Communication module and communication system

Abstract

The embodiment of the invention provides a communication module and a communication system, the communication module comprises a combining and splitting unit and a digital-to-analog conversion unit, the combining and splitting unit is connected with the digital-to-analog conversion unit, and a digital signal is transmitted between the combining and splitting unit and the digital-to-analog conversion unit; the combining and splitting unit is used for combining multi-carrier signals into one path of digital signals in a first transmission direction and transmitting the digital signals to the digital-to-analog conversion unit, and splitting one path of digital signals received from the digital-to-analog conversion unit into multiple paths of multi-carrier signals in a second transmission direction; the digital-to-analog conversion unit is used for converting a digital signal received from the combining and splitting unit into an analog signal in the first transmission direction, converting the received analog signal into a digital signal in the second transmission direction and transmitting the digital signal to the combining and splitting unit; the transmission efficiency is greatly improved at low cost.

Description

Communication modules and communication systems Technical Field

[0001] The embodiments of the present application relate to the field of communication technology, and in particular to a communication module and a communication system. Background Art

[0002] The baseband unit (BBU) is a communication system or functional module with baseband signal processing functions, and the radio unit (RU) is a communication system or functional module with intermediate frequency signals, radio frequency signals, or intermediate radio frequency signal processing functions. The baseband unit (BBU) and the radio frequency unit (RU) are connected by optical fiber.

[0003] In related technologies, the Common Public Radio Interface (CPRI) is often used for signal transmission between the BBU and RU. The CPRI interface uses a digital method to transmit baseband signals. Due to cost and power consumption, digital signals transmitted on the CPRI interface are generally not suitable for high-order modulation. Instead, digital signals transmitted on the CPRI interface often use low-order modulation such as Non-Return-to-Zero (NRZ) or Pulse Amplitude Modulation (PAM).

[0004] However, with the rapid increase in mobile communication traffic, the use of low-order modulation cannot better approach the channel's maximum capacity, causing the capacity of the CPRI interface to become a bottleneck for the entire base station system capacity. Especially when the number of channels increases significantly, the CPRI interface can no longer meet the transmission capacity requirements of Massive Multiple Input Multiple Output (Massive MIMO).

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a communication module and a communication system, which realize analog signal transmission between two communication systems, thereby significantly improving the transmission efficiency of the systems and reducing communication costs.

[0007] In the first aspect, an embodiment of the present application provides a communication module, comprising: a combining and splitting unit and a digital-to-analog conversion unit, wherein the digital-to-analog conversion unit is located on one side of the combining and splitting unit, and the combining and splitting unit is connected to the digital-to-analog conversion unit, and digital signals are transmitted between the combining and splitting unit and the digital-to-analog conversion unit; the combining and splitting unit is used to combine multi-carrier signals into one digital signal in a first transmission direction and transmit it to the digital-to-analog conversion unit, and to split one digital signal received from the digital-to-analog conversion unit into multiple multi-carrier signals in a second transmission direction; the digital-to-analog conversion unit is used to convert the digital signal received from the combining and splitting unit into an analog signal in the first transmission direction, and to convert the received analog signal into a digital signal in the second transmission direction and transmit it to the combining and splitting unit; one of the first transmission direction and the second transmission direction is an uplink direction, and the other is a downlink direction.

[0008] The communication module provided by the embodiment of the present application is provided with a combining and splitting unit and a digital-to-analog conversion unit, so that the combining and splitting unit can combine the received multi-carrier signals to generate digital signals, and the digital-to-analog conversion unit converts the digital signals into analog signals and sends the analog signals. In this way, when the communication module is a baseband unit, the analog signals are transmitted between the communication module and other modules (such as the radio frequency unit), and the analog signals can be high-order modulated. In this way, the analog carrier signal has been high-order modulated on the baseband side, so there is no need to perform high-order modulation again, achieving a significant improvement in transmission efficiency at a low cost. Therefore, the communication module provided by the embodiment of the present application effectively improves the transmission efficiency between the communication module and other modules, greatly improves the transmission capacity of the channel, and can meet the transmission capacity requirements of Massive MIMO. In addition, there is no need to perform high-order modulation again, which reduces costs and avoids excessive power consumption.

[0009] In one feasible implementation, the system further includes an intermediate frequency unit, the intermediate frequency unit being located on the other side of the combiner / splitter unit and connected to the combiner / splitter unit, and transmitting digital signals between the intermediate frequency unit and the combiner / splitter unit. Thus, in the second transmission direction, the intermediate frequency unit can filter and frequency convert the multi-carrier digital signals received from the combiner / splitter unit, thereby meeting 3GPP performance requirements.

[0010] In a feasible implementation, the intermediate frequency unit includes: a digital filter and a digital channel, the digital filter is connected to the combining and splitting unit, and the digital signal is transmitted between the digital filter and the combining and splitting unit; the digital filter is used to filter the digital signal received from the combining and splitting unit and transmit it through the digital channel; the digital channel is connected to the digital filter, and the digital signal is transmitted between the digital channel and the digital filter; the digital channel is used to perform frequency conversion processing on the digital signal filtered by the digital filter.

[0011] Through digital filters, on the one hand, the signal edges are made extremely steep to meet the 3GPP adjacent channel leakage ratio (ACLR) indicator requirements, and on the other hand, the SNR (dynamic) requirements for the transmission link are greatly reduced.

[0012] In one feasible implementation, the digital-to-analog conversion unit includes: an analog-to-digital converter and a digital-to-analog converter, wherein the analog-to-digital converter and the digital-to-analog converter are arranged in parallel; the analog-to-digital converter is used to convert a received analog signal in the second transmission direction into a digital signal and transmit it to the combining and splitting unit; and the digital-to-analog converter is used to convert a digital signal received from the combining and splitting unit into an analog signal in the first transmission direction. By providing the analog-to-digital converter and the digital-to-analog converter, and by using high-speed converters, a larger number of channels can be supported, thereby significantly improving transmission efficiency.

[0013] In a feasible implementation, the combining and splitting unit includes: a combiner and a splitter, the combiner and the splitter are arranged in parallel; the combiner is used to combine multi-carrier signals into one digital signal in the first transmission direction and transmit it to the digital-to-analog conversion unit; the splitter is used to split the digital signal received from the analog-to-digital converter into multiple multi-carrier signals in the second transmission direction.

[0014] In a feasible implementation, it further includes: a correction unit, which is connected to the combining and splitting unit.

