Bridge coupler and communication system

Abstract

The invention provides a bridge coupler and a communication system, which are used for sharing power among different channels and improving the coverage capability under the condition of not increasing the power consumption of equipment. The bridge coupler comprises a first radio frequency input end, a second radio frequency input end, a first radio frequency bridge, a first radio frequency output end, a second radio frequency output end, a first directional coupler, a second directional coupler and a correction end; the first radio frequency input end, the second radio frequency input end and the first radio frequency bridge are respectively connected with two input ends of the radio frequency bridge, and the first radio frequency output end and the second radio frequency output end are respectively connected with two output ends of the radio frequency bridge; the first radio frequency input end is used for acquiring a first signal, the second radio frequency input end is used for acquiring a second signal, the first signal and the second signal are signals obtained by processing the same signal source, and the phase difference between the first signal and the second signal is 90 degrees.

Description

Technical Field

[0001] This application relates to the field of communication technologies, and in particular, to a bridge coupler and a communication system. Background Art

[0002] Power sharing means that the transmit power can flexibly allocate the power ratios of multiple ports between the ports while keeping the total power unchanged. With the large-scale deployment of 5G, 5G faces stronger spatial attenuation of radio frequency signals at higher bandwidths and frequencies. At the same time, the increased power consumption brought by 5G base stations will increase the electricity cost. How to improve the coverage ability without increasing the device power consumption is very important. Summary of the Invention

[0003] This application provides a bridge coupler and a communication system for sharing power between different channels and improving the coverage ability without increasing the device power consumption.

[0004] In a first aspect, an embodiment of this application provides a bridge coupler, which includes a first radio frequency input end, a second radio frequency input end, a first radio frequency bridge, a first radio frequency output end, a second radio frequency output end, a first directional coupler, a second directional coupler, and a calibration end; the first radio frequency input end is connected to the first input end of the first radio frequency bridge, the second radio frequency input end is connected to the second input end of the first radio frequency bridge, the first radio frequency output end is connected to the first output end of the first radio frequency bridge, and the second radio frequency output end is connected to the second output end of the first radio frequency bridge; the through arm of the first directional coupler is connected between the first radio frequency input end and the first input end of the first radio frequency bridge, and the coupled arm of the first directional coupler is connected to the calibration end of the bridge coupler; the through arm of the second directional coupler is connected between the second radio frequency input end and the second input end of the first radio frequency bridge, and the coupled arm of the second directional coupler is connected to the calibration end of the bridge coupler; the first radio frequency input end is used to obtain a first signal, the second radio frequency input end is used to obtain a second signal, the first signal and the second signal are signals obtained by processing the same signal source, and the phase difference between the first signal and the second signal is 90°.

[0005] The solution provided by the embodiment of this application uses a radio frequency bridge to share the power of the first signal and the second signal with a phase difference of 90° to the first radio frequency output end or the second radio frequency output end. When the phase of the first signal leads the phase of the second signal by 90°, the power of the two signals can be shared and output from the first radio frequency output end; when the phase of the second signal leads the phase of the first signal by 90°, the power of the two signals can be shared and output from the second radio frequency output end, realizing power sharing between different channels and improving the coverage ability of the signal without increasing the device power consumption.

[0006] In a possible implementation, the bridge coupler further includes a selection switch and a calibration output terminal; the selection switch includes a fixed terminal, a first selection terminal, and a second selection terminal. The fixed terminal is connected to the calibration terminal of the bridge coupler, the first selection terminal is connected to the coupled arm of the first directional coupler, the first selection terminal is further connected to the coupled arm of the second directional coupler, and the second selection terminal is connected to the calibration output terminal. By configuring the selection switch and the calibration output terminal in the bridge coupler, the bridge coupler can retain the calibration channel between the base station device and the antenna.

[0007] In a possible implementation, the bridge coupler further includes a first switch and a second switch. The first switch is connected between the coupled arm of the first directional coupler and the calibration terminal of the bridge coupler, and the second switch is connected between the coupled arm of the second directional coupler and the calibration terminal of the bridge coupler. By configuring the on / off states of the first switch and the second switch, for example, when the first switch is on and the second switch is off, only the coupled arm of the first directional coupler is connected to the calibration terminal. It is possible to determine whether the cable connection of the first RF input terminal is abnormal by detecting whether a signal is present at the calibration terminal. Similarly, when the first switch is off and the second switch is on, it is possible to determine whether the cable connection of the second RF input terminal is abnormal by detecting whether a signal is present at the calibration terminal.

[0008] In a possible implementation, the bridge coupler further includes a third RF input terminal, a fourth RF input terminal, a second RF bridge, a third RF output terminal, a fourth RF output terminal, a third directional coupler, and a fourth directional coupler. The third RF input terminal is connected to the first input terminal of the second RF bridge, the fourth RF input terminal is connected to the second input terminal of the second RF bridge, the third RF output terminal is connected to the first output terminal of the second RF bridge, and the fourth RF output terminal is connected to the second output terminal of the second RF bridge. The through arm of the third directional coupler is connected between the third RF input terminal and the first input terminal of the second RF bridge, and the coupled arm of the third directional coupler is connected to the calibration terminal of the bridge coupler. The through arm of the fourth directional coupler is connected between the second RF input terminal and the second input terminal of the second RF bridge, and the coupled arm of the fourth directional coupler is connected to the calibration terminal of the bridge coupler. The third RF input terminal is used to obtain a third signal, the fourth RF input terminal is used to obtain a fourth signal. The third signal and the fourth signal are signals obtained by processing the same signal source, and the phase difference between the third signal and the fourth signal is 90°. The bridge coupler can include multiple RF input terminals, and every two of the multiple RF input terminals form a group, so that power sharing can be achieved between the two signals in each group.

[0009] In a possible implementation, the bridge coupler further includes a selection switch and a calibration output terminal; the selection switch includes a fixed terminal, a first selection terminal, and a second selection terminal. The fixed terminal is connected to the calibration terminal of the bridge coupler, the first selection terminal is connected to the coupling arms of the first directional coupler, the coupling arms of the second directional coupler, the coupling arms of the third directional coupler, and the coupling arms of the fourth directional coupler; the second selection terminal is connected to the calibration output terminal of the bridge coupler.

[0010] In a possible implementation, the bridge coupler further includes a first switch, a second switch, a third switch, and a fourth switch; the first switch is connected between the coupling arm of the first directional coupler and the calibration terminal of the bridge coupler; the second switch is connected between the coupling arm of the second directional coupler and the calibration terminal of the bridge coupler; the third switch is connected between the coupling arm of the third directional coupler and the calibration terminal of the bridge coupler; the second switch is connected between the coupling arm of the fourth directional coupler and the calibration terminal of the bridge coupler.

[0011] In a second aspect, an embodiment of the present application further provides a communication system. The communication system includes a bridge coupler provided in any implementation manner of the first aspect and a first radio frequency remote unit; the bridge coupler includes a first radio frequency input terminal, a second radio frequency input terminal, and a calibration terminal; the first radio frequency remote unit includes a first output channel, a second output channel, and a calibration terminal. The first output channel of the first radio frequency remote unit is connected to the first radio frequency input terminal of the bridge coupler, the second output channel of the first radio frequency remote unit is connected to the second radio frequency input terminal of the bridge coupler, and the calibration terminal of the first radio frequency remote unit is connected to the calibration terminal of the bridge coupler; the first radio frequency remote unit is configured to output a first signal through the first output channel of the first radio frequency remote unit and output a second signal through the second output channel of the first radio frequency remote unit. The first signal and the second signal are signals obtained by processing the same signal source, and the phase difference between the first signal and the second signal is 90°.

[0012] In a possible implementation, the communication system further includes a first antenna and a second antenna. The bridge coupler includes a first radio frequency output terminal and a second radio frequency output terminal. The first radio frequency output terminal is connected to the first antenna, and the second radio frequency output terminal is connected to the second antenna. The first antenna and the second antenna may be independent antennas or different antenna transmitting units on the same antenna.

[0013] In a possible implementation, the communication system further includes a second remote radio unit (RRU). The second RRU includes a first output channel and a second output channel. The bridge coupler includes a third RF input terminal and a fourth RF input terminal. The first output channel of the second RRU is connected to the third RF input terminal of the bridge coupler, and the second output channel of the second RRU is connected to the fourth RF input terminal of the bridge coupler. The second RRU is configured to output a third signal through the first output channel of the second RRU and output a fourth signal through the second output channel of the second RRU, and the phase difference between the third signal and the fourth signal is 90°. The bridge coupler can be connected to the same RRU or different RRUs. For example, it can be connected to the first RRU and the second RRU simultaneously. The first RRU and the second RRU can have the same or different standards, and collaborative calibration can be achieved using different RRUs.

[0014] In a third aspect, an embodiment of the present application further provides a heterodyne combiner, which includes: a plurality of input terminals, a filter, a calibration terminal, and a bridge coupler provided in any implementation manner of the first aspect; the first RF input terminal is connected to the first input terminal among the plurality of input terminals of the heterodyne combiner, the second RF input terminal is connected to the second input terminal among the plurality of input terminals of the heterodyne combiner, the first RF output terminal and the second RF output terminal are connected to the input terminal of the filter, and the calibration terminal of the bridge coupler is connected to the calibration terminal of the heterodyne combiner.

