frequency signals; the first switch unit is respectively connected with the transmitting module correspondingly at a plurality of first ends, and the second end of the first switch unit is connected with an antenna port; the receiving module is respectively connected with a plurality of first ends and each receiving port of the first switch unit, and comprises at least one low-noise amplifier, filters the processed low-frequency signals and outputs at least one low-frequency signal after being amplified by each low-noise amplifier; the first control unit is used for adjusting the gain coefficient of the low-noise amplifier so as to reduce the cascade noise coefficient of at least one low-frequency signal receiving path, and further improve the sensitivity of the radio frequency receiving and transmitting system.

Description

Radio frequency L-PA Mid device, radio frequency receiving and transmitting system and communication equipment

Technical Field

The present application relates to the field of radio frequency technologies, and in particular, to a radio frequency L-PA Mid device, a radio frequency transceiver system, and a communication device.

Background

With the development and progress of technology, in order to cope with the increasing demands of various network systems and to solve the problem of PCB layout shortage, the high integration and miniaturization of devices are apparently a trend. From a Phase2 product which only supports single frequency band at first to a Phase7 product which supports integration of various systems, the integration level of the device is higher and higher, and meanwhile, the packaging size of the device is also smaller and smaller. A low frequency power amplifier module with built-in low noise amplifier is generally defined in a 2G, 3G or 4G architecture design, but when the module is applied to a radio frequency transceiver system to receive a low frequency signal, the sensitivity of a receiving path in the radio frequency transceiver system is low.

Disclosure of Invention

The embodiment of the application provides a radio frequency L-PA Mid device, a radio frequency receiving and transmitting system and communication equipment, which can improve the sensitivity of the radio frequency L-PA Mid device.

A radio frequency L-PA Mid device configured with at least one transmit port and a plurality of receive ports for connecting a radio frequency transceiver and at least one antenna port for connecting an antenna, the radio frequency L-PA Mid device comprising:

the transmitting module is connected with the transmitting port and is used for receiving a plurality of low-frequency signals and amplifying and filtering the received low-frequency signals;

The first switch unit is connected with the transmitting module correspondingly, and the second end of the first switch unit is connected with one antenna port;

the receiving module is respectively connected with each first end of the first switch unit and each receiving port, and is used for receiving a plurality of low-frequency signals and amplifying and filtering the received low-frequency signals, wherein the receiving module comprises at least one low-noise amplifier, and the low-frequency signals after filtering are amplified by each low-noise amplifier and then output at least one low-frequency signal;

the first control unit is connected with at least one low-noise amplifier and used for adjusting the gain coefficient of the low-noise amplifier so as to reduce the cascade noise coefficient of at least one low-frequency signal receiving path.

A radio frequency transceiver system comprising:

as with the rf L-PA Mid device described above,

the first antenna is connected with the antenna port and is used for receiving and transmitting the low-frequency signals;

the radio frequency transceiver is respectively connected with the transmitting port and the receiving port of the radio frequency L-PA Mid device and is used for transmitting the low-frequency signal to the radio frequency L-PA Mid device and receiving the low-frequency signal amplified by the radio frequency L-PA Mid device so as to realize the receiving and transmitting control of the low-frequency signal.

A communication device comprises the radio frequency transceiver system.

The radio frequency L-PA Mid device, the radio frequency receiving and transmitting system and the communication equipment integrate the receiving module, the transmitting module and the first switch unit, so that the receiving and transmitting control of a plurality of low-frequency signals can be realized, the external corresponding switching circuit on the traditional radio frequency L-PA Mid device can be avoided to realize the receiving of the low-frequency signals, the integration level of the radio frequency L-PA Mid device is improved, meanwhile, the external switching circuit is omitted, the link loss on a receiving path can be reduced, and the gain coefficient of a low-noise amplifier in the receiving module is regulated, so that the cascade noise coefficient of at least one low-frequency signal receiving path is reduced, and the sensitivity of the radio frequency L-PA Mid device can be improved.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is one of the block diagrams of the structure of a radio frequency L-PA Mid device in one embodiment;

FIG. 2a is a second block diagram of the RF L-PA Mid device in one embodiment;

FIG. 2b is a third block diagram of the RF L-PA Mid device in one embodiment;

FIG. 3 is a fourth block diagram of the structure of a radio frequency L-PA Mid device in one embodiment;

FIG. 4 is a fifth block diagram of the structure of a radio frequency L-PA Mid device in one embodiment;

FIG. 5 is a block diagram of a radio frequency L-PA Mid device in one embodiment;

FIG. 6 is a block diagram of a radio frequency L-PA Mid device in one embodiment;

FIG. 7 is a block diagram of a radio frequency L-PA Mid device in one embodiment;

FIG. 8 is a block diagram of a radio frequency L-PA Mid device in one embodiment;

fig. 9 is a block diagram of a rf L-PA Mid device in one embodiment;

FIG. 10a is a schematic diagram of a pin of the RF L-PA Mid device of FIG. 8;

FIG. 10b is a schematic diagram of a package structure of the RF L-PA Mid device of FIG. 8;

FIG. 11a is a schematic diagram of a pin of the RF L-PA Mid device of FIG. 9;

FIG. 11b is a schematic diagram of a package structure of the RF L-PA Mid device of FIG. 9;

FIG. 12 is one of the block diagrams of the RF transceiver system in one embodiment;

FIG. 13 is a second block diagram of an RF transceiver system in one embodiment;

FIG. 14 is a third block diagram of a power RF transceiver system in one embodiment;

fig. 15 is a block diagram of a power rf transceiver system in one embodiment.

Detailed Description

In order that the above objects, features and advantages of the application will be readily understood, a more particular description of the application will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, and the preferred embodiments of the present application are presented in the accompanying drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete. The present application may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the application, so that the application is not limited to the specific embodiments disclosed below.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present application, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise. In the description of the present application, the meaning of "several" means at least one, such as one, two, etc., unless specifically defined otherwise.

