JP6514131B2 - Base station controller, base station control method and base station control system - Google Patents

Description

  The present invention relates to a base station control apparatus, a base station control method, and a base station control system that control conditions for transmitting radio waves by a base station for wireless communication.

  It is known that radio waves in high frequency bands are attenuated by rainfall. Patent Document 1 discloses a technique for controlling the intensity of a radio wave transmitted by a satellite based on the amount by which the radio wave is attenuated due to the influence of rainfall.

JP, 2015-76710, A

  By increasing the intensity of the radio wave transmitted by the satellite at the time of rainfall using the conventional technique, it is possible to improve the reception quality at the earth station that receives the radio wave from the satellite. However, it has been difficult to improve the quality of communication between the satellite and the earth station if the strength of the radio wave transmitted by the satellite or the earth station can not be increased.

  Therefore, the present invention has been made in view of these points, and it is possible to improve the communication quality between the satellite and the earth station without changing the strength of the radio wave transmitted by the earth station. An apparatus, a base station control method, and a base station control system are provided.

  According to a first aspect of the present invention, there is provided a first estimation unit for estimating a first attenuation amount in an earth station in radio communication with a satellite, and a second estimation unit in a predetermined range from a base station in radio communication with a plurality of mobile terminals. A second estimation unit that estimates an attenuation amount; a carrier level calculation unit that calculates a carrier level of the satellite in a wireless communication channel between the satellite and the earth station based on the first attenuation amount; An interference amount calculation unit that calculates an interference amount given to the satellite by at least one of the base station and the one or more mobile terminals with which the base station communicates based on two attenuation amounts; the carrier level and the interference And a control unit configured to control a condition for transmitting radio waves from the base station to the one or more mobile terminals based on a relationship with a quantity.

  The control unit controls the power or direction of radio waves transmitted from the base station to the plurality of mobile terminals based on, for example, the relationship between the carrier wave level and the amount of interference.

  Further, the control unit causes the base station to transmit to the plurality of mobile terminals when the sum of the interference amount and the estimated amount of noise in the satellite is equal to or more than a predetermined threshold with respect to the carrier level. The conditions for transmitting radio waves may be changed.

  Further, the control unit is configured to transmit the radio wave transmitted from the base station to the plurality of mobile terminals when a sum of the interference amount and the estimation amount is equal to or more than a predetermined threshold value with respect to the carrier level. Power may be reduced.

  The interference amount calculation unit calculates the interference amount based on, for example, the number of mobile terminals managed in the cell of the base station or the number of the one or more mobile terminals transmitting radio waves. The interference amount calculation unit is an overlapping frequency band in which a second frequency band used for wireless communication by the base station overlaps the first frequency band with respect to a size of a first frequency band used for wireless communication by the satellite. The amount of interference may be calculated based on the ratio of the magnitude of.

  The first estimation unit estimates the first attenuation amount based on, for example, the rainfall amount at the earth station or interference information input in advance, and the second estimation unit estimates the rainfall amount at the base station or The second attenuation amount is estimated based on the input interference information.

  The interference amount calculation unit is configured to transmit the plurality of base stations provided in a range where radio waves can reach the satellite, and the plurality of mobile terminals with which the plurality of base stations communicate. Calculating the amount of interference to be applied to the plurality of mobile terminals from at least one of the plurality of base stations based on the amount of interference calculated by the interference amount calculation unit. The conditions for transmitting radio waves may be controlled.

  The control unit changes, among the plurality of base stations, the condition for transmitting radio waves to the plurality of mobile terminals from the base station whose interference amount calculated by the interference amount calculating unit is equal to or greater than a predetermined threshold. You may

  In a second aspect of the present invention, there is provided the steps of: estimating a first attenuation amount in an earth station in radio communication with a satellite; and estimating a second attenuation amount in a base station in radio communication with a plurality of mobile terminals. Calculating the carrier level of the satellite of the wireless communication channel between the satellite and the earth station based on the first attenuation amount; and the base station and the base based on the second attenuation amount. Calculating the amount of interference given to the satellite by at least one of the one or more mobile terminals with which the station communicates, and based on the relationship between the carrier wave level and the amount of interference, the one or more from the base station And B. controlling the conditions for transmitting radio waves to the mobile terminal.

