CN107534630B

CN107534630B - Signal transmission method and device

Info

Publication number: CN107534630B
Application number: CN201580079114.2A
Authority: CN
Inventors: 王珏平; 雷剑文; 蒲涛; 李兴文; 王健; 张思
Original assignee: Zhongke Xinxin Shenzhen Technology Co Ltd
Current assignee: Shenzhen Sinxin Information Technology Co ltd
Priority date: 2015-05-28
Filing date: 2015-05-28
Publication date: 2020-08-21
Anticipated expiration: 2035-05-28
Also published as: CN107534630A; WO2016187887A1

Abstract

The embodiment of the invention provides a signal transmission method and a device, wherein the method comprises the following steps: receiving N paths of common radio interface (CPRI) signals sent by first equipment, wherein the CPRI signals are obtained by encapsulating intermediate frequency signals according to a CPRI protocol, and N is an integer greater than or equal to 1; determining M paths of intermediate frequency signals according to the N paths of CPRI signals, wherein the M paths of intermediate frequency signals comprise all intermediate frequency signals extracted from the N paths of CPRI signals, and M is an integer greater than or equal to N; distributing frequency points for each path of intermediate frequency signals in the M paths of intermediate frequency signals, and modulating each path of intermediate frequency signals to the frequency points distributed for each path of intermediate frequency signals to obtain first signals, wherein the frequency points distributed for the intermediate frequency signals of different paths are different; determining a first combined signal by performing combining processing and digital-to-analog conversion processing on the M paths of first signals, wherein the first combined signal is an analog electric signal; the first combined signal is transmitted to a second device. The embodiment of the invention can effectively reduce the consumption of the transmission cable.

Description

Signal transmission method and device

Technical Field

The present invention relates to the field of communications, and in particular, to a signal transmission method and apparatus.

Background

In existing wireless cellular communication systems, distributed base stations are currently one of the most dominant deployment modalities. The distributed base station equipment is mainly divided into a Baseband processing Unit (Baseband Unit, abbreviated as "BBU") and a Remote Radio Unit (Remote Radio Unit, abbreviated as "RRU"). In the conventional technology, an RRU and a BBU generally implement transmission of Common Public Radio Interface (CPRI) signals through direct connection of cables (e.g., optical fibers or cables), for example, one RRU needs a pair of transmission optical fibers to connect to the BBU. With the increasingly diverse deployment scenarios of the distributed base stations, the transmission distance between the BBU and the RRUs of one distributed base station is increasingly long, the number of the RRUs accessing the BBU is also increasingly large, and the RRUs are also deployed in a dispersed manner in a region, so that based on the prior art, CPRI signal transmission between the RRUs and the BBU is realized, and a large amount of cable transmission resources are consumed.

Disclosure of Invention

The embodiment of the invention provides a signal transmission method and a signal transmission device, which can reduce the consumption of a transmission cable and can effectively improve the signal transmission efficiency.

A first aspect provides a signal transmission method, comprising:

receiving N paths of common radio interface (CPRI) signals sent by first equipment, wherein the CPRI signals are obtained by encapsulating intermediate frequency signals according to a CPRI protocol, and N is an integer greater than or equal to 1;

determining M paths of intermediate frequency signals according to the N paths of CPRI signals, wherein the M paths of intermediate frequency signals comprise all intermediate frequency signals extracted from the N paths of CPRI signals, and M is an integer greater than or equal to N;

distributing frequency points for each path of intermediate frequency signals in the M paths of intermediate frequency signals, and modulating each path of intermediate frequency signals to the frequency points distributed for each path of intermediate frequency signals to obtain first signals, wherein the frequency points distributed for the intermediate frequency signals of different paths are different;

determining a first combined signal by performing combining processing and digital-to-analog conversion processing on the M paths of first signals, wherein the first combined signal is an analog electric signal;

the first combined signal is transmitted to a second device.

With reference to the first aspect, in a first possible implementation manner of the first aspect, before allocating a frequency point to each of the M intermediate frequency signals, the method further includes:

determining a power constraint value and a gain adjustment coefficient of each path of intermediate frequency signal according to a signal power threshold of an analog channel and the path number M of the M paths of intermediate frequency signals, wherein the analog channel represents a channel for transmitting the first combined signal;

and adjusting the power range of each path of intermediate frequency signal according to the gain adjustment coefficient, so that the power value of each path of intermediate frequency signal after the power range adjustment does not exceed the power constraint value.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the allocating a frequency point to each of the M intermediate frequency signals includes:

performing signal sampling on each path of intermediate frequency signals by using a first rate, and performing image rejection filtering processing on each path of intermediate frequency signals obtained by sampling, wherein the first rate is the rate of the intermediate frequency signal with the maximum rate in the M paths of intermediate frequency signals;

the signal rate of each path of intermediate frequency signals after the image rejection filtering processing is improved through an interpolation technology, and the interference filtering processing is carried out on each path of intermediate frequency signals after the rate is improved;

distributing frequency points for each path of intermediate frequency signals after the interference filtering processing, and modulating each path of intermediate frequency signals to the frequency points distributed for each path of intermediate frequency signals to obtain the first signal.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in a third possible implementation manner of the first aspect, the transmitting the first combined signal to the second device includes:

converting the first combined signal into an optical signal or an electrical differential signal;

transmitting the optical signal or the electrical differential signal to the second device.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in a fourth possible implementation manner of the first aspect, M is an integer greater than N, and the method further includes:

receiving an Ethernet signal sent by third equipment;

wherein, the M intermediate frequency signals further include an intermediate frequency signal determined according to the ethernet signal.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in a fifth possible implementation manner of the first aspect, the method further includes:

receiving a second combined signal from the second device, where the second combined signal is a combined signal obtained by performing combining processing and digital-to-analog conversion processing on Q channels of second signals, where frequency points of second signals of different channels in the Q channels of second signals are different from each other, and an ith channel of second signal is a signal obtained by modulating an ith channel of intermediate frequency signal according to an ith frequency point, i is 1,2,.

Obtaining the Q-path second signal by performing shunt processing and analog-to-digital conversion processing on the second combined signal;

demodulating the ith path of second signal into the ith path of intermediate frequency signal according to the ith frequency point;

determining the P paths of CPRI signals by performing CPRI protocol encapsulation on the obtained Q paths of intermediate frequency signals;

and transmitting the P path CPRI signal to the first equipment.

With reference to the fifth possible implementation manner of the first aspect, in a sixth possible implementation manner of the first aspect, before performing CPRI protocol encapsulation on the obtained Q-path intermediate frequency signal and determining the P-path CPRI signal, the method further includes:

and performing signal rate reduction processing and interference filtering processing on each path of intermediate frequency signal.

With reference to the first aspect and the foregoing implementation manner, in a seventh possible implementation manner of the first aspect, the first device is a radio remote unit, and the second device is a baseband unit; or

The first device is a baseband unit, and the second device is a radio remote unit.

A second aspect provides a signal transmission apparatus, the apparatus comprising:

the first receiving module is used for receiving N paths of common radio interface CPRI signals sent by the first equipment, the CPRI signals are obtained by encapsulating intermediate frequency signals according to a CPRI protocol, and N is an integer greater than or equal to 1;

a first determining module, configured to determine M paths of intermediate frequency signals according to the N paths of CPRI signals received by the first receiving module, where the M paths of intermediate frequency signals include all intermediate frequency signals extracted from the N paths of CPRI signals, and M is an integer greater than or equal to N;

the modulation module is used for distributing frequency points for each path of intermediate frequency signals in the M paths of intermediate frequency signals determined by the first determination module, and modulating each path of intermediate frequency signals to the frequency points distributed for each path of intermediate frequency signals to obtain first signals, wherein the frequency points distributed for the intermediate frequency signals of different paths are different;

a combining and digital-to-analog conversion module, configured to perform combining processing and digital-to-analog conversion processing on the M channels of first signals obtained by the modulation module, and determine a first combined signal, where the first combined signal is an analog electrical signal;

and the first transmission module is used for transmitting the first combined signal obtained by the combined signal and digital-to-analog conversion module to the second device.

With reference to the second aspect, in a first possible implementation manner of the second aspect, the apparatus further includes:

a second determining module, configured to determine a power constraint value and a gain adjustment coefficient of each channel of intermediate frequency signals according to a signal power threshold of an analog channel and the number M of the M channels of intermediate frequency signals before the modulating module allocates a frequency point to each channel of intermediate frequency signals in the M channels of intermediate frequency signals, where the analog channel represents a channel for transmitting the first combined signal;

and the power adjusting module is used for adjusting the power range of each path of intermediate frequency signal according to the gain adjusting coefficient determined by the second determining module, so that the power value of each path of intermediate frequency signal after the power range adjustment does not exceed the power constraint value.

With reference to the second aspect or the first possible implementation manner of the second aspect, in a second possible implementation manner of the second aspect, the modulation module includes:

the sampling unit is used for carrying out signal sampling on each path of intermediate frequency signal by utilizing a first rate, and carrying out image rejection filtering processing on each path of intermediate frequency signal obtained by sampling, wherein the first rate is the rate of the intermediate frequency signal with the maximum rate in the M paths of intermediate frequency signals;

the signal rate increasing unit is used for increasing the signal rate of each path of intermediate frequency signals processed by the sampling unit through an interpolation technology and performing interference filtering processing on each path of intermediate frequency signals after the rate is increased;

and the modulation unit is used for distributing frequency points for each path of intermediate frequency signals processed by the signal rate increasing unit and modulating each path of intermediate frequency signals to the frequency points distributed for each path of intermediate frequency signals to obtain the first signals.

With reference to the second aspect and the foregoing implementation manner of the second aspect, in a third possible implementation manner of the second aspect, the first transmission module includes:

the conversion unit is used for converting the first combined signal into an optical signal or an electrical differential signal;

and the transmission unit is used for transmitting the optical signal or the electrical differential signal obtained by the conversion unit to the second equipment.

With reference to the second aspect and the foregoing implementation manner, in a fourth possible implementation manner of the second aspect, M is an integer greater than N, and the first receiving module is further configured to receive an ethernet signal sent by a third device;

With reference to the second aspect and the foregoing implementation manner of the second aspect, in a fifth possible implementation manner of the second aspect, the apparatus further includes:

a second receiving module, configured to receive a second combined signal from the second device, where the second combined signal is a combined signal obtained by performing combining processing and digital-to-analog conversion processing on Q channels of second signals, frequency points of second signals in different channels of the Q channels of second signals are different from each other, and an ith channel of second signal is a signal obtained by modulating an ith channel of intermediate frequency signal according to an ith frequency point, where i is 1,2,.