The radio frequency L-PA Mid device according to the embodiment of the present application may be applied to a communication device having a wireless communication function, where the communication device may be a handheld device, a vehicle-mounted device, a wearable device, a computing device, or other processing devices connected to a wireless modem, and various types of User Equipment (UE) (e.g., a Mobile Station, MS), and so on. For convenience of description, the above-mentioned devices are collectively referred to as communication devices. The network devices may include base stations, access points, and the like.

As shown in fig. 1, an embodiment of the present application provides a radio frequency L-PA Mid device. The radio frequency L-PA Mid device can be understood as a power amplifier module (Power Amplifier Modules including Duplexers With LNA, L-PA Mid) with a built-in low noise amplifier. The radio frequency L-PA Mid device can support the receiving and transmitting of low-frequency signals of a plurality of frequency bands, and realize the receiving switching control, the transmitting switching control and the switching control between the transmitting and the receiving of the plurality of low-frequency signals. The plurality of low frequency signals may include low frequency signals of different frequency bands among the 2G signal, the 3G signal, and the 4G signal. Specifically, the frequency bands of the plurality of low frequency signals may include at least two of B8, B12, B20, B26, B28A, B28B, B, B19 or any combination thereof, including at least one overseas frequency band of B28A, B28B, B13, B29. Therefore, the radio frequency L-PA Mid device in the embodiment of the present application may also be referred to as a low frequency power amplifier module (Low Band PA Mid With LNA, LB L-PA Mid) with a built-in low noise amplifier.

In one embodiment, the rf L-PA Mid device may be understood as a package structure, which is configured with at least one transmit port 4G LB RFIN and a plurality of receive ports LNA OUT for connection to an rf transceiver and at least one antenna port ANT for connection to an antenna. The receiving port LNA OUT, the transmitting port 4G LB RFIN and the antenna port ANT configured in the device can be understood as the radio frequency pin terminals of the radio frequency L-PA Mid device for connection with various external devices. In particular, the receive port LNA OUT, the transmit port 4G LB RFIN may be used to connect with a radio frequency transceiver. The antenna port ANT may be used for connection with an antenna. The transmitting port 4G LB RFIN is for receiving a plurality of low frequency signals sent by the radio frequency transceiver, and the radio frequency L-PA Mid device may perform filtering and amplifying processing on the input plurality of low frequency signals to output the signals to the antenna interface, and transmit the signals through an antenna connected to the antenna port ANT, so as to implement transmission control of the plurality of low frequency signals. The antenna port ANT is configured to receive a plurality of low-frequency signals received by the antenna, and the radio-frequency L-PA Mid device may perform processing filtering amplification processing on the plurality of input low-frequency signals, so as to output the signals to the receiving port LNA OUT, and output the signals to the radio-frequency transceiver through the receiving port LNA OUT, so as to implement receiving control on the plurality of low-frequency signals.

Specifically, the radio frequency L-PA Mid device comprises: the first switching unit 130 and the first control unit 140 are connected to the transmitting module 110 and the receiving module 120.

The transmitting module 110 includes an input and a plurality of outputs. The input end of the transmitting module 110 is connected to the transmitting port 4G LB RFIN, and the plurality of output ends of the transmitting module 110 are connected to the plurality of first ends of the first switch unit 130 in a one-to-one correspondence manner. Among them, the transmission port 4G LB RFIN, the transmission module 110, the first switching unit 130, and the antenna port ANT may constitute a plurality of transmission paths. That is, the transmitting module 110 receives a plurality of low frequency signals through the transmitting port 4G LB RFIN, amplifies and filters the received low frequency signals, and selects any one low frequency signal from the plurality of low frequency signals after the filtering and amplifying processes through the first switch unit 130 to output to the antenna port ANT, so as to realize the switching and transmitting control of the plurality of low frequency signals.

The receiving module 120 includes a plurality of input terminals and at least one output terminal. The multiple input ends of the receiving module 120 are connected to the multiple first ends of the first switch unit 130 in a one-to-one correspondence manner, and are used for receiving multiple low-frequency signals, amplifying and filtering the received multiple low-frequency signals, and at least one output end of the receiving module 120 is connected to at least one receiving port LNA OUT correspondingly. The antenna port ANT, the first switching unit 130, the receiving module 120, and the receiving port LNA OUT may constitute a plurality of receiving paths. The receiving module 120 includes at least one low noise amplifier 121, and an output terminal of each low noise amplifier 121 can be used as an output terminal of the receiving module 120. The filtered low-frequency signals are amplified by the low-noise amplifiers 121 and output at least one low-frequency signal to the corresponding receiving port LNA OUT, so as to realize switching receiving control of the low-frequency signals.

The first ends of the first switch unit 130 can be connected to the input ends of the receiving module 120 and the output ends of the transmitting module 110 in a one-to-one correspondence manner. The second end of the first switching unit 130 is connected to an antenna port ANT, and the first switching unit 130 can selectively turn on either a transmission path or a reception path of a low frequency signal. For example, when the rf L-PA Mid device is in the transmitting mode, the first switch unit 130 may be controlled to selectively conduct the path between the transmitting module 110 and the antenna port ANT to conduct any low-frequency signal transmitting path, and when the rf L-PA Mid device is in the receiving mode, the first switch unit 130 may be controlled to selectively conduct the path between the receiving module 120 and the antenna port ANT to conduct any low-frequency signal receiving path.

It should be noted that, in the embodiment of the present application, in the rf L-PA Mid device, a corresponding receiving path and transmitting path are respectively configured for each low frequency signal.

In one embodiment, a first end of the first switching unit 130 is correspondingly connected to an input of the receiving module 120 and/or an output of the transmitting module 110. Specifically, the input end of the receiving module 120 and the output end of the transmitting module 110 are arranged in pairs. Further, the input/output terminals arranged in pairs share the same transceiving terminal.

The first control unit 140 is connected to the at least one low noise amplifier 121, and is configured to adjust a gain factor of the low noise amplifier 121 to reduce a cascading noise factor of the at least one low frequency signal receiving path.

In one embodiment, the first control unit 140 may be a mobile industry processor interface (Mobile Industry Processor Interface, MIPI) -radio frequency front end control interface (RF Front End Control Interface, RFFE) control unit. When the first control unit 140 is a MIPI-RFFE control unit, its radio frequency L-PA Mid device is also configured with an input pin CLK for a clock signal, an input or bi-directional pin sdathas for a single/bi-directional data signal, a power supply pin VDD, a reference voltage pin VIO, and so on.