  In a third aspect of the present invention, there is provided a base station comprising: a base station in radio communication with a plurality of mobile terminals; and a base station control device for controlling the power of radio waves transmitted by the base station to the plurality of mobile terminals. In the station control system, the base station control device comprises a first estimation unit for estimating a first attenuation amount in an earth station in radio communication with a satellite, and a second in a base station in radio communication with a plurality of mobile terminals. A second estimation unit that estimates an attenuation amount; a carrier level calculation unit that calculates a carrier level of the satellite in a wireless communication channel between the satellite and the earth station based on the first attenuation amount; An interference amount calculation unit that calculates an interference amount given to the satellite by at least one of the base station and the one or more mobile terminals with which the base station communicates based on two attenuation amounts; the carrier level and the interference The relation with quantity And a control unit that controls conditions for transmitting radio waves from the base station to the one or more mobile terminals based on the base station, the base station determines the conditions based on the conditions determined by the control unit. A base station control system for transmitting radio waves to the plurality of mobile terminals is provided.

  According to the present invention, the communication quality between the satellite and the earth station can be improved without changing the strength of the radio wave transmitted by the earth station.

It is a figure for demonstrating the outline | summary of the base station control system which concerns on this embodiment. It is a figure for demonstrating the condition which an interference wave generate | occur | produces. It is a figure which shows the structure of a base station control system. It is a figure which shows the operation | movement sequence of a base station control system. It is an operation | movement flowchart of the base station control server which concerns on this embodiment.

[Overview of Base Station Control System S]
FIG. 1 is a diagram for explaining an outline of a base station control system S according to the present embodiment. In FIG. 1, the relationships among the satellites ST (STa, STb, STc), the earth station ES, the base station BS, and the mobile terminal MS are shown. Hereinafter, when it is not necessary to distinguish the satellites STa, STb, and STc, they may be collectively referred to as satellites ST.

  The satellite ST transmits and receives data using radio waves with the earth station ES installed on the ground. In FIG. 1, radio wave transmission ranges from the ground that can be received by the satellites STa, STb, and STc are shown as satellite footprints Pa, Pb, and Pc. The satellite STa can receive data from the earth station ES in the satellite footprint Pa.

  The base station BS is a base station of a mobile phone network. The base station BS transmits and receives data by transmitting and receiving radio waves to and from a plurality of mobile terminals MS in the cell via a wireless communication channel. Part of the frequency band used in wireless communication between the base station BS and the mobile terminal MS overlaps with the frequency band used by the satellite ST for wireless communication with the earth station ES. Therefore, radio waves transmitted by the base station BS and the mobile terminal MS become interference waves in the wireless communication between the satellite ST and the earth station ES.

  The influence of radio waves transmitted by the base station BS and the mobile terminal MS on radio communication between the satellite ST and the earth station ES depends on the weather. In particular, if the frequency band used in wireless communication between the base station BS and the mobile terminal MS and wireless communication between the satellite ST and the earth station ES is a band of several tens of GHz or more, the influence of rainfall Radio waves are attenuated in areas where there is rainfall.

  Therefore, for example, when there is rainfall near the earth station ES, the radio wave received by the satellite ST from the earth station ES (hereinafter referred to as a carrier wave) is attenuated. In this state, if the radio wave (hereinafter referred to as interference wave) transmitted from the base station BS installed in the area where there is no rainfall reaches the satellite ST without being attenuated by the influence of the rainfall, the satellite ST will be earth station As the ratio of the interference wave to the carrier wave received from the ES increases, the data error rate increases.

  In the base station control system S according to the present embodiment, a base for controlling the conditions under which the base station BS transmits radio waves in order to suppress the influence of interference waves on radio communication between the satellite ST and the earth station ES. A station control server 1 is provided. The base station control server 1 acquires rainfall data from an external database, estimates the amount of rainfall attenuation around the base station BS and the earth station ES, and based on the estimation result, transmits the radio waves transmitted by the base station BS The base station controller controls the power of the base station BS and controls the tilt angle in the direction in which the base station BS transmits radio waves. By the base station control server 1 controlling the base station BS in this manner, the wireless communication line between the satellite ST and the earth station ES is a wireless communication line and frequency band between the base station BS and the mobile terminal MS. Even when a part of the above is shared, the influence of the radio waves transmitted by the base station BS and the mobile terminal MS on the wireless communication between the satellite ST and the earth station ES can be suppressed.

