JP2005192023A - Mobile communication equipment and mobile communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile communication system by which elastic change and correction of simultaneous operation of mobile objects which perform formation action are easy. <P>SOLUTION: This mobile communication equipment 20 performs time division multiplexing using time slots allocated to each of the mobile objects 30 in formation 40 and different by every mobile object 30 in the formation 40 by a time division control means. Furthermore, the mobile communication equipment 20 performs code division multiplexing to a signal time division multiplexed by the time division control means using codes different by every formation allocated to each of different formation 40 by a code division control means. In addition, the mobile communication equipment 20 transmits/receives a signal code division multiplexed by the code division control means with output restricted to an extent communicable within a predetermined relative distance range by the code division control means by a transmitting/receiving means. Fixed communication equipment 10 performs adaptive control of orientation of a directional antenna in the direction where the formation 40 exists and communicates with the mobile communication equipment 20 loaded on the mobile object 30 belonging to the formation 40. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to wireless communication between moving objects and wireless communication between a moving object and a fixed station, and more particularly to wireless communication for a flight formation composed of an aircraft.

  Wireless communication is indispensable for the current flight of aircraft. In general passenger aircraft, wireless communication is used for safe operation, and in order to perform effective actions in military and defense flight formations such as fighters (see Non-Patent Document 1, for example).

  FIG. 5 is a diagram illustrating a configuration example of a conventional flight formation communication system. Referring to FIG. 5, the flight formation communication system includes a fixed communication device 910 and a mobile communication device 920. The fixed communication device 910 is installed at a communication station on the ground. Mobile communication device 920 is installed in aircraft 930. The aircraft 930 operates in a flight formation 940 including a plurality of aircraft 930, and communication between the mobile communication devices 920 is frequently performed in the flight formation 940.

  At a ground command post (not shown), the position of a friendly aircraft 930, an enemy aircraft (not shown), or the like is captured by a radar, and an appropriate instruction is given to the flight formation 940. Instructions from the command center are sent from the fixed communication device 910 of the communication station to each aircraft 930 of the flight formation 940. Each aircraft 930 of the flight formation 940 performs an operation action in accordance with instructions from the command post.

  The mobile communication device 920 can communicate with each other and can also communicate with the fixed communication device 910. The mobile communication device 920 employs a large zone system, and the range in which communication is possible is a large zone 950 having a diameter of about several hundred miles. Therefore, the output of the mobile communication device 920 mounted on the aircraft 930 is a large output.

  Further, TDMA is adopted as a multiplexing method in the large zone 950. Prior to flight, a time slot to be assigned to the mobile communication device 920 of each aircraft 930 is determined in advance, and the time slot is set for each mobile communication device 920. By assigning different time slots to each mobile communication device 920, interference in the large zone 950 is prevented.

  The fixed communication device 910 can communicate with each mobile communication device 920 in the large zone 950. The instruction from the command post is sent from the fixed communication device 910 of the communication center to the mobile communication device 920 of each aircraft 930.

In addition, it has been proposed that the flight formation communication system enables not only voice communication but also data communication such as real-time position information captured by a ground radar.
What is LINK-16? System Features ", [online], Division of Professional Development United States Naval Academy, [Search December 2, 2003], Internet, <URL: http: //prodevweb.prodev.usna.edu /SeaNav/NS40x/NS401_old/introduction/html/indexfet.html>

  As the scene of the attack, for example, ground bombing by a large unit consisting of dozens of aircraft is assumed. Usually, the number of aircraft 930 to be attacked is determined in advance, and it is rare that an additional aircraft 930 is urgently added.

  However, a defense situation is mainly envisaged in a country that is dedicated to defense. In the defense scene, usually, the battle power to be input is determined in accordance with the battle power of the enemy captured by the radar. Specifically, for example, the same number of defense aircraft 930 as the enemy aircraft are introduced.

  However, not all of the enemy aircraft from the beginning can be captured by the radar, and enemy aircraft that were not initially captured may be captured later. In addition, enemy aircraft may join from different directions and the number of enemy aircraft may increase. In that case, it is necessary to add a defense aircraft 930 after the fact.

