Carrier aggregation method and device

Abstract

The embodiment of the invention provides a carrier aggregation method and device, and relates to the technical field of communication, and the method comprises the steps: carrying out the power adjustment of original pilot frequency information in a signal on a subcarrier based on a power adjustment factor corresponding to the subcarrier, and obtaining an adjusted signal; carrying out carrier aggregation on the adjusted signal on each subcarrier to obtain a carrier aggregation signal; and sending the carrier aggregation signal to a receiver, so that the receiver carries out power adjustment on pilot frequency information in signals on each subcarrier in the carrier aggregation signal, original pilot frequency information corresponding to the pilot frequency information is obtained through reduction, and the adjusted carrier aggregation signal is demodulated. By applying the scheme provided by the embodiment of the invention, the power peak-to-average ratio of the carrier aggregation signal can be reduced.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of communication technology, and in particular, to a carrier aggregation method and device. Background Art

[0002] In mobile communication systems, in order to obtain better transmission quality, higher data transmission rate and spectrum efficiency, carrier aggregation is usually used to transmit signals. The carrier aggregation signal obtained by the carrier aggregation method is composed of multiple independently modulated subcarrier signals superimposed. When the initial phases of each subcarrier signal are the same, the carrier aggregation signal will be modulated to produce a larger instantaneous power peak, resulting in a higher peak-to-average power ratio. Since the dynamic range of the power amplifier in the signal transmitter is often limited, when the power amplifier is used to amplify the power of the carrier aggregation signal, the carrier aggregation signal with a higher peak-to-average power ratio is very easy to enter the nonlinear region of the power amplifier, resulting in nonlinear distortion of the carrier aggregation signal, causing obvious spectrum expansion interference and signal distortion, resulting in a serious decline in the performance of the communication system transmitting the carrier aggregation signal. Summary of the invention

[0003] The purpose of the embodiments of the present invention is to provide a carrier aggregation method and device to reduce the peak-to-average power ratio of carrier aggregation signals. The specific technical solution is as follows:

[0004] In a first aspect, an embodiment of the present invention provides a carrier aggregation method, which is applied to a transmitter. The method includes:

[0005] Based on the power adjustment factor corresponding to the subcarrier, power adjustment is performed on the original pilot information in the signal on the subcarrier to obtain an adjusted signal;

[0006] Carrier aggregation is performed on the adjusted signals on each subcarrier to obtain a carrier aggregation signal;

[0007] The carrier aggregation signal is sent to a receiver so that the receiver performs power adjustment on the pilot information in the signal on each subcarrier in the carrier aggregation signal, restores the original pilot information corresponding to the pilot information, and demodulates the adjusted carrier aggregation signal.

[0008] In one embodiment of the present invention, the power adjustment factor corresponding to the subcarrier is calculated in the following manner:

[0009] The subcarrier number is multiplied by the power adjustment coefficient to obtain a power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the number of each subcarrier is a different positive integer.

[0010] In one embodiment of the present invention, before performing carrier aggregation on the adjusted signals on each subcarrier to obtain the carrier aggregation signal, the method includes:

[0011] Filter the adjusted signal.

[0012] In a second aspect, an embodiment of the present invention provides a carrier aggregation method, which is applied to a receiver, and the method includes:

[0013] receiving a carrier aggregation signal sent by a transmitter, wherein the carrier aggregation signal is obtained by the transmitter performing carrier aggregation on the adjusted signals on each subcarrier, and the adjusted signal on the subcarrier is obtained by the transmitter performing power adjustment on original pilot information in the signal on the subcarrier based on a power adjustment factor corresponding to the subcarrier;

[0014] Based on the power adjustment factor corresponding to the subcarrier, power adjustment is performed on the pilot information in the signal on the subcarrier in the carrier aggregation signal to restore the original pilot information corresponding to the pilot information;

[0015] The adjusted carrier aggregation signal is demodulated.

[0016] In one embodiment of the present invention, the power adjustment factor corresponding to the subcarrier is calculated in the following manner:

[0017] The subcarrier number is multiplied by the power adjustment coefficient to obtain a power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the number of each subcarrier is a different positive integer.

[0018] In a third aspect, an embodiment of the present invention provides a carrier aggregation device, which is applied to a transmitter, and the device includes:

[0019] An adjustment module, configured to perform power adjustment on the original pilot information in the signal on the subcarrier based on the power adjustment factor corresponding to the subcarrier to obtain an adjusted signal;

[0020] an aggregation module, configured to perform carrier aggregation on the adjusted signals on each subcarrier to obtain a carrier aggregation signal;

[0021] A sending module is used to send the carrier aggregation signal to a receiver so that the receiver can adjust the power of the pilot information in the signal on each subcarrier in the carrier aggregation signal, restore the original pilot information corresponding to the pilot information, and demodulate the adjusted carrier aggregation signal.

[0022] In one embodiment of the present invention, the device further comprises:

[0023] The first calculation module is used to multiply the serial number of the subcarrier by the power adjustment coefficient to obtain the power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the serial number of each subcarrier is a different positive integer.

[0024] In one embodiment of the present invention, the device further comprises:

[0025] The filtering module is used to filter the adjusted signal.

[0026] In a fourth aspect, an embodiment of the present invention provides a carrier aggregation device, applied to a receiver, the device comprising:

[0027] A receiving module, configured to receive a carrier aggregation signal sent by a transmitter, wherein the carrier aggregation signal is obtained by the transmitter performing carrier aggregation on the adjusted signals on each subcarrier, and the adjusted signal on the subcarrier is obtained by the transmitter performing power adjustment on the original pilot information in the signal on the subcarrier based on the power adjustment factor corresponding to the subcarrier;

[0028] A restoration module, configured to perform power adjustment on the pilot information in the signal on the subcarrier in the carrier aggregation signal based on the power adjustment factor corresponding to the subcarrier, and restore the original pilot information corresponding to the pilot information;

[0029] The demodulation module is used to demodulate the adjusted carrier aggregation signal.

