CN114928373B

CN114928373B - Circuit for improving port isolation, radio frequency electronic switch and terminal

Info

Publication number: CN114928373B
Application number: CN202210316418.8A
Authority: CN
Inventors: 葛谋; 吴斌
Original assignee: Xi'an Lingchuang Electronic Technology Co ltd
Current assignee: Xi'an Lingchuang Electronic Technology Co ltd
Priority date: 2022-03-28
Filing date: 2022-03-28
Publication date: 2023-10-13
Anticipated expiration: 2042-03-28
Also published as: CN114928373A

Abstract

A circuit for improving port isolation, a radio frequency electronic switch and a terminal, the circuit comprises: the signal transmission circuit comprises an input end, a first output end and a second output end, wherein a first diode and a second capacitor are sequentially connected in series between the input end and the first output end, a second diode and a fifth capacitor are sequentially connected in series between the input end and the second output end, and a first capacitor is connected between a common node of the first diode and the second diode and the input end; the isolation circuit comprises a first isolation module, a second isolation module and a load absorption structure, wherein the first isolation module and the second isolation module are provided with a first common node, one end of the load absorption structure is connected to the first common node, and the other end of the load absorption structure is grounded. According to the isolation circuit, through the effect of the isolation circuit formed by the common combination of the first isolation module, the second isolation module and the load absorption structure, the isolation degree between all ports in the radio frequency electronic switch is improved, and the problem of electromagnetic compatibility caused by lower port isolation degree is avoided.

Description

Circuit for improving port isolation, radio frequency electronic switch and terminal

Technical Field

The disclosure relates to the technical field of radio frequency circuits, and in particular relates to a circuit for providing port isolation, a radio frequency electronic switch and a terminal.

Background

Along with the development of technology at home and abroad, the communication electronic products have more and more powerful functions, and from the initial simulation of simple digital signals to the development of multi-frequency bands, high-speed frequency modulation and networking, electronic devices also rapidly develop, so that the traditional transceiving conversion switch cannot meet the increasing demands of users.

Because the isolation of the traditional switching devices such as a transceiver change-over switch, a relay and the like is low, and because the poor electromagnetic compatibility can be caused by the low isolation of a port, the design requirement of a system can not be met, and therefore, a radio frequency electronic switch with high isolation is urgently needed.

It should be noted that the information disclosed in the above background section is only for enhancing understanding of the background of the present disclosure and thus may include information that does not constitute prior art known to those of ordinary skill in the art.

Disclosure of Invention

The purpose of the present disclosure is to overcome the shortcomings of the prior art, and provide a circuit radio frequency electronic switch and a terminal for improving port isolation.

Other features and advantages of the present disclosure will be apparent from the following detailed description, or may be learned in part by the practice of the disclosure.

According to one aspect of the present disclosure, there is provided a circuit for improving port isolation, comprising:

the signal transmission circuit comprises an input end, a first output end and a second output end, wherein a first diode and a second capacitor are sequentially connected in series between the input end and the first output end, a second diode and a fifth capacitor are sequentially connected in series between the input end and the second output end, and a first capacitor is connected between a common node of the first diode and the second diode and the input end;

the isolation circuit comprises a first isolation module, a second isolation module and a load absorption structure, wherein the first isolation module and the second isolation module are provided with a first common node, one end of the load absorption structure is connected with the first common node, and the other end of the load absorption structure is grounded;

one end of the first blocking module is connected between the first diode and the second capacitor, and the second blocking module is connected between the second diode and the fifth capacitor.

In some embodiments of the disclosure, based on the foregoing scheme, the first blocking module includes a third diode, a fifth diode, and a third capacitor connected in series in sequence.

In some embodiments of the disclosure, based on the foregoing scheme, the third diode and the fifth diode have a second common node, and the first diode is connected to the second common node.

In some embodiments of the disclosure, based on the foregoing solution, the circuit further includes a seventh diode, one end of the seventh diode is connected to a third common node, another end of the seventh diode is grounded, and the third common node is a common node of the second capacitor and the third diode.

In some embodiments of the disclosure, based on the foregoing solution, the second blocking module includes a fourth diode, a sixth diode, and a fourth capacitor connected in series in sequence.

In some embodiments of the disclosure, based on the foregoing, the fourth diode and the sixth diode have a fourth common node, and the second diode is connected to the fourth common node.