  As described above, normally, one flight formation 940 is composed of a plurality of aircrafts 930, and battles are performed in units thereof, so communication between aircrafts 930 is mainly performed within the flight formation 940. In the large zone 950 having a diameter of several hundred miles, it is assumed that there are a plurality of flight formations 940 in the same zone. In this case, all the mobile communication devices 920 of the aircraft 930 in the same large zone 950 are mutually connected. It was necessary to assign different time slots. In addition, since a plurality of flight formations 940 are introduced in the same zone, it is necessary to manage time slots over a plurality of flight formations 940.

  Therefore, the conventional flight formation communication system is not suitable for elastically changing and correcting the simultaneous operation as in the case of the additional introduction of the aircraft 930. Further, the complicated time slot assignment is not preferable in a scene that requires urgent and does not allow mistakes.

  As an application example of a conventional flight formation communication system, a separate network is formed for each flight formation 940 by combining a CDMA multi-network using frequency hopping spread spectrum (FH-SS) with TDMA in a large zone. Some have been configured to alleviate the complexity of time slot allocation.

  However, the conventional method using frequency hopping requires a synthesizer that can switch frequencies at high speed. Also, in frequency hopping, due to its secrecy, there is a low possibility of information being eavesdropped, but when viewed at a certain moment, a large power level appears at a specific frequency, so it is detected by the enemy that some kind of communication is taking place. There was a possibility.

  An object of the present invention is to provide a mobile communication system that uses a relatively narrow frequency band and can easily change or modify the simultaneous operation of mobile bodies that perform formation operations.

In order to achieve the above object, a mobile communication device of the present invention is a mobile communication device mounted on each of the mobile bodies belonging to a formation composed of at least one mobile body acting within a predetermined relative distance range. ,
Time-division control means for performing time-division multiplexing using a different time slot for each mobile body in the formation, assigned to each of the mobile bodies in the formation;
Code division control means for performing code division multiplexing on a signal time-division multiplexed by the time division control means, using a different code for each of the formations assigned to each of the different formations;
Transmitting / receiving means for transmitting / receiving a signal that has been code division multiplexed by the code division control means, with an output limited to such an extent that communication is possible within the predetermined relative distance range.

  Therefore, according to the present invention, time division multiplexing is performed by assigning a different time slot to each mobile body in the formation, code division is performed by assigning a different code to each of the different formations, and time division multiplexing is performed. Combining code division multiplexing, it is possible to communicate with each other between mobile communication devices mounted on each mobile unit in the formation.

  In addition, according to the present invention, the output of the mobile communication device is limited to such an extent that communication can be performed within the relative distance range where each mobile body of the formation exists.

  The code division control means may perform spread spectrum using the code on the signal time-division multiplexed by the time division control means.

  Therefore, since the mobile communication device performs spread spectrum communication using a code assigned to each of the formations, it has high secrecy.

  The spread spectrum may be a direct diffusion type.

  Therefore, since the mobile communication device performs direct spread spectrum spread spectrum communication using a code assigned to each of the formations, a synthesizer capable of switching the frequency at a higher speed than the frequency hopping spread spectrum communication is required. And not. Further, in the direct spread type spread spectrum communication, since the signal used for communication appears at a low power level in a wide frequency band, the possibility of detecting that communication is being performed is lower than that in the frequency hopping type. .

  The mobile body may be an aircraft, and the formation may be a flight formation including the aircraft.

The mobile communication system of the present invention includes any one of the mobile communication devices of the present invention described above,
You may have the fixed communication apparatus which adaptively controls the directivity direction of a directional antenna in the direction where the said formation exists, and communicates with the mobile communication apparatus mounted in the mobile body which belongs to this formation.

  Therefore, the fixed communication device can communicate with the mobile communication device using the directional antenna.

In addition, there are a plurality of the formation and the fixed communication device,
A combination of the formation and the fixed communication device is selected so that a plurality of the formations in the same direction as viewed from each of the fixed communication devices do not simultaneously become communication partners of the fixed communication device, and the mobile communication is performed based on the combination. The apparatus and the fixed communication apparatus may communicate with each other.

  Therefore, the mobile communication device selects the fixed communication device that communicates with each of the plurality of formations so that the plurality of formations in the same direction as viewed from each fixed communication device do not become communication partners of the fixed communication device. Interference is unlikely to occur in the communication of the fixed communication device.