[0015] Fourthly, an embodiment of the present application further provides a bridge coupler, which includes a first RF input terminal, a second RF input terminal, a third RF input terminal, a fourth RF input terminal, a first RF bridge, a second RF bridge, a third RF bridge, a fourth RF bridge, a first RF output terminal, a second RF output terminal, a third RF output terminal, a fourth RF output terminal, a first directional coupler, a second directional coupler, a third directional coupler, a fourth directional coupler, a first 45° phase shifter, a second 45° phase shifter, and a calibration terminal; the first RF input terminal is connected to the first input terminal of the first RF bridge, the first output terminal of the first RF bridge is connected to the first input terminal of the third RF bridge through the first 45° phase shifter, and the first output terminal of the third RF bridge is connected to the first RF output terminal; the second RF input terminal is connected to the second input terminal of the first RF bridge, the second output terminal of the first RF bridge is connected to the first input terminal of the fourth RF bridge, and the first output terminal of the fourth RF bridge is connected to the third RF output terminal; the third RF input terminal is connected to the first input terminal of the second RF bridge, the first output terminal of the second RF bridge is connected to the second input terminal of the third RF bridge, and the second output terminal of the third RF bridge is connected to the second RF output terminal; the fourth RF input terminal is connected to the second input terminal of the second RF bridge, the second output terminal of the second RF bridge is connected to the second input terminal of the fourth RF bridge through the second 45° phase shifter, and the second output terminal of the fourth RF bridge is connected to the fourth RF output terminal; the through-arm of the first directional coupler is connected between the first RF input terminal and the first input terminal of the first RF bridge, and the coupled-arm of the first directional coupler is connected to the calibration terminal; the through-arm of the second directional coupler is connected between the second RF input terminal and the second input terminal of the first RF bridge, and the coupled-arm of the second directional coupler is connected to the calibration terminal; the through-arm of the third directional coupler is connected between the third RF input terminal and the first input terminal of the second RF bridge, and the coupled-arm of the third directional coupler is connected to the calibration terminal; the through-arm of the fourth directional coupler is connected between the second RF input terminal and the second input terminal of the second RF bridge, and the coupled-arm of the fourth directional coupler is connected to the calibration terminal.

[0016] The bridge coupler provided by the embodiment of the present application uses multiple RF bridges to form a Butler matrix, which can distribute the power of four signals to one output. The first RF input terminal is used to obtain the first signal, the second RF input terminal is used to obtain the second signal, the third RF input terminal is used to obtain the third signal, and the fourth RF input terminal is used to obtain the fourth signal. The first signal, the second signal, the third signal, and the fourth signal are signals obtained by processing the same signal source. By configuring the phases of the first signal, the second signal, the third signal, and the fourth signal in the digital domain, the power of the four input signals can be distributed to any one of the outputs. The first signal, the second signal, the third signal, and the fourth signal are signals obtained by processing the same signal source. For example, if the phase of the first signal is 0°, the phase of the second signal is -90°, the phase of the third signal is -45°, and the phase of the fourth signal is 135°, the power of the four input signals can be distributed to the first RF output terminal for output, and the output signals of the remaining RF output terminals are 0.

[0017] In a fifth aspect, the embodiment of the present application further provides a communication system, which includes the bridge coupler provided in the fourth aspect and a remote radio unit; the remote radio unit includes a first output channel, a second output channel, a third output channel, a fourth output channel, and a calibration terminal. The first output channel of the remote radio unit is connected to the first RF input terminal of the bridge coupler, the second output channel of the remote radio unit is connected to the second RF input terminal of the bridge coupler, the third output channel of the remote radio unit is connected to the third RF input terminal of the bridge coupler, the fourth output channel of the remote radio unit is connected to the fourth RF input terminal of the bridge coupler, and the calibration terminal of the remote radio unit is connected to the calibration terminal of the bridge coupler. The first output channel is used to output the first signal, the second output channel is used to output the second signal, the third output channel is used to output the third signal, and the fourth output channel is used to output the fourth signal. The first signal, the second signal, the third signal, and the fourth signal are signals obtained by processing the same signal source. The remote radio unit can distribute the power of the four input signals to any one of the outputs by configuring the phases of the first signal, the second signal, the third signal, and the fourth signal in the digital domain. The first signal, the second signal, the third signal, and the fourth signal are signals obtained by processing the same signal source. For example, if the phase of the first signal obtained by the first RF input terminal is 0°, the phase of the second signal obtained by the second RF input terminal is -90°, the phase of the third signal obtained by the third RF input terminal is -45°, and the phase of the fourth signal obtained by the fourth RF input terminal is 135°, the power of the four input signals can be distributed to the first RF output terminal of the bridge coupler for output, and the output signals of the remaining RF output terminals are 0. Description of the Drawings

[0018] Figure 1Schematic diagram of a tunnel communication scenario provided by an embodiment of the present application;

[0019] Figure 2 Schematic diagram of another tunnel communication scenario provided by an embodiment of the present application;

[0020] Figure 3 Schematic diagram of a communication system provided by an embodiment of the present application;

[0021] Figure 4 Schematic diagram of a bridge coupler provided by an embodiment of the present application;

[0022] Figure 5 Schematic diagram of a directional coupler provided by an embodiment of the present application;

[0023] Figure 6 Schematic diagram of a radio frequency bridge provided by an embodiment of the present application;

[0024] Figure 7 Schematic diagram of a communication system provided by an embodiment of the present application;

[0025] Figure 8 Schematic diagram of another communication system provided by an embodiment of the present application;

[0026] Figure 9 Flow schematic diagram of the bridge coupler for cable detection provided by an embodiment of the present application;

[0027] Figure 10 Schematic diagram of another communication system provided by an embodiment of the present application;

[0028] Figure 11 Schematic diagram of another communication system provided by an embodiment of the present application;

[0029] Figure 12 Schematic diagram of another bridge coupler provided by an embodiment of the present application;

[0030] Figure 13 Schematic diagram of another communication system provided by an embodiment of the present application;

[0031] Figure 14 Schematic diagram of another communication system provided by an embodiment of the present application;

[0032] Figure 15 Schematic diagram of another communication system provided by an embodiment of the present application;

[0033] Figure 16 Schematic diagram of another communication system provided by an embodiment of the present application;

[0034] Figure 17Schematic diagram of another bridge coupler provided by an embodiment of the present application;

[0035] Figure 18 Schematic diagram of another bridge coupler provided by an embodiment of the present application;

[0036] Figure 19 Schematic diagram of yet another bridge coupler provided by an embodiment of the present application;

[0037] Figure 20 Schematic diagram of another communication system provided by an embodiment of the present application;

[0038] Figure 21 Schematic diagram of a heterodyne combiner provided by an embodiment of the present application. Detailed implementation manners

[0039] The fabrication and use of each embodiment will be discussed in detail below. However, it should be understood that many applicable inventive concepts provided by the present application can be implemented in a variety of specific environments. The specific embodiments discussed merely illustrate specific ways of implementing and using this specification and this technology, and do not limit the scope of the present application. Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those of ordinary skill in the art.

[0040] Each circuit or other component may be described as or referred to as "configured to" or "for" performing one or more tasks. In this case, "configured to" or "for" is used to imply structure by indicating that the circuit / component includes a structure (such as circuitry) that performs one or more tasks during operation. Thus, even when the specified circuit / component is currently inoperable (e.g., not turned on), the circuit / component can still be referred to as being configured to perform the task. A circuit / component used in conjunction with the phrase "configured to" includes hardware, such as circuitry that performs the operation, etc.

[0041] The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application. In the present application, "at least one" means one or more, and "a plurality" may mean two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone, where A and B may be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c may represent: a, b, c, a and b, a and c, b and c, a, b, and c; where a, b, and c may be single or multiple.

[0042] Embodiments of the present application use terms such as "first" and "second" to distinguish objects with similar names, functions, or roles. Those skilled in the art can understand that terms such as "first" and "second" do not limit the quantity and execution order. The term "coupled" is used to represent an electrical connection, including directly connected through a wire or connection terminal or indirectly connected through other devices. Therefore, "coupled" should be regarded as a generalized electronic communication connection.

[0043] Power sharing technology can improve the utilization rate of module power by flexibly allocating power without increasing the total output power of the module, thereby improving the coverage level without increasing the power consumption of the device.

[0044] For example, a possible power sharing method is to share power among communication systems of different systems in the same power amplifier. For example, some base stations are shared by 4G and 5G. 5G and 4G signals can share the same power amplifier. When only 4G signals are transmitted, the power of the 5G signal can be allocated to the transmission of 4G signals to increase the power of 4G signals; when only 5G signals are transmitted, the power of the 4G signal can be allocated to the transmission of 5G signals to increase the power of 5G signals.

[0045] Another possible power sharing method is to flexibly share power among different carriers sharing the same power amplifier. For example, a 100M spectrum is divided into 5 carriers, and the spectrum width of each carrier is 20M. If the power of each carrier is 20W, in the case where the 5 carriers do not transmit simultaneously, the power of the untransmitted carriers can be allocated to the power of the transmitted carriers. For example, if only 1 carrier is transmitting, then the power of the remaining 4 carriers can be allocated to the transmitting carrier to achieve power sharing among different carriers.