The receiving path of the radio frequency L-PA Mid device is formed by a plurality of cascaded devices such as an antenna port ANT, a first switch unit 130, a low noise amplifier 121 of a receiving module 120, a receiving port LNA OUT, and the like, and the calculation formula of the cascaded noise figure is shown in formula 1:

nf=n1+ (N2-1)/g1+ (N3-1)/g1×g2+ (N4-1)/g1×g2×g3+ … (formula 1)

Wherein N1 to N4 represent noise coefficients of the first stage to the fourth stage, and G1 to G3 represent gains of the first stage to the third stage, respectively, and a final cascade noise coefficient of the entire receiving path can be calculated by the formula (1). The noise figure of the low noise amplifier 121 can be changed by adjusting the gain coefficient of the low noise amplifier 121 in the reception path, and thus the cascade noise figure can be changed.

Sensitivity is the minimum input signal level that a communication device can receive when meeting certain Bit Error Rate (BER) performance. The communication protocol 3GPP provides that when the sensitivity index is tested, the required bit error rate must be lower than 5%, namely the Throughput is higher than 95%; under the above conditions, the measured minimum input level signal is the sensitivity of the communication device. The sensitivity can be calculated by a theoretical formula, specifically as shown in formula (2):

sensor= -174+10lgbw+nf (formula 2)

BW refers to the bandwidth of the working frequency band of the communication equipment, and the unit is Hz; NF refers to the cascading noise figure of the communication device in dB. The sensitivity of the communication device can be correspondingly improved by reducing the cascading noise figure.

The above-mentioned rf L-PA Mid device integrates the receiving module 120, the transmitting module 110, and the first switching unit 130, so as to implement transmit-receive control of multiple low-frequency signals, avoid externally arranging a corresponding switching circuit on a conventional rf L-PA Mid device to implement receiving of low-frequency signals, improve the integration level of the rf L-PA Mid device, and simultaneously, reduce link loss on a receiving path by omitting the externally arranged switching circuit and reduce cascade noise coefficient of at least one low-frequency signal receiving path by adjusting gain coefficient of the low-noise amplifier 121 in the receiving module 120, thereby improving sensitivity of the rf L-PA Mid device.

As shown in fig. 2a, in one embodiment, the receiving module 120 further includes a plurality of receiving circuits 122 and a second switching unit 123. One receiving circuit 122 is correspondingly connected to one first end of the first switch unit 130, and the frequency band of the low-frequency signal output by each receiving circuit 122 is different. Specifically, each receiving circuit 122 may include a filter. The filter can perform filtering processing on the received low-frequency signal, wherein the filter only allows the low-frequency signal of a preset frequency band to pass. For example, if the frequency bands of the plurality of low frequency signals may be eight different frequency bands of B8, B12, B20, B26, B28A, B28B, B, B19, eight receiving circuits 122 (i.e., eight filters) may be correspondingly disposed to implement filtering processing for the eight low frequency signals. After the filtering processing of these eight filters, eight low-frequency signals B8, B12, B20, B26, B28A, B28B, B, B19 can be output to the second switching unit 123 correspondingly.

In one embodiment, the filter may be a bandpass filter, a lowpass filter, or the like. It should be noted that, in the embodiment of the present application, the type of the filter in each receiving circuit 122 is not limited further, and an appropriate filter may be selected according to the frequency band of the low-frequency signal to be filtered.

The second switch unit 123 includes a plurality of first ends and at least one second end. The first ends of the second switch unit 123 are connected to the receiving circuits 122 in a one-to-one correspondence manner, and are used for receiving the filtered low-frequency signals, and at least one second end of the second switch unit 123 is connected to the input end of the at least one low-noise amplifier 121 in a correspondence manner. The second switch unit 123 is configured to selectively conduct the paths between the at least one second terminal and the plurality of first terminals, so as to simultaneously output at least one low frequency signal to at least one low noise amplifier 121 correspondingly connected thereto.

In one embodiment, the receiving module 120 includes a first low noise amplifier 121, a second switching unit 123, and a plurality of receiving circuits 122. The second switching unit 123 may include a plurality of first terminals and a second terminal. For example, when there are eight receiving circuits 122, the second switching unit 123 may be a radio frequency SP8T switch. Eight selection terminals (i.e., first terminals) of the radio frequency SP8T switch, one selection terminal is correspondingly connected to one receiving circuit 122, a single terminal (i.e., second terminal) of the radio frequency SP8T switch is connected to an input terminal of the first low noise amplifier 121, and an output terminal of the first low noise amplifier 121 is connected to any receiving port LNA OUT. The second switch unit 123 may select the received eight low frequency signals to conduct a path between any one of the receiving circuits 122 and the first low noise amplifier 121, thereby conducting a receiving path of a low frequency signal. The first control unit 140 is connected to the first low noise amplifier 121, and is configured to adjust a gain coefficient of the first low noise amplifier 121 to adjust a cascade noise coefficient of any receiving path.

As shown in fig. 2b, in one embodiment, the receiving module 120 includes a second switching unit 123, a plurality of receiving circuits 122, a second low noise amplifier 121a, a third low noise amplifier 121b, and a third switching unit 124. The second switch unit 123 includes a plurality of first terminals and two second terminals, where the plurality of first terminals are connected to the plurality of receiving circuits 122 in a one-to-one correspondence. An input terminal of the second low noise amplifier 121a is connected to a second terminal of the second switching unit 123; an input terminal of the third low noise amplifier 121b is connected to another second terminal of the second switching unit 123. The second low noise amplifier 121a and the third low noise amplifier 121b may be used to amplify the received low frequency signal.

The third switching unit 124 is connected to the output terminal of the second low noise amplifier 121a, the output terminal of the third low noise amplifier 121b, and the two receiving ports LNA OUT, respectively. Specifically, the third switching unit 124 may be a radio frequency DPDT switch. The two first ends of the radio frequency DPDT switch are respectively connected with the output end of the second low noise amplifier 121a and the output end of the third low noise amplifier 121b, and the two first ends of the radio frequency DPDT switch are respectively connected with the two receiving ports LNA OUT. The third switching unit 124 may be used to selectively output two low frequency signals to the rf transceiver.