[0030] In one embodiment of the present invention, the device further comprises:

[0031] The second calculation module is used to multiply the subcarrier number by the power adjustment coefficient to obtain the power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the sequence numbers of each subcarrier are different positive integers.

[0032] In a fifth aspect, an embodiment of the present invention provides a transmitter, including a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus;

[0033] Memory, used to store computer programs;

[0034] The processor is used to implement any method step of the first aspect when executing the program stored in the memory.

[0035] In a sixth aspect, an embodiment of the present invention provides a receiver, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus;

[0036] Memory, used to store computer programs;

[0037] The processor is used to implement any method step of the second aspect when executing the program stored in the memory.

[0038] In a seventh aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method steps of any one of the first aspect or the second aspect are implemented.

[0039] Beneficial effects of the embodiments of the present invention:

[0040] An embodiment of the present invention provides a carrier aggregation method, which includes: based on a power adjustment factor corresponding to a subcarrier, power adjusting the original pilot information in the signal on the subcarrier to obtain an adjusted signal; carrier aggregating the adjusted signals on each subcarrier to obtain a carrier aggregation signal; sending the carrier aggregation signal to a receiver so that the receiver performs power adjustment on the pilot information in the signal on each subcarrier in the carrier aggregation signal, restores the original pilot information corresponding to the pilot information, and demodulates the adjusted carrier aggregation signal.

[0041] As can be seen from the above, in the scheme provided by the embodiment of the present invention, for any subcarrier participating in carrier aggregation, the power of the original pilot information in the signal on the subcarrier is adjusted based on the power adjustment factor of the subcarrier to obtain the adjusted signal. The power of the adjusted signals on each subcarrier is different. It can be seen from the basic principle of signal modulation that the phases of signals with different powers after adjustment are different. On this basis, the adjusted signals on each subcarrier are carrier aggregated, and the modulation will not produce a large instantaneous power peak due to the same phase of the signals on each subcarrier, thereby reducing the power peak-to-average ratio of the carrier aggregation signal. In addition, by applying the scheme provided by the embodiment of the present invention, it is only necessary to adjust the power of the original pilot information in the signal on each subcarrier. The complexity of the design and implementation is not high. At the same time, it does not involve reserving subcarriers, but all subcarriers in the received carrier aggregation signal are processed at the receiver, so the spectrum efficiency of the signal after carrier aggregation will not be lost. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can also be obtained based on these drawings.

[0043] Figure 1A schematic diagram of a flow chart of a first carrier aggregation method provided in an embodiment of the present invention;

[0044] Figure 2 A schematic diagram of a frame structure of a signal on a subcarrier participating in carrier aggregation provided by an embodiment of the present invention;

[0045] Figure 3 A schematic diagram of a flow chart of a second carrier aggregation method provided in an embodiment of the present invention;

[0046] Figure 4 A schematic diagram of a flow chart of a subcarrier pilot information adjustment method provided by an embodiment of the present invention;

[0047] Figure 5 A schematic diagram of symbol constellation points of a carrier aggregation signal provided in an embodiment of the present invention;

[0048] Figure 6 A schematic diagram of a signal amplitude before adjustment of a carrier aggregation signal provided by an embodiment of the present invention;

[0049] Figure 7 A schematic diagram of a signal amplitude after adjustment of a carrier aggregation signal provided by an embodiment of the present invention;

[0050] Figure 8 A schematic diagram of a flow chart of a third carrier aggregation method provided in an embodiment of the present invention;

[0051] Fig. 9 A schematic structural diagram of a first carrier aggregation device provided by an embodiment of the present invention;

[0052] Fig.10 A schematic structural diagram of a second carrier aggregation device provided by an embodiment of the present invention;

[0053] Fig.11 A schematic diagram of the structure of a transmitter provided by an embodiment of the present invention;

[0054] Fig.12 A structural schematic diagram of a receiver provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field based on the present invention belong to the scope of protection of the present invention.

[0056] In a mobile communication system, a carrier aggregation signal obtained by using a carrier aggregation method is composed of a plurality of independently modulated subcarrier signals superimposed. When the initial phases of the subcarrier signals are the same, the carrier aggregation signal will be modulated to produce a larger instantaneous power peak, resulting in a higher peak-to-average power ratio. Carrier aggregation signals with a higher peak-to-average power ratio are very easy to enter the nonlinear region of the power amplifier, resulting in nonlinear distortion of the carrier aggregation signal, causing significant spectrum expansion interference and signal distortion, resulting in a serious degradation in the performance of the communication system transmitting the carrier aggregation signal. In the related art, a method for reducing the peak-to-average power ratio of a carrier aggregation signal is based on a frame structure, and different pilot information sequences are involved for signals on different subcarriers. However, as the number of subcarriers increases, the design and implementation complexity of this method is relatively large. In the related art, another method for reducing the peak-to-average power ratio of a carrier aggregation signal is to reduce the correlation of signals on different subcarriers by reserving subcarriers, but this method is strongly related to the position of the reserved subcarriers, and some subcarriers with larger signal power will not be processed at the receiver, thereby losing the spectrum efficiency of the carrier aggregation signal.

[0057] In order to solve the above problems, the embodiments of the present invention provide a carrier aggregation method and device, which are described in detail below.

[0058] First, a carrier aggregation method provided by an embodiment of the present invention is described.

[0059] See also Figure 1 , is a flow chart of a first carrier aggregation method provided in an embodiment of the present invention. The method is applied to a transmitter, and the method includes the following steps S101 to S103.

