Data transmission method based on satellite base station and satellite base station

Abstract

The present invention provides a data transmission method and a satellite base station based on a satellite base station, which belong to the field of satellite communication technology. When the satellite base station currently uses a first frequency band to send data to a satellite, by waiting for the amount of data to be less than a first waiting amount threshold and the remaining power indicated by the remaining power information is less than the first power threshold, it is determined that there is less uplink data waiting to be sent to the satellite in the current base station and the remaining power of a power supply module of the satellite base station is less, then the first frequency band in use is automatically switched to a second frequency band with a lower frequency range, so that the frequency band in use matches the current data transmission situation and the remaining power situation, without manual operation and with timely response. Under the condition of satisfying the user experience, the power of the satellite base station is saved, the battery life of the satellite base station is extended, and the user experience is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of communication technology, and in particular to a satellite base station-based data transmission method and a satellite base station. Background Art

[0002] In the existing cellular communication system, the terminal is connected to the base station through a wireless interface, and the base station is connected to the core network through optical fiber. In some scenarios, such as natural disasters such as earthquakes and floods, or in desert environments, the communication link between the original base station and the core network is destroyed or there is no base station, forming a communication island. At this time, if you want to achieve communication between user equipment in a small range, you can use a satellite base station.

[0003] Satellite base stations are base stations that rely on high-throughput satellite platforms as transmission carriers to provide communication between terminals and satellites. Satellite base stations are connected to satellites through wireless interfaces, and satellites are then connected to core network elements on the ground, thereby realizing communication services for terminals.

[0004] In the application scenarios of satellite base stations, it is usually difficult for satellite base stations to obtain sufficient power supply and they need to rely on batteries. However, the battery life is not long, which affects the user experience. Summary of the invention

[0005] The present disclosure provides a data transmission method based on a satellite base station and a satellite base station, so as to solve the problem that the battery life of the satellite base station is short.

[0006] In a first aspect, the present disclosure provides a data transmission method based on a satellite base station, comprising:

[0007] Acquire data waiting information and remaining power information; the data waiting information includes the waiting data amount, and the waiting data amount is used to indicate the relevant information of the amount of uplink waiting data, and the uplink waiting data is the data stored in the cache of the satellite base station to be sent to the satellite;

[0008] In the case where the first frequency band is currently used to send data to the satellite, if the amount of waiting data is less than the first waiting amount threshold, and the remaining power indicated by the remaining power information is less than the first power threshold, a second frequency band is used to send data to the satellite, and the frequency range of the second frequency band is lower than the frequency range of the first frequency band.

[0009] In some embodiments, the method further comprises:

[0010] Periodically obtaining the amount of uplink waiting data;

[0011] The amount of waiting data is obtained by performing a weighted average on the quantities of all the uplink waiting data periodically acquired.

[0012] In some embodiments, the data waiting information further includes: a data waiting time, where the data waiting time is used to indicate the time taken by the satellite base station to receive data from the user equipment and send the data to the satellite; the method further includes:

[0013] When the first frequency band is currently used to send data to the satellite, if the amount of waiting data is greater than or equal to the first waiting amount threshold, the remaining power indicated by the remaining power information is less than the first power threshold, and the data waiting time is less than the first time threshold, the second frequency band is used to send data to the satellite.

[0014] In some embodiments, the method further comprises:

[0015] Acquire priority dimension information, where the priority dimension information is used to indicate that a frequency band used for sending data to the satellite is determined based on a remaining power or a data transmission rate of sending data to the satellite;

[0016] In the case where the first frequency band is currently used to send data to the satellite, if the amount of waiting data is greater than or equal to the first waiting amount threshold, the data waiting time is less than the first time threshold, the remaining power indicated by the remaining power information is greater than or equal to the first power threshold, and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the remaining power, then the second frequency band is used to send data to the satellite.

[0017] In some embodiments, the method further comprises:

[0018] Acquire priority dimension information, where the priority dimension information is used to indicate that a frequency band used for sending data to the satellite is determined based on a remaining power or a data transmission rate of sending data to the satellite;

[0019] In the case where the first frequency band is currently used to send data to the satellite, if the amount of waiting data is less than the first waiting amount threshold, the remaining power indicated by the remaining power information is greater than or equal to the first power threshold, and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the remaining power, then the second frequency band is used to send data to the satellite.

[0020] In some embodiments, the method further comprises:

[0021] When the second frequency band is currently used to send data to the satellite, if the waiting data amount is greater than a second waiting amount threshold and the remaining power indicated by the remaining power information is greater than the second power threshold, the first frequency band is used to send data to the satellite.

[0022] In some embodiments, the data waiting information further includes: a data waiting time, where the data waiting time is used to indicate the time taken by the satellite base station to receive data from the user equipment and send the data to the satellite; the method further includes:

[0023] When the second frequency band is currently used to send data to the satellite, if the amount of waiting data is less than or equal to the second waiting amount threshold, the data waiting time is greater than the second time threshold, and the remaining power information indicates that the remaining power of the satellite base station is greater than the second power threshold, the first frequency band is used to send data to the satellite.

[0024] In some embodiments, the method further comprises:

[0025] Acquire priority dimension information, where the priority dimension information is used to indicate that a frequency band used for sending data to the satellite is determined based on a remaining power or a data transmission rate of sending data to the satellite;

[0026] In the case where the second frequency band is currently used to send data to the satellite, if the amount of waiting data is less than or equal to the second waiting amount threshold, the data waiting time is greater than the second time threshold, the remaining power information indicates that the remaining power of the satellite base station is less than or equal to the second power threshold, and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the data transmission rate of the data sent to the satellite, then the first frequency band is used to send data to the satellite.

[0027] In some embodiments, the method further comprises:

[0028] Acquire priority dimension information, where the priority dimension information is used to indicate that a frequency band used for sending data to the satellite is determined based on a remaining power or a data transmission rate of sending data to the satellite;

[0029] In the case where the second frequency band is currently used to send data to the satellite, if the amount of waiting data is greater than the second waiting amount threshold, the remaining power information indicates that the remaining power of the satellite base station is less than or equal to the second power threshold, and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the data transmission rate of the data sent to the satellite, then the first frequency band is used to send data to the satellite.