The branch and analog-to-digital conversion module is used for carrying out branch processing and analog-to-digital conversion processing on the second combined signal received by the second receiving module to obtain the Q paths of second signals;

the demodulation module is used for demodulating the ith path of second signal in the Q paths of second signals acquired by the shunt and analog-to-digital conversion module into the ith path of intermediate frequency signal according to the ith frequency point;

a third determining module, configured to perform CPRI protocol encapsulation on the Q-path intermediate frequency signal obtained by the demodulating module, and determine the P-path CPRI signal;

and a second transmission module, configured to transmit the P-path CPRI signal determined by the third determination module to the first device.

With reference to the fifth possible implementation manner of the second aspect, in a sixth possible implementation manner of the second aspect, the apparatus further includes:

and the signal rate reduction module is used for performing signal rate reduction processing and interference filtering processing on each path of intermediate frequency signal before the third determination module determines the P paths of CPRI signals.

With reference to the second aspect and the foregoing implementation manner, in a seventh possible implementation manner of the second aspect, the first device is a radio remote unit, and the second device is a baseband unit; or

Based on the above technical solution, in the embodiment of the present invention, for a plurality of CPRI signals that need to be transmitted from a first device to a second device, first, an intermediate frequency signal is extracted from the CPRI signal, then, different frequency points are allocated to the plurality of intermediate frequency signals, and the plurality of intermediate frequency signals are modulated onto the frequency points allocated to the plurality of intermediate frequency signals, so as to obtain corresponding first signals, then, a combination processing and a digital-to-analog conversion processing are performed on the plurality of first signals, so as to obtain a combined signal, and the combined signal is transmitted to the second device, so that the combined signal can be transmitted by using fewer transmission cables, and thus, the consumption of the transmission cables can be effectively reduced; in addition, because the intermediate frequency signal is directly transmitted, compared with the prior art in which the CPRI signal is transmitted, the signal transmission efficiency can be effectively improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor.

Fig. 1 shows a schematic diagram of an application scenario of an embodiment of the present invention.

Fig. 2 shows a schematic flow chart of a signal transmission method provided according to an embodiment of the present invention.

Fig. 3 is a schematic diagram illustrating power range adjustment of an intermediate frequency signal according to an embodiment of the present invention.

Fig. 4 is a schematic diagram illustrating frequency point modulation of multiple intermediate frequency signals according to an embodiment of the present invention.

Fig. 5 shows another schematic flow chart of a signal transmission method provided according to an embodiment of the present invention.

Fig. 6 shows a further schematic flow chart of a signal transmission method provided according to an embodiment of the present invention.

Fig. 7 shows a further schematic flow chart of a signal transmission method provided according to an embodiment of the present invention.

Fig. 8 shows a schematic block diagram of a signal transmission apparatus provided according to an embodiment of the present invention.

Fig. 9 shows another schematic block diagram of a signal transmission apparatus provided according to an embodiment of the present invention.

Fig. 10 shows still another schematic block diagram of a signal transmission apparatus provided according to an embodiment of the present invention.

Fig. 11 shows still another schematic block diagram of a signal transmission apparatus provided according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be understood that the solution of the present invention can be applied to various communication systems, such as: a Global System for Mobile communications (GSM) System, a Code Division Multiple Access (CDMA) System, a Wideband Code Division Multiple Access (WCDMA) System, a General Packet Radio Service (GPRS), a Long Term Evolution (LTE), a Frequency Division Duplex (FDD) System, a Time Division Duplex (TDD), a Universal Mobile Telecommunications System (UMTS), etc. The embodiments of the present invention will be described by taking a GSM network and an LTE network as examples, but the embodiments of the present invention are not limited thereto.

The CPRI signal mentioned in the present invention refers to an intermediate frequency signal encapsulated according to a Common Public Radio Interface (CPRI) protocol, where the intermediate frequency signal refers to a signal in an intermediate frequency band, and specifically, a signal in the intermediate frequency band that is transmitted and received in a network system such as LTE or UMTS. It should be understood that the number of paths of the intermediate frequency signals encapsulated in one path of CPRI signal is not limited to one path, for example, one path of CPRI signal may encapsulate multiple paths of intermediate frequency signals.

For ease of understanding and description, the following generally describes a signal transmission method and a signal transmission apparatus according to the present invention in conjunction with the application scenario shown in fig. 1.

As shown in fig. 1, the signal transmission apparatus 100 proposed by the present invention may be disposed between an RRU and a BBU of a station, and specifically, one signal transmission apparatus 100 (denoted as a first signal transmission apparatus 100A) is disposed on the side of the RRU, one signal transmission apparatus 100 (denoted as a second signal transmission apparatus 100B) is disposed on the side of the BBU, and a direct connection is made between the first signal transmission apparatus 100A and the second signal transmission apparatus 100B through an optical fiber or a cable. The following generally describes the whole process of signal transmission by taking the signal transmission direction as RRU to BBU as an example: the multi-channel CPRI signals sent by the RRU are converged to a first signal transmission device 100A, and the multi-channel CPRI signals are processed by the first signal transmission device 100A to obtain a combined signal; the combined signal is transmitted to a second signal transmission device 100B on the BBU side through a transmission fiber or cable; the second signal transmission device 100B recovers a plurality of CPRI signals according to the combined signal, where the plurality of CPRI signals are the plurality of CPRI signals from the RRU; the second signal transmission apparatus 100B transmits the recovered multiple CPRI signals to the BBU for processing.

It should be understood that, in fig. 1, the RRU and the first signal transmission device 100A may be directly connected through an optical fiber or a cable, the first signal transmission device 100A and the second signal transmission device 100B may also be directly connected through an optical fiber and a cable, and the second signal transmission device 100B and the BBU may be directly connected through an optical fiber or a cable.

It should also be understood that the first signal transmission device 100A and the second signal transmission device 100B shown in fig. 1 are merely for convenience of description and are not intended to limit the scope of the embodiments of the present invention. The first signal transmission device 100A and the second signal transmission device 100B are substantially the same signal transmission device.

It should be further understood that the connection lines in fig. 1 are all bidirectional, and in the signal transmission direction from the RRU to the BBU, the first signal transmission apparatus 100A receives multiple paths of CPRI signals sent by the RRU, combines the multiple paths of CPRI signals, and transmits the first combined signal obtained by the combining process to the second signal transmission apparatus 100B through an optical fiber or a cable; the first combined signal is input to the second signal transmission device 100B through an optical fiber or a cable; the second signal transmission device 100B performs splitting processing on the first combined signal, recovers the multiple CPRI signals (that is, the multiple CPRI signals acquired by the first signal transmission device 100A from the RRU), and transmits the multiple CPRI signals to the BBU for processing. In the signal transmission direction from the BBU to the RRU, the second signal transmission device 100B receives multiple paths of CPRI signals sent by the BBU, combines the multiple paths of CPRI signals, and transmits a second combined signal obtained by the combination to the first signal transmission device 100A through an optical fiber or a cable; the second combined signal is input to the first signal transmission device 100A through an optical fiber or a cable; the first signal transmission device 100A performs a splitting process on the second combined signal, recovers the multiple CPRI signals (that is, the multiple CPRI signals acquired by the second signal transmission device 100B from the BBU), and transmits the multiple CPRI signals to the RRU for processing.

In summary, in the embodiment of the present invention, the signal transmission device 100 is disposed between the RRU and the BBU, so that CPRI signal transmission between the RRU and the BBU is achieved, and a combined signal is transmitted between the first signal transmission device 100A and the second signal transmission device 100B, compared with a scheme in the prior art in which one RRU needs to connect a pair of transmission optical fibers and the BBU, consumption of the transmission optical fibers is effectively reduced.

It should be understood that the signal transmission apparatus 100 shown in fig. 1 is disposed between an RRU and a BBU, which is only a typical application scenario of the embodiment of the present invention, and the embodiment of the present invention is not limited thereto, for example, the signal transmission apparatus 100 provided according to the embodiment of the present invention may also be disposed between base stations of other sites and corresponding base station controllers.

Optionally, the signal transmission apparatus 100 provided according to the embodiment of the present invention may also be deployed between a base station of LTE and a base station controller thereof, between a base station of GSM and a base station controller thereof, or between a base station of UMTS and a base station controller thereof.

It is to be understood that S1 interface signals are transmitted between a base station of LTE and its base station controller, Abis interface signals are transmitted between a base station of GSM and its base station controller, and Iub interface signals are transmitted between a base station of UMTS and its base station controller.

Specifically, as shown in fig. 1, in the signal transmission direction from the RRU to the BBU, multiple CPRI signals from the RRU are converged to the first signal transmission apparatus 100A, and meanwhile, other ethernet signals such as an S1 interface signal of an LTE site, an Iub interface signal of a UMTS site, and an Abis interface signal of a GSM site may also be converged to the first signal transmission apparatus 100A, where the first signal transmission apparatus 100A combines the multiple CPRI signals and the multiple ethernet signals, and transmits the obtained combined signal to the second signal transmission apparatus 100B through an optical fiber or a cable; the second signal transmission device 100B receives the combined signal, and splits the combined signal to recover and obtain the multiple CPRI signals, and ethernet signals such as S1 interface signals, Iub interface signals, Abis interface signals, and the like; then, the multi-path CPRI signal is transmitted to the BBU process, and the recovered ethernet signal is transmitted to the next node, such as a core network, specifically, for example, the S1 interface signal is transmitted to the base station controller of the LTE site, the Iub interface signal is transmitted to the base station controller of the UMTS site, and the Abis interface signal is transmitted to the base station controller of the GMS site. The situation in the opposite direction is similar, and for brevity, the description is omitted here.

To sum up, the signal transmission apparatus 100 provided in the embodiment of the present invention is disposed between the signal transmitting end and the signal receiving end, and has a function of combining multiple paths of signals and a function of splitting the combined signals, specifically, when the signal transmission apparatus 100 is disposed on the transmitting end side, the combining operation is performed; when the signal transmission device 100 is disposed on the reception end side, a branching action is performed.

Hereinafter, a signal transmission method and a signal transmission apparatus according to embodiments of the present invention will be described in detail.

Fig. 2 shows a schematic block diagram of a signal transmission method 200 provided according to an embodiment of the present invention, the method 200 including:

s210, receiving N paths of common radio interface (CPRI) signals for common use sent by first equipment, wherein the CPRI signals are obtained by encapsulating intermediate frequency signals according to a CPRI protocol, and N is an integer greater than or equal to 1;

it should be understood that the CPRI signal is a digital signal, and the N-way CPRI signal may be a CPRI signal of various rates. It should also be understood that the intermediate frequency signal is the pure useful signal in the CPRI signal, which contains the pure useful data.

