阅读说明：本技术 一种分段连续调频波的信号调制解调方法及系统 (Signal modulation and demodulation method and system for segmented continuous frequency modulation wave ) 是由 王继良 李映辉 谢鹏瑾 刘云浩 于 2020-12-16 设计创作，主要内容包括：本发明提供一种分段连续调频波的信号调制解调方法及系统,包括：发送端通过调整待调制数据信号的起始频率,获得调制后分段连续调频波；接收端通过对接收到的所述调制后分段连续调频波进行解扩频和傅里叶变换,得到解扩频信号起始频率,并由所述解扩频信号起始频率得到解调后信号。本发明通过分段连续调频波调制信号构建多个相互正交的分段连续调频波,不同的节点可以使用不同的分段连续调频波传输数据,接收端可以同时解码来自不同节点的信号,该方法可以支持高并发的场景；同时,该方法还保留了长距离、低功耗的特性,可以支持极低信噪比下的信号传输。(The invention provides a signal modulation and demodulation method and a system of a segmented continuous frequency modulation wave, comprising the following steps: the method comprises the steps that a sending end obtains a modulated segmented continuous frequency modulation wave by adjusting the initial frequency of a data signal to be modulated; and the receiving terminal performs despreading and Fourier transform on the received modulated segmented continuous frequency modulation wave to obtain the initial frequency of a despread signal, and obtains a demodulated signal according to the initial frequency of the despread signal. According to the invention, a plurality of mutually orthogonal segmented continuous frequency modulation waves are constructed by the segmented continuous frequency modulation wave modulation signals, different nodes can use different segmented continuous frequency modulation waves to transmit data, and a receiving end can simultaneously decode signals from different nodes, so that the method can support a high-concurrency scene; meanwhile, the method also keeps the characteristics of long distance and low power consumption, and can support signal transmission under an extremely low signal-to-noise ratio.)

1. A method for modulating and demodulating a signal of a segmented continuous frequency modulated wave, comprising:

the method comprises the steps that a sending end obtains a modulated segmented continuous frequency modulation wave by adjusting the initial frequency of a data signal to be modulated;

and the receiving terminal performs despreading and Fourier transform on the received modulated segmented continuous frequency modulation wave to obtain the initial frequency of a despread signal, and obtains a demodulated signal according to the initial frequency of the despread signal.

2. The method as claimed in claim 1, wherein the transmitting end obtains the modulated segmented continuous frequency modulated wave by adjusting a start frequency of a data signal to be modulated, and the method further comprises:

and acquiring a preset segmented continuous frequency modulation wave.

3. The method according to claim 2, wherein the obtaining of the preset piecewise continuous frequency modulation wave specifically comprises:

acquiring subcarriers with preset number, equal preset duration and non-overlapping frequency domains, wherein each subcarrier is a continuous frequency modulation wave;

setting a subcarrier period, a subcarrier bandwidth and a subcarrier starting frequency of each subcarrier, dividing the subcarrier period by the subcarrier bandwidth to obtain a frequency time-varying rate, and obtaining a signal representation of each subcarrier based on the subcarrier bandwidth, the subcarrier period, the frequency time-varying rate and the subcarrier starting frequency;

and obtaining digital permutation based on the preset number, obtaining the initial frequency of any subcarrier based on the digital permutation, and substituting all the initial frequencies of the subcarriers into the signal representation of each subcarrier to obtain the preset segmented continuous frequency modulation wave corresponding to the digital permutation.

4. The method according to claim 3, wherein the sending end obtains the modulated segmented continuous frequency modulated wave by adjusting an initial frequency of a data signal to be modulated, and specifically comprises:

setting the preset bit data for continuously modulating the preset continuous frequency modulation wave, and obtaining the initial frequency of the modulated continuous frequency modulation wave based on the subcarrier bandwidth, the data signal to be modulated and the preset bit data;

and substituting the initial frequency of the modulated segmented continuous frequency modulation wave into the preset segmented continuous frequency modulation wave to obtain the modulated segmented continuous frequency modulation wave.