  According to the present invention, time division multiplexing is performed by assigning different time slots to each mobile unit in the formation, code division is performed by assigning different codes to each of the different formations, and each mobile unit in the formation is performed. Communicating with each other between the mobile communication devices mounted on the mobile, and combining the time division multiplexing and code division multiplexing to communicate with each other between the mobile communication devices mounted on each mobile unit in the formation. When assigning time slots to the body, it is not necessary to consider other formations, time slot management is easy, and interference does not occur even if the formations approach each other.

  In addition, according to the present invention, the output of the mobile communication device is limited to the extent that communication can be performed within the relative distance range in which each mobile unit of the formation exists, so communication within the formation is realized with low power consumption. In addition, the mobile communication device can be reduced in size and weight.

  Also, since the mobile communication device performs spread spectrum communication using codes assigned to each of the formations, it has high confidentiality.

  In addition, since the mobile communication apparatus performs direct spread spectrum spread communication using a code assigned to each of the formations, a synthesizer capable of switching frequencies at a higher speed than the frequency hopping spread spectrum communication is required. It is easy to implement and low cost.

  Also, since direct spread type spread spectrum communication is used, the signal used for communication appears at a low power level in a wide frequency band, so communication is performed compared to the conventional type using frequency hopping type. Therefore, it is possible to perform communication with higher safety.

  Further, since the fixed communication device communicates with the mobile communication device using the directional antenna, communication between the mobile body and the fixed communication device is possible even when the fixed communication device is outside the predetermined relative distance range of the formation.

  In addition, the mobile communication device selects the fixed communication device that communicates with each of the plurality of formations so that the multiple formations in the same direction as viewed from each fixed communication device do not become communication partners of the fixed communication device. Interference is unlikely to occur in the communication of the fixed communication device and communication can be performed satisfactorily.

  An embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a configuration of a flight formation communication system according to an embodiment of the present invention. Referring to FIG. 1, the flight formation communication system includes a fixed communication device 10 and a mobile communication device 20. The fixed communication device 10 is installed at a communication station on the ground. The mobile communication device 20 is installed on the aircraft 30. The aircraft 30 operates in a flight formation 40 composed of a plurality of aircraft 30, and communication between the mobile communication devices 20 is frequently performed in the flight formation 40.

  At the ground command post (not shown), the positions of the friendly aircraft 30 and enemy aircraft (not shown) are captured by the radar, and appropriate instructions are given to the flight formation 40. The instruction from the command post is sent to each aircraft 30 of the flight formation 40 from the fixed communication device 10 of the communication center. Each aircraft 30 of the flight formation 40 executes a strategy action in accordance with instructions from the command post.

  The mobile communication device 20 can communicate with each other and can also communicate with the fixed communication device 10. The mobile communication device 20 adopts a small zone method, and the diameter of the small zone 50 is limited to a distance that can cover the relative distance during the flight action between all the aircrafts 30 of the same flight formation 40. Therefore, the output of the mobile communication device 20 mounted on the aircraft 30 is a small output. Moreover, since the relative position of the aircraft 30 changes depending on the flight behavior, an omnidirectional antenna is used. Thus, the aircrafts 30 of the same flight formation 40 can always communicate with each other during the flight action.

  As a radio signal multiplexing system, a system combining a TDMA system and a CDMA system is employed.

  A TDMA system is adopted as a multiplexing system in each small zone 50. Prior to flight, a time slot assigned to the mobile communication device 20 of each aircraft 30 in the flight formation 40 is determined in advance, and the time slot is set for each mobile communication device 20. Thereby, the mobile communication devices 20 of the aircrafts 30 in the flight formation 40 can identify each other and perform communication.

  Each flight formation 40 is divided by the CDMA method, and each flight formation 40 is given a unique code in advance. The radio signal is obtained by performing spread spectrum (DS-SS) on the TDMA signal in the flight formation 40 by direct spreading using a code for each flight formation 40.

  A plurality of flight formations 40 may fly in the same airspace at the same time, and the relative distance between the flight formations 40 varies depending on the flight behavior. However, since the codes are divided by the CDMA method, interference between the flight formations 40 occurs. Hard to do. Even when the aircraft 30 is additionally introduced into the same or adjacent airspace, the addition is performed in units of the flight formation 40, and it is only necessary to assign a unique code to the flight formation 40. Considering the time slots assigned to other aircraft 30 that are already in flight as in the prior art, there is no need to assign time slots to the additional aircraft 30 before the flight, which is easy and urgent. Suitable for start of flight.