S220, determining M paths of intermediate frequency signals according to the N paths of CPRI signals, wherein the M paths of intermediate frequency signals comprise all intermediate frequency signals extracted from the N paths of CPRI signals, and M is an integer greater than or equal to N;

specifically, the CPRI de-framing processing is performed on the CPRI signal to obtain an intermediate frequency signal. It should be understood that performing CPRI de-framing on the CPRI signal to obtain the intermediate frequency signal is prior art and will not be described herein.

It should also be understood that one CPRI signal may encapsulate multiple intermediate frequency signals, for example, one CPRI signal is obtained by performing CPRI protocol encapsulation on 4 paths of intermediate frequency signals, and therefore, performing CPRI deframing on the CPRI signal may extract 4 paths of intermediate frequency signals. It should also be understood that the paths of the intermediate frequency signals encapsulated by the CPRI signals of different paths may also be different, and therefore, the paths of the intermediate frequency signals extracted from the CPRI signals of different paths are also different. Therefore, in the embodiment of the present invention, M intermediate frequency signals can be extracted from N CPRI signals, where M is greater than or equal to N.

S230, distributing frequency points for each path of intermediate frequency signals in the M paths of intermediate frequency signals, and modulating each path of intermediate frequency signals to the frequency points distributed for each path of intermediate frequency signals to obtain first signals, wherein the frequency points distributed for the intermediate frequency signals of different paths are different;

specifically, each path of intermediate frequency signal is moved to a frequency point allocated to the intermediate frequency signal, and a first signal corresponding to each path of intermediate frequency signal is obtained. Through the steps, M paths of first signals are obtained. It should be understood that the first signal is a digital signal.

S240, determining a first combined signal by combining and digital-to-analog conversion processing the M paths of first signals, wherein the first combined signal is an analog electric signal;

it should be understood that the first combined signal is an analog electrical signal including only one signal.

And S250, transmitting the first combined signal to the second device.

Optionally, in the embodiment of the present invention, the first device is a radio remote unit RRU, and the second device is a baseband unit BBU; or

The first device is a baseband unit BBU, and the second device is a radio remote unit RRU.

Specifically, for example, the first device is, for example, N RRUs, and the second device is one BBU; or the first device is a BBU, and the second device is N RRUs.

For example, in the scenario shown in fig. 1, when the first device is a radio remote unit RRU and the second device is a baseband unit BBU, an implementation subject of the embodiment of the present invention may be the first signal transmission apparatus 100A shown in fig. 1; when the first device is a baseband unit BBU and the second device is a radio remote unit RRU, the executing body of the embodiment of the present invention may be the second signal transmission apparatus 100B shown in fig. 1.

It should be understood that, in the embodiment of the present invention, by combining multiple paths of signals and finally transmitting a combined signal, compared to the prior art in which one RRU needs a pair of transmission fibers and a BBU to perform CPRI signal transmission, the consumption of transmission cables can be effectively reduced.

It should also be understood that the data amount of the intermediate frequency signal is small relative to the CPRI signal, for example, for a 20M LTE intermediate frequency signal received and transmitted in 2-transmission mode and 2-reception mode, the CPRI signal obtained after being encapsulated according to the CPRI protocol can reach 2.5Gbps, and therefore, compared with the CPRI signal, the efficiency of signal transmission can be effectively improved by directly transmitting the intermediate frequency signal. In the implementation of the invention, the intermediate frequency signal is extracted from the CPRI signal, and then the subsequent combination processing and digital-to-analog conversion processing are carried out on the multi-channel intermediate frequency signal, so that the combination signal in the analog domain is obtained for transmission, and the signal transmission efficiency can be effectively improved.

Therefore, in the embodiment of the present invention, for a plurality of CPRI signals that need to be transmitted from a first device to a second device, first, an intermediate frequency signal is extracted from the CPRI signal, then, different frequency points are allocated to the plurality of intermediate frequency signals, and the plurality of intermediate frequency signals are modulated onto the frequency points allocated to the plurality of intermediate frequency signals, so as to obtain corresponding first signals, then, a combination processing and a digital-to-analog conversion processing are performed on the plurality of first signals, so as to obtain a combination signal, and the combination signal is transmitted to the second device, so that the combination signal can be transmitted by using fewer transmission cables, and thus, the consumption of the transmission cables can be effectively reduced; in addition, because the intermediate frequency signal is directly transmitted, compared with the prior art in which the CPRI signal is transmitted, the signal transmission efficiency can be effectively improved.

It should be understood that, in S210, N paths sent by the first device are received by using the common radio interface CPRI, where N may be 1, for example, when data sent by a single RRU is large, assuming that 1 path of CPRI signals sent by the single RRU encapsulates 16 paths of intermediate frequency signals, even 64 paths of intermediate frequency signals, and the 1 path of CPRI is to be transmitted to the BBU side, the signal transmission method and the signal transmission apparatus provided in the embodiments of the present invention may also be used in this scenario, where the signal transmission apparatus provided in the embodiments of the present invention serves as a data transmission apparatus.

Specifically, in S220, an intermediate frequency signal is extracted from the CPRI signal, where the intermediate frequency signal may be a signal of various network systems, for example, an intermediate frequency signal of an LTE system, or an intermediate frequency signal of other systems such as UMTS, and the intermediate frequency signals all have a certain peak-to-average ratio, and it should be understood that the peak-to-average ratio of the signal refers to a measurement parameter of a waveform, and is equal to a ratio obtained by dividing an amplitude of the waveform by an effective value (RMS), and may also be understood as a ratio of an instantaneous peak power of the signal to an average power of the signal within a certain period of time, and represents the power of the signal as a whole.

It should also be understood that when multiple signals are combined, the greater the number of signals combined, the greater the peak-to-average ratio of the signals after combination, i.e., the greater the signal power, and vice versa. In the embodiment of the present invention, considering that the signal power of the M channels of intermediate frequency signals after being combined may be very large, and further may exceed the signal power threshold of the analog channel, which may cause signal distortion, the power range of the M channels of intermediate frequency signals is adjusted first. The analog channel represents a transmission channel of an analog signal, and in the embodiment of the present invention, specifically refers to an analog channel that transmits the first combined signal. The signal power threshold of the analog channel refers to the maximum signal power value allowed by the analog channel to transmit signals, and if the power value of the signals transmitted in the analog channel exceeds the signal power threshold, the linearity performance of the analog channel is affected, that is, problems such as signal distortion are generated.

Optionally, in this embodiment of the present invention, before allocating a frequency point to each of the M intermediate frequency signals in S230, the method 200 further includes:

s260, determining a power constraint value and a gain adjustment coefficient of each path of intermediate frequency signal according to a signal power threshold of an analog channel and the path number M of the M paths of intermediate frequency signals, wherein the analog channel represents a channel for transmitting the first combined signal;

and S270, performing power range adjustment on each path of intermediate frequency signal according to the gain adjustment coefficient, so that the power value of each path of intermediate frequency signal after the power range adjustment does not exceed the power constraint value.

Specifically, in S260, 1) determining a power constraint value of each channel of the intermediate frequency signal according to a signal power threshold of the analog channel and the number M of channels of the M channels of intermediate frequency signals; 2) and determining the gain adjustment coefficient of each intermediate frequency signal by comparing the measured power of each intermediate frequency signal with the power constraint value of each intermediate frequency signal.

In 1), determining a power constraint value of each path of intermediate frequency signal according to a signal power threshold of an analog channel and the number M of paths of the M paths of intermediate frequency signals, specifically, determining a peak-to-average ratio Px of the M paths of intermediate frequency signals after combination according to the number M; then, according to the signal power threshold Pmax of the analog channel and the peak-to-average ratio Px, the power constraint value Ps of the intermediate frequency signal in each channel is determined.

Specifically, assume that the signal power threshold of the analog channel is Pmax, i.e., the maximum signal power allowed for the analog channel is Pmax. Assuming that the number of the intermediate frequency signals converged to the analog channel is 24, and determining that the peak-to-average ratio after the 24 intermediate frequency signals are combined is Px, the maximum power Ps of each intermediate frequency signal after the 24 intermediate frequency signals are converged to the analog channel is allowed to be (Pmax-Px)/24, that is, the power constraint value of each intermediate frequency signal is Ps.

Based on the information shown in table 1, the peak-to-average ratio Px of the M intermediate frequency signals after combining may be determined according to the number M of channels. Specifically, the corresponding relationship between the number of intermediate frequency signals combined and the peak-to-average ratio of the combined signals is stored in a table form, and as shown in table 1, the number of combined paths is divided into three stages: the peak-to-average ratio of the combined signals of 1-16 paths is uniformly determined as the peak-to-average ratio after the combination of the intermediate frequency signals of 16 paths, namely as long as the number of the paths of the combined intermediate frequency signals is within 16 paths, the peak-to-average ratio after the combination is uniformly determined as P1; uniformly determining the peak-to-average ratio of the combined signals of 16-32 paths as the peak-to-average ratio P2 after the combination of the intermediate frequency signals of 32 paths; and uniformly determining the peak-to-average ratio of the combined signals of 33-48 paths as the peak-to-average ratio P3 after the intermediate frequency signals of 48 paths are combined. The peak-to-average ratio information P1 after the combination of 16 intermediate frequency signals, the peak-to-average ratio information P2 after the combination of 32 intermediate frequency signals, and the peak-to-average ratio information P3 after the combination of 48 intermediate frequency signals can be obtained by means of actual measurement or simulation.

TABLE 1

Number of combining paths	Peak to average ratio
		1～16	P1
17～32	P2
		33～48	P3

In the above example of 24 intermediate frequency signals, if the peak-to-average ratio Px after the combination of the 24 intermediate frequency signals falls in the second gear shown in table 1, i.e., if the peak-to-average ratio Px after the combination of the 24 intermediate frequency signals is considered to be P2, the maximum power Ps of each intermediate frequency signal is allowed to be (Pmax-P2)/24.

It should be understood that table 1 schematically shows peak-to-average ratios of intermediate frequency signals of different paths after combining, specifically, three stages are divided, in practical application, more stages may be divided, and this is not limited in the embodiment of the present invention. It will be appreciated that the division into more stages results in more accurate results, but correspondingly the processing is more complex, so that various tradeoffs are required in implementation.