[0015] In a feasible implementation, the communication module is a baseband unit.

[0016] In a feasible implementation, the communication module is a radio frequency unit.

[0017] In the second aspect, an embodiment of the present application provides a communication system, comprising: a first communication module and a second communication module, the first digital-to-analog conversion unit is located on one side of the first combining and splitting unit, and analog signals are transmitted between the first communication module and the second communication module; the first communication module comprises: a first combining and splitting unit and a first digital-to-analog conversion unit, the first combining and splitting unit and the first digital-to-analog conversion unit are connected, and digital signals are transmitted between the first combining and splitting unit and the first digital-to-analog conversion unit; the second communication module comprises: a second combining and splitting unit and a second digital-to-analog conversion unit, the second digital-to-analog conversion unit is located on one side of the second combining and splitting unit, the second combining and splitting unit and the second digital-to-analog conversion unit are connected, and digital signals are transmitted between the second combining and splitting unit and the second digital-to-analog conversion unit; the first combining and splitting unit is used to synthesize multi-carrier signals into one digital signal in the first transmission direction and transmit it to the first digital-to-analog conversion unit, and to split one digital signal received from the first digital-to-analog conversion unit into one digital signal in the second transmission direction. into multiple multi-carrier signals; the first digital-to-analog conversion unit is used to convert the digital signal received from the first combining and splitting unit into an analog signal in the first transmission direction and transmit it to the second digital-to-analog conversion unit, and to convert the received analog signal into a digital signal in the second transmission direction and transmit it to the first combining and splitting unit; the second combining and splitting unit is used to synthesize the multi-carrier signals into one digital signal in the second transmission direction and transmit it to the second digital-to-analog conversion unit, and to split one digital signal received from the second digital-to-analog conversion unit into multiple multi-carrier signals in the first transmission direction; the second digital-to-analog conversion unit is used to convert the digital signal received from the second combining and splitting unit into an analog signal in the second transmission direction and transmit it to the first digital-to-analog conversion unit, and to convert the received analog signal into a digital signal in the first transmission direction and transmit it to the second combining and splitting unit, the first transmission direction is a downlink direction, and the second transmission direction is an uplink direction.

[0018] In this way, the first communication module and the second communication module transmit analog signals, and the analog signals can be modulated in a high-order manner. The analog carrier signal has been subjected to high-order modulation on the baseband side. Therefore, there is no need to perform high-order modulation again, thereby achieving a significant improvement in transmission efficiency at a low cost. Therefore, the communication system provided in the embodiment of the present application effectively improves the transmission efficiency between a communication module (such as a baseband unit) and another communication module (such as a radio frequency unit), greatly improves the transmission capacity of the channel, and can thus meet the transmission capacity requirements of Massive MIMO. In addition, there is no need for an additional high-order modulation, which reduces costs and avoids excessive power consumption.

[0019] In a feasible implementation, the second communication module further includes: an intermediate frequency unit, the intermediate frequency unit is connected to the second combining / splitting unit, and digital signals are transmitted between the intermediate frequency unit and the second combining / splitting unit.

[0020] In one feasible implementation, the intermediate frequency unit includes: a digital filter and a digital channel. The digital filter is connected to the second combiner / splitter unit, and digital signals are transmitted between the digital filter and the second combiner / splitter unit. The digital filter is configured to filter the multi-carrier signal received from the second combiner / splitter unit. The digital channel is connected to the digital filter, and digital signals are transmitted between the digital channel and the digital filter. The digital channel is configured to perform frequency conversion processing on the digital signal filtered by the digital filter.

[0021] In a feasible implementation, the digital channel includes: a first digital channel and a second digital channel, the first digital channel is connected to the digital filter, and digital signals are transmitted between the first digital channel and the digital filter; the second digital channel is connected to the second combining and splitting unit, and digital signals are transmitted between the second digital channel and the second combining and splitting unit.

[0022] In a feasible implementation, the first communication module further includes: a first correction unit, the first correction unit is connected to the first combining / splitting unit, and the first correction unit is located on the other side of the first combining / splitting unit.

[0023] In a feasible implementation, the second communication module further includes: a second correction unit, the second correction unit is connected to the second combining / splitting unit, and the second correction unit is located on the other side of the second combining / splitting unit.

[0024] In a feasible implementation, the first communication module is a baseband unit, and the second communication module is a radio frequency unit.

[0025] In a feasible implementation, one of the first communication module and the second communication module is a carrier chip, and the other of the first communication module and the second communication module is an intermediate frequency chip.

[0026] In a feasible implementation, the communication system is located in the same communication device, and the communication device is a radio frequency unit.

[0027] In a feasible implementation, analog signals are transmitted between the first communication module and the second communication module via any one of transmission media including optical fiber, cable, microwave, and free space laser communication (FSO). BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a schematic diagram of the structure of signal transmission between a BBU and a RU;

[0029] FIG2A is a structural block diagram of a communication module provided in an embodiment of the present application;

[0030] FIG2B is another structural block diagram of a communication module provided in one embodiment of the present application;

[0031] FIG2C is another structural block diagram of a communication module provided in an embodiment of the present application;

[0032] FIG3A is a structural block diagram of another communication module provided in an embodiment of the present application;

[0033] FIG3B is a structural block diagram of another communication module provided in an embodiment of the present application;

[0034] FIG3C is a structural block diagram of another communication module provided in an embodiment of the present application;

[0035] FIG4 is a structural block diagram of another communication module provided in an embodiment of the present application;

[0036] FIG5 is a schematic structural diagram of a communication system provided in an embodiment of the present application;

[0037] FIG6A is another schematic structural diagram of a communication system provided by an embodiment of the present application;

[0038] FIG6B is another structural diagram of a communication system provided by an embodiment of the present application;

[0039] FIG6C is another structural diagram of a communication system provided by an embodiment of the present application;

[0040] FIG7 is a schematic diagram of an application scenario of a communication system provided in an embodiment of the present application.