[0046] The above power sharing methods can only support sharing among signals sharing the same power amplifier and cannot achieve sharing among different power amplifiers. For example, in application scenarios such as railway or subway tunnels, base station equipment is usually built along the railway tracks. The base station equipment can be provided with two power amplifiers, one of which is used to amplify the signals transmitted in the direction of the tunnel entrance, and the other is used to amplify the signals transmitted in the direction of the tunnel exit. As Figure 1 shown, the two output channels of the base station are respectively connected to antenna A and antenna B, and antenna A and antenna B can respectively transmit signals in the direction of the tunnel entrance and in the direction of the tunnel exit.

[0047] In scenarios such as tunnels, users are basically concentrated in the train carriages. As the train moves, at a certain moment, users are only on one side of the base station. On the basis of Figure 1 and in combination with Figure 2, The train moves from left to right along the direction shown in the figure. When the train is on the right side of antenna A and on the left side of antenna B, the user can receive the signals transmitted by both antenna A and antenna B simultaneously; when the train is on the left side of antenna A or on the right side of antenna B, the user can only receive the signal transmitted by antenna A or the signal transmitted by antenna B. Since the antennas on both sides of the base station are connected to different power amplifier channels of the base station equipment, it is impossible to share the power on one side to the other side, which will cause power waste.

[0048] To improve the above problems, the embodiments of the present application provide a solution that can use a bridge coupler to distribute the power of different power amplifier channels to the same output port. For example, the signal power of the above two channels can be distributed to antenna A or antenna B. Combining Figure 2 with the scenario shown in the figure, when the train is on the left side of antenna A, the power of the two channels can be distributed to antenna A to increase the power of the signal transmitted by antenna A; when the train is on the right side of antenna B, the power of the two channels can be distributed to antenna B to increase the power of the signal transmitted by antenna B, realizing power sharing and improving the coverage ability without increasing the overall power consumption.

[0049] The solution provided by the embodiments of the present application can be applied to communication systems, such as: Global System for Mobile Communications (GSM) system, Code Division Multiple Access (CDMA) system, Wideband Code Division Multiple Access (WCDMA) system, General Packet Radio Service (GPRS), Long Term Evolution (LTE) system, LTE Frequency Division Duplex (FDD) system, LTE Time Division Duplex (TDD), Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WIMAX) communication system, 5th generation (5G) system or New Radio (NR), etc.

[0050] Refer to Figure 3 , Figure 3FIG. shows a schematic diagram of a communication system provided by an embodiment of the present application, including a baseband processing unit (BBU) 100, a radio remote unit (RRU) 200, and an antenna. The BBU 100 is used for processing baseband signals, the RRU 200 is used to convert baseband data into radio frequency signals, the RRU 200 can be connected to the antenna, and the antenna can radiate the radio frequency signals into space for communication connection with end users. Usually, the BBU can be connected to multiple RRUs, and the RRU can include multiple output channels, such as two-channel, four-channel, etc. Each output channel integrates a power amplifier, which can amplify and output the signals. The RRU can also include a calibration channel. The calibration channel of the RRU can be connected to the antenna, and the signal of the calibration channel can be used to adjust the signal phase of the RRU transmitted to the antenna.

[0051] Figure 3 In the shown communication system, the signals of different output channels of the RRU 200 are transmitted through different antennas, and the signal powers between different power amplifiers cannot be shared, resulting in power waste. An embodiment of the present application provides a bridge coupler, which can be set between the RRU and the antenna to improve the problem that the power cannot be shared between different channels or power amplifiers.

[0052] Refer to Figure 4 , Figure 4 FIG. shows a schematic diagram of a bridge coupler 300 provided by an embodiment of the present application. The bridge coupler 300 includes a radio frequency bridge 31, a first radio frequency input end 32_1, a second radio frequency input end 32_2, a first radio frequency output end 33_1, a second radio frequency output end 33_2, a first directional coupler 34_1, a second directional coupler 34_2, and a calibration end 35.

[0053] The radio frequency bridge 31 includes a first input end P1, a second input end P2, a first output end Q1, and a second output end Q2. The first radio frequency input end 32_1 is connected to the first input end P1 of the radio frequency bridge 31, the second radio frequency input end 32_2 is connected to the second input end P2 of the radio frequency bridge 31, the first radio frequency output end 33_1 is connected to the first output end Q1 of the radio frequency bridge 31, and the second radio frequency output end 33_2 is connected to the second output end Q2 of the radio frequency bridge 31.

[0054] A directional coupler is a four-port device. Figure 5A schematic diagram of a directional coupler is shown. The directional coupler includes a through arm and a coupled arm. The coupled arm includes a coupled end a and an isolated end b. The through arm includes a through input end c and a through output end d. A portion of the signal power on the through arm is coupled to the coupled arm through a coupling mechanism (such as a slot, a hole, a coupling line segment, etc.) between the through arm and the coupled arm, and is output through the coupled end a. The coupled end a and the isolated end b are reciprocal. When the signal transmission direction on the through arm is from the through input end c to the through output end d, the coupled end a serves as the output end of the coupled signal; conversely, when the signal transmission direction on the through arm is from the through output end d to the through input end c, the isolated end b serves as the output end of the coupled signal.

[0055] Please continue to combine with Figure 4 , the through arm of the first directional coupler 34_1 is connected between the first RF input end 32_1 and the first input end P1 of the RF bridge 31, and the coupled arm of the first directional coupler 34_1 is connected to the calibration end 35 of the bridge coupler 300. The through arm of the second directional coupler 34_2 is connected between the second RF input end 32_2 and the second input end P2 of the RF bridge 31, and the coupled arm of the second directional coupler 34_2 is connected to the calibration end 35 of the bridge coupler 300.

[0056] The RF bridge 31 is a 3dB bridge, which is a device with two-channel input and two-channel output, used to implement a cross-network connection, also known as an orthogonal RF bridge or a 90° RF bridge. The transmission matrix of the RF bridge 31 is as follows:

[0057]

[0058] Combined with Figure 6 , for example, if the signal at the first input end P1 of the RF bridge 31 is A1 and the signal at the second input end P2 is A2, the signal at the first input end P1 can be output through the first output end Q1 as A1. When the signal at the first input end P1 is output through the second output end Q2, it will be phase-shifted by 90°, which is A1∠90° (indicating that the phase of the signal A1 is 90°), or can be denoted as A1j. Similarly, the signal at the second input end P2 can be output through the second output end Q2 as A2. When the signal at the second input end P2 is output through the first output end Q1, it will be phase-shifted by 90°, which is A2∠90°, or can be denoted as A2j.

[0059] If the signal A1 and the signal A2 include the same components and the phase difference between the signal A1 and the signal A2 is 90°, then the RF bridge 31 can distribute the signal power to one of the output channels.

[0060] For example, if signal A2 is A1∠90°, then at the first output terminal Q1 of the RF bridge 31, A1∠180° + A1 can be output, and at the second output terminal Q2 of the RF bridge 31, A1∠90° + A1∠90° can be output. Since A1∠180° and A1 have the same amplitude and opposite phases, they completely cancel each other out, so the output at the first output terminal Q1 of the RF bridge 31 is 0; since A1∠90° and A1∠90° have the same amplitude and the same phase, they can be superimposed, so the signal output at the second output terminal Q2 of the RF bridge 31 is 2A1.

[0061] Alternatively, if signal A1 is A2∠90°, then at the first output terminal Q1 of the RF bridge 31, A2∠90° + A2∠90° can be output, and at the second output terminal Q2 of the RF bridge 31, A2∠180° + A2 can be output. Since A2∠180° and A2 have the same amplitude and opposite phases, they completely cancel each other out, so the output at the second output terminal Q2 of the RF bridge 31 is 0; since A2∠90° and A2∠90° have the same amplitude and the same phase, they can be superimposed, so the signal output at the first output terminal Q1 of the RF bridge 31 is 2A2.

[0062] Based on this characteristic of the RF bridge, in the embodiment of the present application, the first input terminal P1 of the RF bridge 31 is connected to the first RF input terminal 32_1 of the bridge coupler 300, the first output terminal Q1 of the RF bridge 31 is connected to the first RF output terminal 33_1 of the bridge coupler 300, the second input terminal P2 of the RF bridge 31 is connected to the second RF input terminal 32_2 of the bridge coupler 300, and the second output terminal Q2 of the RF bridge 31 is connected to the second RF output terminal 33_2 of the bridge coupler 300. The first RF input terminal 32_1 of the bridge coupler 300 is used to obtain a first signal, the second RF input terminal 32_2 is used to obtain a second signal. The first signal and the second signal are signals obtained by processing the same signal source, and the phase difference between the first signal and the second signal is 90°. In this way, through the RF bridge 31, the power of the first signal and the second signal can be distributed to the first RF output terminal 33_1 or the second RF output terminal 33_2 for output.