  The fixed communication device 10 can communicate with each mobile communication device 20 in each small zone 50. The instruction from the command post is sent from the fixed communication device 10 at the communication center to the mobile communication device 20 of each aircraft 30. Since the output of the mobile communication device 20 is suppressed to such an extent that it can communicate non-directionally in the flight formation 40, the fixed communication device 10 uses a directional antenna that exhibits high gain directivity characteristics in a narrow range, and its directivity By controlling the sex in the direction of the flight formation 40, it communicates with the mobile communication device 20 of each aircraft 30.

  FIG. 2 is a block diagram showing a configuration of the mobile communication device. Referring to FIG. 2, the mobile communication device 20 includes a transmission / reception unit 21, an SSDS (spread spectrum-direct spread) control unit 22, a TDMA control unit 23, a coupler 24, an aircraft interface 25, and an aircraft antenna terminal 26. . The transmission / reception unit 21 includes a reception unit 211 and a transmission unit 212. The SSDS control unit 22 includes an SSDS demodulation unit 221 and an SSDS modulation unit 222. Airframe antenna terminal 26 is connected to airframe antenna 27.

  The receiving unit 211 sends the radio signal received by the airframe antenna 27 to the SSDS demodulating unit 221. At that time, the reception unit 211 performs amplification by LNA (low noise amplifier), frequency conversion from radio frequency to baseband, filtering, and the like.

  The SSDS demodulation unit 221 performs an SSDS demodulation process on the signal from the reception unit 211 and sends the signal to the TDMA control unit 23. The SSDS demodulation process includes, for example, despreading, carrier reproduction, data demodulation, and the like. In the despreading process, a code assigned to the flight formation 40 to which the aircraft 30 in which the mobile communication device 20 is installed belongs.

  The SSDS modulation unit 222 performs an SSDS modulation process on the signal from the TDMA control unit 23 and sends the signal to the transmission unit 212. The SSDS modulation process includes, for example, data modulation and spreading. In this spreading process, a code assigned to the flight formation 40 to which the aircraft 30 in which the mobile communication device 20 is installed belongs.

  The transmission unit 212 converts the spread signal from the SSDS modulation processing unit 222 into a radio signal and transmits it from the body antenna 28.

  The TDMA control unit 23 extracts a signal in a predetermined time slot of the signal from the SSDS demodulation unit 221 (message depacking) and sends it to the machine interface 25. This time slot is a time slot unique to the flight formation 30 assigned to the mobile communication device 20. Further, the TDMA control unit 23 inserts a signal from the machine interface 25 into a predetermined time slot (message packing), and sends it to the SSDS demodulation unit 22. This time slot is also a time slot unique to the flight formation 30 assigned to the mobile communication device 20.

  The TDMA control unit 23 performs TDMA synchronization management at a timing common to all the mobile communication devices 20 of the aircraft 30.

  Airframe interface 25 is connected to each device (not shown) installed in the airframe, and transmits / receives device signals specific to each device. For example, an audio signal is transmitted and received if the device is used for audio communication. If it is a device for position display, a position information signal indicating the position of a friendly aircraft, enemy aircraft, base, etc. is transmitted and received. If it is various sensor apparatuses, the sensor signal which shows the state of each part will be transmitted / received. Physical and electrical interfaces are defined between each device.

  FIG. 3 is a block diagram illustrating a configuration of the fixed communication device. Referring to FIG. 3, the fixed communication device 10 includes a TDMA control unit 31, an SSDS control unit 32, a transmission / reception unit 33, a coupler 34, a directional antenna 35, and a directivity control unit 36.

  The directional antenna 35 is a directional antenna capable of controlling the directional direction. In order to communicate with the mobile communication device 20 that communicates between the aircrafts 30 belonging to the flight formation 40 within the small zone 50 and the fixed communication device 10 outside the small zone 50, the fixed communication device 10 has a high gain in the pointing direction. A directional antenna 35 is used. The directional antenna 35 may be, for example, an adaptive array antenna.