In some embodiments of the disclosure, based on the foregoing solution, the circuit further includes an eighth diode, one end of the eighth diode is connected to the fifth common node, another end of the eighth diode is grounded, and the fifth common node is a common node of the fifth capacitor and the fourth diode.

In some embodiments of the disclosure, based on the foregoing, the load absorbing structure is a load absorbing resistor.

According to another aspect of the present disclosure, there is provided a radio frequency electronic switch comprising:

the radio frequency electronic switch comprises a radio frequency electronic switch body, wherein the radio frequency electronic switch body comprises a signal transmission circuit, and the signal transmission circuit is provided with an input end and a plurality of output ends;

and the isolation circuit is connected to the signal transmission circuit and is used for improving the port isolation between the input end and the plurality of output ends or between the plurality of output ends.

According to another aspect of the present disclosure, there is provided a terminal, the terminal at least includes a processor, a memory, a radio frequency circuit, and a radio frequency electronic switch as described above, where the memory and the radio frequency circuit are connected to the processor, the radio frequency electronic switch is connected to the radio frequency circuit, the processor is used to process a signal, the memory is used to store the signal, the radio frequency circuit is used to receive and send the signal, and the radio frequency electronic switch is used to control on-off of the signal in the radio frequency circuit.

According to the circuit for improving the port isolation, on one hand, the isolation circuit is arranged in the signal transmission circuit, leakage signals between all output ports in the signal transmission circuit are isolated through the first isolation module and the second isolation module in the isolation circuit, and the isolation between all the output ports is improved; on the other hand, the isolation circuit also comprises a load absorption structure connected with the first isolation module and the second isolation module, and the load absorption structure absorbs leakage signals which are not isolated completely in the first isolation module and the second isolation module, so that the isolation degree between all ports is further improved; through the combined action of the isolation module and the load absorption structure, the isolation between the input end and the output port of the radio frequency electronic switch and the isolation between the output ports are improved, the electromagnetic compatibility problem caused by low port isolation is avoided, and the performance of the device is improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure. It will be apparent to those of ordinary skill in the art that the drawings in the following description are merely examples of the disclosure and that other drawings may be derived from them without undue effort.

Fig. 1 is a schematic structural diagram of a serial architecture radio frequency electronic switch in an exemplary embodiment of the present disclosure.

Fig. 2 is a schematic structural diagram of a parallel architecture rf electronic switch in an exemplary embodiment of the present disclosure.

Fig. 3 is a schematic diagram of a solution structure of a serial-parallel architecture radio frequency electronic switch according to an exemplary embodiment of the disclosure.

Fig. 4 is a schematic structural diagram of a circuit for improving port isolation in an exemplary embodiment of the present disclosure.

Fig. 5 is an equivalent circuit diagram of a first signal transmission circuit in an exemplary embodiment of the present disclosure.

Fig. 6 is an equivalent circuit diagram of a second signal transmission circuit in an exemplary embodiment of the present disclosure.

Fig. 7 is a schematic diagram of a radio frequency electronic switch with isolation circuitry in an exemplary embodiment of the present disclosure.

Fig. 8 is a schematic structural view of a terminal in an exemplary embodiment of the present disclosure.

Wherein reference numerals are as follows:

100: a radio frequency electronic switch body; 101: a signal transmission circuit; 102: an isolation circuit;

10: an input end; 20: and an output end: 21: a first output terminal; 22: a second output terminal;

1: a first barrier module; 2: a second barrier module; 3: a load absorbing structure;

d1: a first diode; d2: a second diode; d3: a third diode;

d4: a fourth diode; d5: a fifth diode; d6: a sixth diode;

d7: a seventh diode; d8: an eighth diode; c1: a first capacitor;

c2: a second capacitor; and C3: a third capacitor; and C4: a fourth capacitor;

c5: a fifth capacitor; 31: a first common node; 32: a second common node;

33: a third common node; 34: a fourth common node; 35: and a fifth common node.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many 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, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus detailed descriptions thereof will be omitted. Furthermore, the drawings are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale.

The terms "a," "an," "the," "said" and "at least one" are used to indicate the presence of one or more elements/components/etc.; the terms "comprising" and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. in addition to the listed elements/components/etc.; the terms "first," "second," and "third," etc. are used merely as labels, and do not limit the number of their objects.