[0041] Description of reference numerals:

[0042] 100 - communication module; 110 - combining and splitting unit; 120 - digital-to-analog conversion unit; 160 - correction unit; 110b - combiner; 110a - splitter; 111 - first combining and splitting unit; 112 - first digital-to-analog conversion unit; 121 - second combining and splitting unit; 122 - second digital-to-analog conversion unit; 120a - analog-to-digital converter; 120b - digital-to-analog converter; 113 - first correction unit; 123 - second correction unit;

[0043] 130-intermediate frequency unit; 131-first digital channel; 132-second digital channel; 133-digital filter; 134-digital channel;

[0044] 140-sending unit; 150 receiving unit;

[0045] 200-Communication system; 201-Radio access network; 202-Core network; 203-Internet. DETAILED DESCRIPTION

[0046] Figure 1 is a schematic diagram of the structure of signal transmission between a baseband unit (BBU) and a radio unit (RU). As shown in Figure 1, the interface between the baseband unit (BBU) and the radio unit (RU) is often a Common Public Radio Interface (CPRI) interface. The CPRI interface is based on digital transmission. For example, digital signals are transmitted between the BBU and the RU. As shown in Figure 1, in the downlink direction, the carrier signal generated by the BBU side is compressed and exchanged by the CPRI group deframe 11 and transmitted as a digital signal to the serializer / deserializer 12. The serializer / deserializer 12 converts the digital signal into serial data and transmits the digital signal to the RU side. The serializer / deserializer 21 on the RU side converts the received serial data into parallel data and transmits the digital signal to the CPRI group deframe 22 on the RU side. The CPRI group deframe 22 on the RU side decompresses and deframes the received parallel data to generate a carrier signal. The signal transmission in the uplink direction is opposite to the signal transmission in the downlink direction.

[0047] Because the CPRI interface transmits digital carrier signals, which are modulated at the baseband, digital signals are often modulated using low-order modulation schemes such as Non-Return-to-Zero (NRZ) or Pulse Amplitude Modulation (PAM). However, when digitally transmitted over the CPRI interface, the baseband modulation results cannot improve CPRI transmission efficiency or better approach the channel's maximum capacity. Especially when the number of channels increases significantly, the CPRI interface can no longer meet the transmission capacity requirements of Massive MIMO (Massive Multiple-Input Multiple-Output Antenna Array). Therefore, the capacity of the CPRI interface has become a bottleneck for the entire base station system. To improve CPRI transmission efficiency, the digital signal must be subjected to additional high-order modulation. However, high-order modulation increases the cost and power consumption, making it unbearable for the base station system.

[0048] In order to solve the above problems, in an embodiment of the present application, the digital carrier signal transmitted between the BBU and the RU is adjusted to transmit an analog carrier signal. The analog carrier signal can adopt high-order modulation. In this way, the analog carrier signal has been subjected to high-order modulation on the baseband side. Therefore, there is no need to perform high-order modulation again, thereby achieving a significant improvement in transmission efficiency at a low cost.

[0049] The structure of the communication module and communication system provided in the embodiments of the present application are described in detail below.

[0050] As shown in FIG2A , an embodiment of the present application provides a communication module 100. The communication module 100 may be a baseband unit or a radio frequency unit. FIG2A takes the communication module 100 as an example for description as a baseband unit. As shown in FIG2A , the communication module 100 may include: a combiner / splitter unit 110 and a digital-to-analog converter unit 120. The digital-to-analog converter unit 120 is located on one side of the combiner / splitter unit 110. For example, in FIG2A , the digital-to-analog converter unit 120 is located on the right side of the combiner / splitter unit 110. The combiner / splitter unit 110 is connected to the digital-to-analog converter unit 120, and digital signals are transmitted between the combiner / splitter unit 110 and the digital-to-analog converter unit 120.

[0051] In which, in the first transmission direction (for example, the direction of the solid arrow in Figure 2A), the combining and splitting unit 110 combines the multi-carrier signals into one digital signal, and transmits the combined digital signal to the digital-to-analog conversion unit 120, and the digital-to-analog conversion unit 120 converts the digital signal received from the combining and splitting unit 110 into an analog signal.

[0052] In the second transmission direction (for example, the direction of the dotted arrow in Figure 2A), the digital-to-analog conversion unit 120 converts the received analog signal into a digital signal, and transmits the converted digital signal to the combining and splitting unit 110. The combining and splitting unit 110 splits the digital signal received from the digital-to-analog conversion unit 120 into multiple multi-carrier signals.

[0053] In the embodiment of the present application, one of the first transmission direction and the second transmission direction is an uplink direction, and the other is a downlink direction. For example, in FIG2A , the first transmission direction is a downlink direction, and the second transmission direction is an uplink direction. Of course, in some examples, the first transmission direction may also be an uplink direction, and the second transmission direction may be a downlink direction. For example, when the communication module functions as a BBU, the first transmission direction is a downlink direction, and the second transmission direction is an uplink direction. When the communication module functions as an RU, the first transmission direction is an uplink direction, and the second transmission direction is a downlink direction.

[0054] In the embodiment of the present application, the multi-carrier signal received by the combining and splitting unit 110 may be a downlink multi-carrier signal, and the multiple multi-carrier signals branched by the combining and splitting unit 110 may be an uplink multi-carrier signal.

[0055] The communication module 100 provided in the embodiment of the present application is provided with a combining and splitting unit 110 and a digital-to-analog conversion unit 120, so that the combining and splitting unit 110 can combine the received multi-carrier signals to generate digital signals, and the digital-to-analog conversion unit 120 converts the digital signals into analog signals and sends the analog signals. In this way, when the communication module 100 is a baseband unit, the analog signals are transmitted between the communication module 100 and other modules (such as the radio frequency unit), and the analog signals can be high-order modulated. In this way, the analog carrier signal has been high-order modulated on the baseband side, so there is no need to perform high-order modulation again, thereby achieving a significant improvement in transmission efficiency at a low cost. Therefore, the communication module 100 provided in the embodiment of the present application effectively improves the transmission efficiency between the communication module 100 and other modules, greatly improves the transmission capacity of the channel, and can meet the transmission capacity requirements of Massive MIMO. In addition, there is no need to perform high-order modulation again, which reduces costs and avoids excessive power consumption.

[0056] In an embodiment of the present application, as shown in FIG2B , when the combining and splitting unit 110 receives a multi-carrier signal for transmission in the first transmission direction, the combining and splitting unit 110 can also receive a corresponding control signal and a synchronization signal in the first transmission direction. The synchronization signal may include at least one of a clock synchronization signal and a phase synchronization signal, and the control signal, the synchronization signal and the multi-carrier signal are combined by the combining and splitting unit 110 to form one or more groups of digital signals. In the second transmission direction, when the combining and splitting unit 110 splits the digital signal received from the digital-to-analog conversion unit 120 into a multi-carrier signal, the combining and splitting unit 110 also separates the control signal. In an embodiment of the present application, the control signal is used to control the interaction of control information between the communication module 100 (e.g., BBU) and another connected communication module (e.g., RU). The synchronization signal is used to meet the synchronization requirements for the signal transmitted in the first transmission direction or the second transmission direction.