FIG. 2 is a diagram for explaining a situation in which an interference wave is generated. In the satellite footprint Pa in FIG. 2, three base stations _{BS n, BS n + 1,} BS n + 2 of the cell area _{CA n, CA n + 1,} CA n + 2 are shown. From CA _n , the interference wave IW _n reaches the satellite STa, from CA _{n + 1} the interference wave IW _{n + 1} reaches the satellite STa, and from CA _{n + 2} the interference wave IW _{n + 2} is the satellite STa Will arrive at From ES _m , the carrier CW _m reaches the satellite STa. The base station control server 1 is a base installed in the satellite footprint Pa based on the relationship between the sum I of interference waves emitted from all cell areas in the satellite footprint Pa of the satellite STa and the carrier wave CW _m . Control the transmission power of the station BS.

[Configuration of base station control system S]
FIG. 3 is a diagram showing the configuration of the base station control system S. As shown in FIG. The base station control system S has a base station control server 1 and a base station BS. The base station control server 1 has a storage unit 11 and a CPU (Central Processing Unit) 12.

  The storage unit 11 is a storage medium such as, for example, a read only memory (ROM), a random access memory (RAM), or a hard disk. The storage unit 11 stores various programs such as a program executed by the CPU 12, an estimated value of rainfall attenuation generated by the CPU 12, a carrier wave level C, and an interference amount I.

  The CPU 12 functions as a first estimation unit 121, a second estimation unit 122, a carrier wave level calculation unit 123, an interference amount calculation unit 124, and a control unit 125 by executing a program stored in the storage unit 11. The base station BS has a terminal control unit 21 and a wireless power control unit 22.

  The first estimation unit 121 estimates the first rainfall attenuation amount in the earth station ES that communicates wirelessly with the satellite ST. The first estimation unit 121, for example, notifies the rainfall database DB of location information of the earth station ES, and from the rainfall database DB, rainfall indicating the rainfall condition around the location of the earth station ES corresponding to the notified location information. Get data The first estimation unit 121 estimates, based on the acquired rainfall data, a first rainfall attenuation amount indicating an attenuation amount of a radio wave propagated from the earth station ES toward the satellite ST. The first estimation unit 121 stores the estimated first rainfall attenuation amount in the storage unit 11.

  The second estimation unit 122 estimates a second rainfall attenuation amount in a predetermined range from the base station BS that performs wireless communication with a plurality of mobile terminals MS. Similar to the first estimation unit 121, the second estimation unit 122 notifies location information of the base station BS to the rainfall database DB, and the location information of the base station BS corresponding to the notified location information from the rainfall database DB. Acquire rainfall data that shows the rainfall situation in the surrounding area. The second estimation unit 122 estimates a second rainfall attenuation amount indicating the attenuation amount of the radio wave propagated from the base station BS toward the satellite ST based on the acquired rainfall data. The second estimation unit 122 stores the estimated second rainfall attenuation amount in the storage unit 11.

The carrier level calculation unit 123 calculates the carrier level C in the satellite ST of the wireless communication channel between the satellite ST and the earth station ES based on the first rainfall attenuation amount estimated by the first estimation unit 121. Carrier level C is effective radiated power EIRP _ES earth station, the propagation loss L _C (free-space propagation loss L _{F_C,} atmospheric attenuation L _{Atom_C,} rain attenuation L _{Rain_C} etc.), and based on the received antenna gain G _{R_c,} the following It is obtained by the formula.
_{C = EIRP ES - L f_C -} L atom_C - L rain_C + G r_C (dBm)