The diode used in the present disclosure may be a normal diode composed of a PN junction, or may be a PIN diode or a diode having other structures, and is preferably a PIN diode. The PIN Diode is formed by adding a thin layer of low-doped Intrinsic (Intrinsic) semiconductor layer between P-type and N-type semiconductor materials, and has wide application from low Frequency to high Frequency due to the presence of the Intrinsic (Intrinsic) layer, and is mainly used in the field of Radio Frequency (RF) for RF switching and RF protection circuits and photodiodes (Photo Diode), wherein the PIN Diode comprises a PIN photodiode and a PIN switching Diode, and the two PIN diodes are suitable for the circuits provided by the present disclosure.

The PIN diode presents impedance characteristics similar to on or off under direct current forward-reverse bias, so that the conversion function of the radio frequency signal channel is controlled, and the total charge of the PIN diode I layer is mainly generated by bias current. Instead of being generated by the instantaneous value of the radio frequency current, the microwave signal is only provided with a linear resistor, the resistance is determined by direct current bias, the resistance is small in the forward bias and close to a short circuit, and the resistance is large in the reverse bias and close to an open circuit. Thus, the PIN diode can be used as a variable impedance element in a radio frequency electronic switch.

The common architecture of the rf electronic switch is a serial architecture, a parallel architecture and a serial-parallel combined architecture, the specific structures of which are shown in fig. 1, 2 and 3, wherein fig. 1 is a schematic diagram of the serial architecture of the rf electronic switch, the input end of the rf electronic switch is respectively connected with two output ports, a PIN diode is connected in series between the input end 10 and the first output end 21, after bias voltage is applied to the input end 10, the PIN diode is in a conducting state, so that the input end 10 and the first output end 21 are in a communicating state, and similarly, the input end 10 and the second output end 22 have the same structure, and after the switch is disconnected, when the PIN diode is in a reverse cut-off high-resistance state, due to the reflection effect of the PIN diode on the rf signal in the rf circuit, the rf signal leakage phenomenon exists in the circuit, so that the isolation between the first output end 21 and the second output end 22 is lower.

In the schematic diagram of the parallel architecture of the rf electronic switch shown in fig. 2, PIN diodes are not connected between the input terminal 10 and the first output terminal 21 and the second output terminal 22, so that after a bias voltage is applied to the input terminal 10, the input terminal and the output ports are directly conducted, and after the switch is turned off, when a reflected leakage signal exists between the two output ports, the reflected leakage signal is transmitted to a ground state through the PIN diodes connected in parallel in the circuit, so that the reflected signal is absorbed, but the isolation between the two output ports achieved by the parallel architecture is not high.

In the serial-parallel architecture of the rf electronic switch shown in fig. 3, by combining the serial architecture and the parallel architecture, the isolation of two output ports is improved through the combined action of the two architectures, but the port isolation of the architecture is not ideal.

Therefore, the present disclosure provides a circuit for improving port isolation, which can improve port isolation of a radio frequency electronic switch through a new circuit architecture, and provides a radio frequency electronic switch with high port isolation.

The disclosed embodiment provides a circuit for improving port isolation, as shown in fig. 4, the circuit includes: a signal transmission circuit and an isolation circuit.

The signal transmission circuit includes an input end 10, a first output end 21 and a second output end 22, a first diode D1 and a second capacitor C2 are sequentially connected in series between the input end 10 and the first output end 21, a second diode D2 and a fifth capacitor C5 are sequentially connected in series between the input end 10 and the second output end 22, and a first capacitor C1 is connected between a common node of the first diode D1 and the second diode D2 and the input end 10.

The first capacitor C1, the second capacitor C2 and the fifth capacitor C5 are radio frequency path coupling capacitors, and provide radio frequency paths to isolate different dc bias voltages, in some embodiments, the first capacitor C1, the second capacitor C2 and the fifth capacitor C5 may be radio frequency path direct-blocking patch capacitors, and may bear passing power and high voltage, specific types of the three capacitors may be selected specifically according to an operating frequency band of the radio frequency electronic switch, and the lower the operating frequency band of the radio frequency electronic switch, the larger the required capacitance value, and in general, as radio frequency path coupling capacitors, the first capacitor C1, the second capacitor C2 and the fifth capacitor C5 may be capacitors with parameters of package 1812, withstand voltage 300V and capacity of 0.01 μf, but the capacitors of the above types are only exemplary references, may be selected specifically according to specific types of the use requirements of the capacitors, and the disclosure is not limited specifically.