As shown in fig. 3, in one embodiment, the second switching unit 123 includes a first SP4T switch 1231 and a second SP4T switch 1232. Wherein four selection terminals of the first SP4T switch 1231 and four selection terminals of the second SP4T switch 1232 serve as the plurality of second terminals of the second switch unit 123, and a single terminal of the first SP4T switch 1231 and a single terminal of the second SP4T switch 1232 serve as the two second terminals of the second switch unit 123. For example, the plurality of receiving circuits 122 connected to the four selection terminals of the first SP4T switch 1231 may include four filters for filtering four low frequency signals of B26, B8, B28A, and B28B, respectively, and the plurality of receiving circuits 122 connected to the four selection terminals of the first SP4T switch 1231 may include four filters for filtering four low frequency signals of B12, B20, B13, and B19, respectively.

Four filters connected to the first SP4T switch 1231 are adjacent to the frequency bands of the four low frequency signals for filtering processing, and four filters connected to the second SP4T switch 1232 are adjacent to the frequency bands of the four low frequency signals for filtering processing. In the embodiment of the present application, the four receiving circuits 122 connected to the first SP4T switch 1231 and the four receiving circuits 122 connected to the second SP4T switch 1232 are not limited, and may be set according to actual requirements.

In one embodiment, the first low noise amplifier 121, the second low noise amplifier 121a, and the third low noise amplifier 121b are gain-adjustable amplifying devices. The first control unit 140 may be configured to adjust gain coefficients of the first low noise amplifier 121, the second low noise amplifier 121a, and the third low noise amplifier 121b, thereby reducing a cascading noise coefficient of each receiving path. Further, the first control unit 140 may also adjust the gain level of each low noise amplifier 121 according to the power value of the low frequency signal. Illustratively, considering an in-band blocking scenario where a large signal may cause in-band blocking, the gain level of each low noise amplifier 121 may be adjusted to avoid damaging the rf transceiver by having its low frequency signal power approach or greater than the rf transceiver's maximum input power.

Based on the radio frequency L-PA Mid device shown in fig. 2a, 2b and 3, the cascade noise coefficient of any receiving path can be reduced by performing gain adjustment on each low noise amplifier 121, 121a, 121b, so as to further improve the sensitivity of the radio frequency L-PA Mid device. Meanwhile, the radio frequency L-PA Mid device can realize the receiving and transmitting control of eight low-frequency signals of B8, B12, B20, B26, B28A, B, B, B and B19, can avoid arranging an extra switching circuit outside the radio frequency L-PA Mid device to support the receiving and transmitting control of overseas frequency bands, for example, B28A, B, B, B and B29, can improve the integration level of the radio frequency L-PA Mid device and reduce the cost, and simultaneously, because the receiving paths of B28A, B, B, B and B29 are arranged inside the radio frequency L-PA Mid device, the link loss of the receiving paths of four low-frequency signals of B28A, B, B, B13 and B29 can be reduced, and further the cascading noise coefficient can be reduced, further the sensitivity of the radio frequency L-PA Mid device can be improved, and the power consumption of the radio frequency L-PA Mid device can be correspondingly reduced.

As shown in fig. 4, in one embodiment, the rf L-PA Mid device further comprises, in addition to the rf L-PA Mid device shown in fig. 2 a: a fourth switching unit 125 and a first attenuator 126. Specifically, the fourth switch units 125 are respectively connected to the output ends of the first low noise amplifiers 121, and at least one receiving port LNA OUT is connected. The first attenuator 126 is connected to the fourth switching unit 125, and is used for attenuating the low frequency signal output by the first low noise amplifier 121. Specifically, the fourth switch unit 125 may be a rf SPDT switch, where a first end of the rf SPDT switch is connected to the output end of the first low noise amplifier 121, a second end of the rf SPDT switch is connected to a receiving port LNA OUT through the first attenuator 126, and another second end of the rf SPDT switch is directly connected to another receiving port LNA OUT. The fourth switching unit 125 may be used to selectively turn on the direct communication path between the first low noise amplifier 121 and a receiving port LNA OUT, and may also be used to selectively turn on the receiving path where the first attenuator 126 is located.

Optionally, the fourth switching unit 125 may further include a rf DPDT switch, where two first ends of the rf DPDT switch are respectively connected to a second end of the rf SPDT switch and the first attenuator 126, and two first ends of the rf DPDT switch are respectively connected to two receiving ports LNA OUT.

In the embodiment of the present application, the type and number of the fourth switch units 125 are not limited, as long as the receiving path where the first attenuator 126 is located can be selectively turned on.

In the rf L-PA Mid device in this embodiment, a first attenuator 126 is disposed between the output end of the first low noise amplifier 121 and the receiving port LNA OUT, and if the received low frequency signal is a high power signal, the attenuation coefficient of the first attenuator 126 may be correspondingly adjusted to increase the attenuation amount of the low frequency signal, so as to avoid adverse effects caused by the excessive power on the rf L-PA Mid device and/or the rf transceiver.

As shown in fig. 5, in one embodiment, the low noise amplifier 121 circuit further includes a fifth switching unit 127 and a second attenuator 128 on the basis of the radio frequency L-PA Mid device shown in fig. 3. Wherein, the control end of the fifth switch unit 127 is connected to the output end of the second low noise amplifier 121a, and a selection end of the fifth switch unit 127 is connected to the third switch unit 124; the other selection terminal of the fifth switching unit 127 is connected to the other second terminal of the third switching unit 124 via a second attenuator 128.

Specifically, the fifth switching unit 127 may be a rf SPDT switch, and the third switching unit 124 is a rf 3P3T switch. The first end (i.e., the control end) of the rf SPDT switch is connected to the output end of the second low noise amplifier 121a, a second end (i.e., a selection end) of the rf SPDT switch is connected to a second end of the rf 3P3T switch, another second end (i.e., another selection end) of the rf SPDT switch is connected to another second end of the third switch unit 124 via the second attenuator 128, and a second end of the rf 3P3T switch is connected to the output end of the third low noise amplifier 121 b. The fifth switch unit 127 may be used to selectively turn on the direct communication path between the second low noise amplifier 121a and a receiving port LNA OUT, or may be used to selectively turn on the receiving path where the second attenuator 128 is located.