In the above-described method, the power constraint values of each of the plurality of intermediate frequency signals are the same, and it should be understood that the embodiments of the present invention are not limited thereto. In practical application, the power constraint values of the intermediate frequency signals in different paths can be determined respectively, as long as the sum of the power constraint values of all the intermediate frequency signals is ensured not to exceed the difference between the signal power threshold of the analog channel and the peak-to-average ratio Px of the multiple paths of intermediate frequency signals after being combined.

In 2), the gain adjustment coefficient of each intermediate frequency signal is determined by comparing the measured power of each intermediate frequency signal with the power constraint value thereof, specifically, taking a single-channel intermediate frequency signal x as an example for description, when the measured power of the intermediate frequency signal x is less than or equal to the power constraint value of the intermediate frequency signal x, the gain adjustment coefficient of the intermediate frequency signal x may be 1; when the measured power of the intermediate frequency signal x is greater than the power constraint value of the intermediate frequency signal x, the gain adjustment coefficient of the intermediate frequency signal x is less than 1, and the product of the measured power of the intermediate frequency signal x and the gain adjustment coefficient does not exceed the power constraint value of the intermediate frequency signal x.

In S270, according to the gain adjustment coefficient, performing power range adjustment on each path of the intermediate frequency signal, so that the power value of each path of the intermediate frequency signal after the power range adjustment does not exceed the power constraint value. In particular, fig. 3 shows a schematic block diagram of power range adjustment for each if signal provided according to an embodiment of the present invention. For convenience of description and understanding, the following description will be given by taking a single-channel if signal x as an example, first, a power meter measures the power of the if signal x (i.e. the measured power of the if signal x); then comparing the actual measurement power of the intermediate frequency signal x with the power constraint value thereof through a comparator, and further determining a gain adjustment coefficient of the intermediate frequency signal x; finally, the gain adjustment coefficient is used to adjust the power range of the intermediate frequency signal x, specifically, the signal power range of the intermediate frequency signal x is adjusted by multiplying the gain adjustment coefficient by the intermediate frequency signal x.

In the embodiment of the invention, the signal power of each path of intermediate frequency signal is adjusted according to the path number of the actually transmitted intermediate frequency signal, so that the signal power of the combined signal of the M paths of signals after combination is in the linear range of the analog channel.

It should be understood that, for each of the M intermediate frequency signals obtained in S220, the power range adjustment is performed according to the method described in S260 and S270 above.

In S230, a frequency point is allocated to each of the M channels of intermediate frequency signals, and each channel of intermediate frequency signal is modulated to the frequency point allocated to each channel of intermediate frequency signal, so as to obtain a first signal, where the frequency points allocated to different channels of intermediate frequency signals are all different.

Specifically, fig. 4 shows a schematic diagram of allocating frequency points for multiple intermediate frequency signals according to an embodiment of the present invention. In the spectrum f of the whole analog channel, a frequency point fn is allocated to each channel of intermediate frequency signals, for example, a frequency point f1 is allocated to the 1 st channel of intermediate frequency signals in M channels, a frequency point f2 is allocated to the 2 nd channel of intermediate frequency signals, and so on, where the analog channel refers to a channel for transmitting analog signals, and in the embodiment of the present invention, specifically, refers to a channel for transmitting first combined signals. Specifically, frequency points may be allocated to each channel of intermediate frequency signals according to preset information, or frequency points may be allocated randomly, but each channel of intermediate frequency signals corresponds to the frequency points allocated to each channel of intermediate frequency signals one to one, in other words, the frequency points allocated to different channels of intermediate frequency signals are different.

Specifically, there is a certain interval between the frequency points allocated to different paths of intermediate frequency signals, and the size of the interval may be determined by the spectrum width of each path of intermediate frequency signal, for example, the spectrum width of an intermediate frequency signal of LTE is 20M, so that the interval between the frequency point of the radio frequency signal and the frequency points of other signals needs 20M.

The respective spectrum widths of different paths of intermediate frequency signals may be different, and correspondingly, the adjacent intervals of the frequency points of different paths of intermediate frequency signals are also different. Optionally, for simple design, adjacent intervals of frequency points of different paths of intermediate frequency signals may be equal, and the inter-frequency point width is determined according to the frequency spectrum width of the intermediate frequency signal with the widest signal frequency spectrum width.

After distributing the frequency point for every way intermediate frequency signal, modulate every way intermediate frequency signal respectively for its distributed frequency point on, can understand to move the intermediate frequency signal to the frequency point that corresponds by the intermediate frequency at its place itself on, as shown in fig. 4, move the 1 st way intermediate frequency signal to frequency point f1 on, move the 2 nd way intermediate frequency signal to frequency point f2 on, move the ith way intermediate frequency signal to frequency point fi on, i is 1, 2. It should be understood that, the 1 st path intermediate frequency signal is modulated according to the frequency point f1, so as to obtain a 1 st path first signal; modulating the 2 nd path intermediate frequency signal according to a frequency point f2 to obtain a 2 nd path first signal; and modulating the ith path of intermediate frequency signal according to the frequency point fi to obtain an ith path of first signal, wherein i is 1, 2. That is, in S230, M channels of first signals are obtained, and the frequency points of the first signals of different channels are different from each other.

Optionally, in this embodiment of the present invention, the allocating a frequency point to each of the M intermediate frequency signals in S230 includes:

s231, performing signal sampling on each path of intermediate frequency signal by using a first rate, and performing image rejection filtering processing on each path of intermediate frequency signal obtained by sampling, wherein the first rate is the rate of the intermediate frequency signal with the maximum rate in the M paths of intermediate frequency signals;

specifically, the signal rates of the intermediate frequency signals of different paths may be different, and in the embodiment of the present invention, the sampling rate of the highest rate signal is uniformly adopted for the intermediate frequency signals of different rates for sampling. In this way, an image signal is generated for an intermediate frequency signal with a low rate, and in the embodiment of the present invention, the generated image signal is suppressed by using an image suppression filter, wherein the order and the coefficient of the image suppression filter are determined according to actual design requirements, which is not limited in this patent.

In a signal acquisition method in the conventional technology, a signal rate is increased step by step according to a signal rate, so that the lower the signal rate is, the larger the time delay is. In the embodiment of the invention, the signal sampling is carried out on each path of intermediate frequency signals by adopting the rate of the intermediate frequency signal with the maximum rate in the M paths of intermediate frequency signals, and the generated image signal is inhibited by adopting the image inhibiting technology, so that the transmission delay of the low-rate signal is effectively reduced compared with the traditional technology.

Therefore, in the embodiment of the invention, the intermediate frequency signals with different bandwidths are sampled by adopting the same sampling rate, and the processing of the image rejection filter is added, so that the processing time delay of the narrow-band intermediate frequency signal is the same as that of the wide-band intermediate frequency signal, and the overall transmission time delay of the M paths of intermediate frequency signals can be reduced.

S232, the signal rate of each path of intermediate frequency signals after the image rejection filtering processing is promoted through an interpolation technology, and the interference filtering processing is carried out on each path of intermediate frequency signals after the rate promotion;

specifically, for each channel of intermediate frequency signals obtained through the processing in S231, an interpolation technique is used to increase the signal rate. It should be understood that, when the interpolation technique is used to increase the signal rate, harmonics are generated, and therefore, the harmonics need to be filtered, so as to eliminate the interference generated when the interpolation technique is used to increase the rate, in the embodiment of the present invention, the intermediate frequency signal processed by the interpolation technique is filtered.

In the embodiment of the invention, the signal rate of the intermediate frequency signal is effectively improved by adopting the interpolation technology, and the interference of harmonic waves generated by the interpolation technology on each path of intermediate frequency signal is eliminated by utilizing the filtering technology.

S233, allocating a frequency point to each path of the intermediate frequency signal after the interference filtering processing, and modulating each path of the intermediate frequency signal to the frequency point allocated to each path of the intermediate frequency signal to obtain the first signal.

For allocating frequency points to each channel of intermediate frequency signals after being processed in S231 and S232, please refer to the description in S230 above for specific steps, and details are not described here for brevity.

In S240, the first combined signal is determined by performing combining processing and digital-to-analog conversion processing on the M channels of first signals.

It should be understood that combining the M first signals refers to combining the M first signals into one signal, and the combining process includes combining digital signals and/or combining analog signals. Specifically, the combining process may be performed on the M channels of first signals, that is, the digital signals are combined, and then digital-to-analog conversion (hereinafter referred to as D/a conversion) is performed to obtain the first combined signal (analog signal); or D/a conversion may be performed on the M first signals respectively to obtain M analog signals, and then the M analog signals are combined, which is equivalent to combining the analog signals, so as to finally obtain the first combined signal.

Optionally, in this embodiment of the present invention, the determining, by performing combining processing and digital-to-analog conversion processing on the M channels of first signals, a first combined signal in S240 includes:

performing digital signal combining processing on the M paths of first signals to obtain a combined signal C2, where the combined signal C2 is a digital signal;

d/a conversion is performed on the combined signal C2 to determine the first combined signal.

Specifically, the digital signal combining processing is performed on the M first signals, assuming that the combined signal obtained after the digital signal combining processing is performed on the M first signals is C2, then the D/a conversion is performed on the combined signal C2, so as to obtain the first combined signal in the analog domain. It should be understood that, it is also possible to combine digital signals of a part of the M first signals, then perform D/a conversion on the multiple combined signals, and then perform analog signal combining on the multiple analog signals to obtain the first combined signal. For example, assuming that there are 5 first signals in total, digital signal combining processing is performed on 3 first signals to obtain a combined signal C3, digital signal combining processing is performed on the remaining 2 first signals to obtain a combined signal C4, D/a conversion is performed on the combined signal C3 and the combined signal C4 respectively to obtain a combined signal C3 'and a combined signal C4' in an analog domain, and finally analog signal combining processing is performed on the combined signal C3 'and the combined signal C4', and finally the first combined signal is obtained.

D/A conversion is carried out on each path of first signals in the M paths of first signals to obtain corresponding first analog signals;

and carrying out analog signal combination processing on the M paths of first analog signals to obtain the first combined signal.

Specifically, each of the M first signals may be subjected to D/a conversion to finally obtain M analog signals, and it should be understood that frequency points of different analog signals in the M analog signals are different, and then the M analog signals are subjected to analog signal combining processing to obtain the first combined signal in the analog domain.

It should be understood that the signal combining and digital-to-analog conversion (DAC) involved in the embodiments of the present invention are prior art, and are not described herein again for brevity.