[0057] In the embodiment of the present application, digital signals are transmitted between the combiner / splitter unit 110 and the digital-to-analog converter 120. When digital signals are used for transmission, a correction algorithm can be used to correct the digital signals, thereby improving the signal-to-noise ratio (SNR). However, if analog signals are used for transmission between the combiner / splitter unit 110 and the digital-to-analog converter 120, the analog signals cannot be corrected, and thus, the performance requirements of the Third Generation Partnership Project (3GPP), such as the adjacent channel leakage ratio (ACLR) and error vector magnitude (EVM) in the 3GPP performance, cannot be met.

[0058] Therefore, in an embodiment of the present application, as shown in Figure 2C, the communication module 100 also includes: a correction unit 160, which is connected to the combining and splitting unit 110. The correction unit 160 is used to correct the digital signal between the combining and splitting unit 110 and the digital-to-analog conversion unit 120 in the first transmission direction, so that the digital signal can meet the 3GPP performance requirements.

[0059] In an embodiment of the present application, in a possible implementation, as shown in Figure 2C, the combining and splitting unit 110 includes: a combiner 110b and a splitter 110a. The combiner 110b and the splitter 110a can be arranged in parallel. The combiner 110b is used to combine the multi-carrier signal into one digital signal in the first transmission direction and transmit it to the digital-to-analog conversion unit 120. The splitter 110a is used to split the digital signal received from the analog-to-digital converter into multiple multi-carrier signals in the second transmission direction.

[0060] In one possible implementation, as shown in Figure 2C, the digital-to-analog conversion unit 120 includes: an analog-to-digital converter (ADC) 120a and a digital-to-analog converter (DAC) 120b, the analog-to-digital converter 120a and the digital-to-analog converter 120b are arranged in parallel, the analog-to-digital converter 120a is used to convert the received analog signal into a digital signal in the second transmission direction and transmit it to the splitter 110a of the combining and splitting unit 110, and the digital-to-analog converter 120b is used to convert the digital signal received from the combiner 110b of the combining and splitting unit 110 in the first transmission direction into an analog signal.

[0061] Among them, in the embodiment of the present application, both ADC and DAC are ultra-high-speed converters, one ADC can support dozens of channels, and one DAC can support dozens of channels, or even a higher number of channels, thereby greatly improving the transmission efficiency.

[0062] In an embodiment of the present application, the communication module 100 can also be a radio frequency unit. The following description is taken as an example of the communication module 100 being a radio frequency unit. Referring to Figure 3A, when the communication module 100 is used as a radio frequency unit, the first transmission direction can be an uplink direction, such as the dotted arrow in Figure 3A, and the second transmission direction can be a downlink direction, such as the solid arrow direction in Figure 3A.

[0063] 3A , in a first transmission direction (e.g., the direction of the dotted arrows in FIG3A ), the combiner / splitter unit 110 combines the multi-carrier signals into one digital signal, and transmits the combined digital signal to the digital-to-analog converter 120. The digital-to-analog converter 120 converts the digital signal received from the combiner / splitter unit 110 into an analog signal. In a second transmission direction (e.g., the direction of the solid arrows in FIG3A ), the digital-to-analog converter 120 converts the received analog signal into a digital signal, and transmits the converted digital signal to the combiner / splitter unit 110. The combiner / splitter unit 110 splits the one digital signal received from the digital-to-analog converter 120 into multiple multi-carrier signals.

[0064] In this way, what is transmitted between the radio frequency unit and other modules (such as the baseband unit) is an analog signal, and the analog signal can be subjected to high-order modulation. In this way, the analog carrier signal has been subjected to high-order modulation on the baseband side, so there is no need to perform high-order modulation again, achieving a significant improvement in transmission efficiency at a low cost. Therefore, the communication module 100 provided in the embodiment of the present application effectively improves the transmission efficiency between the communication module 100 and other modules, greatly increases the transmission capacity of the channel, and can thus meet the transmission capacity requirements of Massive MIMO. In addition, there is no need for an additional high-order modulation, which reduces costs and avoids excessive power consumption.

[0065] As shown in FIG3B , when the communication module 100 is a radio frequency unit, in the first transmission direction, when the combiner / splitter unit 110 receives a multi-carrier signal for transmission, the combiner / splitter unit 110 can also receive a corresponding control signal in the first transmission direction, wherein the control signal and the multi-carrier signal are combined by the combiner / splitter unit 110 to form one or more groups of digital signals. In the second transmission direction, when the combiner / splitter unit 110 splits the digital signal received from the digital-to-analog conversion unit 120 into multiple carrier signals, the combiner / splitter unit 110 also splits the control signal and the synchronization signal. The synchronization signal can include at least one of a clock synchronization signal and a phase synchronization signal.

[0066] In the embodiment of the present application, the functions of the control signal and the synchronization signal can be referred to the above description and will not be repeated in the embodiment of the present application.

[0067] As shown in Figure 3C, when the communication module 100 is a radio frequency unit, the communication module 100 also includes: a correction unit 160, which is connected to the combining and splitting unit 110. The correction unit 160 is used to correct the digital signal between the combining and splitting unit 110 and the digital-to-analog conversion unit 120 in the first transmission direction, so that the digital signal can meet the 3GPP performance requirements.

[0068] In one possible implementation, when the communication module 100 is a radio frequency unit, as shown in FIG4 , the communication module 100 further includes an intermediate frequency unit 130, which is located on the other side of the combiner / splitter unit 110. For example, in FIG4 , the intermediate frequency unit 130 is located on the right side of the combiner / splitter unit 110, and the digital-to-analog conversion unit 120 is located on the left side of the combiner / splitter unit 110. The intermediate frequency unit 130 is connected to the combiner / splitter unit 110, and digital signals are transmitted between the intermediate frequency unit 130 and the combiner / splitter unit 110. In the second transmission direction, the multi-carrier digital signals received by the intermediate frequency unit 130 from the combiner / splitter unit 110 can be filtered and frequency-converted to meet 3GPP performance requirements.