In the rf L-PA Mid device in this embodiment, a second attenuator 128 is disposed between the output end of the second low noise amplifier 121a and the receiving port LNA OUT, and if the received low frequency signal is a high power signal, the attenuation coefficient of the second attenuator 128 may be correspondingly adjusted to increase the attenuation amount of the low frequency signal, so as to avoid adverse effects caused by the excessively high power on the rf L-PA Mid device and/or the rf transceiver.

In one embodiment, the radio frequency L-PA Mid device further comprises a sixth switching unit and a third attenuator on the basis of the radio frequency L-PA Mid device as shown in FIG. 4. Wherein, the control end of the sixth switch unit is connected with the output end of the third low noise amplifier 121b, and a selection end of the sixth switch unit is connected with the third switch unit 124; the other selection terminal of the sixth switching unit is connected to the other second terminal of the third switching unit 124 via a third attenuator. The sixth switching unit may be used to selectively turn on the direct communication path between the third low noise amplifier 121b and a receiving port LNA OUT, or may be used to selectively turn on the receiving path where the third attenuator is located.

In the rf L-PA Mid device in this embodiment, a third attenuator is disposed between the output end of the third low noise amplifier 121b and the receiving port LNA OUT, and if the received low frequency signal is a high power signal, the attenuation coefficient of the third attenuator may be correspondingly adjusted to increase the attenuation amount of the low frequency signal, so as to avoid adverse effects caused by the excessively high power on the rf L-PA Mid device and/or the rf transceiver.

In one embodiment, the rf L-PA Mid device may further include a second attenuator 128, a third attenuator, a fifth switching unit 127, and a sixth switching unit on the basis of the rf L-PA Mid device shown in fig. 4. That is, the second attenuator 128 is disposed between the output end of the second low noise amplifier 121a and the receiving port LNA OUT, and the third attenuator is disposed between the output end of the third low noise amplifier 121b and the receiving port LNA OUT, if the received low frequency signal is a high power signal, the attenuation coefficients of the second attenuator 128 and the third attenuator can be correspondingly adjusted to increase the attenuation amount of the low frequency signal, so as to avoid adverse effects caused by the over-high power on the radio frequency L-PA Mid device and/or the radio frequency transceiver.

As shown in fig. 6 and 7, in one embodiment, the transmitting module 110 includes a first power amplifier 111, a seventh switching unit 112, and a plurality of transmitting circuits 113. The input end of the first power amplifier 111 is connected to a transmitting port 4G LB RFIN, and is used for amplifying the received low frequency signal.

The seventh switching unit 112 includes a first terminal and a plurality of second terminals. The first end of the seventh switch unit 112 is connected to the output end of the first power amplifier 111, and the second ends of the seventh switch unit 112 are connected to the transmitting circuits 113 in a one-to-one correspondence manner. The seventh switch unit 112 is used for selectively conducting the path between the first terminal and any second terminal. An input terminal of the transmitting circuit 113 is correspondingly connected to a second terminal of the seventh switching unit 112, and an output terminal of the transmitting circuit 113 is correspondingly connected to a first terminal of the first switching unit 130. The transmitting circuits 113 are used for filtering the low-frequency signals amplified by the first power amplifier 111, and the frequency bands of the low-frequency signals output by the transmitting circuits 113 are different.

Specifically, each transmitting circuit 113 may include a filter. The filter can perform filtering processing on the received low-frequency signal, wherein the filter only allows the low-frequency signal of a preset frequency band to pass. For example, if the frequency bands of the plurality of low frequency signals may be eight different frequency bands of B8, B12, B20, B26, B28A, B28B, B, B19, eight transmitting circuits 113 (i.e., eight filters) may be correspondingly disposed to implement filtering processing for the eight low frequency signals. After the filtering processing of the eight filters, eight low-frequency signals B8, B12, B20, B26, B28A, B28B, B, B19 can be output to the first switching unit 130 correspondingly.

In one embodiment, the filter may be a bandpass filter, a lowpass filter, or the like. It should be noted that, in the embodiment of the present application, the type of the filter in each transmitting circuit 113 is not limited further, and an appropriate filter may be selected according to the frequency band of the low-frequency signal to be filtered.

Wherein the transmitting circuit 113 and the receiving circuit 122 are correspondingly arranged in pairs. That is, one transmitting circuit 113 and one receiving circuit 122 need to be provided for each low-frequency signal. That is, for each low frequency signal, two filters need to be provided, one for filtering the low frequency signal in the reception path and the other for filtering the low frequency signal in the transmission path. For example, if the frequency bands of the plurality of low-frequency signals are eight different frequency bands of B8, B12, B20, B26, B28A, B28B, B, B19, eight pairs of the transmitting circuit 113 and the receiving circuit 122 are required, that is, 16 filters are required. The output terminal of the transmitting circuit 113 and the input terminal of the receiving circuit 122 of each pair share the same port, that is, eight ports are included, and the eight ports are connected to eight first terminals of the first switch in a one-to-one correspondence.

Based on the rf L-PA Mid device shown in fig. 7, the following description will take the control of B28B signal transmission and reception as an example:

emission control: the low-frequency signal enters through the transmitting port 4G LB RFIN of the L-PA Mid device, is amplified by the first power amplifier 111 and then is output to a single port (namely a second end) of the seventh switch unit 112, the receiving path of the B28B signal is conducted by the seventh switch unit 112, the low-frequency signal is filtered by a filter in the transmitting circuit 113 and then is output to the first end of the first switch unit 130, the receiving channel of the B28B signal is conducted by the first switch unit 130, and then the B28B signal is output to the antenna port ANT, so that the transmitting control of the B28B signal is realized.