  The interference amount calculation unit 124 gives the satellite ST at least one of the base station BS and one or more mobile terminals MS with which the base station BS communicates based on the second rainfall attenuation amount estimated by the second estimation unit 122. The amount of interference I is calculated. The interference amount calculation unit 124 preferably calculates the sum of the interference amounts given to the satellite ST by all of the base station BS and the plurality of MSs, but the interference amount given to the satellite ST by only the base station BS or movement of one or more The amount of interference given to the satellite ST by the terminal MS may be calculated.

n-th (n is an integer) the interference level i _n from the cell of the base station BS _n, the effective radiated power EIRP _IMT from the cell of the base station BS _n to the satellite direction, the propagation loss L _I (free-space propagation loss L _{Based on f_I} , atmospheric attenuation _{Latom_I} , rainfall attenuation _{Lrain_I,} etc., and the receiving antenna gain _{Gr_I,} it is obtained by the following equation. However, EIRP _IMT is the number of active terminals acquired from the terminal control unit 21 and is a value indicating the number of mobile terminals MS that transmit radio waves in the cell of the base station BS _n .
i _n = EIRP _IMT- L _{f I} -L _{atom I} -L _{rain I} + G _{r I} (dBm)

Here, the interference amount calculation unit 124 uses the effective radiation power EIRP _IMT obtained by correcting the sum of the effective radiation power in the cell of the base station BS _n in the direction of the satellite ST based on the band competition rate. The amount of interference i _n is calculated. The band competition rate is the ratio of the overlapping frequency band in which the satellite frequency band and the base station frequency band used by the base station BS overlap to the satellite frequency band used by the satellite ST. For example, when the satellite frequency band is from 28,000 MHz to 28,500 MHz and the base station frequency band is from 27,750 MHz to 28,250 MHz, the band competition rate is 0.5. When the base station frequency band is 28,100 MHz to 28,500 MHz with respect to the satellite frequency band, the band competition rate is 1.

Interference amount calculation unit 124, as the sum of an interference amount i _n from the cells of all the base stations BS in the satellite footprint Pa satellite STa, according to the following equation to calculate the amount of interference I to give the satellite STa.
I = i i _n (n = 1, ..., n _m )
= 10 log (Σ 10 ^{in / 10} ) (n = 1, ..., n _m ) (dBm)
The interference amount calculation unit 124 stores the calculated interference amount I in the storage unit 11.

  The control unit 125 controls conditions for transmitting radio waves from the base station BS to the plurality of mobile terminals MS based on the relationship between the carrier wave level C and the interference amount I. Specifically, the control unit 125 controls the power of radio waves transmitted from the base station BS to the plurality of mobile terminals MS based on the relationship between the carrier level C and the interference amount I, or from the base station BS Control the direction (tilt angle) of transmitting radio waves.

  When the sum of the interference amount I and the estimated amount of the system noise N in the satellite ST is equal to or larger than a predetermined threshold with respect to the carrier level C, the control unit 125 transmits from the base station BS to the plurality of mobile terminals MS. Change the conditions for transmitting radio waves. The control unit 125 calculates the evaluation value E = C / (N + I), and when the evaluation value E is equal to or larger than the threshold, does not change the conditions for transmitting radio waves, and the evaluation value E is smaller than the threshold. It instructs the base station BS to decrease the transmission power of radio waves, or instructs it to change the tilt angle downward. By doing so, it becomes difficult for the radio waves transmitted by the base station BS to reach the satellite ST, so that the amount of interference caused by the radio waves transmitted by the base station BS can be reduced.

Here, the system noise N of the satellite ST is expressed by the following equation. Where K is Boltzmann's constant, T _sys (K) is the system noise temperature of the satellite ST, and B is the satellite bandwidth.
N = kT _sys B = 10 log (kT _sys B) (dBm)
Also, the sum N + I of the noise and the amount of interference is expressed by the following equation.
N + I = 10 log (10 ^{N / 10} + 10 ^{I / 10} ) = ¹⁰ log (kT _sys B + 10 ^{I / 10} ) (dBm)
Therefore, the evaluation value E = C / (N + I) is obtained by the following equation.
E = C / (N + I) = C-(N + I) (dB)