[0069] In the embodiment of the present application, as shown in FIG4 , in the second transmission direction, the combining and splitting unit 110 receives a digital signal from the digital-to-analog conversion unit 120. Furthermore, the combining and splitting unit 110 splits the digital signal into multiple carrier signals, which are then converted into digital signals. This allows the intermediate frequency unit 130 to filter the digital signal, and filtering the digital signal can meet the 3GPP requirements for ACLR and EVM. Furthermore, filtering the digital signal significantly reduces the SNR (dynamic) requirements for the transmission link. In an embodiment of the present application, the intermediate frequency unit 130 includes: a digital filter 133 and a digital channel 134. The digital filter 133 is connected to the combiner / splitter unit 110, and digital signals are transmitted between the digital filter 133 and the combiner / splitter unit 110. The digital filter 133 is used to filter the digital signal received from the combiner / splitter unit 110 and transmit it through the digital channel 134 (for example, the first digital channel 131 described below). Through the digital filter 133, on the one hand, the transition band of the digital filter is made very narrow and the transition band edge is made extremely steep to meet the 3GPP indicator requirements for adjacent channel leakage ratio (ACLR). On the other hand, the SNR (dynamic) requirements for the transmission link are greatly reduced.

[0070] In the embodiment of the present application, the digital filter 133 may be a shaping filter, which may filter the digital signal and use a CPRI interface.

[0071] 4 , digital channel 134 is connected to digital filter 133 , and digital signals are transmitted between digital channel 134 and digital filter 133 . Digital channel 134 is used to perform frequency conversion processing on the digital signal filtered by digital filter 133 . In some examples, digital channel 134 may also be connected to combining / splitting unit 110 .

[0072] As shown in Figure 4, the digital channel 134 may include a first digital channel 131 and a second digital channel 132. The first digital channel 131 is connected to the digital filter 133. The digital signal is transmitted between the first digital channel 131 and the digital filter 133. The first digital channel 131 performs frequency conversion processing on the digital signal filtered by the digital filter 133.

[0073] Among them, the second digital channel 132 is connected to the combining and splitting unit 110. The second digital channel 132 performs frequency conversion processing on the received multi-carrier signal and sends it to the combining and splitting unit 110 after processing. The second digital channel 132 processes the multi-carrier signal in the first transmission direction, so that the SNR of the multi-carrier signal is improved.

[0074] In a possible implementation, as shown in FIG4 , the communication module 100 further includes a receiving unit 150 and a sending unit 140 . The receiving unit 150 can receive a multi-carrier signal, and the sending unit 140 can send the digital multi-carrier signal transmitted by the first digital channel 131 .

[0075] The embodiment of the present application also provides a communication system 200, wherein different parts of the communication system 200 may be located in different communication devices, for example, the communication system is located in a distributed base station; or, the communication system 200 is located in the same communication device, which may be an integrated base station or a radio frequency unit (RU). In the embodiment of the present application, the communication system 200 is specifically described by taking the communication system 200 located in the same communication device, which is a radio frequency unit, as an example. Referring to FIG5 , the communication system 200 may include a first communication module 101 and a second communication module 102, and analog signals are transmitted between the first communication module 101 and the second communication module 102. When the communication device is a radio frequency unit, the first communication module 101 may be a master chip, such as a multi-carrier chip, and the second communication module 102 may also be a slave chip, such as an intermediate frequency chip. Analog signals are transmitted between the master chip and the slave chip, which can improve the transmission efficiency between the master chip and the slave chip.

[0076] 5 , the first communication module 101 may include a first combining / splitting unit 111 and a first digital-to-analog conversion unit 112. The first digital-to-analog conversion unit 112 is located on one side of the first combining / splitting unit 111. For example, in FIG5 , the first digital-to-analog conversion unit 112 is located on the right side of the first combining / splitting unit 111. The first combining / splitting unit 111 and the first digital-to-analog conversion unit 112 are connected, and digital signals are transmitted between the first combining / splitting unit 111 and the first digital-to-analog conversion unit 112.

[0077] The second communication module 102 includes a second combiner / splitter unit 121 and a second digital-to-analog converter 122. The second digital-to-analog converter 122 is located on one side of the second combiner / splitter unit 121. For example, in FIG5 , the second digital-to-analog converter 122 is located on the left side of the second combiner / splitter unit 121. The second combiner / splitter unit 121 and the second digital-to-analog converter 122 are connected to each other, and digital signals are transmitted between the second combiner / splitter unit 121 and the second digital-to-analog converter 122.

[0078] 5 , the first transmission direction may be a downlink direction, such as the solid arrow in FIG5 , and the second transmission direction may be an uplink direction, such as the dotted arrow in FIG5 .

[0079] In the first transmission direction (e.g., downlink direction), the first combining and splitting unit 111 combines the multi-carrier signals into one digital signal and transmits it to the first digital-to-analog conversion unit 112. The first digital-to-analog conversion unit 112 converts the digital signal received from the first combining and splitting unit 111 into an analog signal and transmits it to the second digital-to-analog conversion unit 122. The second digital-to-analog conversion unit 122 converts the analog signal received from the first digital-to-analog conversion unit 112 into a digital signal and transmits the digital signal to the second combining and splitting unit 121. The second combining and splitting unit 121 splits the one digital signal received from the second digital-to-analog conversion unit 122 into multiple multi-carrier signals.

[0080] In the second transmission direction (for example, the uplink direction), the second combining and splitting unit 121 combines the received multi-carrier signals into one digital signal and transmits it to the second digital-to-analog conversion unit 122. The second digital-to-analog conversion unit 122 converts the digital signal received from the second combining and splitting unit 121 into an analog signal and transmits it to the first digital-to-analog conversion unit 112. The first digital-to-analog conversion unit 112 converts the analog signal received by the second digital-to-analog conversion unit 122 into a digital signal and transmits it to the first combining and splitting unit 111. The first combining and splitting unit 111 splits the digital signal received from the first digital-to-analog conversion unit 112 into multiple multi-carrier signals.

[0081] In this way, the first communication module 101 and the second communication module 102 transmit signals in analog form, and the analog signal can be modulated in a high-order manner. The analog carrier signal has already been subjected to high-order modulation on the baseband side, so there is no need to perform high-order modulation again, thereby achieving a significant improvement in transmission efficiency at a low cost. Therefore, the communication system provided in the embodiment of the present application effectively improves the transmission efficiency between communication modules and significantly increases the transmission capacity of the channel, thereby meeting the transmission capacity requirements of Massive MIMO. In addition, there is no need for an additional high-order modulation, which reduces costs and avoids excessive power consumption.