  The directivity control unit 36 adaptively controls the directivity direction of the directional antenna 35 to the direction of the flight formation 40 that is a communication partner. The direction of the flight formation 40 may be given to the directing control unit 36 from, for example, a radar (not shown).

  The receiving unit 331 sends the radio signal received by the directional antenna 35 to the SSDS demodulating unit 321. At that time, the receiving unit 331 performs amplification by LNA, frequency conversion from radio frequency to baseband, filtering, and the like.

  The SSDS demodulator 321 performs an SSDS demodulation process on the spread signal from the receiver 331 and sends it to the TDMA controller 31. The SSDS demodulation process includes, for example, despreading, carrier reproduction, data demodulation, and the like. For this despreading process, a code assigned to the flight formation 40 of the communication partner is used.

  The SSDS modulation unit 322 performs an SSDS modulation process on the signal from the TDMA control unit 31 and sends the signal to the transmission unit 332. The SSDS modulation process includes, for example, data modulation and spreading. In this spreading process, a code assigned to the flight formation 40 of the communication partner is used.

  The transmission unit 332 transmits the signal from the SSDS modulation processing unit 322 from the directional antenna 35.

  The TDMA control unit 31 takes out a signal of a predetermined time slot from the SSDS demodulation unit 321 and outputs it to the command post. This time slot may be a time slot unique to the flight formation 30 assigned to the mobile communication device 20 of the communication partner, or a multicast time received by the mobile communication devices 20 of all the aircrafts 30. It may be a slot.

  Further, the TDMA control unit 31 inserts a signal input from the command post into a predetermined time slot (message packing) and sends the signal to the SSDS modulation unit 322. This time slot may also be a time slot unique to the flight formation 30 assigned to the mobile communication device 20 of the communication partner, or may be a multicast time slot.

  The TDMA control unit 31 performs TDMA synchronization management at the same timing as the mobile communication devices 20 of all the aircrafts 30.

  As described above, according to the present embodiment, the small zone method is adopted, and the output of the mobile communication device 20 is within the small zone 50 corresponding to the flight formation 40 that requires mutual communication between the aircrafts 30. Since communication is limited to the extent that communication is possible, communication in the flight formation 40 can be realized with low power consumption, and the mobile communication device 20 can be reduced in size and weight.

  In addition, time division multiplexing is performed by assigning different time slots to each aircraft 30 of one flight formation 40 in the small zone 50, and code division is performed by assigning different codes to different flight formations 40. Since communication is performed between the mobile communication devices 20 mounted on the aircrafts 30 in the flight formation 40, it is not necessary to consider other flight formations 40 when assigning time slots to the aircrafts 30, and time slot management is easy. In addition, even if the flight formations 40 approach each other, it is difficult for interference to occur.

  Further, since the mobile communication device 20 performs spread spectrum communication using a code assigned to each of the flight formations 40, the confidentiality is high.

  Further, since the mobile communication device 20 performs direct spread type spread spectrum communication using a code assigned to each of the flight formations 40, it is possible to perform frequency switching faster than frequency hopping type spread spectrum communication. It does not require a synthesizer and is easy to implement and low cost. Also, since direct spread type spread spectrum communication is used, the signal used for communication appears at a low power level in a wide frequency band, so communication is performed compared to the conventional type using frequency hopping type. Therefore, it is possible to perform communication with higher safety.

  1 illustrates the case where there is one fixed communication device 10, but the present invention is not limited thereto, and a plurality of fixed communication devices 10 may exist. FIG. 4 is a diagram illustrating a state of communication when there are a plurality of fixed communication apparatuses.

Referring to FIG 4, ₁ two fixed communication apparatus 10 that is fixedly installed on the ground, and 10 _2, an example in which three small zones 50 _{1-50 3} maritime airspace exists is shown. For small zone 50 ₂ and the small zones 50 ₃ in the same direction as viewed from the fixed communication apparatus 10 _2, the use of fixed communication apparatus 10 ₂ to communicate with these small zones 50 _2, 50 ₃ flight formation, both In this communication, the directivity direction of the directional antenna 35 is controlled in the same direction, and one desired wave becomes the other interference wave. Therefore, there arises a disadvantage that it is difficult to obtain a sufficient S / N ratio in spread spectrum communication.