[0063] For example, in one example, the first signal and the second signal include the same signal component A, where the first signal is A and the second signal is Aj, that is, the phase of the second signal leads the first signal by 90°. The first signal is transmitted to the first input terminal P1 of the radio frequency bridge 31, and the second signal is transmitted to the second output terminal Q2 of the radio frequency bridge 31. Combining the transmission matrix of the radio frequency bridge 31 above, the signal output at the first output terminal Q1 of the radio frequency bridge 31 is A + A∠180°, and the signal output at the second output terminal Q2 of the radio frequency bridge 31 is Aj + Aj. That is, the signal output at the first radio frequency output terminal 33_1 of the bridge coupler 300 is 0, and the signal output at the second radio frequency output terminal 33_2 of the bridge coupler 300 is 2A, thus realizing the power distribution to the second radio frequency output terminal 33_2, and realizing the power sharing between different power amplifier channels.

[0064] Similarly, when the first signal input to the first radio frequency input terminal 32_1 of the bridge coupler 300 is Aj and the second signal input to the second radio frequency input terminal 32_2 is A, the phase of the first signal leads the phase of the second signal by 90°. The signal output at the first radio frequency output terminal 33_1 of the bridge coupler 300 is 2A, and the signal output at the second radio frequency output terminal 33_2 of the bridge coupler 300 is 0, realizing the power sharing of the two input signals to the first radio frequency output terminal 33_1, and realizing the power sharing between different power amplifier channels.

[0065] The bridge coupler 300 can perform power distribution on the input first signal and second signal, and distribute the power of the two signals to one output terminal, but it is necessary to ensure that the first signal and the second signal are signals obtained by processing the same signal source, and the phase difference between the first signal and the second signal is 90°, for example, the first signal can lead the second signal by 90°, or the second signal can lead the first signal by 90°.

[0066] However, since the bridge coupler 300 is connected to the RRU through radio frequency connection lines, etc., the radio frequency connection lines themselves will cause phase shift of the signal. Therefore, if the phase difference between the two signals output by the RRU is 90°, but when transmitted to the first radio frequency input terminal and the second radio frequency input terminal of the bridge coupler 300, the phase difference of these two signals may shift and does not meet the requirement of a 90° phase difference.

[0067] The bridge coupler 300 provided in the embodiment of the present application includes a correction terminal. The bridge coupler 300 can couple a part of the first signal and the second signal and output it through the correction terminal. For example, the RRU can perform phase compensation on the signal output from the RRU to the bridge coupler 300 according to the signal at the correction terminal of the bridge coupler 300 to ensure that the phase difference between the first signal and the second signal is 90°.

[0068] For example, refer to Figure 7 ,Figure 7 The figure shows a schematic diagram of a communication system provided by an embodiment of the present application. The communication system includes a BBU 100, an RRU 200, a bridge coupler 300, and antennas A and B. The bridge coupler 300 includes a first RF input terminal 32_1, a second RF input terminal 32_2, a first RF output terminal 33_1, a second RF output terminal 33_2, and a calibration terminal 35. The first RF input terminal 32_1 is connected to the first output channel of the RRU 200, the second RF input terminal 32_2 is connected to the second output channel of the RRU 200, the first RF output terminal 33_1 is connected to the antenna A, the second RF output terminal 33_2 is connected to the antenna B, and the calibration terminal 35 of the bridge coupler 300 is connected to the calibration channel of the RRU 200. The antennas A and B can be different antennas or different antenna units in the same sector antenna.

[0069] The first output channel of the RRU 200 is used to output a first signal to the first RF input terminal 34_1 of the bridge coupler 300, and the second output channel of the RRU 200 is used to output a second signal to the second RF input terminal 34_2 of the bridge coupler 300. In the foregoing example, it is mentioned that the first signal and the second signal are signals obtained by processing the same signal source, and the phase difference between the first signal and the second signal is 90°. For example, the first signal and the second signal can be the same signal with a 90° phase difference. For example, the first signal is A and the second signal is A∠90°, or the second signal is A and the first signal is A∠90°. The first signal and the second signal can also be signals with the same components but different weights for each component. For example, two signal sources respectively generate signal A and signal B, and the RRU performs weighted processing on signal A and signal B to output the first signal and the second signal. For example, the first signal can be A+xB, the second signal can be A+yB, and the phase difference between the first signal and the second signal is 90°, where x and y represent the weights of the signals.

[0070] The bridge coupler 300 can output a calibration signal through the calibration terminal 35, and the RRU 200 can compensate for the phases of the output first signal and second signal according to the calibration signal to ensure that the phase difference between the first signal at the first RF input terminal 34_1 and the second signal at the second RF input terminal 34_2 of the bridge coupler 300 is 90°.

[0071] Among them, the bridge coupler 300 includes a first directional coupler 34_1 and a second directional coupler 34_2. The first directional coupler 34_1 can couple the signal input from the first RF input end 32_1 to the calibration end 35 of the bridge coupler 300 for output. The second directional coupler 34_2 can couple the signal input from the second RF input end 32_2 to the calibration end 35 of the bridge coupler 300 for output. The calibration end 35 of the bridge coupler 300 is connected to the calibration channel of the RRU 200. The RRU 200 can determine the phase difference between the signals of the first RF input end 32_1 and the second RF input end 32_2 according to the signal output from the calibration end 35 of the bridge coupler 300, and compensate the phases of the first signal and the second signal in the digital domain to ensure that the phase difference between the first signal and the second signal input to the bridge coupler 300 is 90°.

[0072] In some examples, the calibration end of the bridge coupler supports OOK signals and supports direct current power supply to the directional coupler.

[0073] It can be seen from the above that by setting the first directional coupler 34_1 and the second directional coupler 34_2, a part of the first signal input from the first RF input end 32_1 can be coupled to the calibration end 35, and a part of the second signal input from the second RF input end 32_2 can be coupled to the calibration end 35. Based on this characteristic, the cable connection conditions of the first RF input end 32_1 and the second RF input end 32_2 can also be detected by setting switches and switching the conduction states.

[0074] In a possible implementation, referring to Figure 8 , the bridge coupler 300 further includes a first switch K1 and a second switch K2. The first switch K1 is disposed between the coupling arm of the first directional coupler 34_1 and the calibration end 35 of the bridge coupler 300. The second switch K2 is disposed between the coupling arm of the second directional coupler 34_2 and the calibration end 35 of the bridge coupler 300.

[0075] Figure 9The figure shows a schematic flowchart of cable connection detection of the bridge coupler provided by the embodiment of the present application. Taking the cable connection of the first radio frequency input end 32_1 as an example, the first output channel of the RRU 200 transmits a calibration signal sequence. The bridge coupler 300 controls the first switch K1 to conduct and the second switch K2 to disconnect, that is, disconnects the coupling arm of the second directional coupler 34_2 from the calibration end 35, and only the coupling arm of the first directional coupler 34_1 conducts with the calibration end 35. If the calibration channel of the RRU 200 cannot detect a signal at the calibration end 35 of the bridge coupler 300 in this case, it indicates that there may be an abnormality in the cable connection of the first radio frequency input end 32_1 of the bridge coupler 300; if the calibration channel of the RRU 200 detects a signal, it indicates that the cable connection of the first radio frequency input end 32_1 of the bridge coupler 300 is fault-free.

[0076] Conversely, if the second output channel of the RRU 200 transmits a calibration signal sequence, the first switch K1 of the bridge coupler 300 is disconnected and the second switch K2 is conducted. The coupling arm of the first directional coupler 34_1 is disconnected from the calibration end 35, and only the coupling arm of the second directional coupler 34_2 conducts with the calibration end 35. If the calibration channel of the RRU 200 cannot detect a signal at the calibration end 35 of the bridge coupler 300 in this case, it indicates that there may be an abnormality in the cable connection of the second radio frequency input end 32_2; therefore, by combining the switching of the conduction states of the first switch K1 and the second switch K2, the cable connection detection of the first radio frequency input end 32_1 and the second radio frequency input end 32_2 can be realized.

[0077] A calibration loop is usually set between the RRU and the antenna. Usually, the RRU is only provided with one calibration channel. The calibration end of the bridge coupler provided by the embodiment of the present application is connected to the calibration channel of the RRU, occupying the calibration channel of the RRU. In order to ensure the normal operation of the calibration loop between the RRU and the antenna, in a possible implementation, refer to Figure 10 , the bridge coupler 300 further includes a calibration output end 36 and a selection switch S. The selection switch S includes a first selection end S1, a second selection end S2, and a fixed end S3. The fixed end S3 of the selection switch S is connected to the calibration end 35 of the bridge coupler 300. The first selection end S1 of the selection switch S is connected to the coupling arm of the first directional coupler 34_1, and the first selection end S1 is also connected to the coupling arm of the second directional coupler 34_2; the second selection end S2 of the selection switch S is connected to the calibration output end 36.

[0078] When the fixed terminal S3 of the selection switch S is conducted with the first selection terminal S1 of the selection switch S, the coupled arms of the first directional coupler 34_1 and the coupled arms of the second directional coupler 34_2 are connected to the calibration channel of the RRU 200 through the calibration terminal 35 of the bridge coupler 300. When the fixed terminal S3 of the selection switch S is conducted with the second selection terminal S2 of the selection switch S, the calibration terminal 35 of the bridge coupler 300 is connected to the calibration output terminal 36 of the bridge coupler 300, where the calibration output terminal 36 can be connected to an antenna. In this way, it is equivalent that the calibration channel of the RRU 200 is connected to the antenna through the calibration terminal 35 and the calibration output terminal 36 of the bridge coupler 300, which can ensure the normal operation of the calibration loop between the RRU 200 and the antenna.