[0030] In a second aspect, the present disclosure provides a satellite base station, comprising a memory and a processor, wherein the memory stores a computer program executable on the processor, and when the processor executes the program, the method described in the first aspect is implemented.

[0031] The embodiments of the present disclosure provide a data transmission method and a satellite base station based on a satellite base station. When the satellite base station is currently sending data to a satellite using the first frequency band, by waiting for the amount of data to be less than the first waiting amount threshold and the remaining power indicated by the remaining power information to be less than the first power threshold, it is determined that there is less uplink data waiting to be sent to the satellite in the current base station and the remaining power of the power supply module of the satellite base station is less. In this case, the first frequency band in use is automatically switched to a second frequency band with a lower frequency range, so that the frequency band in use matches the current data transmission situation and the remaining power situation. No manual operation is required and the response is timely. While satisfying the user experience, the satellite base station can save power, extend the battery life of the satellite base station, and improve the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic diagram of the structure of a communication system provided by an embodiment of the present disclosure;

[0033] Figure 2 A schematic diagram of the structure of a communication system based on a satellite base station provided in an embodiment of the present disclosure;

[0034] Figure 3 A schematic diagram of a data transmission method based on a satellite base station provided in an embodiment of the present disclosure;

[0035] Figure 4 A schematic diagram of a flow chart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure;

[0036] Figure 5 A schematic diagram of a flow chart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure;

[0037] Figure 6 A schematic diagram of a flow chart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure;

[0038] Figure 7 A schematic diagram of a flow chart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure;

[0039] Figure 8 A schematic diagram of a flow chart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure;

[0040] Fig. 9 A schematic diagram of a flow chart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure;

[0041] Fig.10 A flowchart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0042] Here, exemplary embodiments will be described in detail, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present disclosure.

[0043] In the present disclosure, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a alone, b alone, or c alone can mean: a alone, b alone, c alone, a and b in combination, a and c in combination, b and c in combination, or a, b, and c in combination, where a, b, and c can be single or multiple. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0044] The directions or positional relationships indicated by terms such as "center", "longitudinal", "lateral", "up", "down", "left", "right", "front", and "back" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present disclosure and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present disclosure.

[0045] The terms "connected" and "connected" should be understood in a broad sense. For example, the "connected" or "connected" of a circuit structure may refer to not only a physical connection, but also an electrical connection or a signal connection. For example, it may be a direct connection, i.e. a physical connection, or it may be an indirect connection through at least one intermediate element, as long as the circuit is connected. It may also be the internal connection of two elements. In addition to signal connection through a circuit, signal connection may also refer to signal connection through a media medium, such as radio waves. For those of ordinary skill in the art, the specific meanings of the above terms in this disclosure may be understood according to specific circumstances.

[0046] See also Figure 1 , Figure 1 A schematic diagram of the structure of a communication system provided in an embodiment of the present disclosure. The communication system provided in this embodiment includes but is not limited to: user equipment (UE), a base station, a core network and an external network, wherein: Figure 1The terminal device is exemplarily shown as UE, which is understandable that it does not constitute a limitation of the present disclosure. The terminal device is connected to the base station through a wireless interface, the base station is connected to the core network through an optical fiber, and the core network can be connected to the external network through an optical fiber. Among them, the terminal device includes but is not limited to a terminal device, a terminal, a UE, a mobile station, a mobile terminal, etc. The terminal device can specifically be a mobile phone, a tablet computer, a computer with wireless transceiver function, a wearable device, a vehicle, an airplane, a ship, a robot, a robotic arm, a smart home device, etc.

[0047] Compared with wireless interfaces, optical fiber interfaces have more reliable transmission and larger transmission capacity, so the optimization of communication systems mainly focuses on wireless interfaces.

[0048] However, once a natural disaster occurs, such as an earthquake or flood, the optical fiber interface is easily damaged, forming a temporary communication island. In this case, satellite base stations come into being.

[0049] See also Figure 2 , Figure 2 The structure diagram of a satellite base station-based communication system provided in an embodiment of the present disclosure includes, but is not limited to: UE, satellite base station, satellite, core network and external network. Figure 2 The terminal device is exemplarily shown as UE, but it can be understood that it does not constitute a limitation of the present disclosure. Figure 2 The communication system is compared with Figure 1 The difference lies in the connection method between the base station and the core network, that is, the satellite base station is connected to the satellite through a wireless interface, and the satellite is connected to the core network element on the ground to realize the communication service of the UE. The satellite base station can also be called a portable satellite base station or a mobile satellite base station. The satellite base station can be a backpack base station, a drone base station, a vehicle base station, etc.

[0050] In another scenario such as a desert, setting up Figure 1 The communication system shown is not economical and not necessary. If there are a small number of terminal devices in a small area for a short period of time and these terminal devices have communication needs, satellite base stations can be deployed. Figure 2 The communication system shown meets the communication needs.

[0051] In both scenarios mentioned above, satellite base stations can be deployed as follows: Figure 2 In the communication system shown in the figure, in these scenarios, it is usually difficult for the satellite base station to obtain sufficient power supply, and it needs to rely on the power supply module to supply power. The power supply module can be a battery, and the battery life is usually short. Therefore, in this scenario, the satellite base station needs to save power as much as possible to extend the battery life.

[0052] After analysis, the power consumption of satellite base stations mainly includes the following four aspects:

[0053] The satellite base station receives downlink data from the satellite;

[0054] The satellite base station sends downlink data to the terminal;

[0055] The satellite base station receives uplink data from the terminal;

[0056] The satellite base station sends uplink data to the satellite.