5. The method as claimed in claim 4, wherein the receiving end obtains a despread signal start frequency by despreading and fourier transforming the received modulated segmented continuous frequency modulated wave, and obtains a demodulated signal from the despread signal start frequency, specifically comprising:

multiplying the modulated segmented continuous frequency modulation wave by the conjugate of the unmodulated segmented continuous frequency modulation wave to obtain a single-frequency signal;

carrying out Fourier transform on the single-frequency signals to obtain intensity distribution signals of the single-frequency signals on each frequency;

calculating to obtain the initial frequency of the de-spread signal based on the intensity distribution signal;

and obtaining the demodulated signal according to the initial frequency of the de-spread signal, the subcarrier bandwidth and the bit data of the preset digit.

6. A segmented continuous frequency modulated wave signal modem system comprising:

the modulation module is used for adjusting the initial frequency of the data signal to be modulated by the sending end to obtain a modulated segmented continuous frequency modulation wave;

and the demodulation module is used for the receiving end to obtain the initial frequency of the de-spread spectrum signal by performing de-spread spectrum and Fourier transform on the received modulated segmented continuous frequency modulation wave and obtain a demodulated signal according to the initial frequency of the de-spread spectrum signal.

7. The system of claim 6, further comprising:

and the acquisition module is used for acquiring the preset segmented continuous frequency modulation wave.

8. The system according to claim 7, wherein the obtaining module is specifically configured to:

acquiring subcarriers with preset number, equal preset duration and non-overlapping frequency domains, wherein each subcarrier is a continuous frequency modulation wave;

setting a subcarrier period, a subcarrier bandwidth and a subcarrier starting frequency of each subcarrier, dividing the subcarrier period by the subcarrier bandwidth to obtain a frequency time-varying rate, and obtaining a signal representation of each subcarrier based on the subcarrier bandwidth, the subcarrier period, the frequency time-varying rate and the subcarrier starting frequency;

and obtaining digital permutation based on the preset number, obtaining the initial frequency of any subcarrier based on the digital permutation, and substituting all the initial frequencies of the subcarriers into the signal representation of each subcarrier to obtain the preset segmented continuous frequency modulation wave corresponding to the digital permutation.

9. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor when executing the computer program implements the steps of the method for signal modulation and demodulation of a segmented continuous frequency modulated wave according to any one of claims 1 to 5.

10. A non-transitory computer-readable storage medium, on which a computer program is stored, wherein the computer program, when being executed by a processor, implements the steps of the method for signal modulation and demodulation of a segmented continuous frequency modulated wave according to any one of claims 1 to 5.

Technical Field

The invention relates to the technical field of information communication, in particular to a signal modulation and demodulation method and system of a segmented continuous frequency modulation wave.

Background

The low-power-consumption wide area network technology is a novel network technology, can provide an ultra-low-power-consumption long-distance network communication mode, and has wide application prospects in typical Internet of things applications such as intelligent agriculture, intelligent cities and industrial Internet.

In the low-power-consumption wide area network, the nodes are accessed to the network through the gateway, and the signal modulation and demodulation mode between the nodes and the gateway determines the basic performance of the network. Existing low-power-consumption wide area network computing, such as LoRa, uses a frequency modulated continuous wave (CSS) method for signal modulation, and by concentrating energy over the entire frequency spectrum to a single frequency, signal transmission at an extremely low signal-to-noise ratio can be achieved, thereby achieving low-power consumption and long-distance network communication. However, in a scenario of multi-node concurrent transmission, frequency modulated continuous waves sent by different nodes interfere with each other, which results in decoding failure, and therefore, multiple nodes cannot send data packets in parallel, and can only avoid signal interference through scheduling in a time dimension. No better solution has been proposed for modulation of frequency modulated signals at the transmitting end and demodulation at the receiving end.

Disclosure of Invention

The invention provides a signal modulation and demodulation method and a signal modulation and demodulation system for a segmented continuous frequency modulation wave, which are used for solving the defect that the prior art can not support multi-node parallel data packet transmission.