[0082] It should be noted that the functions and structures of the first combining and splitting unit 111 and the second combining and splitting unit 121 can refer to the combining and splitting unit 110 in the above-mentioned communication module 100, and the functions of the first digital-to-analog conversion unit 112 and the second digital-to-analog conversion unit 122 can refer to the digital-to-analog conversion unit 120 in the above-mentioned communication module 100.

[0083] In the embodiment of the present application, when the first communication module 101 and the second communication module 102 transmit analog signals, they can be transmitted through a transmission medium, and the transmission medium can include any one of optical fiber, cable, microwave, and free space optical communication (Free Space Optical Communication, FSO).

[0084] In one possible implementation, as shown in Figure 6A, the communication system 200 can also be a base station, which can be a distributed base station or an integrated base station. In this way, the first communication module 101 can be a baseband unit, and the second communication module 102 can be a radio frequency unit. The structures of the baseband unit and the radio frequency unit can refer to the first communication module 101 and the second communication module 102 of the above embodiment. It should be noted that the structures of the first communication module 101 and the second communication module 102 can refer to the communication module 100 of the above embodiment.

[0085] In one possible implementation, as shown in FIG6B , the first combining and splitting unit 111 and the second combining and splitting unit 121 each include: a combiner 110 b and a splitter 110 a, wherein the combiner 110 b and the splitter 110 a are arranged in parallel, the combiner 110 b of the first combining unit is used to combine multi-carrier signals into one digital signal in a first transmission direction and transmit the signal to the first digital-to-analog conversion unit 112, and the splitter 110 a of the first combining unit is used to split the digital signal received from the first analog-to-digital converter 120 a into multiple multi-carrier signals in a second transmission direction. Correspondingly, the combiner 110 b of the second combining unit is used to combine multi-carrier signals into one digital signal in the second transmission direction and transmit the signal to the second digital-to-analog conversion unit 122, and the splitter 110 a of the second combining unit is used to split the digital signal received from the second analog-to-digital converter 120 a into multiple multi-carrier signals in the first transmission direction.

[0086] In one possible implementation, as shown in Figure 6B, the first digital-to-analog conversion unit 112 and the second digital-to-analog conversion unit 122 both include: an analog-to-digital converter 120a (ADC) and a digital-to-analog converter 120b (DAC), the analog-to-digital converter 120a and the digital-to-analog converter 120b are arranged in parallel, the analog-to-digital converter 120a of the first digital-to-analog conversion unit 112 is used to convert the received analog signal into a digital signal in the second transmission direction and transmit it to the splitter 110a of the first combining and splitting unit 111, and the digital-to-analog converter 120b of the first digital-to-analog conversion unit 112 is used to convert the digital signal received from the combiner 110b of the first combining and splitting unit 111 into an analog signal in the first transmission direction and send it to the digital-to-analog converter 120b of the second digital-to-analog conversion unit 122. Correspondingly, the analog-to-digital converter 120a of the second digital-to-analog conversion unit 122 is used to convert the received analog signal into a digital signal in the first transmission direction and transmit it to the splitter 110a of the second combining and splitting unit 121, and the digital-to-analog converter 120b of the second digital-to-analog conversion unit 122 is used to convert the digital signal received from the combiner 110b of the second combining and splitting unit 121 into an analog signal in the second transmission direction and send it to the analog-to-digital converter 120a of the second digital-to-analog conversion unit 122.

[0087] In one possible implementation, the first communication module 101 further includes a first correction unit 113, which is connected to the first combining / splitting unit 111. The first correction unit 113 is located on the other side of the first combining / splitting unit 111. For example, as shown in FIG6B , the first correction unit 113 is located on the left side of the first combining / splitting unit 111, and the first digital-to-analog conversion unit 112 is located on the right side of the first combining / splitting unit 111.

[0088] The second communication module 102 also includes: a second correction unit 123, the second correction unit 123 is connected to the second combining and splitting unit 121, and the second correction unit 123 is located on the other side of the second combining and splitting unit 121. For example, as shown in Figure 6B, the second correction unit 123 is located on the right side of the second combining and splitting unit 121, and the second digital-to-analog conversion unit 122 is located on the left side of the second combining and splitting unit 121.

[0089] In the first transmission direction, the first calibration unit 160 calibrates the digital signal between the first combiner / splitter unit 111 and the first digital-to-analog converter 112, so that the digital signal meets the 3GPP performance requirements. In the second transmission direction, the second calibration unit 160 calibrates the digital signal between the second combiner / splitter unit 121 and the second digital-to-analog converter 122, so that the digital signal meets the 3GPP performance requirements.

[0090] In one possible implementation, as shown in FIG6C , the second communication module 102 further includes an intermediate frequency unit 130, the intermediate frequency unit 130 being connected to the second combiner / splitter unit 121, the intermediate frequency unit 130 being located on the other side of the second combiner / splitter unit 121. For example, as shown in FIG6C , the intermediate frequency unit 130 is located on the right side of the second combiner / splitter unit 121, and digital signals are transmitted between the intermediate frequency unit 130 and the second combiner / splitter unit 121. In the first transmission direction, the multi-carrier digital signal received by the intermediate frequency unit 130 from the second combiner / splitter unit 121 can be filtered and frequency-converted to meet 3GPP performance requirements.

[0091] In the embodiment of the present application, as shown in FIG6C , in the first transmission direction, the second combiner / splitter unit 121 receives a digital signal from the second digital-to-analog conversion unit 122. Thus, the second combiner / splitter unit 121 divides the digital signal into multiple carrier signals into digital signals, so that the intermediate frequency unit 130 can filter the digital signal, and filtering the digital signal can meet the 3GPP indicator requirements for ACLR. In addition, filtering the digital signal significantly reduces the SNR (dynamic) requirement for the transmission link. Therefore, in the embodiment of the present application, the intermediate frequency unit 130 includes: a digital filter 133, the digital filter 133 is connected to the combiner / splitter unit 110, and the digital signal is transmitted between the digital filter 133 and the combiner / splitter unit 110. The digital filter 133 is used to filter the digital signal received from the combiner / splitter unit 110 and transmit it through the digital channel 134. The digital filter 133 makes the signal edge extremely steep to meet the 3GPP indicator requirements for ACLR, and significantly reduces the SNR (dynamic) requirement for the transmission link.

[0092] In one possible implementation, as shown in Figure 6C, the intermediate frequency unit 130 also includes: a digital channel 134, the digital channel 134 is connected to at least the digital filter 133, the digital signal is transmitted between the digital channel 134 and the digital filter 133, and the digital channel 134 is at least used to perform frequency conversion processing on the digital signal filtered by the digital filter 133.