[0057] Among them, the power consumed by sending data accounts for the vast majority of the total power consumption. Sending data includes sending downlink data to the terminal and sending uplink data to the satellite. The power consumed by sending data can be obtained by the following formula (1):

[0058] The amount of power consumed to send data = the transmission power per unit frequency Transmitted frequency bandwidth formula (1)

[0059] The transmission power per unit frequency can also be called power spectrum density. For a satellite base station, the power spectrum density of downlink data sent to a terminal is basically constant, and the frequency bandwidth of downlink data depends on the amount of data sent; the power spectrum density of uplink data sent to a satellite depends on the frequency used by the satellite link, and the frequency bandwidth of uplink data sent to a satellite depends on the amount of uplink data.

[0060] The satellite base station and the satellite can use the first frequency band and the second frequency band for communication. The frequency ranges of the two frequency bands are different. The following takes the first frequency band as the Ka band and the second frequency band as the Ku band as an example for explanation. The frequency range of the Ku band is 12GHz-18GHz, and the frequency range of the Ka band is 20GHz-30GHz. The satellite base station can use the Ku band to transmit data with the satellite. The Ku band has a relatively low frequency, a longer wavelength, and a larger antenna size, but the signal attenuation is relatively small, so the power spectrum density required for signal transmission is lower. With the continuous development of antenna technology, satellite base stations can also use the Ka band to transmit data with satellites. The Ka band has a higher frequency, a shorter wavelength, a smaller antenna size, and a relatively large signal transmission attenuation, so a higher transmission power spectrum density is required per unit frequency band. On the other hand, the frequency domain available for the Ka band is wider than that of the Ku band, which can provide a higher data transmission rate.

[0061] Satellite base stations usually have two independent antennas installed, corresponding to the Ka band and Ku band respectively. Due to the limitation of baseband processing capability and power, usually only one of the antennas corresponding to these two bands is in working state, that is, the two do not work at the same time.

[0062] If the environment around the satellite base station changes, for example, the number of terminals accessing the satellite base station increases, or the transmission data rate of the terminals increases, or the remaining battery capacity of the satellite base station decreases, the operator of the satellite base station will need to manually select the Ka or Ku frequency band. If the response is not timely, it will affect the user experience.

[0063] Based on the above problems, the present disclosure provides a data transmission method based on a satellite base station. When the satellite base station is currently sending data to a satellite using a first frequency band, if there is less uplink data waiting to be sent to the satellite in the current satellite base station and the remaining power of a power supply module of the satellite base station is less, the first frequency band in use is automatically switched to a second frequency band with a lower frequency range. No manual operation is required and the response is timely. In addition, while satisfying the user experience, the power of the satellite base station is saved, the battery life of the satellite base station is extended, and the user experience is improved.

[0064] The implementation principle and beneficial effects of the technical solution of the present disclosure are described in detail below with specific embodiments.

[0065] See also Figure 3 , Figure 3 The present invention provides a flow chart of a satellite base station-based data transmission method according to an embodiment of the present invention. Figure 3 As shown, the method provided in this embodiment is executed by a satellite base station, and the satellite base station may be the satellite base station mentioned in the above embodiment. The method provided in this embodiment may include the following steps 301 to 305.

[0066] Step 301: Obtain data waiting information and remaining power information.

[0067] The data waiting information is used to indicate the relevant information of the data to be sent to the satellite in the buffer of the satellite base station. Hereinafter, the data to be sent to the satellite stored in the buffer of the satellite base station may also be referred to as uplink waiting data. The data waiting information may be the relevant information of the uplink waiting data within the most recent preset time period, or the relevant information of the uplink waiting data from the start of the satellite base station operation to the current moment.

[0068] The data waiting information may include but is not limited to the waiting data amount. The waiting data amount is used to indicate the relevant information of the amount of uplink waiting data. The uplink waiting data is the data in the buffer of the satellite base station to be sent to the satellite. The waiting data amount may also be called the average waiting data amount. The unit of the waiting data amount may be Byte, KByte, Mbyte, etc.

[0069] The remaining power information is used to indicate the remaining power of the power supply module of the satellite base station.

[0070] Exemplarily, the remaining power information may be the remaining power value, the remaining battery life, or the ratio of the remaining power to the nominal power.

[0071] Step 302: When the first frequency band is used to send data to the satellite, determine whether the waiting data amount is less than a first waiting amount threshold.

[0072] If yes, continue to execute step 303; if no, continue to execute step 304.

[0073] The first waiting amount threshold is a preset value. The first waiting amount threshold is used to indicate that the current uplink waiting data is small when the waiting data amount is less than the first waiting threshold. The first waiting amount threshold may be consistent with the unit of the waiting data amount. The first waiting amount threshold may be pre-stored in the satellite base station, or may be received through the human-machine interface of the satellite base station, or may be received from a network device, etc. The present disclosure does not limit the method for obtaining the first waiting amount threshold.

[0074] Step 303: determine whether the remaining power indicated by the remaining power information is less than a first power threshold.

[0075] If yes, continue to execute step 305; if no, continue to execute step 304.

[0076] The first power threshold is a preset value. The first power threshold is used to indicate that the current remaining power is small when the remaining power is less than the first waiting threshold. The first waiting threshold can be pre-stored in the satellite base station, or can be received through the human-machine interface of the satellite base station, or can be received from a network device, etc. The present disclosure does not limit the method for obtaining the first power threshold.

[0077] Exemplarily, if the remaining power information is the remaining power value, the unit of the first power threshold is consistent with the remaining power value. If the remaining power information is the ratio of the remaining power to the nominal power, the first power threshold can be a number greater than 0 and less than 1. For example, the first power threshold can be 50%. When the ratio of the remaining power to the nominal power is less than 50%, it is determined that the current remaining power is small. If the remaining power information is the remaining battery life, the first power threshold can be a preset duration. For example, the first power threshold can be 1 hour. When the remaining battery life is less than 1 hour, it is determined that the current remaining power is small.

[0078] Step 304: Send data to the satellite using the first frequency band.