[0060] Step S101: Based on the power adjustment factor corresponding to the subcarrier, power adjustment is performed on the original pilot information in the signal on the subcarrier to obtain an adjusted signal.

[0061] like Figure 2 As shown, it is a schematic diagram of a frame structure of a signal on a subcarrier participating in carrier aggregation, from Figure 2 It can be seen that the signal on the subcarrier includes pilot information and data information. In the embodiment of the present invention, the pilot information in the signal on the subcarrier that has not been adjusted by the power adjustment factor is referred to as the original pilot information.

[0062] The pilot information is a signal sent for the purpose of measurement or monitoring, and the data information is a data signal actually transmitted in the signal.

[0063] Before power adjustment is performed on the above original pilot information, the original pilot information of the subcarrier needs to be identified first. Specifically, the original pilot information of the subcarrier is at a predetermined time domain position in the signal on the subcarrier. By simply obtaining the time domain position information of the original pilot information of the subcarrier, the original pilot information of the subcarrier can be identified at the corresponding time domain position in the signal on the subcarrier.

[0064] In an embodiment of the present invention, for any subcarrier participating in carrier aggregation, the original pilot information of the subcarrier is adjusted using the power adjustment factor corresponding to the subcarrier, that is, for any subcarrier, the adjusted pilot information is obtained based on the power adjustment factor corresponding to the subcarrier multiplied by the original pilot information in the signal on the subcarrier. After the power adjustment factor is multiplied by the original pilot information, the power and phase of the original pilot information will be changed at the same time. Based on the power adjustment factor corresponding to each subcarrier, the adjusted pilot information corresponding to different subcarriers is different, so that the power and phase of the pilot information in each subcarrier participating in carrier aggregation are different, and then the phase of the signal in each subcarrier participating in carrier aggregation is different. Among them, the power adjustment factors of each subcarrier can be different, or partially the same.

[0065] In addition, after the power adjustment is performed on the original pilot information in the signal on the subcarrier, the signal on the subcarrier is called an adjusted signal.

[0066] In one embodiment of the present invention, the power adjustment factors corresponding to different subcarriers may be a series of different values ​​that are set in advance.

[0067] In another embodiment of the present invention, the power adjustment factor corresponding to the subcarrier can be calculated by following step A.

[0068] Step A: Multiply the subcarrier number by the power adjustment coefficient to obtain the power adjustment factor corresponding to the subcarrier.

[0069] The power adjustment coefficient is calculated based on the total number of subcarriers, and the serial number of each subcarrier is a different positive integer.

[0070] In an embodiment of the present invention, the total number of subcarriers may be a positive integer N, and the power adjustment coefficient may be any positive value obtained based on the positive integer N. Exemplarily, the power adjustment coefficient may be the arithmetic square root of the reciprocal of the positive integer N, or the arithmetic square root of the reciprocal of the square of the positive integer N, or one tenth or one hundredth of the positive integer N, etc. The embodiment of the present invention does not limit the specific method of obtaining the power adjustment coefficient based on the total number of subcarriers.

[0071] The sequence number of each subcarrier may be a continuous positive integer starting from 1, or may be any other series of positive integers, as long as the sequence number of each subcarrier is different.

[0072] Since the serial numbers of each subcarrier are different positive integers, for any subcarrier, after multiplying the serial number of the subcarrier by the above-mentioned power adjustment coefficient, the power adjustment factor corresponding to the subcarrier obtained is different from the power adjustment factors of other subcarriers participating in carrier aggregation, that is, the power adjustment factors of each subcarrier participating in carrier aggregation calculated in an embodiment of the present invention are different.

[0073] In one embodiment of the present invention, for any subcarrier participating in carrier aggregation, the subcarrier is numbered i and is referred to as subcarrier i. The signal on subcarrier i can be represented as: sig i ={p0, p1, ..., p m , s0, s1, …, s n}, where sig i is the signal on subcarrier i, {p0, p1, ..., p m} is the pilot information, {s0, s1, ..., s n} is data information, where sig i The arrangement order of each information contained in the set does not represent the arrangement order of each information in the signal on subcarrier i.

[0074] The power adjustment factor a of subcarrier i is sqrt(1 / N)*i, where “*” represents multiplication, N is the total number of subcarriers participating in carrier aggregation, and i=1, 2, …, N.

[0075] Then the power adjustment method for the pilot information in the signal on subcarrier i can be to multiply the pilot information by the power adjustment factor a, and the adjusted signal on subcarrier i is sig′ i ={p0*a, p1*a, …, p m *a,s0,s1,…,s n}.

[0076] Step S102: Carrier aggregation is performed on the adjusted signals on each subcarrier to obtain a carrier aggregation signal.

[0077] After the original pilot information in the signal on each subcarrier participating in carrier aggregation is adjusted as in step S101, the phases of the adjusted signals on each subcarrier are different. In this case, the adjusted signals on each subcarrier can be carrier aggregated to obtain a carrier aggregation signal with a lower peak-to-average power ratio.

[0078] In one embodiment of the present invention, the obtained carrier aggregation signal can be expressed as: Among them, out_sig is the carrier aggregation signal.

[0079] Step S103: Send the carrier aggregation signal to the receiver so that the receiver adjusts the power of the pilot information in the signal on each subcarrier in the carrier aggregation signal, restores the original pilot information corresponding to the pilot information, and demodulates the adjusted carrier aggregation signal.

[0080] After obtaining a carrier aggregation signal with a lower power peak-to-average ratio through step S102, the carrier aggregation signal is sent to the receiver. The pilot information in the signal on any subcarrier in the carrier aggregation signal received by the receiver is the original pilot information of the subcarrier after power adjustment. The receiver needs to power adjust the pilot information in the signal on the subcarrier to restore the original pilot information corresponding to the pilot information.