The isolation circuit is shown in a large rectangular dotted line area of fig. 4, and includes a first isolation module 1 (a small rectangular dotted line area), a second isolation module 2 (a small rectangular dotted line area), and a load absorption structure 3, where the first isolation module 1 and the second isolation module 2 have a first common node 31, one end of the load absorption structure 3 is connected to the first common node 31, and the other end of the load absorption structure 3 is Grounded (GND).

One end of the first blocking module 1 is connected between the first diode D1 and the second capacitor C2, and the second blocking module 2 is connected between the second diode D2 and the fifth capacitor C5.

In some embodiments, the first blocking module 1 includes a third diode D3, a fifth diode D5 and a third capacitor C3 sequentially connected in series, the third diode D3 and the fifth diode D5 have a second common node 32, the first diode D1 is connected to the second common node 32, the first blocking module 1 may be connected between the input terminal 10 and the first output terminal 21 through the connection relationship between the first blocking module 1 and the signal transmission circuit, the circuit between the input terminal 10 and the first output terminal 21 is referred to as a first signal transmission circuit in the present disclosure, and the first blocking module 1 may isolate a leakage signal in the first signal transmission circuit to improve the isolation of the first signal transmission circuit.

In some embodiments, the second blocking module 2 includes a fourth diode D4, a sixth diode D6, and a fourth capacitor C4 sequentially connected in series, the fourth diode D4 and the sixth diode D6 have a fourth common node 34, the second diode D2 is connected to the fourth common node 34, the second blocking module 2 may be connected between the input terminal 10 and the second output terminal 22 through the connection relationship between the second blocking module 2 and the signal transmission circuit, the circuit between the input terminal 10 and the second output terminal 22 is referred to as a second signal transmission circuit in the disclosure, and the second blocking module 2 may isolate a leakage signal in the second signal transmission circuit to improve the isolation of the second signal transmission circuit.

In some embodiments, since the isolation circuit further includes a load absorbing structure 3, the first isolation module 1 and the second isolation module 2 have a first common node 31, one end of the load absorbing structure 3 is connected to the first common node 31, and the other end of the load absorbing structure 3 is Grounded (GND), where the first common node 31 is a common node of the third capacitor C3 in the first isolation module 1 and the fourth capacitor C4 in the second isolation module 2, that is, the load absorbing structure 3 is connected to a common node of the third capacitor C3 and the fourth capacitor C4, after the first isolation module 1 isolates the leakage signal from the first signal transmission circuit, if the leakage signal is still present, the leakage signal can be absorbed by the load absorbing structure 3, so as to further improve the port isolation in the circuit; similarly, after the second blocking module 2 isolates the leakage signal of the first signal transmission circuit, if the leakage signal exists, the leakage signal can be absorbed through the load absorbing structure 3, so that the port isolation in the circuit is further improved.

The third capacitor C3 and the fourth capacitor C4 may be filter capacitors, filter the dc bias voltage, eliminate the interference of signals, and the third capacitor C3 and the fourth capacitor C4 may be packaged 1210, 1206 or 0805, withstand voltage is 300V, and capacity is 0.001 μf, but may also be capacitors of other types or structures according to the capacitor use condition of the actual circuit, which is not particularly limited in this disclosure.

It should be noted that, in the embodiment of the present disclosure, the load absorbing structure 3 may be a load absorbing resistor, the number of load absorbing resistors may be one or more, or may be a combination of a load absorbing resistor and other devices, for example, a load absorbing structure formed by combining a load absorbing resistor and an inductor, or a load absorbing structure formed by combining a load absorbing resistor and a capacitor, which is not limited to a specific structure of the load absorbing structure 3, and needs to satisfy the effect of absorbing the leakage signal.

In addition, if the load absorbing structure adopts a structure of load absorbing resistors, if the number of the load absorbing resistors is multiple, the multiple load absorbing resistors can be connected in series or in parallel in the isolation circuit, further, the load absorbing resistor can adopt a load resistor with a resistance value of 50 ohms, and the load resistor with other resistance values or types can be selected according to specific use needs.