[0079] Step 305: Use the second frequency band to send data to the satellite.

[0080] The frequency range of the second frequency band is lower than the frequency range of the first frequency band. Exemplarily, the first frequency band may be a Ka frequency band, and the second frequency band may be a Ku frequency band.

[0081] In this embodiment, the satellite base station obtains the waiting data amount and the remaining power information of the relevant information for indicating the amount of uplink waiting data inside the satellite base station. When the current satellite base station uses the first frequency band to send data to the satellite, if the waiting data amount is less than the first waiting amount threshold, and the remaining power indicated by the remaining power information is less than the first power threshold, it means that the amount of uplink data sent by the satellite base station at this time is small, and the current satellite base station has less remaining power. Then, a second frequency band with a lower frequency range than the first frequency band can be used to send data to the satellite, that is, the frequency band used to send data to the satellite is switched from the first frequency band to the second frequency band. Compared with using the first frequency band for uplink data transmission, the use of the second frequency band for uplink data transmission requires a lower power spectrum density, and accordingly, lower power consumption.

[0082] If the current amount of waiting data of the satellite base station is not less than the first waiting amount threshold, it means that the amount of uplink data sent by the satellite base station is large. If the second frequency band is used to send data to the satellite, it may affect the transmission rate, and the process of switching the frequency band may temporarily cause communication interruption. Therefore, the satellite base station continues to use the first frequency band to send data to the satellite.

[0083] If the remaining power indicated by the remaining power information of the current satellite base station is not less than the first power threshold, it means that the remaining power of the current satellite base station is large, and the process of switching the frequency band may temporarily cause communication interruption. Therefore, the satellite base station continues to use the first frequency band to send data to the satellite.

[0084] In this embodiment, when the satellite base station is currently sending data to the satellite using the first frequency band, by waiting for the amount of data to be less than the first waiting amount threshold and the remaining power indicated by the remaining power information is less than the first power threshold, it is determined that there is less uplink data waiting to be sent to the satellite in the current base station and the remaining power of the power supply module of the satellite base station is less. In this case, the first frequency band in use is automatically switched to a second frequency band with a lower frequency range, so that the frequency band in use matches the current data transmission situation and the remaining power situation. No manual operation is required and the response is timely. While satisfying the user experience, the satellite base station can save power, extend the battery life of the satellite base station, and improve the user experience.

[0085] In some embodiments, the waiting data amount may be a value that is continuously updated according to the current situation of the satellite base station. A method of obtaining the waiting data amount is exemplified below with reference to a specific embodiment.

[0086] In the above Figure 3On the basis of the illustrated embodiment, further, the method provided in this embodiment may also include the following steps 306 and 307 .

[0087] Step 306: Periodically obtain the amount of uplink waiting data.

[0088] The cycle time obtained above may be a preset duration, for example, 1 millisecond, 10 milliseconds, 100 milliseconds, 1 second, 10 seconds, etc.

[0089] The number of uplink waiting data may be the number of data packets of the uplink waiting data, that is, the number of uplink waiting data is the number of data packets stored in the cache of the satellite base station to be sent to the satellite.

[0090] Furthermore, periodically obtaining the number of uplink waiting data may be periodically obtaining the number of uplink waiting data after the satellite base station is powered on.

[0091] Step 307: Perform a weighted average on the quantities of all uplink waiting data periodically acquired to obtain the waiting data quantity.

[0092] In the above weighted average calculation, the earlier the amount of uplink waiting data is obtained, the lower the weight corresponding to it.

[0093] It should be noted that the shorter the set cycle time is, the more accurate the amount of waiting data obtained is; the longer the set cycle time is, the rougher the amount of waiting data obtained is.

[0094] The following takes a cycle of 10 milliseconds as an example. Every 10 milliseconds, the amount of data currently stored in the cache of the satellite base station to be sent to the satellite is detected, and a weighted average calculation is performed based on the amount of data obtained in all cycles to obtain the amount of waiting data.

[0095] Step 306 and step 307 in this embodiment can be performed simultaneously with the above steps 301 to 305. The waiting data amount obtained in step 301 is the waiting data amount obtained in step 307.

[0096] In this embodiment, the number of uplink waiting data is periodically obtained, and then a weighted average is performed according to the number of all uplink waiting data periodically obtained to obtain the waiting data amount. The waiting data amount is a variable quantity, which is updated in real time by the number of uplink waiting data periodically obtained. The waiting data amount can reflect the situation of data that needs to be sent inside the satellite base station but has not yet been sent to the satellite, that is, the situation of uplink waiting data currently stranded inside the satellite base station. It better reflects the situation of uplink data being sent inside the satellite base station, provides accurate and timely data support for frequency band switching, and then automatically switches frequency bands without manual operation and responds promptly, so that the power of the satellite base station is saved, the battery life of the satellite base station is extended, and the user experience is improved while satisfying the user experience.

[0097] Further, step 306 may be implemented by steps 3061 and 3062 as follows. Step 307 may be implemented by steps 3071 and 3072 as follows.

[0098] Step 3061: Obtain the current amount of uplink waiting data as the initial value of the waiting data amount.

[0099] Step 3062: At every periodic time, obtain the current amount of uplink waiting data as the current waiting amount.

[0100] Step 3071: Calculate the weighted average of the current waiting amount and the waiting data amount to obtain a corrected waiting data amount.

[0101] Step 3072: Update the waiting data amount to the corrected waiting data amount.

[0102] After returning to the preset execution time, the current amount of uplink waiting data is obtained as the current waiting amount.

[0103] In this embodiment, after the satellite base station is powered on, the current number of uplink waiting data is obtained as the initial value of the waiting data amount. The current number of uplink waiting data is obtained at periodic intervals as the current waiting amount. After the current waiting amount is obtained each time, the waiting data amount is corrected with the current waiting amount. For example, the weight of the current waiting amount can be set to 0.8, and the weight of the waiting data amount can be set to 0.2. The corrected waiting data amount is obtained according to the following formula (2):

[0104] Corrected waiting data amount = Formula (2)

[0105] Update the waiting data amount to the corrected waiting data amount, and continue to repeat the above process, that is, in the next cycle time, obtain the current amount of uplink waiting data as the current waiting amount, calculate the weighted average of the current waiting amount and the waiting data amount, obtain the corrected waiting data amount, and update the waiting data amount to the corrected waiting data amount.