[0081] Exemplarily, if the power adjustment method for the original pilot information is to multiply the power adjustment factor corresponding to the subcarrier by the original pilot information, the receiver obtains the power adjustment factor in the manner described in step S101, and then divides the pilot information in the signal on the received subcarrier by the power adjustment factor to obtain the original pilot information. After obtaining the original pilot information of the signal on each subcarrier in the received carrier aggregation signal, the receiver obtains the adjusted carrier aggregation signal and demodulates the adjusted carrier aggregation signal.

[0082] Specifically, for any subcarrier in the above-mentioned carrier aggregation signal received by the receiver, the pilot information in the signal on the subcarrier is at the above-mentioned predetermined time domain position in the signal on the subcarrier. The receiver can identify the pilot information of the subcarrier based on the time domain position information, and then adjust the power of the identified pilot information to restore the original pilot information.

[0083] As can be seen from the above, in the scheme provided by the embodiment of the present invention, for any subcarrier participating in carrier aggregation, the power of the original pilot information in the signal on the subcarrier is adjusted based on the power adjustment factor of the subcarrier to obtain the adjusted signal. The power of the adjusted signals on each subcarrier is different. It can be seen from the basic principle of signal modulation that the phases of signals with different powers after adjustment are different. On this basis, the adjusted signals on each subcarrier are carrier aggregated, and the modulation will not produce a large instantaneous power peak due to the same phase of the signals on each subcarrier, thereby reducing the power peak-to-average ratio of the carrier aggregation signal. In addition, by applying the scheme provided by the embodiment of the present invention, it is only necessary to adjust the power of the original pilot information in the signal on each subcarrier. The complexity of the design and implementation is not high. At the same time, it does not involve reserving subcarriers, but all subcarriers in the received carrier aggregation signal are processed at the receiver, so the spectrum efficiency of the signal after carrier aggregation will not be lost.

[0084] Specifically, the carrier aggregation signal in the embodiment of the present invention may be a burst modulation signal, that is, a carrier aggregation signal that is sent non-periodically; the transmitter and receiver in the embodiment of the present invention may be used in a satellite communication system, that is, the above-mentioned transmitter and receiver may be installed on a satellite.

[0085] If the subcarriers participating in carrier aggregation have some cluttered signals, the quality of the formed carrier aggregation signal will be poor. Therefore, the embodiment of the present invention provides Figure 3 The embodiment shown.

[0086] See also Figure 3 , is a flow chart of a second carrier aggregation method provided by an embodiment of the present invention, the method is applied to a transmitter, and Figure 1 Compared with the embodiment shown, before step S102, the following step S104 is also included.

[0087] Step S104: filtering the adjusted signal.

[0088] Specifically, for any subcarrier participating in carrier aggregation, after obtaining the adjustment signal on the subcarrier in the manner in step S101, the adjustment signal on the subcarrier is subjected to shaping filtering to effectively remove the clutter signal in the adjustment signal on the subcarrier. The specific manner of performing shaping filtering is prior art and will not be described in detail here.

[0089] In one embodiment of the present invention, the adjusted signal sig′ on subcarrier i is i Perform shaping filtering, and record the adjusted signal on subcarrier i after shaping filtering as sig″ i Exemplarily, the shaping filter may be performed by 4 times upsampling.

[0090] It can be seen from the above that in the solution provided by the embodiment of the present invention, the adjustment signal on each subcarrier is filtered, which can effectively remove the clutter signal in the adjustment signal on each subcarrier, thereby obtaining a carrier aggregation signal with higher quality.

[0091] See also Figure 4 , is a flow chart of a subcarrier pilot information adjustment method provided in an embodiment of the present invention. The method is applied to a transmitter, and the method includes the following steps S201 to S206.

[0092] Step S201: Determine the total number N of subcarriers.

[0093] Specifically, firstly, the value of the total number N of subcarriers participating in carrier aggregation is determined.

[0094] Step S202: Determine whether the subcarrier number is less than or equal to N.

[0095] In the embodiment of the present invention, the sequence number of each subcarrier participating in carrier aggregation can be set to a continuous positive integer starting from 1, and each subcarrier is traversed in turn. After each execution of steps S202-S205, 1 is added to the sequence number of the current subcarrier, and step S202 is executed again. If the value of the sequence number of the current subcarrier is less than or equal to N, the subcarrier is considered to be a subcarrier participating in carrier aggregation, and step S203 is executed; if the value of the sequence number of the subcarrier is greater than N, it is considered that the subcarriers participating in carrier aggregation have all been power adjusted, and step S206 is executed.

[0096] Step S203: Determine whether the identified information is pilot information in the signal on the subcarrier.

[0097] For any subcarrier participating in carrier aggregation, it is necessary to identify the pilot information in the signal on the subcarrier. Since the pilot information of the subcarrier is located at a predetermined time domain position in the signal on the subcarrier, it is possible to determine whether the identified information is the pilot information in the signal on the subcarrier according to the time domain position of the signal on the subcarrier. After determining that the identified information is the pilot information in the signal on the subcarrier, step S204 is executed, otherwise step S206 is executed.

[0098] Step S204: perform power adjustment on the identified pilot information.

[0099] Specifically, after the pilot information in the subcarrier signal is identified, the power of the pilot information is adjusted in the manner described in step S101.

[0100] Step S205: Determine the adjusted signal on the subcarrier.

[0101] After the power adjustment is performed on the pilot information in the signal on the subcarrier, the signal on the subcarrier is called an adjusted signal.

[0102] Step S206: Determine the adjusted signal on each subcarrier participating in carrier aggregation.