In some embodiments, the signal transmission circuit further includes a seventh diode D7 and an eighth diode D8, one end of the seventh diode D7 is connected to the third common node 33, the other end of the seventh diode D7 is grounded (DND), the third common node 33 is a common node of the second capacitor C2 and the third diode D3, one end of the eighth diode D8 is connected to the fifth common node 35, the other end of the eighth diode is Grounded (GND), and the fifth common node 35 is a common node of the fifth capacitor C5 and the fourth diode D4. The seventh diode D7 and the eighth diode D8 are disposed in the signal transmission circuit, and one ends of the seventh diode D7 and the eighth diode D8 are connected to ground, so that leakage signals generated by different ports are conducted to ground through the seventh diode D7 and the eighth diode D8, and isolation between the ports is improved.

The operation of the signal transmission circuit and the isolation circuit will be described with reference to fig. 4:

1. when the radio frequency signal is transmitted from the input terminal 10 to the first output terminal 21, the signal transmission path is shown in the arrow direction in fig. 5, and the on and off states for the respective diodes shown in fig. 4 are shown in table 1:

D1

D2

D3

D4

D5

D6

D7

D8

conduction

√

Cut-off

√

TABLE 1

Referring to tables 1, 4 and 5, when the input terminal 10 is required to output the rf signal to the first output terminal 21, the input terminal 10 and the first output terminal 21 are in an on state, and the input terminal 10 and the second output terminal 22 are in an off state, at this time, the on and off relationships of the respective components in the signal transmission circuit and the isolation circuit are as follows:

the first diode D1, the third diode D3, the sixth diode D6 and the eighth diode D8 are turned on in the forward direction, the second diode D2, the fourth diode D4, the fifth diode D5 and the seventh diode D7 are turned off in the reverse direction, the radio frequency signal is input from the input terminal 10 and transmitted to the first output terminal 21 through the first capacitor C1, the first diode D1, the third diode D3 and the second capacitor C2, wherein the second diode D2 connected between the input terminal 10 and the second output terminal 22 is in the high impedance state cut-off state, but due to the characteristics of the diodes, a part of leakage signal exists, the fourth diode D4 is also in the cut-off state in the second signal transmission circuit, and the leakage signal can be further intercepted, and furthermore, due to the eighth diode D8 being in the on state, the signal leaked by the fourth diode D4 can be grounded through the eighth diode D8; in the isolation circuit, the leakage signal output by the second diode D2 can be transmitted to the load absorption structure 3 through the sixth diode D6 and the fourth capacitor C4, and is absorbed by the load absorption structure 3 and then grounded, so that the port isolation between the first output terminal 21 and the second output terminal 22 can be effectively improved through the signal propagation path.

2. When the rf signal is transmitted from the input terminal 10 to the second output terminal 22, the signal transmission path is shown in the arrow direction in fig. 6, and the on and off states for the respective diodes shown in fig. 4 are shown in table 2:

D1

D2

D3

D4

D5

D6

D7

D8

cut-off

√

Conduction

√

TABLE 2

Referring to tables 2, 4 and 6, when the input terminal 10 is required to output the radio frequency signal to the second output terminal 22, the input terminal 10 and the second output terminal 22 are in an on state, and the input terminal 10 and the first output terminal 21 are in an off state, at this time, the on and off relationships of the respective components in the signal transmission circuit and the isolation circuit are as follows:

the first diode D1, the third diode D3, the sixth diode D6 and the eighth diode D8 are turned off in the reverse direction, the second diode D2, the fourth diode D4, the fifth diode D5 and the seventh diode D7 are turned on in the forward direction, the radio frequency signal is input from the input terminal 10 and transmitted to the second output terminal 22 through the first capacitor C1, the second diode D2, the fourth diode D4 and the fifth capacitor 5, wherein the first diode D1 connected between the input terminal 10 and the first output terminal 21 is in a high-impedance cut-off state, but due to the characteristics of the diodes, a part of leakage signal exists, the third diode D3 is also in a cut-off state in the first signal transmission circuit, and the leakage signal can be further intercepted, and furthermore, due to the fact that the seventh diode D7 is in a conductive state, the signal leaked by the third diode D3 can be conducted to the ground through the seventh diode D7; in the isolation circuit, the leakage signal output by the first diode D1 can be transmitted to the load absorption structure 3 through the fifth diode D5 and the third capacitor C3, and is absorbed by the load absorption structure 3 and then grounded, so that the port isolation between the two output ends 22 and the first output end 21 can be effectively improved through the signal propagation path.