[0079] Exemplarily, in combination with Figure 11 , in this case, a first switch K1 can also be set between the coupled arm of the first directional coupler 34_1 and the first selection terminal S1 of the selection switch S, and a second switch K2 can be set between the coupled arm of the second directional coupler 34_2 and the first selection terminal S1 of the selection switch S. By using the conduction state switching of the first switch K1, the second switch K2 and the selection switch S, the cable connection detection of the first RF input terminal 32_1 and the second RF input terminal 32_2 of the bridge coupler 300 can be realized. The specific principle has been introduced in the foregoing example and will not be elaborated here.

[0080] The bridge coupler 300 provided in the foregoing example includes two inputs, two outputs and a RF bridge, and can realize sharing the power of two signals with a phase difference of 90° to one output. The embodiment of the present application also provides another bridge coupler, which includes multiple inputs and multiple outputs, and can group every two of the multiple inputs to realize signal power sharing between a group of signals.

[0081] For example, referring to Figure 12 , the embodiment of the present application provides another bridge coupler 400. The bridge coupler 400 includes a first RF bridge 41_1, a second RF bridge 41_2, a first RF input terminal 42_1, a second RF input terminal 42_2, a third RF input terminal 42_3, a fourth RF input terminal 42_4, a first RF output terminal 43_1, a second RF output terminal 43_2, a third RF output terminal 43_3, a fourth RF output terminal 43_4 and a calibration terminal 45.

[0082] The first RF bridge 41_1 and the second RF bridge 41_2 can be of the same frequency or different frequencies. The first RF input terminal 42_1 is connected to the first input terminal P1 of the first RF bridge 41_1, the second RF input terminal 42_2 is connected to the second input terminal P2 of the first RF bridge 41_1, the first RF output terminal 43_1 is connected to the first output terminal Q1 of the first RF bridge 41_1, and the second RF output terminal 43_2 is connected to the second output terminal Q2 of the first RF bridge 41_1.

[0083] The third RF input terminal 42_3 is connected to the first input terminal P1 of the second RF bridge 41_2, the fourth RF input terminal 42_4 is connected to the second input terminal P2 of the second RF bridge 41_2, the third RF output terminal 43_3 is connected to the first output terminal Q1 of the second RF bridge 41_2, and the fourth RF output terminal 43_4 is connected to the second output terminal Q2 of the second RF bridge 41_2.

[0084] The first RF input terminal 42_1 is used to obtain a first signal, the second RF input terminal 42_2 is used to obtain a second signal. The first signal and the second signal are signals obtained by processing the same signal source, and the phase difference between the first signal and the second signal is 90°. Based on the first RF bridge 41_1, the signals of the first RF input terminal 42_1 and the second RF input terminal 42_2 can share the power to the first RF output terminal 43_1 or the second RF output terminal 43_2.

[0085] The third RF input terminal 42_3 is used to obtain a third signal, the fourth RF input terminal 42_4 is used to obtain a fourth signal. The third signal and the fourth signal are signals obtained by processing the same signal source, and the phase difference between the third signal and the fourth signal is 90°. Based on the second RF bridge 41_2, the signals of the third RF input terminal 42_3 and the fourth RF input signal terminal can share the power to the third RF output terminal 43_3 or the fourth RF output terminal 43_4.

[0086] Corresponding to the multi-channel bridge coupler, the RRU can also have multiple output channels. For example, refer to Figure 13, the RRU 200 includes a first output channel, a second output channel, a third output channel, a fourth output channel, and a calibration channel. The first output channel is used to transmit a first signal to the first RF input terminal 44_1 of the bridge coupler 400. The second output channel is used to transmit a second signal to the second RF input terminal 44_2 of the bridge coupler 400. The third output channel is used to transmit a third signal to the third RF input terminal 44_3 of the bridge coupler 400. The fourth output channel is used to transmit a fourth signal to the fourth RF input terminal 44_4 of the bridge coupler 400. The calibration terminal 45 of the bridge coupler 400 is connected to the calibration channel of the RRU 200. The RRU 200 can compensate the phases of the first signal and the second signal according to the signal output from the calibration terminal 45 of the bridge coupler 400 to ensure that the phase difference between the first signal and the second signal is 90°; or compensate the phases of the third signal and the fourth signal to ensure that the phase difference between the third signal and the fourth signal is 90°.

[0087] Exemplarily, the bridge coupler 400 further includes a first directional coupler 44_1, a second directional coupler 44_2, a third directional coupler 44_3, and a fourth directional coupler 44_4. The through-arm of the first directional coupler 44_1 is connected between the first RF input terminal 42_1 and the first input terminal P1 of the first RF bridge 41_1. The coupled-arm of the first directional coupler 44_1 is connected to the calibration terminal 45 of the bridge coupler 400. The through-arm of the second directional coupler 44_2 is connected between the second RF input terminal 42_2 and the second input terminal P2 of the first RF bridge 41_1. The coupled-arm of the second directional coupler 44_2 is connected to the calibration terminal 45 of the bridge coupler 400.

[0088] The first directional coupler 44_1 can couple the signal input from the first RF input terminal 42_1 to the calibration terminal 45 of the bridge coupler 400 for output. The second directional coupler 44_2 can couple the signal input from the second RF input terminal 42_2 to the calibration terminal 45 of the bridge coupler 400 for output. For example, the calibration terminal 45 of the bridge coupler 400 is connected to the calibration channel of the RRU 200. The RRU 200 can determine the phase difference between the signals of the first RF input terminal 42_1 and the second RF input terminal 42_2 according to the signal output from the calibration terminal 45 of the bridge coupler 400, and compensate the phases of the first signal and the second signal in the digital domain to ensure that the phase difference between the first signal and the second signal input to the bridge coupler 400 is 90°.

[0089] The through arm of the third directional coupler 44_3 is connected between the third RF input terminal 42_3 and the first input terminal P1 of the second RF bridge 41_2, and the coupled arm of the third directional coupler 44_3 is connected to the calibration terminal 45 of the bridge coupler 400; the through arm of the fourth directional coupler 44_4 is connected between the second RF input terminal 42_2 and the second input terminal P2 of the second RF bridge 41_2, and the coupled arm of the fourth directional coupler 44_4 is connected to the calibration terminal 45 of the bridge coupler 400.

[0090] The third directional coupler 44_3 can couple the signal input from the third RF input terminal 42_3 to the calibration terminal 45 of the bridge coupler 400 for output, and the fourth directional coupler 44_4 can couple the signal input from the fourth RF input terminal 42_4 to the calibration terminal 45 of the bridge coupler 400 for output. The RRU 200 can determine the phase difference between the signals of the third RF input terminal 42_3 and the fourth RF input terminal 42_4 according to the signal output from the calibration terminal 45 of the bridge coupler 400, and compensate the phases of the third signal and the fourth signal in the digital domain to ensure that the phase difference between the third signal and the fourth signal input to the bridge coupler 400 is 90°.

[0091] In a possible implementation, a switch may be provided between the directional coupler and the calibration terminal 45 of the bridge coupler 400. For example, refer to Figure 14 , the bridge coupler 400 includes a first switch K1, a second switch K2, a third switch K3, and a fourth switch K4. The first switch K1 is disposed between the coupled arm of the first directional coupler 44_1 and the calibration terminal 45 of the bridge coupler 400, and can be used to control the conduction state between the coupled arm of the first directional coupler 44_1 and the calibration terminal 45 of the bridge coupler 400; the second switch K2 is disposed between the coupled arm of the second directional coupler 44_2 and the calibration terminal 45 of the bridge coupler 400, and can be used to control the conduction state between the coupled arm of the second directional coupler 44_2 and the calibration terminal 45 of the bridge coupler 400; the third switch K3 is disposed between the coupled arm of the third directional coupler 44_3 and the calibration terminal 45 of the bridge coupler 400, and can be used to control the conduction state between the coupled arm of the third directional coupler 44_3 and the calibration terminal 45 of the bridge coupler 400; the fourth switch K4 is disposed between the coupled arm of the fourth directional coupler 44_4 and the calibration terminal 45 of the bridge coupler 400, and can be used to control the conduction state between the coupled arm of the fourth directional coupler 44_4 and the calibration terminal 45 of the bridge coupler 400.

[0092] By switching the conduction states of the first switch K1, the second switch K2, the third switch K3, and the fourth switch K4, it is possible to determine whether there is a fault in the cable connection of the first radio frequency input terminal 42_1 to the fourth radio frequency input terminal 42_4 of the bridge coupler 400 by checking whether a signal is detected at the calibration terminal 45 of the bridge coupler 400. For example, when the first switch K1, the second switch K2, and the third switch K3 are switched to the off state and the fourth switch K4 is switched to the on state, if no signal is detected at the calibration terminal 45 of the bridge coupler 400, it indicates that the cable connected to the fourth radio frequency input terminal 42_4 of the bridge coupler 400 may be faulty.