[0093] As shown in FIG6C , the digital channel 134 may include a first digital channel 131 and a second digital channel 132 . The first digital channel 131 is connected to the digital filter 133 . Digital signals are transmitted between the first digital channel 131 and the digital filter 133 . The first digital channel 131 performs frequency conversion processing on the digital signal filtered by the digital filter 133 .

[0094] Among them, the second digital channel 132 is connected to the second combining and splitting unit 121. The second digital channel 132 performs frequency conversion processing on the received multi-carrier signal and sends it to the second combining and splitting unit 121 after processing. The second digital channel 132 processes the multi-carrier signal in the second transmission direction, so that the SNR of the multi-carrier signal is improved.

[0095] In a possible implementation, as shown in FIG6C , the second communication module 102 further includes a receiving unit 150 and a sending unit 140 . The receiving unit 150 can receive a multi-carrier signal, and the sending unit 140 can send the digital multi-carrier signal transmitted by the first digital channel 131 .

[0096] The application scenario of the communication system of the embodiment of the present application can be shown in Figure 7, which is a possible, non-limiting system schematic diagram. As shown in Figure 7, the communication system 200 also includes a radio access network (RAN) 201 and a core network (CN) 202. The communication system 200 may also include the Internet 203. The RAN 201 includes at least one RAN node (such as 210a and 210b in Figure 7, collectively referred to as 210) and at least one terminal (220a-220j in Figure 7, collectively referred to as 220). The RAN 201 may also include other RAN nodes, such as wireless relay devices and / or wireless backhaul devices (not shown in Figure 7). The terminal 220 is connected to the RAN node 210 via a wireless connection. The RAN node 210 is connected to the core network 202 via a wireless or wired connection. The core network equipment in the core network 202 and the RAN node 210 in the RAN 201 can be different physical devices, or they can be the same physical device that integrates the core network logical functions and the radio access network logical functions.

[0097] RAN 201 may be a cellular system related to the Third Generation Partnership Project (3GPP), such as a 4G or 5G mobile communication system, or a future-oriented evolution system (such as a 6G mobile communication system). RAN 201 may also be an open access network (O-RAN or ORAN), a cloud radio access network (CRAN), or a wireless fidelity (WiFi) system. RAN 201 may also be a communication system that integrates two or more of the above systems.

[0098] The RAN node 210, which may also sometimes be referred to as access network equipment, RAN entity or access node, etc., constitutes a part of the communication system to help terminals achieve wireless access. The multiple RAN nodes 210 in the communication system 200 may be nodes of the same type or different types. In some scenarios, the roles of the RAN node 210 and the terminal 220 are relative. For example, the network element 220i in Figure 7 may be a helicopter or a drone, which may be configured as a mobile base station. For the terminal 220j that accesses the RAN 201 through the network element 220i, the network element 220i is a base station; but for the base station 210a, the network element 220i is a terminal. The RAN node 210 and the terminal 220 are sometimes referred to as communication devices. For example, the base stations 210a and 210b in Figure 7 may be understood as communication devices with base station functions, and the network elements 220a-220j may be understood as communication devices with terminal functions.

[0099] In one possible scenario, a RAN node may be a base station, an evolved NodeB (eNodeB), an access point (AP), a transmission reception point (TRP), a next-generation NodeB (gNB), a next-generation base station in a sixth-generation (6G) mobile communication system, a base station in a future mobile communication system, or an access node in a WiFi system. A RAN node may be a macro base station (such as 210a in FIG7 ), a micro base station or an indoor station (such as 210b in FIG7 ), a relay node or a donor node, or a wireless controller in a CRAN scenario. Alternatively, a RAN node may be a server, a wearable device, a vehicle, or an onboard device. For example, the access network device in vehicle-to-everything (V2X) technology may be a roadside unit (RSU).

[0100] In another possible scenario, multiple RAN nodes collaborate to assist the terminal in achieving wireless access, with different RAN nodes implementing part of the functions of the base station. For example, the RAN node can be a centralized unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). In one implementation, the above-mentioned communication system is located in the same communication device, which is the RU. In another implementation, the RU can also be the second communication module 102. The CU and DU can be set separately, or can also be included in the same network element, such as a baseband unit (BBU) (e.g., the first communication module 101). The RU (e.g., the second communication module 102) can be included in a radio unit or in a radio unit, such as a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH).

[0101] In different systems, CU (or CU-CP and CU-UP), DU or RU may also have different names, but those skilled in the art can understand their meanings. For example, in the ORAN system, CU may also be called O-CU (Open CU), DU may also be called O-DU, CU-CP may also be called O-CU-CP, CU-UP may also be called O-CU-UP, and RU may also be called O-RU. For the convenience of description, this application uses CU, CU-CP, CU-UP, DU and RU as examples for description. Any unit of CU (or CU-CP, CU-UP), DU and RU in this application can be implemented by a software module, a hardware module, or a combination of a software module and a hardware module.

[0102] It should be understood that in this application, "electrical connection" can be understood as the physical contact and electrical conduction of components; it can also be understood as the form in which different components in the circuit structure are connected through physical lines such as printed circuit board (PCB) copper foil or wires that can transmit electrical signals. Among them, it can be understood by people in this field that. "Communication connection" can refer to electrical signal transmission, including wireless communication connection and wired communication connection. Wireless communication connection does not require a physical medium and does not belong to a connection relationship that limits the product structure. "Connection" and "connected" can both refer to a mechanical connection relationship or a physical connection relationship, that is, A is connected to B or A and B are connected, which means that there is a fastening component (such as screws, bolts, rivets, etc.) between A and B, or A and B are in contact with each other and A and B are difficult to separate.

[0103] In the description of the embodiments of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to a fixed connection or an indirect connection via an intermediate medium, internal communication between two components, or an interaction between two components. Those skilled in the art will understand the specific meanings of these terms in the embodiments of this application based on specific circumstances.