In some embodiments of the present disclosure, for the rf electronic switch with one input end corresponding to two output ends as shown in fig. 3, the port isolation end is usually in the range of 0-30 dB, and the maximum isolation value is also within 50dB, but in the rf electronic switch provided in the present disclosure, an isolation circuit is added in the signal transmission circuit, so that the port isolation may reach more than 80dB, and compared with the existing rf electronic switch, the port isolation of the present disclosure is improved by more than 60% compared with the existing port isolation, the port isolation improvement effect is significant, and the performance of the device is greatly optimized.

It should be noted that, the above embodiments of the present disclosure all illustrate the isolation circuit and the load absorption structure by taking the signal transmission circuit having one input end and two output ends as examples, but the circuit for improving the isolation provided by the present disclosure is not only suitable for a radio frequency electronic switch with one input end to two output ends, but also suitable for a circuit architecture form with one input end to multiple output ends or multiple input ends to one output end, and according to different numbers of input ends and output ends, the number and architecture of the isolation circuit and the load absorption structure provided by the present disclosure can be correspondingly deformed and combined to achieve the isolation between multiple ports, which is also within the protection scope of the present disclosure.

In addition, the above embodiments of the present disclosure are described in terms of a serial-parallel architecture (as shown in fig. 3) of the rf electronic switch, but the isolation circuit and the load absorption structure provided by the present disclosure are also applicable to rf electronic switches in terms of serial architecture (as shown in fig. 1) or parallel architecture (as shown in fig. 2) and other different architectures, and the isolation circuit and the load absorption structure are correspondingly deformed and connected by different architectures corresponding to different rf electronic switches, so as to achieve a circuit form for improving the port isolation of the rf electronic switch, which is within the scope of the present disclosure.

According to the circuit for improving isolation, the isolation circuit is additionally arranged in the signal transmission circuit in the radio frequency electronic switch, the first isolation module and the second isolation module in the isolation circuit are used for isolating leakage signals between all output ports in the signal transmission circuit respectively, isolation between all ports is improved, in addition, the load absorption structure is additionally arranged in the isolation circuit, the leakage signals of the ports are further absorbed, and isolation between all ports is improved.

The disclosed embodiments also provide a radio frequency electronic switch, as shown in fig. 7, including: a radio frequency electronic switch body 100 and an isolation circuit 102.

The radio frequency electronic switch body 100 comprises a signal transmission circuit 101, wherein the signal transmission circuit 101 is provided with an input end 10 and a plurality of output ends 20; the isolation circuit 102 is connected to the signal transmission circuit 101, and the isolation circuit 102 is connected to the signal transmission circuit 101, so that the port isolation of the radio frequency electronic switch is improved under the combined action of the first blocking module 1, the second blocking module 2 and the load absorbing structure 3 in the isolation circuit 102, and the structural composition and the working principle of the isolation circuit 102 and the signal transmission circuit 101 are as described in the above embodiments of the disclosure, which is not repeated here.

The radio frequency electronic switch provided by the disclosure comprises any radio frequency electronic switch comprising an isolation circuit in the embodiment, has high isolation and excellent device performance, and can be widely applied to various occasions.

The disclosed embodiments also provide a terminal, as shown in fig. 8, which may include Radio Frequency (RF) circuitry 601, memory 602 including one or more computer-readable storage media, input unit 603, display unit 604, sensor 605, audio circuit 606, wireless fidelity (WiFi, wireless Fidelity) module 607, processor 608 including one or more processing cores, and power supply 609. It will be appreciated by those skilled in the art that the terminal structure shown in fig. 8 is not limiting of the terminal and may include more or fewer components than shown, or may combine certain components, or a different arrangement of components. Wherein:

the RF circuit 601 may be used for receiving and transmitting signals during a message or a call, and in particular, after receiving downlink information of a base station, the downlink information is processed by one or more processors 608; in addition, data relating to uplink is transmitted to the base station. Typically, RF circuitry 601 includes, but is not limited to, an antenna, at least one amplifier, a tuner, one or more oscillators, a subscriber identity module (SIM, subscriber Identity Module) card, a transceiver, a coupler, a low noise amplifier (LNA, low Noise Amplifier), a duplexer, and the like. In addition, the RF circuitry 601 may also communicate with networks and other devices through wireless communications. The wireless communication may use any communication standard or protocol including, but not limited to, global system for mobile communications (GSM, global System of Mobile communication), general packet radio service (GPRS, general Packet Radio Service), code division multiple access (CDMA, code Division Multiple Access), wideband code division multiple access (WCDMA, wideband Code Division Multiple Access), long term evolution (LTE, long Term Evolution), email, short message service (SMS, short Messaging Service), and the like.