[0103] In an embodiment of the present invention, the serial numbers of each subcarrier participating in carrier aggregation are set to continuous positive integers starting from 1. After the pilot information in the signals on N subcarriers with serial numbers from 1 to N are all power adjusted, it is determined that the adjusted signals on each subcarrier participating in carrier aggregation are obtained.

[0104] In one embodiment of the present invention, for any subcarrier participating in carrier aggregation, the subcarrier is numbered i and is referred to as subcarrier i. The signal on subcarrier i can be represented as: sig i ={p0, p1, ..., p m , s0, s1, …, s n}, the power adjustment factor of subcarrier i is a=sqrt(1 / N)*i, and the adjusted signal on subcarrier i is sig′ i ={p0*a, p1*a, …, p m *a,s0,s1,…,s n}.

[0105] Afterwards, the adjusted signal sig′ on subcarrier i is i Perform shaping filtering to obtain the adjusted signal sig″ on the subcarrier i after shaping filtering i Among them, the shaping filter method can be 4 times upsampling.

[0106] After shaping and filtering the adjustment signal on each subcarrier, the carrier aggregation signal finally obtained can be expressed as:

[0107] Exemplarily, in the embodiment of the present invention, the value of N is 50, and after the adjustment signal on each subcarrier is shaped and filtered, the relevant parameters involved in the carrier aggregation process are obtained as shown in the following Table 1. Referring to Table 1, an example table of relevant parameters in a carrier aggregation process provided in an embodiment of the present invention.

[0108] Table 1

[0109] parameter Parameter Value Signal Type DTB Voice Signal-to-Noise Ratio 10dB Modulation QPSK Encoding Type Turbo Number of carriers 50

[0110] In Table 1, the signal type of the carrier aggregation signal is DTB (Digital Terrestrial Broadcasting) voice. Based on each subcarrier, the modulation mode of the carrier aggregation signal is QPSK (Quadrature Phase Shift Keying), and the coding type of the carrier aggregation signal is Turbo coding, which refers to parallel cascade convolution coding. Specifically, the process of obtaining the carrier aggregation signal also involves CRC (Cyclic Redundancy Check) technology. Specifically, the modulation mode and coding type involved in the process of obtaining the carrier aggregation signal are all existing technologies and will not be described here. It should be noted that the parameter values ​​in Table 1 are all examples, that is, the signal type, signal-to-noise ratio, modulation mode, coding type and number of carriers in Table 1 can be set according to actual conditions.

[0111] Specifically, based on the parameter values ​​in Table 1, after the pilot information in the signal on each subcarrier is power adjusted using the power adjustment factor, the symbol constellation point diagram of the carrier aggregation signal is obtained as follows: Figure 5 As shown. The value of each symbol constellation point contains a real part and an imaginary part. Figure 5 In the figure, the horizontal axis is the value of the real part, and the vertical axis is the value of the imaginary part.

[0112] See also Figure 6 , is a schematic diagram of a signal amplitude before a carrier aggregation signal is adjusted according to an embodiment of the present invention, Figure 6 The horizontal axis is the number of sampling points, and the vertical axis is the signal power. Figure 6 It can be seen from the figure that when the pilot information in the signal on each subcarrier is not power adjusted by the power adjustment factor, the carrier aggregation signal has a higher power peak, and the power peak of the carrier aggregation signal is relatively high.

[0113] See also Figure 7 , is a schematic diagram of a signal amplitude after a carrier aggregation signal is adjusted according to an embodiment of the present invention, Figure 7 The horizontal axis is the number of sampling points, and the vertical axis is the signal power. Figure 7 It can be seen that after the pilot information in the signal on each subcarrier is power adjusted by the power adjustment factor, the carrier aggregation signal does not have a high power peak, and the power peak of the carrier aggregation signal is relatively low.

[0114] contrast Figure 6 and Figure 7 It can be seen that by applying the solution provided by the embodiment of the present invention, after the pilot information in the signal on each subcarrier is adjusted by the power adjustment factor, the peak-to-average ratio of the carrier aggregation signal is effectively reduced. In addition, it should be noted that Figure 6 and Figure 7 The signal type, signal-to-noise ratio, modulation method, coding type and number of carriers involved in the carrier aggregation signal are shown in Table 1.

[0115] Corresponding to the aforementioned carrier aggregation method applied to a transmitter, an embodiment of the present invention further provides a carrier aggregation method applied to a receiver.

[0116] See also Figure 8 , is a flow chart of a third carrier aggregation method provided in an embodiment of the present invention. The method is applied to a receiver, and the method includes the following steps S801 to S803.

[0117] Step S801: Receive a carrier aggregation signal sent by a transmitter.

[0118] Among them, the above-mentioned carrier aggregation signal is obtained by the above-mentioned transmitter performing carrier aggregation on the adjusted signals on each subcarrier, and the adjusted signal on the subcarrier is obtained after the above-mentioned transmitter performs power adjustment on the original pilot information in the signal on the subcarrier based on the power adjustment factor corresponding to the subcarrier.

[0119] Step S802: Based on the power adjustment factor corresponding to the subcarrier, power adjustment is performed on the pilot information in the signal on the subcarrier in the carrier aggregation signal to restore the original pilot information corresponding to the pilot information.

[0120] Since at the transmitter, the transmitter uses the power adjustment factor corresponding to the subcarrier to perform mathematical operations with its original pilot information to obtain the adjusted pilot information, therefore, for the subcarrier of the received carrier aggregation signal, the receiver uses the power adjustment factor corresponding to the subcarrier to perform operations inverse to the above mathematical operations with its pilot information to restore the original pilot information corresponding to the pilot information. Exemplarily, for any subcarrier, the transmitter uses the power adjustment factor corresponding to the subcarrier to multiply the original pilot information of the subcarrier to obtain the adjusted pilot information. After obtaining the subcarrier, the receiver divides the current pilot information of the subcarrier by the power adjustment factor corresponding to the subcarrier to restore the original pilot information of the subcarrier.