In a first aspect, the present invention provides a signal modulation and demodulation method for a segmented continuous frequency modulated wave, including:

the method comprises the steps that a sending end obtains a modulated segmented continuous frequency modulation wave by adjusting the initial frequency of a data signal to be modulated;

and the receiving terminal performs despreading and Fourier transform on the received modulated segmented continuous frequency modulation wave to obtain the initial frequency of a despread signal, and obtains a demodulated signal according to the initial frequency of the despread signal.

Further, the sending end obtains the modulated segmented continuous frequency modulation wave by adjusting the initial frequency of the data signal to be modulated, and the method also includes the following steps:

and acquiring a preset segmented continuous frequency modulation wave.

Further, the acquiring of the preset segmented continuous frequency modulation wave specifically includes:

acquiring subcarriers with preset number, equal preset duration and non-overlapping frequency domains, wherein each subcarrier is a continuous frequency modulation wave;

setting a subcarrier period, a subcarrier bandwidth and a subcarrier starting frequency of each subcarrier, dividing the subcarrier period by the subcarrier bandwidth to obtain a frequency time-varying rate, and obtaining a signal representation of each subcarrier based on the subcarrier bandwidth, the subcarrier period, the frequency time-varying rate and the subcarrier starting frequency;

and obtaining digital permutation based on the preset number, obtaining the initial frequency of any subcarrier based on the digital permutation, and substituting all the initial frequencies of the subcarriers into the signal representation of each subcarrier to obtain the preset segmented continuous frequency modulation wave corresponding to the digital permutation.

Further, the sending end obtains the modulated segmented continuous frequency modulation wave by adjusting the initial frequency of the data signal to be modulated, and specifically includes:

setting the preset bit data for continuously modulating the preset continuous frequency modulation wave, and obtaining the initial frequency of the modulated continuous frequency modulation wave based on the subcarrier bandwidth, the data signal to be modulated and the preset bit data;

and substituting the initial frequency of the modulated segmented continuous frequency modulation wave into the preset segmented continuous frequency modulation wave to obtain the modulated segmented continuous frequency modulation wave.

Further, the receiving end performs despreading and fourier transform on the received modulated segmented continuous frequency modulation wave to obtain a despread signal start frequency, and obtains a demodulated signal from the despread signal start frequency, which specifically includes:

multiplying the modulated segmented continuous frequency modulation wave by the conjugate of the unmodulated segmented continuous frequency modulation wave to obtain a single-frequency signal;

carrying out Fourier transform on the single-frequency signals to obtain intensity distribution signals of the single-frequency signals on each frequency;

calculating to obtain the initial frequency of the de-spread signal based on the intensity distribution signal;

and obtaining the demodulated signal according to the initial frequency of the de-spread signal, the subcarrier bandwidth and the bit data of the preset digit.

In a second aspect, the present invention further provides a segmented continuous frequency modulated wave signal modulation and demodulation system, comprising:

the modulation module is used for adjusting the initial frequency of the data signal to be modulated by the sending end to obtain a modulated segmented continuous frequency modulation wave;

and the demodulation module is used for the receiving end to obtain the initial frequency of the de-spread spectrum signal by performing de-spread spectrum and Fourier transform on the received modulated segmented continuous frequency modulation wave and obtain a demodulated signal according to the initial frequency of the de-spread spectrum signal.

Further, still include:

and the acquisition module is used for acquiring the preset segmented continuous frequency modulation wave.

Further, the obtaining module is specifically configured to:

acquiring subcarriers with preset number, equal preset duration and non-overlapping frequency domains, wherein each subcarrier is a continuous frequency modulation wave;

setting a subcarrier period, a subcarrier bandwidth and a subcarrier starting frequency of each subcarrier, dividing the subcarrier period by the subcarrier bandwidth to obtain a frequency time-varying rate, and obtaining a signal representation of each subcarrier based on the subcarrier bandwidth, the subcarrier period, the frequency time-varying rate and the subcarrier starting frequency;

and obtaining digital permutation based on the preset number, obtaining the initial frequency of any subcarrier based on the digital permutation, and substituting all the initial frequencies of the subcarriers into the signal representation of each subcarrier to obtain the preset segmented continuous frequency modulation wave corresponding to the digital permutation.