The memory 602 may be used to store software programs and modules that are stored in the memory 602 for execution by the processor 608 to perform various functional applications and data processing. The memory 602 may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application program (e.g., a sound playing function, an image playing function, etc.) required for at least one function, and the like; the storage data area may store data (such as audio data, phonebooks, etc.) created according to the use of the mobile terminal, etc. In addition, the memory 602 may include high-speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other volatile solid-state storage device. Accordingly, the memory 602 may also include a memory controller to provide access to the memory 602 by the processor 608 and the input unit 603. In the embodiment of the present application, the memory 602 is configured to store a frequency band list corresponding to the isolation control module and a minimum loss mode corresponding to a frequency band.

The input unit 603 may be used to receive input numeric or character information and to generate keyboard, mouse, joystick, optical or trackball signal inputs related to user settings and function control. In some particular embodiments, the input unit 603 may include a touch-sensitive surface, as well as other input devices. The touch-sensitive surface, also referred to as a touch display screen or a touch pad, may collect touch operations thereon or thereabout by a user (e.g., operations thereon or thereabout by a user using any suitable object or accessory such as a finger, stylus, etc.), and actuate the corresponding connection means according to a pre-set program. Alternatively, the touch-sensitive surface may comprise two parts, a touch detection device and a touch controller. The touch detection device detects the touch azimuth of a user, detects a signal brought by touch operation and transmits the signal to the touch controller; the touch controller receives touch information from the touch detection device and converts it into touch point coordinates, which are then sent to the processor 608, and can receive commands from the processor 608 and execute them. In addition, touch sensitive surfaces may be implemented in a variety of types, such as resistive, capacitive, infrared, and surface acoustic waves. The input unit 603 may comprise other input devices in addition to a touch sensitive surface. In particular, other input devices may include, but are not limited to, one or more of a physical keyboard, function keys (e.g., volume control keys, switch keys, etc.), a trackball, mouse, joystick, etc.

The display unit 604 may be used to display information input by a user or information provided to the user and various graphical user interfaces of the terminal, which may be composed of graphics, text, icons, video and any combination thereof.

The display unit 604 may include a display panel, which may be optionally configured in the form of a liquid crystal display (LCD, liquid Crystal Display), an Organic Light-Emitting Diode (OLED), or the like. Further, the touch-sensitive surface may overlay a display panel, and upon detection of a touch operation thereon or thereabout, the touch-sensitive surface is passed to the processor 608 to determine the type of touch event, and the processor 608 then provides a corresponding visual output on the display panel based on the type of touch event. Although in fig. 8 the touch sensitive surface and the display panel are implemented as two separate components for input and output functions, in some embodiments the touch sensitive surface may be integrated with the display panel to implement the input and output functions.

The terminal may also include at least one sensor 605, such as a light sensor, a motion sensor, and other sensors. Specifically, the light sensor may include an ambient light sensor that may adjust the brightness of the display panel according to the brightness of ambient light, and a proximity sensor that may turn off the display panel and/or backlight when the terminal moves to the ear. As one type of motion sensor, the gravity acceleration sensor can detect the acceleration in all directions (generally three axes), and can detect the gravity and direction when stationary, and can be used for applications of recognizing the gesture of a mobile phone (such as horizontal and vertical screen switching, related games, magnetometer gesture calibration), vibration recognition related functions (such as pedometer, knocking) and the like; other sensors such as gyroscopes, barometers, hygrometers, thermometers, infrared sensors, etc. that may also be configured in the terminal are not described in detail herein.

The audio circuit 606, speaker, microphone may provide an audio interface between the user and the terminal. The audio circuit 606 may transmit the received electrical signal after audio data conversion to a speaker, where the electrical signal is converted to a sound signal for output; on the other hand, the microphone converts the collected sound signals into electrical signals, which are received by the audio circuit 606 and converted into audio data, which are processed by the audio data output processor 608 for transmission to, for example, another terminal via the RF circuit 601, or which are output to the memory 602 for further processing. The audio circuit 606 may also include an ear bud jack to provide communication of the peripheral ear bud with the terminal.