[0121] In one embodiment of the present invention, the power adjustment factors corresponding to different subcarriers may be a series of different numbers set in advance.

[0122] In another embodiment of the present invention, the power adjustment factor corresponding to the subcarrier may be calculated by following step B.

[0123] Step B: Multiply the subcarrier number by the power adjustment coefficient to obtain the power adjustment factor corresponding to the subcarrier.

[0124] The power adjustment coefficient is calculated based on the total number of subcarriers, and the serial number of each subcarrier is a different positive integer.

[0125] Specifically, the method of obtaining the power adjustment factor in step B may refer to the content described in the above step A, which will not be repeated here.

[0126] Step S803: demodulate the adjusted carrier aggregation signal.

[0127] Specifically, the transmitter performs carrier aggregation on the adjusted signals on each subcarrier based on the relevant modulation and coding technology to obtain a carrier aggregation signal. After executing step S802, the receiver uses a demodulation technology corresponding to the modulation and coding technology used by the transmitter to demodulate the carrier aggregation signal. Specifically, the above demodulation technology is an existing technology and is not described in detail here.

[0128] As can be seen from the above, in the scheme provided by the embodiment of the present invention, for any subcarrier participating in carrier aggregation, the power of the original pilot information in the signal on the subcarrier is adjusted based on the power adjustment factor of the subcarrier to obtain the adjusted signal. The power of the adjusted signals on each subcarrier is different. It can be seen from the basic principle of signal modulation that the phases of signals with different powers after adjustment are different. On this basis, the adjusted signals on each subcarrier are carrier aggregated, and the modulation will not produce a large instantaneous power peak due to the same phase of the signals on each subcarrier, thereby reducing the power peak-to-average ratio of the carrier aggregation signal. In addition, by applying the scheme provided by the embodiment of the present invention, it is only necessary to adjust the power of the original pilot information in the signal on each subcarrier. The complexity of the design and implementation is not high. At the same time, it does not involve reserving subcarriers, but all subcarriers in the received carrier aggregation signal are processed at the receiver, so the spectrum efficiency of the signal after carrier aggregation will not be lost.

[0129] Corresponding to the aforementioned carrier aggregation method applied to a transmitter, an embodiment of the present invention further provides a carrier aggregation device.

[0130] See also Fig. 9 , is a structural diagram of a first carrier aggregation device provided by an embodiment of the present invention, the device is applied to a transmitter, and the device includes:

[0131] An adjustment module 901 is used to adjust the power of the original pilot information in the signal on the subcarrier based on the power adjustment factor corresponding to the subcarrier to obtain an adjusted signal;

[0132] Aggregation module 902, configured to perform carrier aggregation on the adjusted signals on each subcarrier to obtain a carrier aggregation signal;

[0133] The sending module 903 is used to send the above-mentioned carrier aggregation signal to the receiver, so that the above-mentioned receiver adjusts the power of the pilot information in the signal on each subcarrier in the above-mentioned carrier aggregation signal, restores the original pilot information corresponding to the pilot information, and demodulates the adjusted carrier aggregation signal.

[0134] As can be seen from the above, in the scheme provided by the embodiment of the present invention, for any subcarrier participating in carrier aggregation, the power of the original pilot information in the signal on the subcarrier is adjusted based on the power adjustment factor of the subcarrier to obtain the adjusted signal. The power of the adjusted signals on each subcarrier is different. It can be seen from the basic principle of signal modulation that the phases of signals with different powers after adjustment are different. On this basis, the adjusted signals on each subcarrier are carrier aggregated, and the modulation will not produce a large instantaneous power peak due to the same phase of the signals on each subcarrier, thereby reducing the power peak-to-average ratio of the carrier aggregation signal. In addition, by applying the scheme provided by the embodiment of the present invention, it is only necessary to adjust the power of the original pilot information in the signal on each subcarrier. The complexity of the design and implementation is not high. At the same time, it does not involve reserving subcarriers, but all subcarriers in the received carrier aggregation signal are processed at the receiver, so the spectrum efficiency of the signal after carrier aggregation will not be lost.

[0135] In one embodiment of the present invention, the above device further includes:

[0136] The first calculation module 904 is used to multiply the subcarrier number by the power adjustment coefficient to obtain the power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the sequence number of each subcarrier is a different positive integer.

[0137] In one embodiment of the present invention, the above device further includes:

[0138] The filtering module 905 is used to filter the adjusted signal.

[0139] It can be seen from the above that in the solution provided by the embodiment of the present invention, the adjustment signal on each subcarrier is filtered, which can effectively remove the clutter signal in the adjustment signal on each subcarrier, thereby obtaining a carrier aggregation signal with higher quality.

[0140] Corresponding to the aforementioned carrier aggregation method applied to a receiver, an embodiment of the present invention further provides a carrier aggregation device.

[0141] See also Fig.10 , is a structural diagram of a second carrier aggregation device provided by an embodiment of the present invention, the device is applied to a receiver, and the device includes:

[0142] The receiving module 1001 is used to receive a carrier aggregation signal sent by a transmitter, wherein the carrier aggregation signal is obtained by the transmitter performing carrier aggregation on the adjusted signals on each subcarrier, and the adjusted signal on the subcarrier is obtained by the transmitter performing power adjustment on the original pilot information in the signal on the subcarrier based on the power adjustment factor corresponding to the subcarrier;

[0143] The restoration module 1002 is used to perform power adjustment on the pilot information in the signal on the subcarrier in the carrier aggregation signal based on the power adjustment factor corresponding to the subcarrier, and restore the original pilot information corresponding to the pilot information;

[0144] The demodulation module 1003 is used to demodulate the adjusted carrier aggregation signal.