In a third aspect, the present invention further provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the signal modulation and demodulation method of the segmented continuous frequency modulated wave as described in any one of the above.

In a fourth aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, implements the steps of the method for signal modulation and demodulation of a segmented continuous frequency modulated wave as described in any one of the above.

According to the signal modulation and demodulation method and system of the segmented continuous frequency modulation wave, a plurality of mutually orthogonal segmented continuous frequency modulation waves are constructed through the segmented continuous frequency modulation wave modulation signals, different nodes can use different segmented continuous frequency modulation waves to transmit data, and a receiving end can simultaneously decode signals from different nodes, so that the method can support a high-concurrency scene; meanwhile, the method also keeps the characteristics of long distance and low power consumption, and can support signal transmission under an extremely low signal-to-noise ratio.

Drawings

In order to more clearly illustrate the technical solutions of the present invention or the prior art, the drawings needed for 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 some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

FIG. 1 is a schematic flow chart of a signal modulation and demodulation method for a segmented continuous FM wave provided by the invention;

FIG. 2 is a schematic diagram of a segmented continuous FM wave provided by the present invention;

FIG. 3 is a schematic diagram of signal demodulation provided by the present invention;

FIG. 4 is a schematic diagram of a signal modem system for segmented continuous FM waves according to the present invention;

fig. 5 is a schematic structural diagram of an electronic device provided in the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are some, but 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.

Aiming at the defect that the low-power-consumption wide area network modulation technology in the prior art cannot support concurrent transmission, a novel segmented continuous frequency modulation wave signal modulation and demodulation method is provided, and low-power-consumption, long-distance and high-concurrency communication can be supported.

Fig. 1 is a schematic flow chart of a signal modulation and demodulation method of a segmented continuous frequency modulated wave provided by the present invention, as shown in fig. 1, including:

s1, the sending end obtains the modulated segmented continuous frequency modulation wave by adjusting the initial frequency of the data signal to be modulated;

s2, the receiving end obtains the initial frequency of the de-spread spectrum signal by de-spreading and Fourier transform of the received modulated segmented continuous frequency modulation wave, and obtains the demodulated signal by the initial frequency of the de-spread spectrum signal.

Specifically, a sending end for sending a signal adjusts the initial frequency of a data signal to obtain a modulated segmented continuous frequency modulation wave, the modulated segmented continuous frequency modulation wave is sent to a receiving end, and the receiving end performs despreading and Fourier transform processing on the modulated segmented continuous frequency modulation wave to obtain the initial frequency of a despread signal and obtain a demodulated signal.

According to the invention, a plurality of mutually orthogonal segmented continuous frequency modulation waves are constructed through the segmented continuous frequency modulation wave modulation signals, different nodes can use different segmented continuous frequency modulation waves to transmit data, and a receiving end can simultaneously decode signals from different nodes.

Based on the above embodiment, the method step S1 is preceded by:

and acquiring a preset segmented continuous frequency modulation wave.

The acquiring of the preset segmented continuous frequency modulation wave specifically comprises:

acquiring subcarriers with preset number, equal preset duration and non-overlapping frequency domains, wherein each subcarrier is a continuous frequency modulation wave;

setting a subcarrier period, a subcarrier bandwidth and a subcarrier starting frequency of each subcarrier, dividing the subcarrier period by the subcarrier bandwidth to obtain a frequency time-varying rate, and obtaining a signal representation of each subcarrier based on the subcarrier bandwidth, the subcarrier period, the frequency time-varying rate and the subcarrier starting frequency;

and obtaining digital permutation based on the preset number, obtaining the initial frequency of any subcarrier based on the digital permutation, and substituting all the initial frequencies of the subcarriers into the signal representation of each subcarrier to obtain the preset segmented continuous frequency modulation wave corresponding to the digital permutation.