Control unit 125, based on the amount of interference i _n that interference amount calculation unit 124 to calculate the condition that transmits signals to a plurality of mobile terminals MS from at least one of the base stations BS of the plurality of base stations BS _n Control. The control unit 125 selects, for example, a base station BS whose interference amount in is _equal to or greater than a predetermined threshold value, and changes conditions for transmitting radio waves from the selected base station BS to a plurality of mobile terminals MS. Instruct the base station BS that has Control unit 125, among the plurality of base stations BS of the satellite footprint in P satellite ST, instruct to change the conditions for sending a radio wave with respect to interference quantity i _n is greater predetermined number of base stations BS It is also good. Further, the control unit 125 may instruct to change the conditions for transmitting radio waves in order from the base station BS with the largest amount of interference i _n until the evaluation value E becomes equal to or more than a predetermined threshold.

When the base station BS reduces the transmission power of radio waves, the cell of the base station BS is shrunk. As a result, since the distance from the base station BS to the cell edge is reduced, the transmission power of the mobile terminal MS located at the cell edge is reduced. By thus transmitting power of the mobile terminal MS is also reduced, resulting effect that the interference level i _n from the cell decreases. Further, the control unit 125 may cause the base station BS to control the transmission power of the mobile terminal MS whose transmission power is larger than a predetermined value among the mobile terminals MS connected to the base station BS. .

[Operation sequence of base station control system S]
FIG. 4 is a diagram showing an operation sequence of the base station control system S. As shown in FIG.
The base station control server 1 queries the database DB, which manages rainfall data, for rainfall data of the positions of the earth station ES and the base station BS. When acquiring the rainfall data of the position of the earth station ES and the rainfall data of the position of the base station BS, the base station control server 1 stores the acquired rainfall data in the storage unit 11. The first estimation unit 121 and the second estimation unit 122 estimate the amount of rainfall attenuation at the position of the earth station ES and the position of the base station BS based on the acquired rainfall data.

  Also, the base station control server 1 acquires the number of active terminals in the cell of each base station BS and the maximum transmission power value from each base station BS. The base station control server 1 calculates the amount of interference I based on the number of active terminals and the maximum transmission power and the amount of rainfall attenuation at the position of the base station BS. Then, the base station control server 1 evaluates the evaluation value E = C / (N + I) based on the carrier level C, the interference amount I and the noise N in the satellite ST calculated based on the rainfall attenuation amount at the position of the earth station ES. presume.

  The base station control server 1 transmits an instruction to control the transmission power to the base station BS which needs to change the transmission power based on the result of comparing the estimated C / (N + I) with the threshold. The base station BS having received the instruction controls the power to be transmitted to the mobile terminal MS in the cell, and instructs the mobile terminal MS to control the power to be transmitted by the mobile terminal MS. When the base station BS instructs the mobile terminal MS to control the transmission power, the base station BS transmits, to the base station control server 1, an Ack message indicating that the transmission of the instruction has been completed. The base station control server 1 periodically repeats the above procedure.

  FIG. 5 is an operation flowchart of the base station control server 1 according to the present embodiment. The process enclosed in parentheses in FIG. 5 indicates that the same process is repeated for all selection targets. The base station control server 1 repeats the processing from step S4 to step S11 for each combination of the satellite footprint P and the earth station ES.

First, the base station control server 1 selects the satellite footprint P _m (S1). Here, the base station control server 1 is an index indicating the number of earth stations ES in which the quality of the wireless communication channel between the satellite ST and the earth station ES _m does not satisfy the required quality in the selected satellite footprint P _m The value s is initialized to 0 (S2). The index value s is a value indicating the number of earth stations ES exceeding the required C / N in the selected satellite footprint P _m . Subsequently, the base station control server 1 selects the earth station ES _m (S3).

Subsequently, the base station control server 1 calculates the carrier wave level C at the position of the satellite ST that receives the radio wave from the earth station ES _m (S4). The base station control server 1 selects the base station BS _n (S5), for each base station BS _n selected, calculates the interference amount i _n from the cell of the base station BS _n (S6 ). Then, the base station control server 1 calculates the sum I of the interference amounts from all the cells in the satellite footprint P selected in step S1 (S7).