WiFi belongs to a short-distance wireless transmission technology, and a mobile terminal can help a user to send and receive emails, browse webpages, access streaming media and the like through a WiFi module 607, so that wireless broadband Internet access is provided for the user. Although fig. 8 shows a WiFi module 607, it is understood that it does not belong to the essential constitution of the terminal, and can be omitted entirely as required within the scope of not changing the essence of the application.

The processor 608 is a control center of the terminal, and connects the entire mobile phone or various parts of the computer using various interfaces and lines, and performs various functions of the terminal and processes data by running or executing software programs and/or modules stored in the memory 602, and calling data stored in the memory 602, thereby performing overall monitoring of the mobile phone. Optionally, the processor 608 may include one or more processing cores; preferably, the processor 608 may integrate an application processor that primarily handles operating systems, user interfaces, applications, etc., with a modem processor that primarily handles wireless communications. It will be appreciated that the modem processor described above may not be integrated into the processor 608.

The terminal also includes a power supply 609 (e.g., a battery) for powering the various components, which may be logically connected to the processor 608 via a power management system so as to provide for managing charging, discharging, and power consumption by the power management system. The power supply 609 may also include one or more of any components, such as a direct current or alternating current power supply, a recharging system, a power failure detection circuit, a power converter or inverter, a power status indicator, and the like.

Although not shown, the terminal may further include a camera, a bluetooth module, etc., which will not be described herein. Specifically, in this embodiment, the processor 608 in the terminal loads executable files corresponding to the processes of one or more application programs into the memory 602 according to the following instructions, and the processor 608 executes the application programs stored in the memory 602, thereby implementing various functions.

The circuit, the radio frequency electronic switch and the terminal for improving the port isolation provided by the embodiment of the application are described in detail, and specific examples are applied to the explanation of the principle and the implementation mode of the application, and the explanation of the above embodiment is only used for helping to understand the method and the core idea of the application; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in light of the ideas of the present application, the present description should not be construed as limiting the present application.

Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of an icon to another component, these terms are used in this specification for convenience only, such as in terms of the orientation of the examples described in the figures. It will be appreciated that if the device of the icon is flipped upside down, the recited "up" component will become the "down" component. When a structure is "on" another structure, it may mean that the structure is integrally formed with the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through another structure.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

Claims

1. A circuit for improving port isolation, comprising:

2. The circuit of claim 1, wherein the first blocking module comprises a third diode, a fifth diode, and a third capacitor in series.

3. The circuit of claim 2, wherein the third diode and the fifth diode have a second common node, and the first diode is connected to the second common node.

4. The circuit for improving port isolation according to claim 3, further comprising a seventh diode, wherein one end of the seventh diode is connected to a third common node, the other end of the seventh diode is grounded, and the third common node is a common node of the second capacitor and the third diode.

5. The circuit of claim 1, wherein the second blocking module comprises a fourth diode, a sixth diode, and a fourth capacitor in series.

6. The circuit of claim 5, wherein the fourth diode and the sixth diode have a fourth common node, and the second diode is connected to the fourth common node.

7. The circuit for improving port isolation according to claim 6, further comprising an eighth diode, wherein one end of the eighth diode is connected to a fifth common node, and the other end of the eighth diode is grounded, and the fifth common node is a common node of the fifth capacitor and the fourth diode.

8. The circuit of claim 1, wherein the load absorbing structure is a load absorbing resistor.

9. A radio frequency electronic switch, comprising:

an isolation circuit as claimed in any of claims 1 to 8, connected in the signal transmission circuit for improving port isolation between the input and the plurality of outputs, or between the plurality of outputs.

10. A terminal comprising at least a processor, a memory, a radio frequency circuit and the radio frequency electronic switch according to claim 9, wherein the memory and the radio frequency circuit are connected to the processor, the radio frequency electronic switch is connected to the radio frequency circuit, the processor is used for processing signals, the memory is used for storing the signals, the radio frequency circuit is used for receiving and transmitting the signals, and the radio frequency electronic switch is used for controlling the on-off of the signals in the radio frequency circuit.