Specifically, as shown in fig. 2, a segmented continuous frequency modulated wave is composed of M subcarriers that are equal in duration and non-overlapping in frequency domain, where M is a positive integer, and each subcarrier is a continuous frequency modulated wave. Assuming that the period of the segmented continuous frequency modulation wave is T and the bandwidth is B, each subcarrier can be represented by the following formula:

where f is the starting frequency of the subcarrier, k is the rate at which the frequency changes over time,f + ktmodB indicates that the frequency exceeds the bandwidth B and then is inverted to 0, and a segmented continuous wave can be in one-to-one correspondence with a sequence from 0 to M-1.

Let s be { s [0 ]]，s[1],., s [ M-1 ] is a permutation of numbers 0 to M-1, the starting frequency of which is for the ith sub-carrierThus, the piecewise continuous frequency modulated wave corresponding to the permutation s can be expressed as:

sc_s＝{c_s[0]，c_s[1]，...，c_s[M-1]}

wherein the content of the first and second substances,

the invention provides signal input for data modulation by changing the initial frequency of the signal subsequently by designing the segmented continuous frequency modulation wave.

Based on any of the above embodiments, step S1 in the method specifically includes:

setting the preset bit data for continuously modulating the preset continuous frequency modulation wave, and obtaining the initial frequency of the modulated continuous frequency modulation wave based on the subcarrier bandwidth, the data signal to be modulated and the preset bit data;

and substituting the initial frequency of the modulated segmented continuous frequency modulation wave into the preset segmented continuous frequency modulation wave to obtain the modulated segmented continuous frequency modulation wave.

Specifically, by changing the initial frequency modulation signal of the segmented continuous frequency modulation wave, assuming that one segmented continuous frequency modulation wave modulates p-bit data, and the data to be modulated is z, the initial frequency of the modulated segmented continuous frequency modulation wave is:

setting the starting frequency of each sub-carrier of a segmented continuous FM wave to be shifted up f₀Then the modulated signal is:

the invention carries out data modulation by changing the initial frequency of the signal, so that different nodes can use different segmented continuous frequency modulation waves to transmit data.

Based on any of the above embodiments, step S2 in the method specifically includes:

multiplying the modulated segmented continuous frequency modulation wave by the conjugate of the unmodulated segmented continuous frequency modulation wave to obtain a single-frequency signal;

carrying out Fourier transform on the single-frequency signals to obtain intensity distribution signals of the single-frequency signals on each frequency;

calculating to obtain the initial frequency of the de-spread signal based on the intensity distribution signal;

and obtaining the demodulated signal according to the initial frequency of the de-spread signal, the subcarrier bandwidth and the bit data of the preset digit.

Specifically, the signal demodulation steps provided by the present invention are as shown in fig. 3, and assuming that the bandwidth B, the signal period T, and the bit number p modulated by each segmented continuous fm wave are known at the receiving end, when the system receives the signal, the following method is used for demodulation:

firstly, the frequency is despread, the received signal is multiplied by the conjugate of the corresponding unmodulated segmented continuous frequency modulation wave to obtain a frequency f₀The single frequency signal of (a):

then, Fourier transform is carried out on the signals obtained by despreading to obtain the intensity distribution of the signals on each frequency;

further, according to the result obtained by Fourier transform, the frequency f with the highest de-spread signal intensity is calculated₀；

Finally, the modulated data is calculated according to the following formula:

the invention calculates the initial frequency of the signal after de-spreading and Fourier transform of the received signal and decodes data according to the initial frequency of the signal, thereby supporting low-power consumption, long-distance and high-concurrency communication.

The present invention provides a signal modulation and demodulation system for a segmented continuous frequency modulated wave, and the signal modulation and demodulation system for a segmented continuous frequency modulated wave described below and the signal modulation and demodulation method for a segmented continuous frequency modulated wave described above may be referred to correspondingly.