[0106] Therefore, by periodically acquiring the current waiting amount, the waiting data amount is corrected. The waiting data amount is a gentle change process, and will not cause drastic changes in the waiting data amount due to data outliers. The waiting data amount can accurately reflect the situation of data that needs to be sent inside the satellite base station but has not yet been sent to the satellite, that is, the situation of uplink waiting data currently stranded inside the satellite base station. It better reflects the situation of uplink data sent inside the satellite base station, provides accurate and timely data support for frequency band switching, and then automatically switches the frequency band without manual operation and responds promptly, so that the power of the satellite base station is saved, the battery life of the satellite base station is extended, and the user experience is improved while satisfying the user experience.

[0107] In some scenarios, the data waiting information may also include a data waiting time, which is used to indicate the time taken by the satellite base station to receive data from the user equipment and send it to the satellite. In the process of determining whether to switch from the first frequency band to the second frequency band, a comprehensive determination may also be made based on the data waiting time, which is described in detail below with a specific embodiment.

[0108] See also Figure 4 , Figure 4 A flowchart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure. Figure 4 is in the above Figure 1 On the basis of the illustrated embodiment, further, when the judgment result of step 302 is no, the following step 401 is continued to be executed.

[0109] Step 401: Determine whether the data waiting time is less than a first time threshold.

[0110] If yes, continue to execute step 303; if no, continue to execute step 304.

[0111] The first duration threshold is a preset value. The first duration threshold is used to indicate that the current uplink waiting data is small when the waiting time is less than the first duration threshold. The first duration threshold may be consistent with the unit of the data waiting time. The first duration threshold may be pre-stored in the satellite base station, or may be received through the human-machine interface of the satellite base station, or may be received from a network device, etc. The present disclosure does not limit the method for obtaining the first duration threshold.

[0112] In this embodiment, the data waiting information may also include the data waiting time. The data waiting time is obtained in step 301. When the satellite base station currently uses the first frequency band to send data to the satellite, by waiting for the amount of data to be greater than or equal to the first waiting amount threshold, the data waiting time is less than the first time threshold, and the remaining power indicated by the remaining power information is less than the first power threshold, it is determined that there is less uplink data waiting to be sent to the satellite in the current satellite base station, and the remaining power of the power supply module of the satellite base station is less, then the first frequency band used is automatically switched to the second frequency band with a lower frequency range, without manual operation, and the response is timely. In addition, while satisfying the user experience, the satellite base station saves power, extends the battery life of the satellite base station, and improves the user experience.

[0113] In some embodiments, the data waiting time can be obtained by: for each data packet received by the satellite base station from the terminal device, a first data waiting time corresponds to the data waiting time, and all the first data waiting times are weighted averaged to obtain the data waiting time. The data waiting time can also be called the average data waiting time.

[0114] Among them, the first data waiting time can be obtained in the following way: the satellite base station receives an uplink data packet from the terminal, starts the timer, and when the uplink data packet is sent to the satellite, stops the timer. The value of the timer is the storage time length of the uplink data packet in the satellite base station, which is the first data waiting time.

[0115] Exemplarily, after the satellite base station is powered on, the initial value of the data waiting time is the first data waiting time of the first uplink data packet. For each uplink data packet, after obtaining its first data waiting time, the data waiting time is corrected by the first data waiting time. For example, the weight of the first data waiting time can be set to 0.8, and the weight of the data waiting time can be set to 0.2. The corrected data waiting time is obtained according to the following formula (3):

[0116] Corrected data waiting time = Formula (3)

[0117] Update the data waiting time to the corrected waiting data amount, and continue to repeat the above process, that is, after obtaining the first data waiting time of the next uplink data packet, calculate the weighted average of the first data waiting time and the data waiting time of the next uplink data packet, obtain the corrected data waiting time, and update the data waiting time to the corrected data waiting time.

[0118] In this embodiment, the data waiting time is corrected by continuously acquiring the latest first data waiting time. The data waiting time is a gentle change process, and will not cause drastic changes in the data waiting time due to data outliers. The data waiting time can accurately reflect the situation of data that needs to be sent inside the satellite base station but has not yet been sent to the satellite, that is, the situation of uplink waiting data currently stranded inside the satellite base station. It better reflects the situation of uplink data being sent inside the satellite base station, provides accurate and timely data support for frequency band switching, and then automatically switches the frequency band without manual operation and responds promptly, so that the power of the satellite base station is saved, the battery life of the satellite base station is extended, and the user experience is improved while satisfying the user experience.

[0119] In some scenarios, priority dimension information can also be obtained, and the priority dimension information is used to indicate whether to prioritize the remaining power or the data transmission rate of sending data to the satellite to determine the frequency band used to send data to the satellite. Among them, prioritizing the remaining power to determine the frequency band used to send data to the satellite means giving priority to frequency bands with lower power consumption; prioritizing the data transmission rate to determine the frequency band used to send data to the satellite means giving priority to frequency bands with higher data transmission rates. In the process of determining whether to switch from the first frequency band to the second frequency band, a comprehensive judgment can also be made based on the priority dimension information, which is described in detail below with specific embodiments.

[0120] See also Figure 5 , Figure 5 A flowchart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure. Figure 5 is in the above Figure 1 On the basis of the illustrated embodiment, further, when the judgment result of step 303 is no, the following step 501 is continued to be executed.

[0121] Step 501: Determine whether the priority dimension information indicates that the frequency band used for sending data to the satellite is determined based on the remaining power.

[0122] If yes, continue to execute step 305; if no, continue to execute step 304.