[0145] As can be seen from the above, in the scheme provided by the embodiment of the present invention, for any subcarrier participating in carrier aggregation, the power of the original pilot information in the signal on the subcarrier is adjusted based on the power adjustment factor of the subcarrier to obtain the adjusted signal. The power of the adjusted signals on each subcarrier is different. It can be seen from the basic principle of signal modulation that the phases of signals with different powers after adjustment are different. On this basis, the adjusted signals on each subcarrier are carrier aggregated, and the modulation will not produce a large instantaneous power peak due to the same phase of the signals on each subcarrier, thereby reducing the power peak-to-average ratio of the carrier aggregation signal. In addition, by applying the scheme provided by the embodiment of the present invention, it is only necessary to adjust the power of the original pilot information in the signal on each subcarrier. The complexity of the design and implementation is not high. At the same time, it does not involve reserving subcarriers, but all subcarriers in the received carrier aggregation signal are processed at the receiver, so the spectrum efficiency of the signal after carrier aggregation will not be lost.

[0146] In one embodiment of the present invention, the above device further includes:

[0147] The second calculation module 1004 is used to multiply the subcarrier number by the power adjustment coefficient to obtain the power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the sequence number of each subcarrier is a different positive integer.

[0148] See also Fig.11 , is a schematic diagram of the structure of a transmitter provided by an embodiment of the present invention, including a processor 1101, a communication interface 1102, a memory 1103 and a communication bus 1104, wherein the processor 1101, the communication interface 1102, and the memory 1103 communicate with each other through the communication bus 1104;

[0149] Memory 1103, used for storing computer programs;

[0150] The processor 1101 is configured to implement any one of the steps of the aforementioned carrier aggregation method applied to the transmitter when executing the program stored in the memory 1103.

[0151] As can be seen from the above, in the scheme provided by the embodiment of the present invention, for any subcarrier participating in carrier aggregation, the power of the original pilot information in the signal on the subcarrier is adjusted based on the power adjustment factor of the subcarrier to obtain the adjusted signal. The power of the adjusted signals on each subcarrier is different. It can be seen from the basic principle of signal modulation that the phases of signals with different powers after adjustment are different. On this basis, the adjusted signals on each subcarrier are carrier aggregated, and the modulation will not produce a large instantaneous power peak due to the same phase of the signals on each subcarrier, thereby reducing the power peak-to-average ratio of the carrier aggregation signal. In addition, by applying the scheme provided by the embodiment of the present invention, it is only necessary to adjust the power of the original pilot information in the signal on each subcarrier. The complexity of the design and implementation is not high. At the same time, it does not involve reserving subcarriers, but all subcarriers in the received carrier aggregation signal are processed at the receiver, so the spectrum efficiency of the signal after carrier aggregation will not be lost.

[0152] See also Fig.12 , is a structural diagram of a receiver provided by an embodiment of the present invention, including a processor 1201, a communication interface 1202, a memory 1203 and a communication bus 1204, wherein the processor 1201, the communication interface 1202, and the memory 1203 communicate with each other through the communication bus 1204;

[0153] Memory 1203, used for storing computer programs;

[0154] The processor 1201 is configured to implement any step of the aforementioned carrier aggregation method applied to a receiver when executing the program stored in the memory 1203 .

[0155] As can be seen from the above, in the scheme provided by the embodiment of the present invention, for any subcarrier participating in carrier aggregation, the power of the original pilot information in the signal on the subcarrier is adjusted based on the power adjustment factor of the subcarrier to obtain the adjusted signal. The power of the adjusted signals on each subcarrier is different. It can be seen from the basic principle of signal modulation that the phases of signals with different powers after adjustment are different. On this basis, the adjusted signals on each subcarrier are carrier aggregated, and the modulation will not produce a large instantaneous power peak due to the same phase of the signals on each subcarrier, thereby reducing the power peak-to-average ratio of the carrier aggregation signal. In addition, by applying the scheme provided by the embodiment of the present invention, it is only necessary to adjust the power of the original pilot information in the signal on each subcarrier. The complexity of the design and implementation is not high. At the same time, it does not involve reserving subcarriers, but all subcarriers in the received carrier aggregation signal are processed at the receiver, so the spectrum efficiency of the signal after carrier aggregation will not be lost.

[0156] The communication bus mentioned in the above electronic device can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The communication bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus.

[0157] The communication interface is used for communication between the above electronic device and other devices.

[0158] The memory may include a random access memory (RAM) or a non-volatile memory (NVM), such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the aforementioned processor.

[0159] The above-mentioned processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0160] In another embodiment of the present invention, a computer-readable storage medium is provided, in which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above-mentioned carrier aggregation methods are implemented.

[0161] When the computer program stored in the computer-readable storage medium provided by the embodiment of the present invention is applied to perform carrier aggregation, for any subcarrier participating in carrier aggregation, the power of the original pilot information in the signal on the subcarrier is adjusted based on the power adjustment factor of the subcarrier to obtain the adjusted signal. The power of the adjusted signals on each subcarrier is different. It can be seen from the basic principle of signal modulation that the phases of signals with different powers after adjustment are different. On this basis, the adjusted signals on each subcarrier are carrier aggregated, and a large instantaneous power peak will not be generated due to the same phase of the signals on each subcarrier, thereby reducing the power peak-to-average ratio of the carrier aggregation signal. In addition, when the scheme provided by the embodiment of the present invention is applied, it is only necessary to adjust the power of the original pilot information in the signal on each subcarrier. The complexity of the design and implementation is not high. At the same time, it does not involve reserving subcarriers, but all subcarriers in the received carrier aggregation signal are processed at the receiver, so the spectrum efficiency of the signal after carrier aggregation will not be lost.