[0093] In another possible implementation, refer to Figure 15 , the bridge coupler 400 further includes a calibration output terminal 46 and a selection switch S. The selection switch S includes a fixed terminal S3, a first selection terminal S1, and a second selection terminal S2. The fixed terminal S3 of the selection switch S is connected to the calibration terminal 45 of the bridge coupler 400. The first selection terminal S1 of the selection switch S is connected to the coupled arms of the first directional coupler 44_1, the second directional coupler 44_2, the third directional coupler 44_3, and the fourth directional coupler 44_4. The second selection terminal S2 of the selection switch S is connected to the calibration output terminal 46.

[0094] When the fixed terminal S3 of the selection switch S is conducting with the first selection terminal S1 of the selection switch S, the coupled arms of the first directional coupler 44_1, the second directional coupler 44_2, the third directional coupler 44_3, and the fourth directional coupler 44_4 are connected to the calibration channel of the RRU 200 through the calibration terminal 45 of the bridge coupler 400.

[0095] When the fixed terminal S3 of the selection switch S is conducting with the second selection terminal S2 of the selection switch S, the calibration terminal 45 of the bridge coupler 400 is connected to the calibration output terminal 46 of the bridge coupler 400. The calibration output terminal 46 can be connected to an antenna. In this way, it is equivalent to connecting the calibration channel of the RRU 200 to the antenna through the calibration terminal 45 and the calibration output terminal 46 of the bridge coupler 400, which can ensure the normal operation of the calibration loop between the RRU 200 and the antenna.

[0096] In another possible implementation, in combination with Figure 16, a first switch K1 may also be provided between the coupling arm of the first directional coupler 44_1 and the first selection end S1 of the selection switch S, a second switch K2 may be provided between the coupling arm of the second directional coupler 44_2 and the first selection end S1 of the selection switch S, a third switch K3 may be provided between the coupling arm of the third directional coupler 44_3 and the first selection end S1 of the selection switch S, and a fourth switch K4 may be provided between the coupling arm of the fourth directional coupler 44_4 and the first selection end S1 of the selection switch S. By switching the conduction states of the first switch K1, the second switch K2, the third switch K3, the fourth switch K4, and the selection switch S, the cable connection detection of the first RF input end 42_1, the second RF input end 42_2, the third RF input end 42_3, and the fourth RF output end 43_4 of the bridge coupler 400 can be realized. The specific principle has been introduced in the foregoing examples and will not be elaborated here.

[0097] The foregoing examples illustrate by taking the bridge coupler including one and two RF bridges respectively. The bridge coupler may also include more RF bridges, so that the bridge coupler may have more RF input ends and RF output ends. For example, the bridge coupler includes n RF bridges. For example, in combination with Figure 17 , the bridge coupler 400 may include n RF bridges such as RF bridge 41_1, RF bridge 41_2... RF bridge 41_n. The bridge coupler may correspondingly be provided with 2n RF input ends, 2n RF output ends, and calibration ends.

[0098] In the foregoing example, the bridge coupler is connected to one RRU. In another example, the embodiment of the present application further provides another communication system. The bridge coupler may be connected to multiple RRUs, and the systems of the multiple RRUs may be the same or different. For example, one of the RRUs is of the FDD system, and the other RRU is of the TDD system.

[0099] Refer to Figure 18 , Figure 18 shows a schematic diagram of another communication system provided by the embodiment of the present application, including a BBU 100, an RRU 200_1, an RRU 200_2, and a bridge coupler 500. Among them, the RRU 200_1 may be an 8-output-channel TDD8T RRU, and the RRU 200_2 may be a 4-output-channel FDD 4T RRU. Correspondingly, the bridge coupler 500 may include 12 input channels and 12 output channels. The 8 output channels of the RRU 200_1 may be connected to the first 8 RF input ends of the bridge coupler 500, and the 4 output channels of the RRU 200_2 may be connected to the last 4 input channels of the bridge coupler 500.

[0100] In a possible implementation, RRU 200_2 does not have a calibration channel, while RRU 200_1 has a calibration channel. In this case, the calibration terminal 55 of the bridge coupler 500 can be connected to the calibration channel of RRU 200_1 to output the calibration signal to RRU 200_1. RRU 200_1 can then send the calibration signal to BBU 100, and BBU 100 calculates the phase of the signal and compensates the phase of the signal output to the bridge coupler 500 to achieve collaborative calibration among multiple devices.

[0101] In the above example, the bridge coupler can be connected to multiple input signals, but power sharing can only be achieved between two input signals. Another bridge coupler provided in the embodiments of the present application can share the power of 4 (or more) input signals to any one output channel.

[0102] For example, refer to Figure 19 and Figure 20 , Figure 19 which is a schematic diagram of another bridge coupler 600 provided in the embodiments of the present application. Figure 20 which is a schematic diagram of another communication system provided in the embodiments of the present application. The bridge coupler 600 includes four RF input terminals, four RF output terminals, four RF bridges, and two 45° phase shifters.

[0103] The first RF input terminal 62_1 is connected to the first input terminal P1 of the first RF bridge 61_1. The first output terminal Q1 of the first RF bridge 61_1 is connected to the first input terminal P1 of the third RF bridge 61_3 through the first 45° phase shifter 67_1. The first output terminal Q1 of the third RF bridge 61_3 is connected to the first RF output terminal 63_1 of the bridge coupler 600.

[0104] The second RF input terminal 62_2 is connected to the second input terminal P2 of the first RF bridge 61_1. The second output terminal Q2 of the first RF bridge 61_1 is connected to the first input terminal P1 of the fourth RF bridge 61_4. The first output terminal Q1 of the fourth RF bridge 61_4 is connected to the third RF output terminal 63_3 of the bridge coupler 600.

[0105] The third RF input terminal 62_3 is connected to the first input terminal P1 of the second RF bridge 61_2. The first output terminal Q1 of the second RF bridge 61_2 is connected to the second input terminal P2 of the third RF bridge 61_3. The second output terminal Q2 of the third RF bridge 61_3 is connected to the second RF output terminal 63_2 of the bridge coupler 600.

[0106] The fourth RF input terminal 62_4 is connected to the second input terminal P2 of the second RF bridge 61_2. The second output terminal Q2 of the second RF bridge 61_2 is connected to the second input terminal P2 of the fourth RF bridge 61_4 through the second 45° phase shifter 67_2. The second output terminal Q2 of the fourth RF bridge 61_4 is connected to the fourth RF output terminal 63_4 of the bridge coupler 600.

[0107] Four RF bridges and two 45° phase shifters form a Butler matrix. The first RF input terminal 62_1 is used to obtain the first signal, the second RF input terminal 62_2 is used to obtain the second signal, the third RF input terminal 62_3 is used to obtain the third signal, and the fourth RF input terminal 62_4 is used to obtain the fourth signal. The first signal, the second signal, the third signal, and the fourth signal are signals obtained by processing the same signal source. By configuring the phases of the first signal, the second signal, the third signal, and the fourth signal in the digital domain, the power of the four input signals can be distributed to any one of the outputs.

[0108] For example, the first signal, the second signal, the third signal, and the fourth signal are signals obtained by processing the same signal source. For example, the phase of the first signal is 0°, the phase of the second signal is -90°, the phase of the third signal is -45°, and the phase of the fourth signal is 135°. Then, the power of the four input signals can be distributed to the first RF output terminal 63_1 for output, and the output signals of the remaining RF output terminals are 0.

[0109] Based on the same principle, by configuring the weights of the first signal, the second signal, the third signal, and the fourth signal, the power of the four signals can also be superimposed on any one or more RF output ports.

[0110] Similar to the foregoing example, the bridge coupler 600 also includes a plurality of directional couplers for coupling a part of the signal input at the RF signal input end and outputting it through the calibration end 65. For example, the bridge coupler 600 includes a first directional coupler 64_1, a second directional coupler 64_2, a third directional coupler 64_3, and a fourth directional coupler 64_4. The through-arm of the first directional coupler 64_1 is connected between the first RF input end 62_1 and the first input end P1 of the first RF bridge 61_1, and the coupled-arm of the first directional coupler 64_1 is connected to the calibration end 65 of the bridge coupler 600; the through-arm of the second directional coupler 64_2 is connected between the second RF input end 62_2 and the second input end P2 of the first RF bridge 61_1, and the coupled-arm of the second directional coupler 64_2 is connected to the calibration end 65 of the bridge coupler 600. The through-arm of the third directional coupler 64_3 is connected between the third RF input end 62_3 and the first input end P1 of the second RF bridge 61_2, and the coupled-arm of the third directional coupler 64_3 is connected to the calibration end 65 of the bridge coupler 600; the through-arm of the fourth directional coupler 64_4 is connected between the second RF input end 62_2 and the second input end P2 of the second RF bridge 61_2, and the coupled-arm of the fourth directional coupler 64_4 is connected to the calibration end 65 of the bridge coupler 600. The structure and working principle of the directional coupler in the bridge coupler 600 have been introduced in detail in the foregoing embodiments, and will not be elaborated again here.