Subsequently, the base station control server 1 calculates C / (N + I), and determines whether the calculated value is smaller than the required C / N (S8). When C / (N + I) is smaller than the required C / N (Yes in S7), the base station control server 1 adds 1 to the index value s (S9). Here, the base station control server 1 determines whether the value of the index value s is larger than the threshold value S (S10). When the index value s is larger than the threshold value S, the base station control server 1 instructs the base station BS _n to lower the transmission power (S11). At this time, the base station control server 1, for example, to instruct the interference amount i _n lowers the transmission power for large base station BS _n than a predetermined threshold value.

When the determination in step S7 and step 10 is No, the base station control server 1 subtracts 1 from the index value s, selects the next earth station, and returns to step S3. The base station control server 1 transmits the base station BS effective for reducing the amount of interference I by repeating steps S4 to S11 with respect to the combination of all the satellite footprints P _m and the earth station ES _m. Power can be reduced.

[Modification]
In the above description, it is assumed that the earth station ES is fixed, but the earth station ES may be movable. In such a case, the base station control server 1 divides the satellite footprint P into a plurality of segments and the processing shown in FIG. 5 on the assumption that one earth station ES is installed in each segment. May be performed.

  Moreover, in the above description, although the 1st estimation part 121 and the 2nd estimation part 122 demonstrated the example which estimates rainfall attenuation based on a rainfall amount, the 1st estimation part 121 and the 2nd estimation part 122 The attenuation may be estimated based on causes other than rainfall. For example, the first estimation unit 121 and the second estimation unit 122 may estimate the amount of attenuation based on interference information indicating an amount of interference given to radio waves, which has been input in advance.

[Effect in the present embodiment]
As described above, the base station control server 1 of the present embodiment estimates the amount of rainfall attenuation based on rainfall data around the earth station ES and the base station BS, and based on the estimation result, the evaluation value E = C /. Calculate (N + I). Then, the base station control server 1 reduces the amount of interference I affecting the satellite ST by controlling the power at which the base station BS transmits radio waves based on the calculated evaluation value E. In this way, the frequency band of the radio wave for transmitting data from the earth station ES to the satellite ST overlaps the frequency band of the radio wave transmitted by the base station BS of the mobile phone network and the mobile terminal MS. Communication quality can be improved. As a result, since the satellite communication and the mobile telephone network can share the frequency, the frequency utilization efficiency is improved.

  Since the base station control server 1 calculates the amount of interference I based on the number of mobile terminals MS transmitting radio waves in the cell of the base station BS, the base station control server 1 has high accuracy according to the number of mobile terminals MS in the cell. Control based on the amount of interference I can be performed.

  Further, the base station control server 1 is a base station to be controlled based on the magnitude of the interference amount I from each of the plurality of base stations BS in the satellite footprint P of the satellite ST. Select BS. By doing this, since the radio waves of the base station BS, which are less effective by changing the conditions of the radio waves to be transmitted, do not decrease, it is possible to prevent the user of the mobile terminal MS from being affected.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It is apparent to those skilled in the art that various changes or modifications can be added to the above embodiment. In particular, the specific embodiment of the distribution and integration of the devices is not limited to the one illustrated above, and all or part of the specific embodiments according to various additions or the like or according to the functional load, in arbitrary units. It can be configured to be distributed or integrated functionally or physically.

1 base station control server 11 storage unit 12 CPU
21 terminal control unit 22 wireless power control unit 121 first estimation unit 122 second estimation unit 123 carrier level calculation unit 124 interference amount calculation unit 125 control unit S base station control system BS base station ES earth station MS mobile terminal DB rainfall database ST satellite

Claims (10)