[0123] Among them, the priority dimension information can be pre-stored in the satellite base station, or received through the human-machine interface of the satellite base station, or received from a network device, etc. The present disclosure does not limit the method for obtaining the priority dimension information.

[0124] In this embodiment, priority dimension information is also obtained for judging the frequency band switching. When the satellite base station is currently sending data to the satellite using the first frequency band, by waiting for the amount of data to be less than the first waiting amount threshold, the remaining power indicated by the remaining power information is less than the first power threshold, and the priority dimension information indicates that the frequency band used to send data to the satellite is determined based on the remaining power, it can be determined that there is less uplink data waiting to be sent to the satellite in the current satellite base station, and the satellite base station currently prioritizes the remaining power to determine the frequency band used to send data to the satellite. The first frequency band used is automatically switched to a second frequency band with a lower frequency range, without manual operation, and with timely response. In addition, while satisfying the user experience, the satellite base station can save power, extend the battery life of the satellite base station, and improve the user experience.

[0125] In some scenarios, based on the above discussion, the data waiting information may also include the data waiting time, and the priority selection dimension information may also be obtained. In the process of judging whether to switch from the first frequency band to the second frequency band, a comprehensive judgment may be made based on the data waiting time and the priority selection dimension information. This is described in detail with specific embodiments below.

[0126] See also Figure 6 , Figure 6 A flowchart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure. Figure 6 is in the above Figure 1 On the basis of the embodiment shown, further, when the judgment result of step 302 is no, the following step 601 is continued to be executed. When the judgment result of step 303 is no, the following step 602 is continued to be executed.

[0127] Step 601: Determine whether the data waiting time is less than a first time threshold.

[0128] If yes, continue to execute step 303; if no, continue to execute step 304.

[0129] Step 602: Determine whether the priority selection dimension information indicates that the frequency band used for sending data to the satellite is determined based on the remaining power.

[0130] If yes, continue to execute step 305; if no, continue to execute step 304.

[0131] In this embodiment, step 601 is similar to the above step 401, and step 602 is similar to the above step 501, which will not be repeated here.

[0132] In this embodiment, when the satellite base station is currently sending data to the satellite using the first frequency band, it determines that there is less uplink data waiting to be sent to the satellite in the current satellite base station by waiting for the amount of data to be less than the first waiting amount threshold, or the amount of data to be waited is greater than or equal to the first waiting amount threshold and the data waiting time is less than the first time threshold, and then further determines that the remaining power indicated by the remaining power information is less than the first power threshold, or the remaining power indicated by the remaining power information is greater than or equal to the first power threshold and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the remaining power, and it is determined that the remaining power in the current satellite base station is prioritized. The first frequency band in use is automatically switched to a second frequency band with a lower frequency range, without the need for manual operation and with timely response. While satisfying the user experience, it saves power of the satellite base station, extends the battery life of the satellite base station, and improves the user experience.

[0133] In some scenarios, when the satellite base station currently uses the second frequency band to send data to the satellite, it can be determined whether the second frequency band needs to be switched to the first frequency band based on the amount of waiting data and the remaining power information, thereby improving the data transmission efficiency. The following is a detailed description with specific embodiments.

[0134] See also Figure 7 , Figure 7 A flowchart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure. Figure 7 The method can be implemented alone or in combination with the above Figure 1 The embodiments shown are implemented in combination. The method provided in this embodiment may include the following steps 701-step.

[0135] Step 701: When currently sending data to a satellite using a second frequency band, determine whether the amount of waiting data is greater than a second waiting amount threshold.

[0136] If yes, continue to execute step 702; if no, continue to execute step 703.

[0137] Among them, the second waiting amount threshold is a preset value. The second waiting amount threshold is used to indicate that the current uplink waiting data is small when the waiting data amount is less than the second waiting amount threshold. The second waiting amount threshold can be consistent with the unit of the waiting data amount. The second waiting amount threshold can be pre-stored in the satellite base station, or it can be received through the human-machine interface of the satellite base station, or it can be received from a network device, etc. The present disclosure does not limit the method for obtaining the first waiting amount threshold. The second waiting amount threshold is greater than the first waiting amount threshold. Since the satellite base station may cause temporary interruption of communication during the process of changing the frequency band, different first waiting amount thresholds and second waiting amount thresholds are set correspondingly for the waiting data amount to achieve a hysteresis effect, thereby achieving the goal of not easily changing the frequency band.

[0138] Step 702: Determine whether the remaining power indicated by the remaining power information is greater than a second power threshold.

[0139] If yes, continue to execute step 704; if no, continue to execute step 703.

[0140] The second power threshold is a preset value. The second power threshold is used to indicate that the current remaining power is large when the remaining power is greater than the second waiting threshold. The second power threshold can be pre-stored in the satellite base station, or can be received through the human-machine interface of the satellite base station, or can be received from a network device, etc. The present disclosure does not limit the method for obtaining the second power threshold. The second power threshold can be the same as the first power threshold, or can be greater than the first power threshold.

[0141] Step 703: Send data to the satellite using the second frequency band.

[0142] Step 704: Send data to the satellite using the first frequency band.

[0143] The frequency range of the second frequency band is lower than the frequency range of the first frequency band. Exemplarily, the first frequency band may be a Ka frequency band, and the second frequency band may be a Ku frequency band.

[0144] In this embodiment, when the satellite base station is currently sending data to the satellite using the second frequency band, if the amount of waiting data is greater than the second waiting amount threshold, and the remaining power indicated by the remaining power information is greater than the second power threshold, it means that the amount of uplink data sent by the satellite base station is large, and the current remaining power of the satellite base station is large, then the first frequency band with a higher frequency range than the second frequency band can be used to send data to the satellite, that is, the frequency band used to send data to the satellite is switched from the second frequency band to the first frequency band. Compared with using the second frequency band for uplink data transmission, using the first frequency band for uplink data transmission can send uplink data at a higher data transmission rate.