[0162] In another embodiment of the present invention, a computer program product including instructions is provided. When the computer program product is run on a computer, the computer executes any carrier aggregation method in the above embodiments.

[0163] When the computer program product provided by the embodiment of the present invention is applied to perform carrier aggregation, for any subcarrier participating in the carrier aggregation, the power of the original pilot information in the signal on the subcarrier is adjusted based on the power adjustment factor of the subcarrier to obtain the adjusted signal. The power of the adjusted signals on each subcarrier is different. It can be seen from the basic principle of signal modulation that the phases of signals with different powers after adjustment are different. On this basis, the adjusted signals on each subcarrier are carrier aggregated, and the modulation will not produce a large instantaneous power peak due to the same phase of the signals on each subcarrier, thereby reducing the power peak-to-average ratio of the carrier aggregation signal. In addition, when the scheme provided by the embodiment of the present invention is applied, it is only necessary to adjust the power of the original pilot information in the signal on each subcarrier. The complexity of the design and implementation is not high. At the same time, it does not involve reserving subcarriers, but all subcarriers in the received carrier aggregation signal are processed at the receiver, so the spectrum efficiency of the signal after carrier aggregation will not be lost.

[0164] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state hard disk Solid State Disk (SSD)), etc.

[0165] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0166] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device, transmitter, receiver, computer-readable storage medium, and computer program product embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0167] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A carrier aggregation method, characterized in that: Applied to a transmitter, the method comprises: Based on the power adjustment factor corresponding to the subcarrier, power adjustment is performed on the original pilot information in the signal on the subcarrier to obtain an adjusted signal; Carrier aggregation is performed on the adjusted signals on each subcarrier to obtain a carrier aggregation signal; The carrier aggregation signal is sent to a receiver so that the receiver performs power adjustment on the pilot information in the signal on each subcarrier in the carrier aggregation signal, restores the original pilot information corresponding to the pilot information, and demodulates the adjusted carrier aggregation signal.

2. The method according to claim 1, characterized in that The power adjustment factor corresponding to the subcarrier is calculated in the following way: The subcarrier number is multiplied by the power adjustment coefficient to obtain a power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the sequence numbers of the subcarriers are different positive integers.

3. The method according to claim 1 or 2, characterized in that: Before performing carrier aggregation on the adjusted signals on the respective subcarriers to obtain the carrier aggregation signal, the method includes: Filter the adjusted signal.

4. A carrier aggregation method, characterized in that: Applied to a receiver, the method comprises: receiving a carrier aggregation signal sent by a transmitter, wherein the carrier aggregation signal is obtained by the transmitter performing carrier aggregation on the adjusted signals on each subcarrier, and the adjusted signal on the subcarrier is obtained by the transmitter performing power adjustment on original pilot information in the signal on the subcarrier based on a power adjustment factor corresponding to the subcarrier; Based on the power adjustment factor corresponding to the subcarrier, power adjustment is performed on the pilot information in the signal on the subcarrier in the carrier aggregation signal to restore the original pilot information corresponding to the pilot information; The adjusted carrier aggregation signal is demodulated.

5. The method according to claim 4, characterized in that The power adjustment factor corresponding to the subcarrier is calculated in the following way: The subcarrier number is multiplied by the power adjustment coefficient to obtain a power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the sequence numbers of the subcarriers are different positive integers.

6. A carrier aggregation device, characterized in that: Applied to a transmitter, the device comprises: An adjustment module, configured to perform power adjustment on the original pilot information in the signal on the subcarrier based on the power adjustment factor corresponding to the subcarrier to obtain an adjusted signal; An aggregation module, used for performing carrier aggregation on the adjusted signals on each subcarrier to obtain a carrier aggregation signal; A sending module is used to send the carrier aggregation signal to a receiver so that the receiver can adjust the power of the pilot information in the signal on each subcarrier in the carrier aggregation signal, restore the original pilot information corresponding to the pilot information, and demodulate the adjusted carrier aggregation signal.

7. The device according to claim 6, characterized in that The device also includes: The first calculation module is used to multiply the serial number of the subcarrier by the power adjustment coefficient to obtain the power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the serial number of each subcarrier is a different positive integer.

8. The device according to claim 6 or 7, characterized in that The device also includes: The filtering module is used to filter the adjusted signal.

9. A carrier aggregation device, characterized in that: Applied to a receiver, the device comprises: A receiving module, configured to receive a carrier aggregation signal sent by a transmitter, wherein the carrier aggregation signal is obtained by the transmitter performing carrier aggregation on the adjusted signals on each subcarrier, and the adjusted signal on the subcarrier is obtained by the transmitter performing power adjustment on the original pilot information in the signal on the subcarrier based on the power adjustment factor corresponding to the subcarrier; A restoration module, configured to perform power adjustment on the pilot information in the signal on the subcarrier in the carrier aggregation signal based on the power adjustment factor corresponding to the subcarrier, and restore the original pilot information corresponding to the pilot information; The demodulation module is used to demodulate the adjusted carrier aggregation signal.

10. The device according to claim 9, characterized in that The device also includes: The second calculation module is used to multiply the subcarrier number by the power adjustment coefficient to obtain the power adjustment factor corresponding to the subcarrier, wherein the power adjustment coefficient is calculated based on the total number of subcarriers, and the sequence numbers of each subcarrier are different positive integers.

11. A transmitter, characterized in that: It includes a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor is used to implement the method steps of any one of claims 1-3 when executing a program stored in a memory.

12. A receiver, characterized in that: It includes a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor is used to implement the method steps of any one of claims 4-5 when executing a program stored in a memory.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method steps of any one of claims 1-3 or 4-5 are implemented.

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