And (3) receiving control: the low-frequency signal enters through an antenna port ANT of the L-PA Mid device, is switched to a receiving circuit 122 of the B28B through a first switch unit 130, is filtered by a corresponding filter, and then outputs the B28B signal to a first radio frequency SP4T switch, the receiving path of the B28B signal is conducted through the first radio frequency SP4T switch to be input to a second low-noise amplifier 121a, the output end of the second low-noise amplifier 121a is switched to a third switch unit 124 through a fifth switch unit 127, and the third switch unit 124 is switched to a receiving port LNA OUT to realize the receiving control of the B28B signal, or is switched to a second attenuator 128 through the fifth switch unit 127 and then is switched to the receiving port LNA OUT through the third switch unit 124 to realize the receiving control of the B28B signal.

As shown in fig. 6 and 7, in one embodiment, the rf L-PA Mid device is further configured with a coupling-out port CLPOUT, and the rf L-PA Mid device further includes a coupling circuit 150 disposed in the transmit path. The coupling circuit 150 is configured to couple the low frequency signal in the transmit path to output a coupled signal via the coupling output port CLPOUT, and the output coupled signal can be used to measure the forward coupling power and the reverse coupling power of the low frequency signal. Specifically, the coupling circuit 150 includes a coupling unit and a coupling switch. The coupling unit comprises an input end, an output end, a first coupling end and a second coupling end. Meanwhile, the coupling unit further comprises a main line extending between the input end and the output end, and a sub-line extending between the first coupling end and the second coupling end.

The input end of the coupling unit is connected with the first switch unit 130, the output end of the coupling unit 341 is connected with the antenna port ANT, and the first coupling end is used for coupling the low-frequency signal received by the input end and outputting a forward coupling signal; and the second coupling end is used for coupling the reflected signal of the low-frequency signal received by the output end and outputting a reverse coupling signal. The forward power information of the low-frequency signal can be detected based on the forward coupling signal output by the first coupling end; based on the reverse coupling signal output by the second coupling end, the reverse power information of the low-frequency signal can be correspondingly detected, and the detection mode is defined as a reverse power detection mode.

The coupling switch is respectively connected with the first coupling end, the second coupling end and the coupling output port CLPOUT, and is used for selectively conducting the first coupling path of the first coupling end and the coupling output port CLPOUT to realize detection of forward power of the low-frequency signal, and defining the detection mode as a reverse power detection mode, or conducting the second coupling path of the second coupling end and the coupling output port CLPOUT to realize detection of reverse power of the low-frequency signal, and defining the detection mode as a reverse power detection mode. That is, the coupling switch is used to switch between the forward power detection mode and the reverse power detection mode.

In this embodiment, only one coupling output port CLPOUT is provided for the rf L-PA Mid device, and because the low frequency signals of multiple frequency bands are not transmitted at the same time, one coupling output port CLPOUT can also meet the communication requirement, and also reduce the complexity of the rf routing in the rf L-PA Mid device, and simultaneously improve the isolation performance of each routing of the rf L-PA Mid device.

As shown in fig. 8 and 9, in one embodiment, the rf L-PA Mid device further includes a second power amplifier 160, an input terminal of the second power amplifier 160 is connected to the other transmit port 2G HB RFIN, and an output terminal of the second power amplifier 160 is connected to the first terminal of the first switching unit 130, for amplifying a low-band signal of the received 2G signal.

The radio frequency L-PA Mid device in this embodiment can implement emission control of the low-frequency band signal of the 2G signal by setting the second power amplifier 160. The low-frequency band signal of the 2G signal may include a 900M frequency band of a GSM system, an 800M frequency band of a CDMA system, and the like.

In one embodiment, the radio frequency L-PA Mid device is further configured with a high frequency transmit port 4G HB RFIN, and the radio frequency L-PA Mid device further includes a third power amplifier 170, an input terminal of the third power amplifier 170 is connected to the high frequency transmit port 4G HB RFIN, and an output terminal of the third power amplifier 170 is connected to the high frequency antenna port 4G HB OUT, for amplifying a high frequency band signal of the received 2G signal.

The radio frequency L-PA Mid device in this embodiment can implement emission control of the high-band signal of the 2G signal by setting the third power amplifier 170. The low-frequency band signal of the 2G signal may include a 900M frequency band of a GSM system, an 800M frequency band of a CDMA system, and the like.

In one embodiment, the radio frequency L-PA Mid device further includes a second control unit 180. The second control unit 180 is connected to each switch unit, for example, the first switch unit 130, the second switch units 123, …, the seventh switch circuit unit, the first power amplifier 111, the second power amplifier 160, and the third power amplifier 170, and is used for controlling on/off of each switch unit and also for controlling an operating state of each power amplifier.

The second control unit 180 is the same as the first control unit 140, and may be a MIPI-RFFE control unit, which conforms to the control protocol of the RFFE bus.

It should be noted that, in the embodiment of the present application, the control logic of each switch unit is matched with the control logic of the first control unit 140 and the second control unit 180, and in the embodiment of the present application, the specific types of each switch unit, the first control unit 140 and the second control unit 180 are not further limited.

In one embodiment, each device in the rf L-PA Mid device shown in fig. 8 may be integrally packaged in the same package module, and as shown in fig. 10a, each pin in the rf DRX device (package chip) corresponds to a plurality of ports configured by the rf L-PA Mid device one to one. The package specifications of the rf L-PA Mid device are shown in fig. 10b through package integration. Accordingly, each device in the radio frequency L-PA Mid device shown in fig. 9 can be integrally packaged in the same packaging module, and as shown in fig. 11a, each pin in the radio frequency DRX device (packaging chip) corresponds to a plurality of ports configured by the radio frequency L-PA Mid device one by one. The package specifications of the rf L-PA Mid device are shown in fig. 11b through package integration.

The radio frequency L-PA Mid device in the embodiment of the application has high integration level, can reduce the space occupied by each device, and is convenient for miniaturization of the radio frequency L-PA Mid device.

As shown in fig. 12 and 13, the embodiment of the application further provides a radio frequency transceiver system. In one embodiment, a radio frequency transceiver system includes the radio frequency L-PA Mid device 10, the first antenna Ant1, and the radio frequency transceiver 20 of any of the previous embodiments.