In S250, the first combined signal obtained through the processing in S210 to S240 is transmitted to the second device. It should be understood that the first combined signal is an analog electrical signal, and may be converted into an optical signal and transmitted to the second device side by using light, or may be converted into an electrical differential signal and transmitted to the second device side by using a cable, which is not limited in this embodiment of the present invention.

Optionally, in this embodiment of the present invention, the transmitting, S250, the first combined signal to the second device includes:

s261, converting the first combined signal into an optical signal or an electrical differential signal;

s262, transmitting the optical signal or the electrical differential signal to the second device.

To sum up, in the embodiment of the present invention, in the process of transmitting multiple CPRI signals from the first device to the second device, the intermediate frequency signal is extracted from the CPRI signal, then a frequency point is allocated to the multiple intermediate frequency signals, and frequency point modulation processing, combining processing, and digital-to-analog conversion processing are performed to obtain a combined signal in an analog domain, and finally the combined signal is transmitted to the second device through an optical fiber or a cable. In other words, in the embodiment of the present invention, multiple digital signals are converted into one analog signal and transmitted over an optical fiber or a cable.

Therefore, according to the signal transmission method provided by the embodiment of the invention, compared with the existing optical fiber direct connection technology, the consumption of a transmission cable (optical fiber or cable) is effectively reduced; compared with the prior art in which CPRI signals are transmitted transparently, the embodiment of the invention can effectively improve the signal transmission efficiency; according to the number of the paths of the actually transmitted intermediate frequency signals, the signal power of each path of intermediate frequency signals is adjusted to adjust the dynamic range of the intermediate frequency signals, so that better analog channel linearity performance is obtained, and the reliability of signal transmission is improved.

It should be noted that, in the embodiment of the present invention, before combining multiple channels of signals, different channels of signals are modulated onto different frequency points, so that after combining, the signals in different channels can be accurately recovered from the combined signals according to the corresponding relationship between the different channels of signals and their respective frequency points. This will be described in detail below.

Optionally, as shown in fig. 5, in the embodiment of the present invention, the method 200 further includes:

s310, receiving a second combined signal from the second device, where the second combined signal is a combined signal obtained by performing combining processing and digital-to-analog conversion processing on Q channels of second signals, where frequency points of different channels of second signals in the Q channels of second signals are different from each other, and an ith channel of second signal is a signal obtained by modulating an ith channel of intermediate frequency signal according to an ith frequency point, i is 1,2,.

Specifically, assuming that the first device in the embodiment of the present invention is an RRU and the second device is a BBU, for example, an execution subject of the embodiment of the present invention is a first signal transmission apparatus 100A shown in fig. 1, and assuming that the second combined signal received in S310 is a combined signal obtained by processing a P-way CPRI signal sent by a BBU by a second signal transmission apparatus 100B disposed on the BBU side shown in fig. 1, where a specific processing procedure 400 of the P-way CPRI signal from the BBU by the second signal transmission apparatus 100B may be similar to that of S210 to S280 described above, and specifically as follows:

s410, the second signal transmission apparatus 100B receives the P-path CPRI signal sent by the BBU (corresponding to the second device);

s420, the second signal transmission apparatus 100B determines Q paths of intermediate frequency signals according to the P paths of CPRI signals, where the Q paths of intermediate frequency signals include all intermediate frequency signals extracted from the P paths of CPRI signals, and Q is an integer greater than or equal to P;

specifically, CPRI de-framing is performed on the P-channel CPRI signal to obtain Q-channel intermediate frequency signals.

S430, the second signal transmission device 100B allocates frequency points for each channel of the Q channels of intermediate frequency signals, and modulates each channel of intermediate frequency signals to the frequency points allocated for each channel of intermediate frequency signals to obtain second signals, where the frequency points allocated for different channels of intermediate frequency signals are all different;

specifically, a frequency point f1 is allocated to the 1 st intermediate frequency signal in the Q paths of intermediate frequency signals, and the 1 st intermediate frequency signal is modulated to a frequency point f1, so as to obtain a 1 st second signal; and distributing a frequency point f2 for the 2 nd path intermediate frequency signal in the Q paths of intermediate frequency signals, modulating the 2 nd path intermediate frequency signal to a frequency point f2 to obtain a 2 nd path second signal, and so on.

S440, determining a second combined signal by performing combining processing and digital-to-analog conversion processing on the Q-path second signal, wherein the second combined signal is an analog electric signal;

s450, the second signal transmission apparatus 100B transmits the second combined signal to an RRU (corresponding to the first device).

The detailed steps are similar to those described in S210 to S280 above, and are not described herein again for brevity.

It should be understood that the second combined signal received from the second device (BBU) in S310 is the combined signal obtained by the second signal transmission apparatus 100B performing the processing from S410 to S450 on the P-channel CPRI signal from the BBU.

S320, obtaining the Q-path second signal by carrying out shunt processing and analog-to-digital conversion processing on the second combined signal;

specifically, the second combined signal may be first subjected to splitting processing to obtain Q-path analog signals, and then each path of analog signals is subjected to a/D conversion to obtain Q-path second signals; or the second combined signal may be first subjected to a/D conversion to obtain a corresponding digital combined signal, and then the digital combined signal is shunted to obtain the Q-path second signal.

It should be understood that the Q second signals in S230 correspond to the Q second signals in S430.

S330, demodulating the ith path of second signal into the ith path of intermediate frequency signal according to the ith frequency point;

it should be understood that, for example, the 1 st channel intermediate frequency signal is modulated according to the frequency point f1, so as to obtain a 1 st channel first signal; and demodulating the 1 st path first signal according to the frequency point f1, so as to recover and obtain the 1 st path intermediate frequency signal.

Modulating each of the Q paths of second signals to the original intermediate frequency by a respective frequency point, specifically, demodulating the 1 st path of second signal according to a frequency point f1 (it should be understood that the 1 st path of second signal is obtained by modulating the 1 st path of intermediate frequency signal according to the frequency point f1, see S430 for details), and obtaining the 1 st path of intermediate frequency signal; demodulating the 2 nd path second signal according to a frequency point f2 (it should be understood that the 2 nd path second signal is obtained by modulating the 2 nd path intermediate frequency signal according to the frequency point f 2), so as to obtain a 2 nd path intermediate frequency signal; and by parity of reasoning, Q paths of intermediate frequency signals are obtained. It should be understood that the Q if signal corresponds to the Q if signal determined in S430.

It should be understood that the process of the first signal transmission device 100A moving the second signal back to the intermediate frequency to obtain the intermediate frequency signal and the process of the second signal transmission device 100B moving the intermediate frequency signal to the specific frequency point allocated to it to obtain the second signal are two opposite processes.

S340, performing CPRI protocol encapsulation on the obtained Q-path intermediate frequency signal to determine the P-path CPRI signal;

specifically, CPRI framing is performed on the Q-path intermediate frequency signal. This technique is prior art and will not be described in detail here.

It should be understood that, if, in the second combined signal obtaining process, the 1 st and 2 nd intermediate frequency signals in the Q-path intermediate frequency signals are extracted from the same CPRI signal (i.e., the 1 st CPRI signal), in this step, the 1 st and 2 nd intermediate frequency signals in the Q-path intermediate frequency signals are also packaged together into one CPRI signal, i.e., the 1 st CPRI signal. That is, the CPRI framing processing in S340 and the deframing processing in S420 correspond to each other.

And S350, transmitting the P-path CPRI signal to the first equipment.

It should be understood that the P-way CPRI signal transmitted to the first device (RRU) is the P-way CPRI signal received by the second signal transmission apparatus 100B from the second device (BBU) in S410.

In the embodiment of the invention, the combined signal from the second device is received, the combined signal is subjected to the shunting processing and the analog-to-digital conversion processing, and the CPRI framing processing to obtain the multi-path CPRI signal and is transmitted to the first device, so that the CPRI signal is transmitted from the second device to the first device. In addition, in the embodiment of the invention, before the CPRI framing, the intermediate frequency signal which is not encapsulated by the CPRI protocol is directly transmitted, so that the signal transmission efficiency can be effectively improved.

It should be understood that, in the embodiment of the present invention, the second combined signal received in S310 may be an analog electrical signal converted from an optical signal transmitted by an optical fiber between the first signal transmission device 100A and the second signal transmission device 100B, or an analog electrical signal converted from an electrical differential signal transmitted by a cable between the first signal transmission device 100A and the second signal transmission device 100B.

Optionally, in this embodiment of the present invention, before determining the P-channel CPRI signal by performing CPRI protocol encapsulation on the obtained Q-channel intermediate frequency signal in S340, the method further includes:

and S360, performing signal rate reduction processing and interference filtering processing on each path of intermediate frequency signal.

Specifically, the signal rate is reduced by a decimation technique, and interference caused by the decimation technique is filtered out by a filtering technique.

Therefore, in the embodiment of the present invention, the received combined signal is subjected to a splitting process, an analog-to-digital conversion process, and a CPRI framing process, so as to finally obtain a plurality of CPRI signals, which are transmitted to the RRU for processing, thereby reducing the consumption of the transmission cable, and improving the signal transmission efficiency.

As mentioned above, the signal transmission method and the signal transmission apparatus in the embodiments of the present invention are not limited to be applied to the CPRI signal transmission process between the RRU and the BBU, but can also be applied to the signal transmission process between other ethernet elements.

In S220, M paths of intermediate frequency signals are determined according to the N paths of CPRI signals, and specifically, the M paths of intermediate frequency signals are determined according to the N paths of CPRI signals and the ethernet signal, where the M paths of intermediate frequency signals include all CPRI signals extracted from the N paths of CPRI signals and intermediate frequency signals determined according to the ethernet signal.

Optionally, in this embodiment of the present invention, M is an integer greater than N, and the method 200 further includes:

s280, receiving an Ethernet signal sent by third equipment;

As shown in fig. 1, the ethernet signal is, for example, an S1 interface signal from an LTE site, an Abis interface signal from a GSM site, or an Iub interface signal from a UMTS site or other ethernet interface signals.

Optionally, in this embodiment of the present invention, the step S220 of determining M paths of intermediate frequency signals according to the N paths of CPRI signals includes:

s221, performing CPRI deframing processing on the N paths of CPRI signals to obtain M1 paths of intermediate frequency signals;

s222, modulating the Ethernet signal to obtain an M2 intermediate frequency signal;

and S233, determining the M intermediate frequency signals according to the M1 intermediate frequency signals and the M2 intermediate frequency signals, wherein M is the sum of M1 and M2.