[0145] If the current amount of waiting data of the satellite base station is not greater than the second waiting amount threshold, it means that the amount of uplink data sent by the satellite base station is not large. If the first frequency band is used to send data to the satellite, it may cause waste and increase power consumption, and the process of switching frequency bands may temporarily cause communication interruption. Therefore, the satellite base station continues to use the second frequency band to send data to the satellite.

[0146] If the remaining power indicated by the remaining power information of the current satellite base station is not greater than the second power threshold, it means that the remaining power of the current satellite base station is not much, and the process of switching the frequency band may temporarily cause communication interruption. Therefore, the satellite base station continues to use the second frequency band to send data to the satellite.

[0147] In this embodiment, when the satellite base station is currently sending data to the satellite using the second frequency band, by waiting for the amount of data to be greater than the second waiting amount threshold and the remaining power indicated by the remaining power information being greater than the second power threshold, it is determined that the amount of uplink data currently sent by the satellite base station is large and the remaining power of the power supply module of the current satellite base station is large, then the second frequency band in use is automatically switched to the first frequency band with a higher frequency range, so that the frequency band in use matches the current data transmission situation and the remaining power situation, without the need for manual operation and with a timely response, and when the satellite base station has sufficient power, the data transmission rate of the data sent by the satellite base station to the satellite is increased, thereby improving the user experience.

[0148] In some scenarios, the data waiting information may also include a data waiting time, which is used to indicate the time taken by the satellite base station to receive data from the user equipment and send it to the satellite. The data waiting time is the same as the data waiting time in the above embodiment, and will not be described in detail here. In the process of determining whether to switch from the second frequency band to the first frequency band, a comprehensive judgment may also be made based on the data waiting time, which is described in detail below with a specific embodiment.

[0149] See also Figure 8 , Figure 8 A flowchart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure. Figure 8 is in the above Figure 7 On the basis of the illustrated embodiment, further, when the judgment result of step 701 is no, continue to execute the following step 801.

[0150] Step 801: Determine whether the data waiting time is greater than a second time threshold.

[0151] If yes, continue to execute step 702; if no, continue to execute step 703.

[0152] The second duration threshold is greater than the first duration threshold. Since the satellite base station may cause temporary communication interruption during the process of changing the frequency band, different first duration thresholds and second duration thresholds are set for the data waiting time to achieve a hysteresis effect, so as not to easily change the frequency band.

[0153] In this embodiment, the data waiting information may also include the data waiting time. When the satellite base station is currently sending data to the satellite using the second frequency band, by waiting for the data amount not greater than the second waiting amount threshold, the waiting time greater than the second time threshold, and the remaining power indicated by the remaining power information greater than the second power threshold, it is determined that the current satellite base station sends a large amount of uplink data, and the current satellite base station has a large amount of remaining power in the power supply module, the second frequency band used is automatically switched to the first frequency band with a higher frequency range, so that the used frequency band matches the current data transmission situation and the remaining power situation, without manual operation, and the response is timely. When the satellite base station has sufficient power, the data transmission rate of the satellite base station sending data to the satellite is increased, thereby improving the user experience.

[0154] In some scenarios, priority dimension information can also be obtained, and the priority dimension information is used to indicate that the frequency band used to send data to the satellite is determined based on the remaining power or the data transmission rate of the data sent to the satellite. The priority dimension information is the same as the priority dimension information in the above embodiment and is not repeated here. In the process of determining whether to switch from the second frequency band to the first frequency band, a comprehensive judgment can also be made based on the priority dimension information, which is described in detail below with specific embodiments.

[0155] See also Fig. 9 , Fig. 9 A flowchart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure. Fig. 9 is in the above Figure 7 On the basis of the illustrated embodiment, further, when the judgment result of step 702 is no, continue to execute the following step 901.

[0156] Step 901: Whether the dimension information is preferentially selected to indicate that a frequency band used for sending data to a satellite is preferentially determined based on a data transmission rate of the data sent to the satellite.

[0157] If yes, continue to execute step 704; if no, continue to execute step 703.

[0158] In this embodiment, priority dimension information is also obtained for judging the frequency band switching. When the satellite base station currently uses the second frequency band to send data to the satellite, by waiting for the amount of data to be greater than the second waiting amount threshold, the remaining power indicated by the remaining power information is not greater than the second power threshold, and whether the priority dimension information indicates that the frequency band used to send data to the satellite is determined based on the data transmission rate of the data sent to the satellite, it is determined that the current amount of uplink data sent by the satellite base station is large, and the frequency band used to send data to the satellite is determined based on the data transmission rate of the data sent to the satellite, then the second frequency band used is automatically switched to the first frequency band with a higher frequency range, so that the used frequency band matches the current data transmission situation and the remaining power situation, without manual operation, and the response is timely. When the power of the satellite base station is sufficient, the data transmission rate of the satellite base station sending data to the satellite is increased, thereby improving the user experience.

[0159] In some scenarios, based on the above discussion, the data waiting information may also include the data waiting time, and the priority selection dimension information may also be obtained. In the process of judging whether to switch from the second frequency band to the first frequency band, a comprehensive judgment may be made based on the data waiting time and the priority selection dimension information. This is explained in detail with specific embodiments below.

[0160] See also Fig.10 , Fig.10 A flowchart of another satellite base station-based data transmission method provided in an embodiment of the present disclosure. Fig.10 is in the above Figure 7 On the basis of the embodiment shown, further, when the judgment result of step 701 is no, the following step 1001 is continued to be executed. When the judgment result of step 702 is no, the following step 1002 is continued to be executed.

[0161] Step 1001: Determine whether the data waiting time is greater than a second time threshold.

[0162] If yes, continue to execute step 702; if no, continue to execute step 703.

[0163] Step 1002: Whether the dimension information indicates that the frequency band used for sending data to the satellite is determined based on the data transmission rate of the data sent to the satellite.

[0164] If yes, continue to execute step 704; if no, continue to execute step 703.