In one embodiment, the first antenna Ant1 is connected to an antenna port Ant of the radio frequency L-PA Mid device 10 for transceiving low frequency signals. Specifically, the first antenna Ant1 may be formed using any suitable type of antenna. For example, the first antenna Ant1 may comprise an antenna with a resonating element formed from the following antenna structure: at least one of an array antenna structure, a loop antenna structure, a patch antenna structure, a slot antenna structure, a helical antenna structure, a strip antenna, a monopole antenna, a dipole antenna, and the like. Different types of antennas may be used for different frequency bands and combinations of frequency bands. In the embodiment of the present application, the type of the first antenna Ant1 is not further limited.

By arranging the rf L-PA Mid device 10 in any of the foregoing embodiments, the rf transceiver system can reduce the link loss of the low-frequency signal receiving path, and further reduce the cascade noise factor of the receiving path, so as to improve the sensitivity of the rf transceiver system.

According to the requirements of the communication protocol 3GPP, the performance index requirements of the sensitivity for the partial frequency band under the 5MHz test bandwidth are shown in the following table 1.

Table 1 sensitivity index requirements of 3gpp protocol

Frequency band	B5	B8	B12	B13	B20	B28B	B28B
								Sensitivity (dBm)	-98	-97	-97	-97	-97	-98.5	-98.5

The rf transceiver system shown in fig. 12 is constructed based on the rf L-PA Mid device 10 shown in fig. 9. The rf transceiver system shown in fig. 12 illustrates the working principle of the B28B signal:

emission control: the transmission signal is output from the radio frequency transceiver 20 to the receiving port LNA OUT of the radio frequency L-PA Mid device 10, amplified by the first power amplifier 111, then to the single port of the seventh switching unit 112, switched to the transmission path of the B28B signal, the B28B signal after being filtered by the filter is output to the B28B channel of the first switching unit 130, switched to the single port of the first switching unit 130, and then output to the first antenna ANT1 via the antenna port ANT of the radio frequency L-PA Mid device 10.

And (3) receiving control: the receiving signal is switched from the first antenna Ant1 to the antenna port Ant of the radio frequency L-PA Mid device 10, the first switching unit 130 switches to the B28B channel, the B28B signal after being filtered by the filter is output to the receiving path of the B28B signal, the receiving path of the B28B signal is conducted through the first radio frequency SP4T switch to be input to the second low noise amplifier 121a, then the output end of the second low noise amplifier 121a is switched to the third switching unit 124 through the fifth switching unit 127, and then the third switching unit 124 switches to the radio frequency transceiver 20, or the fifth switching unit 127 switches to the second attenuator 128 and then the third switching unit 124 switches to the radio frequency transceiver 20.

And combining the sensitivity calculation formula, and when the bandwidth of the working frequency band is determined, the noise coefficient of the receiving path directly influences the sensitivity index of the radio frequency receiving and transmitting system. Thus, the noise figure of the receive path of the B28B signal is analyzed as shown in table 2:

table 2 original scheme receive link budget

In table 2, the insertion loss of the first antenna Ant1 to the rf L-PA Mid device 10, including the antenna socket, the combiner, the switch and the trace, is passive loss of the whole link, and the passive loss is 1.3-1.6 dB in the frequency band of 699-915 MHz. The insertion loss of the first switching unit 130, the first rf SP4T switch, and the third switching unit 124 are shown in tables 3-5. The noise figure of the second low noise amplifier 121a is shown in table 6.

TABLE 3 first switching element (RF SP8T switch) insertion loss

Frequency of	Insertion loss
		704～960	0.65
1710～1980	0.8
		2110～2180	0.9

TABLE 4 first RF SP4T switch insertion loss

Frequency of	Insertion loss
		698～960	0.4
1710～1980	0.5
		2110～2180	0.5

TABLE 5 third switching element (RF 3P3T switch) insertion loss

Frequency of	Insertion loss
		704～960	0.7
1710～1980	0.8
		2110～2180	0.9

TABLE 6 second Low noise Amplifier parameter information

Device and method for manufacturing the same	Gain (dB)	Noise figure (dB)
			Index (I)	15.5	3

Trace 1 may be understood as a trace between the rf L-PA Mid device 10 and the rf transceiver 20 with an insertion loss of about 1dB; the noise figure of the radio frequency transceiver 20 is 10dB. As shown in Table 2, the sensitivity is-101.5 dBm/5MHz, which is improved by 1.4dB compared with the traditional radio frequency transceiver system; meanwhile, the sensitivity index of the radio frequency receiving and transmitting system in the embodiment is higher than the requirement of-101 dBm/5MHz required by research and development.

The effect of the second low noise amplifier 121a and the second attenuator 128 of the B28B signal receiving channel on the sensitivity index in response to different interference signals is calculated according to the receiving path budget of table 2, as shown in table 7.

TABLE 7 sensitivity data

As can be seen from the analysis of the data in table 7, as the attenuation amount increases, the effect of the increase in attenuation of the second attenuator 128 on the deterioration of sensitivity is greater than that of the decrease in gain of the second low noise amplifier 121 a; it follows that, in order to cope with the blocking large signal, the gain can be reduced by the second low noise amplifier 121a, and the second attenuator 128 is not required. The rf transceiver system shown in fig. 12 reduces the second attenuator 128 and the fifth switching unit 127, and thus makes space for the layout of other modules, which is beneficial to the performance optimization and also reduces the cost.

As shown in fig. 14 and 15, in one embodiment, the radio frequency transceiver system may further include a second antenna Ant2, where the second antenna Ant2 is connected to the high frequency transmission port 4G LB RFIN of the radio frequency L-PA Mid device 10 in the foregoing embodiment, and is configured to transmit and receive 2G high frequency signals.

The radio frequency receiving and transmitting system in the embodiment comprises the first antenna Ant1 and the second antenna Ant2, so that the receiving and transmitting control of a plurality of low-frequency signals can be realized, the transmitting control of a high-frequency band signal in a 2G signal can be realized, and the wireless communication performance of the radio frequency receiving and transmitting system is improved.

The embodiment of the application also provides the communication equipment, and the radio frequency receiving and transmitting system in any embodiment is arranged on the communication equipment, so that the sensitivity of the communication equipment for receiving the low-frequency signals can be improved, and the wireless communication performance of the communication equipment is further improved.