Specifically, the ethernet signal (e.g., S1 interface signal, Abis interface signal, Iub interface signal, or other ethernet signal) is subjected to a shaping filtering and modulation. The modulation mode can select QAM modulation or other modulation modes according to requirements. If the reliability of transmission is to be increased, channel coding, such as FEC coding, can be added before the shaping filtering and modulation.

Therefore, the signal transmission method provided by the embodiment of the invention supports the transmission of signals such as a CPRI protocol signal, an S1 interface signal and the like, and has a wider application range.

Fig. 6 shows a schematic flow chart of a signal transmission method 500 provided according to an embodiment of the present invention, where an execution subject of the method 500 is, for example, the first signal transmission apparatus 100A shown in fig. 1, and for convenience of description, a signal transmission scenario shown in fig. 6 is defined as: and transmitting the 3 paths of CPRI signals sent by the RRU to the BBU, and transmitting the Ethernet signals (including signals of Ethernet data) of other network elements (such as an LTE base station, a UMTS base station or a GSM base station) to a next node, such as a core network. As shown in fig. 6, the method 500 includes:

s510, performing CPRI deframing on 3 paths of CPRI signals sent by the RRU respectively to obtain 3 paths of intermediate frequency signals;

s520, adjusting the signal power range of each path of intermediate frequency signal in the 3 paths of intermediate frequency signals obtained in the S510;

for details, please refer to S270 and S280 above, which are not described herein.

S530, for each path of signals in the intermediate frequency signal and the ethernet signal processed in S520, performing signal sampling at a first rate, and performing image rejection filtering, where the first rate is the rate of the signal with the highest rate in all the signals acquired in S530;

for a detailed description, please refer to the description of S231 above, which is not repeated here.

It should be understood that before the operation of S530 is performed on the ethernet signal, S590 is also included, and the quadrature signal is shaped, filtered and modulated. Specifically, the modulation scheme may be QAM modulation or another modulation scheme as needed. If the reliability of transmission is to be increased, channel coding, such as FEC coding, can be added before the shaping filtering and modulation.

And S540, aiming at the signal processed in the S530, increasing the signal rate by adopting an interpolation technology. To eliminate the interference caused when the rate is raised by the interpolation technique, the intermediate frequency signal processed by the interpolation technique is filtered.

It should be understood that the steps S510 to S540 are performed for each signal (including the CPRI signal and the ethernet signal), that is, the operations of the steps S510 to S540 are performed for each signal to be combined.

S550, performing frequency mixing processing on the signals processed in the S540, and modulating multiple paths of signals to different frequency points respectively;

specifically, suppose that 4 channels of signals (3 channels of intermediate frequency signals and 1 channel of ethernet signals) need to be mixed, for example, different frequency points are allocated to the 4 channels of signals, for example, a frequency point f1 is allocated to the 1 channel of intermediate frequency signals, a frequency point f2 is allocated to the 2 channels of intermediate frequency signals, a frequency point f3 is allocated to the 3 channels of intermediate frequency signals, and a frequency point f4 is allocated to the ethernet signals, as shown in the schematic diagram shown in fig. 4. Then, for example, a mixer modulates the 1-channel intermediate frequency signal to f1, and the obtained signal at frequency point f1 is referred to as a 1-channel first signal. It should be understood that, according to the prior art, the local oscillator of the mixer may be configured to the frequency point f1, so that the 1-channel intermediate frequency signal may be modulated onto the frequency point f1, which is the prior art and detailed description of the specific implementation process is omitted. And modulating the 2 paths of intermediate frequency signals to f2 by using a mixer in sequence to obtain 2 paths of first signals, modulating the 3 paths of intermediate frequency signals to f3 to obtain 3 paths of first signals, and modulating the Ethernet signals to f4 to obtain 4 paths of first signals. It should be understood that the frequency points of the 4 first signals are different from each other.

S560, combining the 4 paths of first signals obtained by the frequency mixing technology in the S550;

it should be understood that all signals processed so far are digital signals,

and S570, performing digital-to-analog conversion (DAC) on the signal obtained after the processing in S560, so as to obtain a first combined signal, which is understood to be an analog electrical signal.

It should be understood that the order of S560 and S570 may be interchanged. Optionally, the 1-path first signal and the 2-path first signal may be combined respectively, the 3-path first signal and the 4-path first signal may be combined, then the signals obtained by the two-path combining may be respectively subjected to DAC, and then the two-path analog signal may be combined, which is not limited in the embodiment of the present invention.

It should be understood that the first combined signal obtained at S570 corresponds to, for example, the first combined signal obtained at S250 above.

S580, the analog optical driver module may convert the first combined signal (analog electrical signal) processed in S570 into an optical signal, and then transmit the optical signal to the BBU. The first combined signal (analog electrical signal) obtained by the processing in S570 may also be converted into an electrical differential signal, and then the electrical differential signal is transmitted to the BBU.

It should be noted that the signal transmission method described above with reference to fig. 6 is only an exemplary illustration, and the present invention is not limited thereto. Specifically, for example, the number of paths of signals targeted by steps S510 to S590 is limited to the example shown in fig. 6, for example, only 3 paths of CPRI signals from the RRU are shown in fig. 6, and there may be more paths in practice; it should be further understood that, for simplicity and convenience of description, only the intermediate frequency signals with the same number of paths as the CPRI signals are shown in fig. 6, but not limited thereto, in fact, one path of CPRI signals may include multiple paths of intermediate frequency signals, for example, one path of CPRI signals may include 4 paths of intermediate frequency signals, and based on this, in the embodiment of the present invention, the CPRI deframing performed in S510 may obtain 12 paths of intermediate frequency signals in total. It should also be understood that for simplicity and ease of description, only one signal is shown in fig. 6 to represent an ethernet signal, and in practice, there may be multiple ethernet signals.

Therefore, the signal transmission method provided by the embodiment of the invention can be applied to any multi-channel digital signal transmission scene, can reduce the transmission cost, and can improve the signal transmission efficiency.

Fig. 7 shows a schematic flowchart of a signal transmission method 600 provided according to an embodiment of the present invention, where an execution subject of the method 600 is, for example, the second signal transmission apparatus 100B shown in fig. 1, and for convenience of description and understanding, it is assumed that a signal transmission scenario shown in fig. 7 is the same as a scenario shown in fig. 6: the 3 CPRI signals from the RRUs are transmitted to the BBU, and the ethernet signals (signals including ethernet data) of other network elements (e.g., an LTE base station, a UMTS base station, or a GSM base station) are transmitted to a next node, e.g., a core network. The second signal transmission device 100B is directly connected to the first signal transmission device 100A through an optical fiber or a cable, and may transmit an optical signal or an electrical differential signal. As shown in fig. 7, the method 600 includes:

s610, receiving an optical signal or an electrical differential signal from the RRU side, assuming that the optical signal or the electrical differential signal is a signal obtained by converting the first combined signal in S580 by the method 500. The first combined signal is obtained by converting the optical signal or the electrical differential signal into an analog electrical signal.

S620, performing analog-to-digital conversion (ADC) on the first combined signal obtained in S610 to obtain a corresponding digital signal;

s630, carrying out shunt processing on the digital signal obtained in the S620 to obtain 4 paths of first signals;

it should be understood that the 4 first signals obtained here correspond to the 4 first signals obtained at S560 above (not necessarily all identical).

And S640, performing frequency mixing processing on the 4 paths of first signals obtained in the S630, specifically, modulating 3 paths of first signals to an intermediate frequency respectively from the current frequency point to obtain 3 paths of intermediate frequency signals, modulating the remaining 1 path of first signals to the intermediate frequency from the current frequency point, and performing demodulation processing to obtain an Ethernet signal.

It will be appreciated that the above conversion from 4 first signals to 3 intermediate frequency signals and 1 ethernet signal may be achieved by mixers according to the current art. It should be noted that, in this process, the local oscillation configuration of the mixer corresponds to the local oscillation configuration of the mixer in S550 one-to-one. For example, by configuring the local oscillator of the mixer to the frequency point f1, the 1 st path of first signal (which may be any path of the 4 paths of first signals) in the 4 paths of first signals may be modulated into the 1 st path of intermediate frequency signal; the 2 nd path of first signals in the 4 paths of first signals can be modulated into the 2 nd path of intermediate frequency signals by configuring the local oscillator of the frequency mixer to a frequency point f 2; the 3 rd path first signal in the 4 paths of first signals can be modulated into the 3 rd path intermediate frequency signal by configuring the local oscillator of the frequency mixer to a frequency point f 3; by configuring the local oscillator of the mixer to the frequency point f4, it may be achieved that the 4 th path first signal in the 4 paths of first signals is modulated into an ethernet signal, as shown in fig. 7.

It should be noted that, assuming that the execution main body of the method 500 is the first signal transmission apparatus 100A in fig. 1, the execution main body of the method 600 is the second signal transmission apparatus 100B in fig. 1, the first signal transmission apparatus 100A and the second signal transmission apparatus 100B may share one management layer device, assuming that the first signal transmission apparatus 100A allocates different frequency points for the multiple intermediate frequency signals from the RRU side, in the process, a one-to-one correspondence relationship between the number of signal paths and the respective frequency points may be generated, the second signal transmission apparatus 100B may obtain the correspondence relationship through the management layer device, and then, in the process of converting the first signal into the intermediate frequency signal (as shown in S640 in fig. 7), the conversion is performed based on the correspondence relationship.

And S650, aiming at each path of signal in the 3 paths of intermediate frequency signals and the 1 path of Ethernet signals determined in the S640, reducing the signal rate by utilizing a decimation technology, and filtering the interference generated by the decimation technology by a filtering technology.

S660, performing CPRI framing on each path of intermediate frequency signal in the 3 paths of intermediate frequency signals obtained by the S650 processing, namely encapsulating each path of intermediate frequency according to a CPRI protocol to finally obtain 3 paths of CPRI signals, and transmitting the 3 paths of CPRI signals to BBU processing;

it should be understood that the 3 CPRI signals transmitted to the BBU here are the 3 CPPI signals sent by the RRU in fig. 5.

S670 demodulates the 1-channel ethernet signal obtained in S650, and it is assumed that in S590 of method 500 shown in fig. 6, the ethernet signal is QAM modulated, and correspondingly, QAM scheme demodulation is adopted here. Furthermore, if in S590 of the method 500 shown in fig. 6, channel coding, such as FEC coding, is also performed before the ethernet signal is subjected to the shaping filtering and modulation, then in this step, it is also necessary to perform a corresponding decoding operation after the demodulation in S670.