[0111] A switch may be provided between the directional coupler and the calibration end of the bridge coupler. For example, the bridge coupler includes a first switch, a second switch, a third switch, and a fourth switch. The first switch is provided between the coupled-arm of the first directional coupler and the calibration end of the bridge coupler, and can be used to control the conduction state between the coupled-arm of the first directional coupler and the calibration end of the bridge coupler; the second switch is provided between the coupled-arm of the second directional coupler and the calibration end of the bridge coupler, and can be used to control the conduction state between the coupled-arm of the second directional coupler and the calibration end of the bridge coupler; the third switch is provided between the coupled-arm of the third directional coupler and the calibration end of the bridge coupler, and can be used to control the conduction state between the coupled-arm of the third directional coupler and the calibration end of the bridge coupler; the fourth switch is provided between the coupled-arm of the fourth directional coupler and the calibration end of the bridge coupler, and can be used to control the conduction state between the coupled-arm of the fourth directional coupler and the calibration end of the bridge coupler.

[0112] By switching the conduction states of the first switch, the second switch, the third switch, and the fourth switch, it is possible to determine whether there is a fault in the cable connection of the first RF input terminal to the fourth RF input terminal of the bridge coupler by detecting whether a signal is detected at the calibration terminal of the bridge coupler. For example, when the first switch, the second switch, and the third switch are switched to the off state and the fourth switch is switched to the on state, if no signal is detected at the calibration terminal of the bridge coupler, it indicates that the cable connected to the fourth RF input terminal of the bridge coupler may be faulty.

[0113] In another possible implementation, the bridge coupler further includes a calibration output terminal and a selection switch. The selection switch includes a fixed terminal, a first selection terminal, and a second selection terminal. The fixed terminal of the selection switch is connected to the calibration terminal of the bridge coupler. The first selection terminal of the selection switch is connected to the coupling arms of the first directional coupler, the second directional coupler, the third directional coupler, and the fourth directional coupler. The second selection terminal of the selection switch is connected to the calibration output terminal.

[0114] When the fixed terminal of the selection switch is conductive with the first selection terminal of the selection switch, the coupling arms of the first directional coupler, the second directional coupler, the third directional coupler, and the fourth directional coupler are connected to the calibration terminal of the RRU through the calibration terminal of the bridge coupler.

[0115] When the fixed terminal of the selection switch is conductive with the second selection terminal of the selection switch, the calibration terminal of the bridge coupler is connected to the calibration output terminal of the bridge coupler. The calibration output terminal can be connected to an antenna. In this way, it is equivalent to the calibration terminal of the RRU being connected to the antenna through the calibration terminal and the calibration output terminal of the bridge coupler, which can ensure the normal operation of the calibration loop between the RRU and the antenna.

[0116] Exemplarily, in this case, a first switch can also be provided between the coupling arm of the first directional coupler and the first selection terminal of the selection switch, a second switch can be provided between the coupling arm of the second directional coupler and the first selection terminal of the selection switch, a third switch can be provided between the coupling arm of the third directional coupler and the first selection terminal of the selection switch, and a fourth switch can be provided between the coupling arm of the fourth directional coupler and the first selection terminal of the selection switch. By switching the conduction states of the first switch, the second switch, the third switch, the fourth switch, and the selection switch, it is possible to detect the cable connection of the first RF input terminal, the second RF input terminal, the third RF input terminal, and the fourth RF output terminal of the bridge coupler. The specific principle has been introduced in the foregoing example and will not be elaborated here.

[0117] Figure 20The figure shows a schematic diagram of another communication system provided by an embodiment of the present application. The communication system includes a BBU 100, an RRU 200, a bridge coupler 600, and an antenna. The BBU 100 is connected to the RRU 200. The RRU 200 includes a first output channel, a second output channel, a third output channel, and a fourth output channel. Among them, the first output channel is connected to a first radio frequency input terminal 62_1, the second output channel is connected to a second radio frequency input terminal 62_2, the third output channel is connected to a third radio frequency input terminal 62_3, and the fourth output channel is connected to a fourth radio frequency input terminal 62_4. Multiple radio frequency output terminals of the bridge coupler 600 are all connected to the antenna, and a calibration terminal 65 of the bridge coupler 600 is connected to a calibration channel of the RRU 200.

[0118] Among them, the first output channel is used to output a first signal, the second output channel is used to output a second signal, the third output channel is used to output a third signal, and the fourth output channel is used to output a fourth signal. The first signal, the second signal, the third signal, and the fourth signal are signals obtained by processing the same signal source. The RRU 200 can achieve power distribution of the four input signals to any one output of the bridge coupler 600 by configuring the phases of the first signal, the second signal, the third signal, and the fourth signal in the digital domain. For example, if the phase of the first signal obtained by the first radio frequency input terminal 62_1 is 0°, the phase of the second signal obtained by the second radio frequency input terminal 62_2 is -90°, the phase of the third signal obtained by the third radio frequency input terminal 62_3 is -45°, and the phase of the fourth signal obtained by the fourth radio frequency input terminal 62_4 is 135°, then the power of the four input signals can be distributed to the first radio frequency output terminal 63_1 of the bridge coupler 600 for output, and the output signals of the remaining radio frequency output terminals are 0.

[0119] The bridge coupler provided by the embodiment of the present application can share the power of two signals to one output, or share the power of multiple signals to one output, which can improve the signal coverage ability and reduce power consumption. And the bridge coupler is provided with a calibration terminal and can output a calibration signal to ensure that the phase difference of the signals input into the bridge coupler meets the requirements. The bridge coupler can be connected to one RRU or different RRUs. According to the frequency bands of the adapted RRUs, the bridge coupler can support various frequency bands of FR1 such as 700 MHz, 800 MHz, 900 MHz, 1.8 GHz, 2.1 GHz, 2.3 GHz, 2.6 GHz, 3.5 GHz, 4.9 GHz, etc.; it can also support frequency bands of FR2 such as 24 GHz, 26 GHz, 28 GHz, 39 GHz, etc.

[0120] The bridge coupler provided by the embodiments of the present application can share the power of two or more signals to one output, and can improve the signal coverage ability without increasing the overall power consumption. It can be applied to scenarios such as railways and subway tunnels. For example, taking the railway as an example, base station equipment is built along the railway line, usually with a two-sector network; two antennas respectively cover both sides of the site along the railway; each antenna is respectively connected to an RRU device; the bridge coupler provided by the embodiments of the present application can be connected in series between the RRU and the antenna to realize the sharing of signal power between the two antennas.

[0121] The bridge coupler provided by the embodiments of the present application can also be applied to the subway tunnel scenario: leaky cables are installed inside the tunnel, and the leaky cables are disconnected at certain intervals. Different frequency band RRU devices are combined through a POI device and the radio frequency signals are fed into through the disconnected ports, and communication is realized through the leakage signals of the leaky cables; this bridge coupler can be connected in series between the RRU and the POI to realize the sharing of signal power between two sections of leaky cables.

[0122] The bridge coupler provided by the embodiments of the present application can also be applied to scenarios such as indoor distributed antenna system (DAS) and residential area spotlights: for example, the RRU is connected to multiple passive distributed antennas through passive feeders. Before the RRU feeds into the passive feeder, a bridge coupler can be connected first to realize the sharing of signal power between different passive antenna groups; or in the residential area, a single RRU on the roof is connected to two or more spotlight antennas, and a bridge coupler can be connected in series between the RRU and the spotlight antennas to realize the sharing of signal power between different spotlight antennas.

[0123] Based on the bridge coupler provided by the above embodiments, the embodiments of the present application also provide a heterodyne combiner integrated with a bridge coupler. The heterodyne combiner includes multiple input ends, multiple output ends, at least one filter, a calibration end, and the bridge coupler provided by the foregoing embodiments. Usually, the number of input ends of the heterodyne combiner is more than the number of output ends of the heterodyne combiner.

[0124] For example, refer to Figure 21 , Figure 21The figure shows a schematic diagram of an inter-frequency combiner provided by an embodiment of the present application. The inter-frequency combiner includes a first input terminal IN1, a second input terminal IN2, a third input terminal IN3, a fourth input terminal IN4, a filter F1, a filter F2, and a filter F3. The first input terminal IN1 of the inter-frequency combiner is connected to the input terminal of the filter F1. The second input terminal IN2 of the inter-frequency combiner is connected to the input terminal of the filter F2. The third input terminal IN3 of the inter-frequency combiner is connected to the first radio frequency input terminal 32_1 of the bridge coupler 300. The fourth input terminal IN4 of the inter-frequency combiner is connected to the second radio frequency input terminal 32_2 of the bridge coupler. The first radio frequency output terminal 33_1 and the second radio frequency output terminal 33_2 of the bridge combiner 300 are connected to the input terminal of the filter F3. The output terminals of the filter F1, the filter F2, and the filter F3 are combined and connected to the output terminal OUT1 of the inter-frequency combiner. The calibration terminal 35 of the bridge coupler 300 is connected to the calibration terminal C of the inter-frequency combiner. The first input terminal IN1 of the inter-frequency combiner can be used to connect to the output channel of the RRU 1. The second input terminal IN2 of the inter-frequency combiner can be used to connect to the output channel of the RRU 2. The third input terminal IN3 and the fourth input terminal IN4 of the inter-frequency combiner can be used to connect to two output channels of the RRU 3. The bridge combiner 300 can share the signal power output from the two output channels of the RRU 3 to the first radio frequency output terminal 33_1 or the second radio frequency output terminal 33_2 of the bridge coupler 300.

[0125] Figure 21 Taking the integration of the bridge coupler 300 in the foregoing example in the inter-frequency combiner as an example, the inter-frequency combiner can also integrate the bridge couplers provided in any of the foregoing embodiments.