[0165] In this embodiment, step 1001 is similar to the above step 801, and step 1002 is similar to the above step 901, which will not be repeated here.

[0166] In this embodiment, when the satellite base station is currently using the second frequency band to send data to the satellite, it determines that there is a lot of uplink data waiting to be sent to the satellite in the current satellite base station by waiting for the amount of data to be greater than the second waiting amount threshold, or the amount of data to be waited is not greater than the second waiting amount threshold and the data waiting time is greater than the second time threshold, and then further determines that the remaining power indicated by the remaining power information is greater than the first power threshold, or the remaining power indicated by the remaining power information is not greater than the second power threshold and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the data transmission rate of the data sent to the satellite, and it is determined that the current satellite base station sends uplink data to prioritize the data transmission rate, and then automatically switches the used second frequency band to the first frequency band with a higher frequency range, so that the used frequency band matches the current data transmission situation and the remaining power situation, without manual operation, and the response is timely. When the satellite base station has sufficient power, the data transmission rate of the satellite base station sending data to the satellite is increased, thereby improving the user experience.

[0167] An embodiment of the present disclosure provides a satellite base station, including a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the program, the method in any of the above embodiments is implemented.

[0168] Based on the satellite base station-based data transmission method described in any of the above embodiments, the embodiment of the present disclosure further provides a computer-readable storage medium, for example, the non-temporary computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, and an optical data storage device, etc. The storage medium stores computer instructions for executing the satellite base station-based data transmission method described in any of the above embodiments, which will not be described in detail herein.

[0169] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware, or by a program to instruct the relevant hardware, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0170] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The description and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims.

Claims

1. A data transmission method based on a satellite base station, characterized in that: The method comprises: Acquire data waiting information and remaining power information; the data waiting information includes the waiting data amount, and the waiting data amount is used to indicate the relevant information of the amount of uplink waiting data, and the uplink waiting data is the data stored in the cache of the satellite base station to be sent to the satellite; In the case where the first frequency band is currently used to send data to the satellite, if the waiting data amount is less than a first waiting amount threshold, and the remaining power indicated by the remaining power information is less than the first power threshold, a second frequency band is used to send data to the satellite, and the frequency range of the second frequency band is lower than the frequency range of the first frequency band; The data waiting information further includes: a data waiting time, wherein the data waiting time is used to indicate the time taken by the satellite base station to receive data from the user equipment and send the data to the satellite; the method further includes: In the case where the first frequency band is currently used to send data to the satellite, if the waiting data amount is greater than or equal to the first waiting amount threshold, the remaining power indicated by the remaining power information is less than the first power threshold, and the data waiting time is less than the first time threshold, then the second frequency band is used to send data to the satellite; The method further comprises: Acquire priority dimension information, where the priority dimension information is used to indicate that a frequency band used for sending data to the satellite is determined based on a remaining power or a data transmission rate of sending data to the satellite; In the case where the first frequency band is currently used to send data to the satellite, if the amount of waiting data is greater than or equal to the first waiting amount threshold, the data waiting time is less than the first time threshold, the remaining power indicated by the remaining power information is greater than or equal to the first power threshold, and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the remaining power, then the second frequency band is used to send data to the satellite.

2. The method according to claim 1, characterized in that The method further comprises: Periodically obtaining the amount of uplink waiting data; The amount of waiting data is obtained by performing a weighted average on the quantities of all the uplink waiting data periodically acquired.

3. The method according to claim 1 or 2, characterized in that: The method further comprises: Acquire priority dimension information, where the priority dimension information is used to indicate that a frequency band used for sending data to the satellite is determined based on a remaining power or a data transmission rate of sending data to the satellite; In the case where the first frequency band is currently used to send data to the satellite, if the amount of waiting data is less than the first waiting amount threshold, the remaining power indicated by the remaining power information is greater than or equal to the first power threshold, and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the remaining power, then the second frequency band is used to send data to the satellite.

4. The method according to claim 1 or 2, characterized in that: The method further comprises: When the second frequency band is currently used to send data to the satellite, if the waiting data amount is greater than a second waiting amount threshold and the remaining power indicated by the remaining power information is greater than the second power threshold, the first frequency band is used to send data to the satellite.

5. The method according to claim 4, characterized in that The data waiting information further includes: a data waiting time, wherein the data waiting time is used to indicate the time taken by the satellite base station to receive data from the user equipment and send the data to the satellite; the method further includes: When the second frequency band is currently used to send data to the satellite, if the amount of waiting data is less than or equal to the second waiting amount threshold, the data waiting time is greater than the second time threshold, and the remaining power information indicates that the remaining power of the satellite base station is greater than the second power threshold, the first frequency band is used to send data to the satellite.

6. The method according to claim 4, characterized in that The method further comprises: Acquire priority dimension information, where the priority dimension information is used to indicate that a frequency band used for sending data to the satellite is determined based on a remaining power or a data transmission rate of sending data to the satellite; In the case where the second frequency band is currently used to send data to the satellite, if the amount of waiting data is less than or equal to the second waiting amount threshold, the data waiting time is greater than the second time threshold, the remaining power information indicates that the remaining power of the satellite base station is less than or equal to the second power threshold, and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the data transmission rate of the data sent to the satellite, then the first frequency band is used to send data to the satellite.

7. The method according to claim 4, characterized in that The method further comprises: Acquire priority dimension information, where the priority dimension information is used to indicate that a frequency band used for sending data to the satellite is determined based on a remaining power or a data transmission rate of sending data to the satellite; In the case where the second frequency band is currently used to send data to the satellite, if the amount of waiting data is greater than the second waiting amount threshold, the remaining power information indicates that the remaining power of the satellite base station is less than or equal to the second power threshold, and the priority selection dimension information indicates that the frequency band used to send data to the satellite is determined based on the data transmission rate of the data sent to the satellite, then the first frequency band is used to send data to the satellite.

8. A satellite base station, comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, characterized in that: When the processor executes the program, the method according to any one of claims 1 to 7 is implemented.

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