As can be seen from the above method 500 shown in fig. 6 and the method 600 shown in fig. 7, in the embodiment of the present invention, for multiple channels of protocol-encapsulated signals (digital signals) transmitted between the sending device and the receiving device, on the sending device side, protocol deframing processing is performed on each channel of protocol-encapsulated signals to obtain signals (denoted as useful signals) only containing pure useful data, and then the multiple channels of useful signals are combined and subjected to digital-to-analog conversion processing to obtain combined signals in the analog domain, and the combined signals are converted into optical signals or electrical differential signals to be transmitted to the receiving device. And at the side of the receiving equipment, the combined signal from the side of the sending equipment is subjected to shunting processing, analog-to-digital conversion processing and protocol framing processing, the originally sent multi-channel protocol encapsulated signal of the sending equipment is finally recovered, and finally the multi-channel protocol encapsulated signal is transmitted to the receiving equipment. The protocol encapsulated signal is converted into a radio frequency signal, and the radio frequency signal is transmitted by using an optical fiber or a cable, and the protocol encapsulated signal is recovered from the radio frequency signal at the receiving equipment side.

In summary, compared with the prior art, the signal transmission method provided by the embodiment of the invention can effectively reduce the consumption of the transmission cable and can improve the signal transmission efficiency.

Therefore, in the embodiment of the present invention, for a plurality of CPRI signals that need to be transmitted from a first device to a second device, first, an intermediate frequency signal is extracted from the CPRI signal, then, different frequency points are allocated to the plurality of intermediate frequency signals, and the plurality of intermediate frequency signals are modulated to the frequency points allocated to the plurality of intermediate frequency signals, so as to obtain corresponding first signals, then, a combining process and a digital-to-analog conversion process are performed on the plurality of first signals, so as to obtain a combined signal, and the combined signal is transmitted to the second device; and at the second equipment side, carrying out shunting and analog-to-digital conversion processing on the combined signal to obtain a plurality of paths of first signals, then demodulating the first signals to obtain corresponding intermediate frequency signals, carrying out CPRI framing on the intermediate frequency signals to obtain corresponding CPRI signals, and finally transmitting the plurality of paths of CPRI signals to the second equipment for processing. The transmission of multi-path CPRI signals between the first equipment and the second equipment is realized by using less transmission cables, so that the consumption of the transmission cables can be effectively reduced; in addition, because the intermediate frequency signal is extracted from the CPRI signal for processing and transmission, compared with the prior art in which the CPRI signal is transmitted through, the signal transmission efficiency can be effectively improved.

The signal transmission method according to the embodiment of the present invention is described in detail above with reference to fig. 1 to 7, and the signal transmission device according to the embodiment of the present invention is described in detail below with reference to fig. 8 to 10.

Fig. 8 shows a schematic block diagram of a signal transmission arrangement 700 according to an embodiment of the invention, the arrangement 700 comprising:

a first receiving module 710, configured to receive N paths of common radio interface CPRI signals sent by a first device, where the CPRI signals are signals obtained by encapsulating intermediate frequency signals according to a CPRI protocol, and N is an integer greater than or equal to 1;

a first determining module 720, configured to determine M paths of intermediate frequency signals according to the N paths of CPRI signals received by the first receiving module, where the M paths of intermediate frequency signals include all intermediate frequency signals extracted from the N paths of CPRI signals, and M is an integer greater than or equal to N;

specifically, the first determining module 720 may also be referred to as a CPRI deframing module.

A modulation module 730, configured to allocate a frequency point to each of the M channels of intermediate frequency signals determined by the first determination module, and modulate each channel of intermediate frequency signal to the frequency point allocated to each channel of intermediate frequency signal to obtain a first signal, where the frequency points allocated to different channels of intermediate frequency signals are different;

specifically, the modulation module 730 includes, for example, a mixer, and different frequency points are configured by, for example, local oscillators of the mixer, so that the intermediate frequency signals in different paths can be moved to the frequency points allocated to the respective frequency points.

A combining and digital-to-analog converting module 740, configured to perform combining processing and digital-to-analog converting processing on the M channels of first signals obtained by the modulating module, to determine a first combined signal, where the first combined signal is an analog electrical signal;

a first transmitting module 750, configured to transmit the first combined signal obtained by the combining and digital-to-analog converting module to a second device.

Referring to fig. 1, when the first device is an RRU and the second device is a BBU, the signal transmission apparatus 700 is specifically the first signal transmission apparatus 100A shown in fig. 1. When the first device is a BBU and the second device is an RRU, the signal transmission apparatus 700 is specifically the second signal transmission apparatus 100B shown in fig. 1.

Optionally, in an embodiment of the present invention, as shown in fig. 9, the apparatus 700 further includes:

a second determining module 760, configured to determine a power constraint value and a gain adjustment coefficient of each channel of intermediate frequency signals according to a signal power threshold of an analog channel and the number M of the M channels of intermediate frequency signals before the modulating module allocates a frequency point to each channel of intermediate frequency signals in the M channels of intermediate frequency signals 730, where the analog channel represents a channel for transmitting the first combined signal;

a power adjusting module 770, configured to perform power range adjustment on the if signal according to the gain adjustment coefficient determined by the second determining module, so that the power value of the if signal after the power range adjustment does not exceed the power constraint value.

It should be appreciated that the second determining module 760 and the power adjusting module 770 are each configured to process each if signal separately.

Optionally, in an embodiment of the present invention, the modulation module 730 includes:

a sampling unit 731, configured to perform signal sampling on each channel of intermediate frequency signal at a first rate, and perform image rejection filtering processing on each channel of intermediate frequency signal obtained by sampling, where the first rate is the rate of the maximum intermediate frequency signal in the M channels of intermediate frequency signals;

a signal rate increasing unit 732, configured to increase, by using an interpolation technique, a signal rate of the intermediate frequency signal of each channel processed by the sampling unit, and perform interference filtering processing on the intermediate frequency signal of each channel after the rate increase;

and the modulating unit 733 element allocates a frequency point for each path of intermediate frequency signal processed by the signal rate increasing unit, and modulates each path of intermediate frequency signal to the frequency point allocated for each path of intermediate frequency signal to obtain the first signal.

Optionally, in this embodiment of the present invention, the combining and digital-to-analog converting module 740 includes at least one combining unit 741 and at least one digital-to-analog converting unit 742.

Specifically, the combining unit 741 may combine the M first signals, which is equivalent to combining in a digital domain, and the digital-to-analog conversion unit 742 performs digital-to-analog conversion (D/a conversion) on the combined signal in the digital domain processed by the combining unit 741, so as to obtain the first combined signal (analog signal); alternatively, the digital-to-analog converting unit 742 performs D/a conversion on the M first signals respectively to obtain M analog signals, and then the combining unit 741 performs combining processing on the M analog signals obtained by the digital-to-analog converting unit 742, which is equivalent to combining in an analog domain, so as to obtain the first combined signal finally.

Optionally, in the embodiment of the present invention, the combining and digital-to-analog converting module 740 includes G1 combining units 741 and G1-1 digital-to-analog converting units 742, where G1 and G2 are both integers greater than 1. The first to G1-1 combining units 741 in the G1 combining units 741 respectively perform digital domain combining processing on partial signals in the M first signals to correspondingly obtain G1-1 sub-combined signals, and it should be understood that first signals processed by different combining units 741 in the 1 st to G1-1 combining units 741 are different from each other, in other words, the M first signals are divided into G1-1 groups, and the groups are subjected to combining processing. G1-1 digital-to-analog conversion units 742 respectively perform D/A conversion on the G1-1 path sub-combined path signals to obtain G1-1 path analog signals; then, the G1 combination unit 741 of the G1 combination units 741 combines the G1-1 analog signals to obtain the first combined signal.

Optionally, in an embodiment of the present invention, the first transmission module 750 includes:

a conversion unit 751, configured to convert the first combined signal into an optical signal or an electrical differential signal;

a transmission unit 752 for transmitting the optical signal or the electrical differential signal obtained by the conversion unit to the second device.

Specifically, the first transmission module is, for example, an analog type optical driving module.

Optionally, in this embodiment of the present invention, M is an integer greater than N, and the first receiving module 710 is further configured to receive an ethernet signal sent by a third device;

It should be understood that the above and other operations and/or functions of the respective modules 710 to 770 in the signal transmission device 700 are respectively for implementing the corresponding flows of the respective methods in fig. 6.

Optionally, in an embodiment of the present invention, as shown in fig. 10, the apparatus 700 further includes:

a second receiving module 810, configured to receive a second combined signal from the second device, where the second combined signal is a combined signal obtained by performing combining processing and digital-to-analog conversion processing on Q channels of second signals, where frequency points of second signals in different channels of the Q channels of second signals are different from each other, and an ith channel of second signal is a signal obtained by modulating an ith channel of intermediate frequency signal according to an ith frequency point, i is 1,2,.

A splitting and analog-to-digital converting module 820, configured to perform splitting processing and analog-to-digital converting processing on the second combined signal received by the second receiving module, so as to obtain Q paths of second signals;

a demodulation module 830, configured to demodulate, according to the ith frequency point, the ith second signal in the Q second signals obtained by the branch circuit and analog-to-digital conversion module into the ith intermediate frequency signal;

a third determining module 840, configured to perform CPRI protocol encapsulation on the Q-path intermediate frequency signal obtained by the demodulating module, and determine the P-path CPRI signal;

a second transmission module 850, configured to transmit the P-way CPRI signal determined by the third determination module to the first device.

Optionally, in an embodiment of the present invention, the apparatus 700 further includes:

a signal rate reduction module 860, configured to perform a signal rate reduction process and an interference filtering process on the intermediate frequency signal of each path before the third determining module 840 determines the P paths of CPRI signals.

It should be understood that the above and other operations and/or functions of the respective modules 810 to 860 in the above signal transmission apparatus 700 are respectively for implementing the corresponding flows of the respective methods in fig. 7.

Optionally, in this embodiment of the present invention, the first device is a radio remote unit, and the second device is a baseband unit; or

It should be understood that the signal transmission apparatus 700 according to the embodiment of the present invention may correspond to the first signal transmission apparatus 100A or the second signal transmission apparatus 100B in the method according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the signal transmission apparatus 700 are respectively for implementing corresponding flows of each method in fig. 2 to fig. 7, and are not repeated herein for brevity.