A first estimation unit configured to estimate a first attenuation amount indicating an attenuation amount of radio waves propagated from the earth station toward the satellite based on a rainfall condition around the earth station in radio communication with the satellite ;
A second estimation unit configured to estimate a second attenuation amount indicating an attenuation amount of radio waves propagated from the base station toward the satellite based on a rainfall condition around a base station that performs wireless communication with a plurality of mobile terminals; ,
A carrier level calculation unit that calculates a carrier level of the satellite in a wireless communication channel between the satellite and the earth station based on the first attenuation amount;
An interference amount calculation unit that calculates an interference amount given to the satellite by at least one of the base station and one or more mobile terminals with which the base station communicates based on the second attenuation amount;
A control unit configured to control a condition for transmitting radio waves from the base station to the one or more mobile terminals based on a relationship between the carrier wave level and the amount of interference;
A base station controller having: The control unit controls the power or direction of radio waves transmitted from the base station to the plurality of mobile terminals, based on the relationship between the carrier wave level and the amount of interference.
The base station controller according to claim 1. The control unit causes the base station to transmit radio waves to the plurality of mobile terminals when the sum of the interference amount and the estimated amount of noise in the satellite is equal to or greater than a predetermined threshold value with respect to the carrier level. Change the conditions to send,
The base station control device according to claim 1 or 2. The control unit is configured to transmit power of radio waves transmitted from the base station to the plurality of mobile terminals when the sum of the interference amount and the estimated amount is equal to or more than a predetermined threshold with respect to the carrier level. Reduce
The base station controller according to claim 3. The interference amount calculation unit calculates the interference amount further based on the number of mobile terminals managed in the cell of the base station or the one or more mobile terminals transmitting radio waves.
The base station controller according to any one of claims 1 to 4. The interference amount calculation unit is an overlapping frequency band in which a second frequency band used for wireless communication by the base station overlaps the first frequency band with respect to a size of a first frequency band used for wireless communication by the satellite. Calculating the amount of interference further based on the ratio of the magnitude of
The base station controller according to any one of claims 1 to 5. The interference amount calculation unit is configured to transmit the plurality of base stations provided in a range where radio waves can reach the satellite, and the plurality of mobile terminals with which the plurality of base stations communicate. Calculate the amount of interference given to
The control unit controls conditions for transmitting radio waves from at least one of the plurality of base stations to the plurality of mobile terminals based on the interference amount calculated by the interference amount calculation unit. ,
The base station controller according to any one of claims 1 to 6 . The control unit changes, among the plurality of base stations, the condition for transmitting radio waves to the plurality of mobile terminals from the base station whose interference amount calculated by the interference amount calculating unit is equal to or greater than a predetermined threshold. Do,
The base station controller according to claim 7 . Estimating a first attenuation amount indicating an attenuation amount of a radio wave propagated from the earth station toward the satellite based on a rainfall condition in the vicinity of the earth station in radio communication with the satellite ;
Estimating a second attenuation amount indicating an attenuation amount of radio waves propagated from the base station toward the satellite based on rainfall conditions in the vicinity of a base station that performs wireless communication with a plurality of mobile terminals;
Calculating a carrier level at the satellite of a wireless communication channel between the satellite and the earth station based on the first attenuation amount;
Calculating an amount of interference given to the satellite by at least one of the base station and one or more mobile terminals with which the base station communicates based on the second attenuation amount;
Controlling conditions for transmitting radio waves from the base station to the one or more mobile terminals based on the relationship between the carrier wave level and the amount of interference;
A base station control method comprising: A base station control system comprising: a base station in radio communication with a plurality of mobile terminals; and a base station control device controlling power of radio waves transmitted by the base station to the plurality of mobile terminals.
The base station controller
A first estimation unit configured to estimate a first attenuation amount indicating an attenuation amount of radio waves propagated from the earth station toward the satellite based on a rainfall condition around the earth station in radio communication with the satellite ;
A second estimation unit configured to estimate a second attenuation amount indicating an attenuation amount of radio waves propagated from the base station toward the satellite based on a rainfall condition around a base station that performs wireless communication with a plurality of mobile terminals; ,
A carrier level calculation unit that calculates a carrier level of the satellite in a wireless communication channel between the satellite and the earth station based on the first attenuation amount;
An interference amount calculation unit that calculates an interference amount given to the satellite by at least one of the base station and one or more mobile terminals with which the base station communicates based on the second attenuation amount;
A control unit that controls conditions for transmitting radio waves from the base station to the one or more mobile terminals based on the relationship between the carrier wave level and the amount of interference;
Have
The base station control system, wherein the base station transmits radio waves to the plurality of mobile terminals based on conditions determined by the control unit.

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