Therefore, it is necessary to appropriately select the fixed communication device 10 that communicates with the flight formation 40, that is, the flight formation 40 in a plurality of small zones 50 that are in the same direction as viewed from one fixed communication device 10 has its fixed communication. It is necessary not to be a communication partner of the device 10. In the example of FIG. 4, the fixed communication device 10 ₁ communicates with the two flight formations 40 in the small zones 50 ₂ and 50 ₃ , and the fixed communication device 10 ₂ communicates with the flight formation 40 in the small zone 10 ₁ .

  As a result, the flight formations 40 in the plurality of small zones 50 that are in the same direction as viewed from each fixed communication device 10 communicate with each of the plurality of flight formations 40 so that they do not become communication partners of the fixed communication device 10. Since the fixed communication device 10 is selected, interference between the mobile communication device 20 and the fixed communication device 10 hardly occurs, and spread spectrum communication can be performed satisfactorily.

  There are various methods for determining in which small zone 50 the flight formation 40 each fixed communication device 10 communicates. However, the fixed communication device 10 may determine the information by mutually exchanging information. For example, each fixed communication device 10 mutually notifies the distance information with each of the flight formations 40, and at this time, information on the flight formations 40 that cannot be made by the communication partner because they are in the same direction as viewed from itself. It is sufficient to notify each other at the same time. For each flight formation 40, the fixed communication device 10 that can be a communication partner and has the shortest distance only needs to be the communication partner of the flight formation 40.

  In addition, a high-order device that determines which small zone 50's flight formation 40 communicates with each fixed communication device 10 may be provided separately, and each fixed communication device 10 may follow an instruction from the high-order device.

It is a figure which shows the structure of the communication system for flight formations by one Embodiment of this invention. It is a block diagram which shows the structure of a mobile communication apparatus. It is a block diagram which shows the structure of a fixed communication apparatus. It is a figure which shows the mode of communication when multiple fixed communication apparatuses exist. It is a figure which shows the structural example of the communication system for conventional flight formations.

Explanation of symbols

10, 10 ₁ , 10 ₂ Fixed communication device 20 Mobile communication device 21 Transmission / reception unit 211 Reception unit 212 Transmission unit 22 SSDS control unit 221 SSDS demodulation unit 222 SSDS modulation unit 23 TDMA control unit 24 Coupler 25 Machine interface 26 Machine antenna terminal 27 Machine Antenna 30 Aircraft 31 TDMA control unit 32 SSDS control unit 321 SSDS demodulation unit 322 SSDS modulation unit 33 Transmission / reception unit 331 Reception unit 332 Transmission unit 34 Coupler 35 Directional antenna 36 Direction control unit 40 Flight formation 50, 50 ₁ to 50 ₃ Small zone

Claims (6)

A mobile communication device mounted on each of the mobile bodies belonging to a formation consisting of at least one mobile body acting within a predetermined relative distance range,
Time-division control means for performing time-division multiplexing using a different time slot for each mobile body in the formation, assigned to each of the mobile bodies in the formation;
Code division control means for performing code division multiplexing on a signal time-division multiplexed by the time division control means, using a different code for each of the formations assigned to each of the different formations;
A mobile communication apparatus comprising: a transmission / reception unit configured to transmit / receive a signal that has been code division multiplexed by the code division control unit, with an output limited to a level that allows communication within the predetermined relative distance range. The mobile communication apparatus according to claim 1, wherein the code division control means performs spread spectrum using the code on the signal time-division multiplexed by the time division control means. The mobile communication device according to claim 2, wherein the spread spectrum is a direct spread type. The mobile communication device according to claim 1, wherein the mobile body is an aircraft, and the formation is a flight formation including the aircraft. The mobile communication device according to any one of claims 1 to 4,
A mobile communication system comprising: a fixed communication device that adaptively controls a directivity direction of a directional antenna in a direction in which the formation exists and communicates with a mobile communication device mounted on a mobile body belonging to the formation. A plurality of the formation and the fixed communication device respectively exist,
A combination of the formation and the fixed communication device is selected so that a plurality of the formations in the same direction as viewed from each of the fixed communication devices do not simultaneously become communication partners of the fixed communication device, and the mobile communication is performed based on the combination. The mobile communication system according to claim 5, wherein an apparatus and the fixed communication apparatus communicate with each other.

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