As shown in fig. 11, the embodiment of the present invention further provides a signal transmission apparatus 900, and the signal transmission apparatus 900 includes a processor 910, a memory 920, a bus system 930, a receiver 940 and a transmitter 950. Wherein, the processor 910, the memory 920, the receiver 940 and the transmitter 950 are connected via the bus system 930, the memory 920 is used for storing instructions, and the processor 910 is used for executing the instructions stored in the memory 920 to control the receiver 940 to receive signals and control the transmitter 950 to transmit signals. The receiver 940 is configured to receive N paths of common radio interface CPRI signals from the first device, where the CPRI signals are signals obtained by encapsulating intermediate frequency signals according to a CPRI protocol, and N is an integer greater than or equal to 1; the processor 910 is configured to determine M paths of intermediate frequency signals according to the N paths of CPRI signals, where the M paths of intermediate frequency signals include all intermediate frequency signals extracted from the N paths of CPRI signals, and M is an integer greater than or equal to N; distributing frequency points for each path of intermediate frequency signals in the M paths of intermediate frequency signals, and modulating each path of intermediate frequency signals to the frequency points distributed for each path of intermediate frequency signals to obtain first signals, wherein the frequency points distributed for the intermediate frequency signals of different paths are different; determining a first combined signal by performing combining processing and digital-to-analog conversion processing on the M paths of first signals, wherein the first combined signal is an analog electric signal; the transmitter 950 is configured to transmit the first combined signal to a second device.

Optionally, in this embodiment of the present invention, the processor 910 is specifically configured to, before allocating a frequency point to each of the M intermediate frequency signals, determine a power constraint value and a gain adjustment coefficient of each intermediate frequency signal according to a signal power threshold of an analog channel and the number M of the M intermediate frequency signals, where the analog channel represents a channel for transmitting the first combined signal; and adjusting the power range of each path of intermediate frequency signal according to the gain adjustment coefficient, so that the power value of each path of intermediate frequency signal after the power range adjustment does not exceed the power constraint value.

Optionally, in this embodiment of the present invention, the processor 910 is specifically configured to perform signal sampling on each path of intermediate frequency signals by using a first rate, and perform image rejection filtering processing on each path of intermediate frequency signals obtained by the sampling, where the first rate is a rate of an intermediate frequency signal with a maximum rate in the M paths of intermediate frequency signals;

Optionally, in this embodiment of the present invention, the processor 910 is specifically configured to convert the first combined signal into an optical signal or an electrical differential signal;

the transmitter 950 is specifically configured to transmit the optical signal or the electrical differential signal to the second device.

Optionally, in this embodiment of the present invention, M is an integer greater than N, and the receiver 940 is further configured to receive an ethernet signal from a third device;

Optionally, in this embodiment of the present invention, the receiver 940 is further configured to receive a second combined signal from the second device, where the second combined signal is a combined signal obtained by performing combining processing and digital-to-analog conversion processing on Q channels of second signals, where frequency points of second signals in different channels of the Q channels of second signals are different from each other, and an ith channel of second signal is a signal obtained by modulating an ith channel of intermediate frequency signal according to an ith frequency point, i is 1,2,.

The processor 910 is further configured to perform a splitting process and an analog-to-digital conversion process on the second combined signal to obtain Q second signals; demodulating the ith path of second signal into the ith path of intermediate frequency signal according to the ith frequency point; determining the P paths of CPRI signals by performing CPRI protocol encapsulation on the obtained Q paths of intermediate frequency signals;

the transmitter 950 is further configured to transmit the P-channel CPRI signal to the first device.

Optionally, in this embodiment of the present invention, the processor 910 is specifically configured to perform signal rate reduction processing and interference filtering processing on each path of intermediate frequency signal before performing CPRI protocol encapsulation on the obtained Q path of intermediate frequency signal and determining the P path of CPRI signal.

Optionally, in this embodiment of the present invention, the processor 910 is specifically configured to enable the first device to be a radio remote unit, and enable the second device to be a baseband unit; or

It should be understood that, in the embodiment of the present invention, the processor 910 may be a Central Processing Unit (CPU), and the processor 910 may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 920 may include a read-only memory and a random access memory, and provides instructions and data to the processor 910. A portion of the memory 920 may also include non-volatile random access memory. For example, the memory 920 may also store device type information.

The bus system 930 may include a power bus, a control bus, a status signal bus, and the like, in addition to a data bus. For clarity of illustration, however, the various buses are designated in the figure as the bus system 930.

In implementation, the steps of the above method may be performed by integrated logic circuits of hardware or instructions in the form of software in the processor 910. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in the memory 920, and the processor 910 reads the information in the memory 920 and performs the steps of the above method in combination with the hardware thereof. To avoid repetition, it is not described in detail here.

Therefore, in the embodiment of the present invention, for a plurality of CPRI signals that need to be transmitted from a first device to a second device, first, an intermediate frequency signal is extracted from the CPRI signal, then, different frequency points are allocated to the plurality of intermediate frequency signals, and the plurality of intermediate frequency signals are modulated to the frequency points allocated to the plurality of intermediate frequency signals, so as to obtain corresponding first signals, then, a combining process and a digital-to-analog conversion process are performed on the plurality of first signals, so as to obtain a combined signal, and the combined signal is transmitted to the second device; and at the second equipment side, carrying out shunting and analog-to-digital conversion processing on the combined signal to obtain a plurality of paths of first signals, then demodulating the first signals to obtain corresponding intermediate frequency signals, carrying out CPRI framing on the intermediate frequency signals to obtain corresponding CPRI signals, and finally transmitting the plurality of paths of CPRI signals to the second equipment for processing. The transmission of multi-path CPRI signals between the first equipment and the second equipment is realized by using less transmission cables, so that the consumption of the transmission cables can be effectively reduced; in addition, because the intermediate frequency signal is extracted from the CPRI signal for processing and transmission, compared with the prior art in which the CPRI signal is transmitted through, the efficiency of signal transmission can be effectively improved

It should be understood that the signal transmission apparatus 900 according to the embodiment of the present invention may correspond to the first signal transmission apparatus 100A or the second signal transmission apparatus 100B in the signal transmission method according to the embodiment of the present invention, and may correspond to the signal transmission apparatus 700 according to the embodiment of the present invention, and the above and other operations and/or functions of each module in the apparatus 900 are respectively for implementing corresponding flows of each method in fig. 1 to fig. 7, and are not described herein again for brevity.

It should also be understood that the reference herein to first, second, and various numerical designations is merely for convenience of description and is not intended to limit the scope of embodiments of the invention.

It should be understood that the term "and/or" herein is merely one type of association relationship that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

It should be understood that, in various embodiments of the present invention, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A signal transmission method, comprising:

and transmitting the first combined signal to a second device.

2. The method according to claim 1, wherein before allocating a frequency point for each of the M if signals, the method further comprises:

3. The method according to claim 1 or 2, wherein the allocating a frequency point for each of the M channels of intermediate frequency signals comprises:

the signal rate of each path of intermediate frequency signals after the image rejection filtering processing is improved through an interpolation technology, and interference filtering processing is carried out on each path of intermediate frequency signals after the rate is improved;

and distributing frequency points for the intermediate frequency signals subjected to the interference filtering processing, and modulating the intermediate frequency signals to the frequency points distributed for the intermediate frequency signals to obtain the first signals.

4. The method of claim 1 or 2, wherein said transmitting the first combined signal to a second device comprises:

transmitting the optical signal or electrical differential signal to the second device.

5. The method of claim 1 or 2, wherein M is an integer greater than N, the method further comprising:

receiving an Ethernet signal sent by third equipment;

6. The method according to claim 1 or 2, characterized in that the method further comprises:

Obtaining the Q-path second signal by performing shunting processing and analog-to-digital conversion processing on the second combined signal;

performing CPRI protocol encapsulation on the obtained Q paths of intermediate frequency signals to determine the P paths of CPRI signals;

and transmitting the P path of CPRI signal to the first equipment.

7. The method of claim 6, wherein before determining the P-way CPRI signal by performing CPRI protocol encapsulation on the obtained Q-way IF signal, the method further comprises:

8. The method of claim 1 or 2, wherein the first device is a radio remote unit and the second device is a baseband unit; or

9. A signal transmission apparatus, comprising:

the first receiving module is used for receiving N paths of common radio interface (CPRI) signals for common use sent by first equipment, the CPRI signals are obtained by packaging intermediate frequency signals according to a CPRI protocol, and N is an integer greater than or equal to 1;

the combining and digital-to-analog conversion module is used for determining a first combined signal by performing combining processing and digital-to-analog conversion processing on the M paths of first signals obtained by the modulation module, wherein the first combined signal is an analog electric signal;

and the first transmission module is used for transmitting the first combined signal obtained by the combined path and digital-to-analog conversion module to second equipment.

10. The apparatus of claim 9, further comprising:

a second determining module, configured to determine a power constraint value and a gain adjustment coefficient of each channel of intermediate frequency signals according to a signal power threshold of an analog channel and a channel number M of the M channels of intermediate frequency signals before the modulating module allocates a frequency point to each channel of intermediate frequency signals in the M channels of intermediate frequency signals, where the analog channel represents a channel for transmitting the first combined signal;

and the power adjusting module is configured to perform power range adjustment on each path of intermediate frequency signal according to the gain adjustment coefficient determined by the second determining module, so that the power value of each path of intermediate frequency signal after the power range adjustment does not exceed the power constraint value.

11. The apparatus of claim 9 or 10, wherein the modulation module comprises:

the sampling unit is used for performing signal sampling on each path of intermediate frequency signal by using a first rate, and performing image rejection filtering processing on each path of intermediate frequency signal obtained by sampling, wherein the first rate is the rate of the intermediate frequency signal with the maximum rate in the M paths of intermediate frequency signals;

12. The apparatus of claim 9 or 10, wherein the first transmission module comprises:

13. The apparatus according to claim 9 or 10, wherein M is an integer greater than N, and the first receiving module is further configured to receive an ethernet signal sent by a third device;

14. The apparatus of claim 9 or 10, further comprising:

a second receiving module, configured to receive a second combined signal from the second device, where the second combined signal is a combined signal obtained by performing combining processing and digital-to-analog conversion processing on Q channels of second signals, frequency points of second signals in different channels of the Q channels of second signals are different from each other, and an ith channel of second signal is a signal obtained by modulating an ith channel of intermediate frequency signal according to an ith frequency point, i is 1,2,.

a third determining module, configured to perform CPRI protocol encapsulation on the Q-path intermediate frequency signal obtained by the demodulating module, to determine the P-path CPRI signal;

15. The apparatus of claim 14, further comprising:

16. The apparatus according to claim 9 or 10, wherein the first device is a radio remote unit, and the second device is a baseband unit; or