[0126] As described above, the above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A bridge coupler, characterized in that, The bridge coupler includes a first RF input terminal, a second RF input terminal, a first RF bridge, a first RF output terminal, a second RF output terminal, a first directional coupler, a second directional coupler, and a calibration terminal; The first RF input terminal is connected to the first input terminal of the first RF bridge, the second RF input terminal is connected to the second input terminal of the first RF bridge, the first RF output terminal is connected to the first output terminal of the first RF bridge, and the second RF output terminal is connected to the second output terminal of the first RF bridge; The through arm of the first directional coupler is connected between the first RF input terminal and the first input terminal of the first RF bridge, and the coupled arm of the first directional coupler is connected to the calibration terminal of the bridge coupler; The through arm of the second directional coupler is connected between the second RF input terminal and the second input terminal of the first RF bridge, and the coupled arm of the second directional coupler is connected to the calibration terminal of the bridge coupler; The first RF input terminal is used to obtain a first signal, the second RF input terminal is used to obtain a second signal, the first signal and the second signal are signals obtained by processing the same signal source, and the phase difference between the first signal and the second signal is 90°; 2. The bridge coupler according to claim 1, wherein The bridge coupler further includes a selection switch and a calibration output terminal; The selection switch includes a fixed terminal, a first selection terminal, and a second selection terminal. The fixed terminal is connected to the calibration terminal of the bridge coupler, the first selection terminal is connected to the coupled arm of the first directional coupler, and the first selection terminal is also connected to the coupled arm of the second directional coupler; The second selection terminal is connected to the calibration output terminal; 3. The bridge coupler according to claim 1 or 2, wherein The bridge coupler further includes a first switch and a second switch. The first switch is connected between the coupled arm of the first directional coupler and the calibration terminal of the bridge coupler, and the second switch is connected between the coupled arm of the second directional coupler and the calibration terminal of the bridge coupler; 4. The bridge coupler according to claim 1, wherein The bridge coupler further includes a third RF input terminal, a fourth RF input terminal, a second RF bridge, a third RF output terminal, a fourth RF output terminal, a third directional coupler, and a fourth directional coupler; The third RF input terminal is connected to the first input terminal of the second RF bridge, the fourth RF input terminal is connected to the second input terminal of the second RF bridge, the third RF output terminal is connected to the first output terminal of the second RF bridge, and the fourth RF output terminal is connected to the second output terminal of the second RF bridge; The through arm of the third directional coupler is connected between the third RF input terminal and the first input terminal of the second RF bridge, and the coupled arm of the third directional coupler is connected to the calibration terminal of the bridge coupler; The through arm of the fourth directional coupler is connected between the second RF input terminal and the second input terminal of the second RF bridge, and the coupled arm of the fourth directional coupler is connected to the calibration terminal of the bridge coupler; The third RF input terminal is used to obtain a third signal, and the fourth RF input terminal is used to obtain a fourth signal. The third signal and the fourth signal are signals obtained by processing the same signal source, and the phase difference between the third signal and the fourth signal is 90°.

5. The bridge coupler according to claim 4, wherein The bridge coupler further includes a selection switch and a calibration output terminal; The selection switch includes a fixed terminal, a first selection terminal, and a second selection terminal. The fixed terminal is connected to the calibration terminal of the bridge coupler, and the first selection terminal is connected to the coupling arms of the first directional coupler, the second directional coupler, the third directional coupler, and the fourth directional coupler; The second selection terminal is connected to the calibration output terminal of the bridge coupler.

6. The bridge coupler according to claim 4 or 5, characterized in that, The bridge coupler further includes a first switch, a second switch, a third switch, and a fourth switch; The first switch is connected between the coupling arm of the first directional coupler and the calibration terminal of the bridge coupler; The second switch is connected between the coupling arm of the second directional coupler and the calibration terminal of the bridge coupler; The third switch is connected between the coupling arm of the third directional coupler and the calibration terminal of the bridge coupler; The second switch is connected between the coupling arm of the fourth directional coupler and the calibration terminal of the bridge coupler.

7. A communication system, characterized in that, The communication system includes the bridge coupler according to any one of claims 1 to 6 and a first RF remote unit; The first RF remote unit includes a first output channel, a second output channel, and a calibration terminal. The first output channel of the first RF remote unit is connected to the first RF input terminal of the bridge coupler, the second output channel of the first RF remote unit is connected to the second RF input terminal of the bridge coupler, and the calibration terminal of the first RF remote unit is connected to the calibration terminal of the bridge coupler; The first RF remote unit is used to output a first signal through the first output channel of the first RF remote unit and output a second signal through the second output channel of the first RF remote unit. The first signal and the second signal are signals obtained by processing the same signal source, and the phase difference between the first signal and the second signal is 90°.

8. The communication system according to claim 7, characterized in that, The communication system further includes a first antenna and a second antenna. The bridge coupler includes a first RF output terminal and a second RF output terminal. The first RF output terminal is connected to the first antenna, and the second RF output terminal is connected to the second antenna.

9. The communication system according to claim 7 or 8, characterized in that, The bridge coupler includes a third RF input terminal and a fourth RF input terminal. The communication system further includes a second RF remote unit. The second RF remote unit includes a first output channel and a second output channel; The first output channel of the second RF remote unit is connected to the third RF input terminal of the bridge coupler, and the second output channel of the second RF remote unit is connected to the fourth RF input terminal of the bridge coupler; The second radio frequency remote unit is configured to output a third signal through the first output channel of the second radio frequency remote unit, and output a fourth signal through the second output channel of the second radio frequency remote unit, and the phase difference between the third signal and the fourth signal is 90°.

10. A heterodyne combiner, characterized in that, The different-frequency combiner includes: a plurality of input terminals, a filter, a calibration terminal, and a bridge coupler according to any one of claims 1 to 6; The first radio frequency input terminal is connected to the first input terminal among the plurality of input terminals of the different-frequency combiner, the second radio frequency input terminal is connected to the second input terminal among the plurality of input terminals of the different-frequency combiner, the first radio frequency output terminal and the second radio frequency output terminal are connected to the input terminal of the filter, and the calibration terminal of the bridge coupler is connected to the calibration terminal of the different-frequency combiner.

11. A bridge coupler, characterized in that, The bridge coupler includes a first radio frequency input terminal, a second radio frequency input terminal, a third radio frequency input terminal, a fourth radio frequency input terminal, a first radio frequency bridge, a second radio frequency bridge, a first radio frequency output terminal, a second radio frequency output terminal, a third radio frequency output terminal, a fourth radio frequency output terminal, a first directional coupler, a second directional coupler, a third directional coupler, a fourth directional coupler, a first 45° phase shifter, a second 45° phase shifter, and a calibration terminal; The first radio frequency input terminal is connected to the first input terminal of the first radio frequency bridge, the first output terminal of the first radio frequency bridge is connected to the first input terminal of the third radio frequency bridge through the first 45° phase shifter, and the first output terminal of the third radio frequency bridge is connected to the first radio frequency output terminal; The second radio frequency input terminal is connected to the second input terminal of the first radio frequency bridge, the second output terminal of the first radio frequency bridge is connected to the first input terminal of the fourth radio frequency bridge, and the first output terminal of the fourth radio frequency bridge is connected to the third radio frequency output terminal; The third radio frequency input terminal is connected to the first input terminal of the second radio frequency bridge, the first output terminal of the second radio frequency bridge is connected to the second input terminal of the third radio frequency bridge, and the second output terminal of the third radio frequency bridge is connected to the second radio frequency output terminal; The fourth radio frequency input terminal is connected to the second input terminal of the second radio frequency bridge, the second output terminal of the second radio frequency bridge is connected to the second input terminal of the fourth radio frequency bridge through the second 45° phase shifter, and the second output terminal of the fourth radio frequency bridge is connected to the fourth radio frequency output terminal; The through arm of the first directional coupler is connected between the first RF input terminal and the first input terminal of the first RF bridge, and the coupled arm of the first directional coupler is connected to the calibration terminal; the through arm of the second directional coupler is connected between the second RF input terminal and the second input terminal of the first RF bridge, and the coupled arm of the second directional coupler is connected to the calibration terminal; the through arm of the third directional coupler is connected between the third RF input terminal and the first input terminal of the second RF bridge, and the coupled arm of the third directional coupler is connected to the calibration terminal; the through arm of the fourth directional coupler is connected between the second RF input terminal and the second input terminal of the second RF bridge, and the coupled arm of the fourth directional coupler is connected to the calibration terminal.

12. A communication system, characterized in that, The communication system includes a bridge coupler as claimed in claim 11 and a remote radio unit; The remote radio unit includes a first output channel, a second output channel, a third output channel, a fourth output channel and a calibration terminal. The first output channel of the remote radio unit is connected to the first RF input terminal of the bridge coupler, the second output channel of the remote radio unit is connected to the second RF input terminal of the bridge coupler, the third output channel of the remote radio unit is connected to the third RF input terminal of the bridge coupler, the fourth output channel of the remote radio unit is connected to the fourth RF input terminal of the bridge coupler, and the calibration terminal of the remote radio unit is connected to the calibration terminal of the bridge coupler.

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