Fig. 4 is a schematic structural diagram of a signal modulation and demodulation system of a segmented continuous frequency modulated wave provided by the present invention, as shown in fig. 4, including: a modulation module 41 and a demodulation module 42; wherein:

the modulation module 41 is configured to adjust an initial frequency of a data signal to be modulated by a sending end to obtain a modulated segmented continuous frequency modulated wave; the demodulation module 42 is configured to perform despreading and fourier transform on the received modulated segmented continuous frequency modulated wave by the receiving end to obtain a despreading signal starting frequency, and obtain a demodulated signal from the despreading signal starting frequency.

According to the invention, a plurality of mutually orthogonal segmented continuous frequency modulation waves are constructed through the segmented continuous frequency modulation wave modulation signals, different nodes can use different segmented continuous frequency modulation waves to transmit data, and a receiving end can simultaneously decode signals from different nodes.

Based on the above embodiment, the system further includes an obtaining module 43, where the obtaining module 43 is configured to obtain the preset segmented continuous frequency modulation wave.

The obtaining module 43 is specifically configured to:

acquiring subcarriers with preset number, equal preset duration and non-overlapping frequency domains, wherein each subcarrier is a continuous frequency modulation wave;

setting a subcarrier period, a subcarrier bandwidth and a subcarrier starting frequency of each subcarrier, dividing the subcarrier period by the subcarrier bandwidth to obtain a frequency time-varying rate, and obtaining a signal representation of each subcarrier based on the subcarrier bandwidth, the subcarrier period, the frequency time-varying rate and the subcarrier starting frequency;

and obtaining digital permutation based on the preset number, obtaining the initial frequency of any subcarrier based on the digital permutation, and substituting all the initial frequencies of the subcarriers into the signal representation of each subcarrier to obtain the preset segmented continuous frequency modulation wave corresponding to the digital permutation.

Fig. 5 illustrates a physical structure diagram of an electronic device, which may include, as shown in fig. 5: a processor (processor)510, a communication interface (communication interface)520, a memory (memory)530 and a communication bus 540, wherein the processor 510, the communication interface 520 and the memory 530 communicate with each other via the communication bus 540. Processor 510 may invoke logic instructions in memory 530 to perform a method of signal modulation and demodulation of a segmented continuous frequency modulated wave, the method comprising: the method comprises the steps that a sending end obtains a modulated segmented continuous frequency modulation wave by adjusting the initial frequency of a data signal to be modulated; and the receiving terminal performs despreading and Fourier transform on the received modulated segmented continuous frequency modulation wave to obtain the initial frequency of a despread signal, and obtains a demodulated signal according to the initial frequency of the despread signal.

Furthermore, the logic instructions in the memory 530 may be implemented in the form of software functional units and stored in a computer readable storage medium when the software functional units are sold or used as independent products. 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: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

In another aspect, the present invention also provides a computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions which, when executed by a computer, enable the computer to perform a signal modulation and demodulation method for a segmented continuous frequency modulated wave provided by the above methods, the method comprising: the method comprises the steps that a sending end obtains a modulated segmented continuous frequency modulation wave by adjusting the initial frequency of a data signal to be modulated; and the receiving terminal performs despreading and Fourier transform on the received modulated segmented continuous frequency modulation wave to obtain the initial frequency of a despread signal, and obtains a demodulated signal according to the initial frequency of the despread signal.

In yet another aspect, the present invention also provides a non-transitory computer-readable storage medium having stored thereon a computer program which, when executed by a processor, is implemented to perform the signal modulation and demodulation method of the segmented continuous frequency modulated wave provided above, the method comprising: the method comprises the steps that a sending end obtains a modulated segmented continuous frequency modulation wave by adjusting the initial frequency of a data signal to be modulated; and the receiving terminal performs despreading and Fourier transform on the received modulated segmented continuous frequency modulation wave to obtain the initial frequency of a despread signal, and obtains a demodulated signal according to the initial frequency of the despread signal.

The above-described embodiments of the apparatus are merely illustrative, and 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 modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware. With this understanding in mind, the above-described technical solutions may be embodied in the form of a software product, which can be stored in a computer-readable storage medium such as ROM/RAM, magnetic disk, optical disk, etc., and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the methods described in the embodiments or some parts of the embodiments.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.