The foregoing examples illustrate only a few embodiments of the application, which are described in detail and are not to be construed as limiting the scope of the application. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of protection of the present application is to be determined by the appended claims.

Claims

1. A radio frequency L-PA Mid device configured with at least one transmit port and a plurality of receive ports for connection to a radio frequency transceiver and at least one antenna port for connection to an antenna, the radio frequency L-PA Mid device being of a packaging structure, the radio frequency L-PA Mid device comprising:

the first control unit is connected with at least one low-noise amplifier and is used for adjusting the gain coefficient of the low-noise amplifier so as to reduce the cascade noise coefficient of at least one low-frequency signal receiving path; wherein,

the low-frequency signal receiving path is composed of the antenna port, the first switch unit, a low-noise amplifier of the receiving module and the receiving port which are cascaded.

2. The radio frequency L-PA Mid device according to claim 1, wherein said receiving module further comprises:

The receiving circuits are correspondingly connected with a first end of the first switch unit, are used for filtering the received low-frequency signals and are different in frequency band of the low-frequency signals output by the receiving circuits;

and the second switch unit is respectively connected with the receiving circuits and the input end of at least one low-noise amplifier, and is used for receiving a plurality of low-frequency signals and selecting at least one low-frequency signal for output.

3. The rf L-PA Mid device of claim 2, wherein at least one of said low noise amplifiers comprises:

the input end of the first low-noise amplifier is connected with the second switch unit, and the output end of the first low-noise amplifier is connected with one receiving port.

4. The rf L-PA Mid device according to claim 2, wherein said second switching unit comprises a plurality of first terminals and two second terminals, a plurality of said first terminals being connected to a plurality of said receiving circuits in one-to-one correspondence; wherein at least one of the low noise amplifiers comprises:

the input end of the second low-noise amplifier is connected with a second end of the second switch unit;

The input end of the third low-noise amplifier is connected with the other second end of the second switch unit;

and the third switch unit is respectively connected with the output end of the second low-noise amplifier, the output end of the third low-noise amplifier and the two receiving ports and is used for selectively outputting the low-frequency signals of the two frequency bands to the radio-frequency transceiver.

5. The rf L-PA Mid device according to claim 4, wherein said second switching unit comprises:

the control end of the first SP4T switch is connected with the input end of the second low-noise amplifier, and a plurality of selection ends of the first SP4T switch are connected with a first number of receiving circuits in a one-to-one correspondence manner;

the control end of the second SP4T switch is connected with the input end of the third low-noise amplifier, and a plurality of selection ends of the second SP4T switch are connected with a second number of receiving circuits in one-to-one correspondence; wherein the sum of the first number and the second number is less than or equal to the sum of the receiving circuits.

6. The rf L-PA Mid device of claim 3, wherein said rf L-PA Mid device further comprises:

The fourth switching unit is respectively connected with the output end of the first low-noise amplifier and at least one receiving port;

and the first attenuator is connected with the fourth switching unit and is used for attenuating the low-frequency signal output by the first low-noise amplifier.

7. The rf L-PA Mid device of claim 4, wherein said rf L-PA Mid device further comprises:

the control end of the fifth switch unit is connected with the output end of the second low-noise amplifier, and the first selection end of the fifth switch unit is connected with the third switch unit;

and the second attenuator is connected with the first selection end of the fifth switching unit and used for attenuating the low-frequency signal output by the second low-noise amplifier.

8. The rf L-PA Mid device of claim 7, wherein said rf L-PA Mid device further comprises:

the control end of the sixth switching unit is connected with the output end of the third low-noise amplifier, and the first selection end of the sixth switching unit is connected with the third switching unit;

And the third attenuator is connected with the first selection end of the sixth switching unit and used for attenuating the low-frequency signal output by the third low-noise amplifier.

9. The radio frequency L-PA Mid device according to claim 1, wherein said transmitting module comprises:

the input end of the first power amplifier is connected with one transmitting port and is used for amplifying the received low-frequency signal;

the transmitting circuits are used for carrying out filtering processing on the received low-frequency signals, and the frequency bands of the low-frequency signals output by each transmitting circuit are different;

and a seventh switching unit, wherein a first end of the seventh switching unit is connected with the output end of the first power amplifier, a plurality of second ends of the seventh switching unit are correspondingly connected with the input end of the transmitting circuit one by one, and the seventh switching unit is used for selectively conducting a passage between the first power amplifier and any transmitting circuit.

10. The radio frequency L-PA Mid device according to any one of claims 1-9, wherein the frequency band of the low frequency signal comprises: b8, B12, B20, B26, B28A, B28B, B and B19 bands.

11. The rf L-PA Mid device of claim 1, wherein said rf L-PA Mid device further comprises:

and the input end of the second power amplifier is connected with the other transmitting port, and the output end of the second power amplifier is connected with the first end of the first switch unit and is used for amplifying the received 2G low-frequency signal.

12. The rf L-PA Mid device according to claim 1, wherein said rf L-PA Mid device is further configured with a high frequency transmit port and a high frequency antenna port, said rf L-PA Mid device further comprising:

and the input end of the third power amplifier is connected with one high-frequency transmitting port, and the output end of the third power amplifier is connected with the high-frequency antenna port and is used for amplifying the received 2G high-frequency signal.

13. The rf L-PA Mid device of claim 1, wherein the rf L-PA Mid device is further configured with a coupling-out port, the rf L-PA Mid device further comprising:

and the coupling circuit is arranged in the transmitting path and used for coupling the low-frequency signals in the transmitting path so as to output coupling signals through the coupling output port.

14. A radio frequency transceiver system, comprising:

the radio frequency L-PA Mid device of any one of claim 1-13,

15. The radio frequency transceiver system of claim 14, wherein the radio frequency L-PA Mid device is configured with a high frequency transmit port, the radio frequency transceiver system further comprising:

and the second antenna is connected with the high-frequency transmitting port and is used for receiving and transmitting 2G high-frequency signals.

16. A communication device comprising a radio frequency transceiver system as claimed in any one of claims 14-15.