[0104] The terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of the embodiments of this application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

Claims

1. A communication module, characterized in that: include: A combining and splitting unit and a digital-to-analog conversion unit, wherein the digital-to-analog conversion unit is located on one side of the combining and splitting unit, and the combining and splitting unit is connected to the digital-to-analog conversion unit, and digital signals are transmitted between the combining and splitting unit and the digital-to-analog conversion unit; The combining and splitting unit is used to combine the multi-carrier signals into one digital signal in a first transmission direction and transmit the digital signal to the digital-to-analog conversion unit, and to split the digital signal received from the digital-to-analog conversion unit into multiple multi-carrier signals in a second transmission direction; The digital-to-analog conversion unit is used to convert the digital signal received from the combining / splitting unit into an analog signal in the first transmission direction, and to convert the received analog signal into a digital signal in the second transmission direction and transmit the digital signal to the combining / splitting unit; One of the first transmission direction and the second transmission direction is an uplink direction, and the other is a downlink direction.

2. The communication module according to claim 1, wherein: It also includes: an intermediate frequency unit, which is located on the other side of the combining and splitting unit, and is connected to the combining and splitting unit, and digital signals are transmitted between the intermediate frequency unit and the combining and splitting unit.

3. The communication module according to claim 2, wherein: The intermediate frequency unit includes: a digital filter and a digital channel; The digital filter is connected to the combining / splitting unit, and digital signals are transmitted between the digital filter and the combining / splitting unit; The digital channel is connected to the digital filter, and digital signals are transmitted between the digital channel and the digital filter; The digital channel is used to perform frequency conversion processing on the digital signal filtered by the digital filter.

4. The communication module according to any one of claims 1 to 3, characterized in that: The digital-to-analog conversion unit includes: an analog-to-digital converter and a digital-to-analog converter; The analog-to-digital converter is used to convert the received analog signal into a digital signal in the second transmission direction and transmit the digital signal to the combining and splitting unit; The digital-to-analog converter is used to convert the digital signal received from the combining / splitting unit into an analog signal in the first transmission direction.

5. The communication module according to any one of claims 1 to 4, characterized in that: The combining and splitting unit includes: a combiner and a splitter; The combiner is used to combine the multi-carrier signals into one digital signal in the first transmission direction and transmit the digital-to-analog conversion unit; The splitter is configured to split the digital signal received from the analog-to-digital converter into multiple multi-carrier signals in the second transmission direction.

6. The communication module according to any one of claims 1 to 5, characterized in that: Also includes: A correction unit is connected to the combining and splitting unit.

7. The communication module according to any one of claims 1 to 6, characterized in that: The communication module is a baseband unit.

8. The communication module according to any one of claims 1 to 6, characterized in that: The communication module is a radio frequency unit.

9. A communication system, characterized in that: include: a first communication module and a second communication module, wherein analog signals are transmitted between the first communication module and the second communication module; The first communication module includes: a first combining and splitting unit and a first digital-to-analog conversion unit, the first digital-to-analog conversion unit is located on one side of the first combining and splitting unit, the first combining and splitting unit and the first digital-to-analog conversion unit are connected, and digital signals are transmitted between the first combining and splitting unit and the first digital-to-analog conversion unit; The second communication module includes: a second combining and splitting unit and a second digital-to-analog conversion unit, the second digital-to-analog conversion unit is located on one side of the second combining and splitting unit, the second combining and splitting unit is connected to the second digital-to-analog conversion unit, and digital signals are transmitted between the second combining and splitting unit and the second digital-to-analog conversion unit; The first combining and splitting unit is configured to combine the multi-carrier signals into one digital signal in a first transmission direction and transmit the combined signal to the first digital-to-analog conversion unit, and to split the one digital signal received from the first digital-to-analog conversion unit into multiple multi-carrier signals in a second transmission direction; The first digital-to-analog conversion unit is configured to convert a digital signal received from the first combining / splitting unit into an analog signal in the first transmission direction and transmit the analog signal to the second digital-to-analog conversion unit, and to convert the analog signal received into a digital signal in the second transmission direction and transmit the analog signal to the first combining / splitting unit; The second combining and splitting unit is configured to combine the multi-carrier signals into one digital signal in the second transmission direction and transmit the combined signal to the second digital-to-analog conversion unit, and to split the one digital signal received from the second digital-to-analog conversion unit into multiple multi-carrier signals in the first transmission direction; The second digital-to-analog conversion unit is configured to convert the digital signal received from the second combining / splitting unit into an analog signal in the second transmission direction and transmit the analog signal to the first digital-to-analog conversion unit, and to convert the analog signal received in the first transmission direction into a digital signal and transmit the analog signal to the second combining / splitting unit; The first transmission direction is a downlink direction, and the second transmission direction is an uplink direction.

10. The communication system according to claim 9, wherein: The second communication module further includes an intermediate frequency unit, which is located on the other side of the second combining / splitting unit and is connected to the second combining / splitting unit, and transmits digital signals between the intermediate frequency unit and the second combining / splitting unit.

11. The communication system according to claim 10, wherein: The intermediate frequency unit includes: a digital filter and a digital channel, the digital filter is connected to the second combining and splitting unit, and digital signals are transmitted between the digital filter and the second combining and splitting unit; The digital filter is used to filter the multi-carrier signal received from the second combining and splitting unit; The digital channel is connected to the digital filter, and digital signals are transmitted between the digital channel and the digital filter; The digital channel is used to perform frequency conversion processing on the digital signal filtered by the digital filter.

12. The communication system according to claim 11, wherein: The digital channel includes: a first digital channel and a second digital channel, the first digital channel is connected to the digital filter, and digital signals are transmitted between the first digital channel and the digital filter; The second digital channel is connected to the second combining / splitting unit, and digital signals are transmitted between the second digital channel and the second combining / splitting unit.

13. The communication system according to any one of claims 9 to 12, characterized in that: The first communication module further includes: a first correction unit, which is located on the other side of the first combining / splitting unit and is connected to the first combining / splitting unit.

14. The communication system according to any one of claims 9 to 13, characterized in that: The second communication module further includes: a second correction unit, which is located on the other side of the second combining / splitting unit and is connected to the second combining / splitting unit.

15. The communication system according to any one of claims 9 to 14, characterized in that: The first communication module is a baseband unit, and the second communication module is a radio frequency unit.

16. The communication system according to any one of claims 9 to 14, characterized in that: One of the first communication module and the second communication module is a carrier chip, and the other of the first communication module and the second communication module is an intermediate frequency chip.

17. The communication system according to claim 16, wherein: The communication system is located in the same communication device, and the communication device is a radio frequency unit.

18. The communication system according to any one of claims 9 to 17, characterized in that: The analog signal is transmitted between the first communication module and the second communication module via any one of transmission media including optical fiber, cable, microwave, and free space laser communication FSO.

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