JP4624281B2 - Mobile communication terminal and communication control method - Google Patents

Description

  The present invention relates to a mobile communication terminal such as a mobile phone, and more particularly to a technique for detecting the movement status of a mobile communication terminal.

  In mobile communication, there is a concern about influence on wireless communication due to movement of a terminal. Specifically, for example, the influence of radio wave intensity fluctuation (fading) accompanying the movement state of the mobile communication terminal, the influence of multipath due to reflected waves and refracted waves, and the influence due to frequency fluctuation (Doppler shift etc.) can be mentioned. Conventionally, communication is stabilized by reducing or correcting these factors.

  In addition to improving the wireless communication situation, a communication technique for improving the communication speed has been proposed. Typical examples include improvement of the modulation method and the use of a plurality of wireless communication paths, both of which have achieved certain results with respect to improving the communication speed.

  By the way, although the communication technique aiming at the improvement of communication speed is contrary to the stability of communication, in order to provide a user with comfortable wireless communication, it is required to balance both. In response to this requirement, conventionally, a technique has been proposed in which an optimum communication method is selected according to the movement state of the mobile communication terminal.

As the above technique, for example, in Patent Document 1 described later, there is a technique in which a base station observes the intensity of a radio wave from a mobile station and determines a handover destination of the mobile station according to a movement situation determined from the result. Proposed. Patent Document 2 described later proposes a technique in which a GPS (Global Positioning System) receiver is mounted on a mobile communication terminal, and communication is performed by correcting a Doppler shift calculated based on the position information of the terminal. Has been.
JP-A-10-248090 JP 2001-119333 A

  According to the method disclosed in Patent Document 1, it is possible to cope with high-speed movement of the terminal. However, recently, for the purpose of effective use of radio resources, a radio network may be intentionally constructed so that base stations with low radio output and base stations with high radio output are mixed. In such an environment, the intensity of the radio wave cannot be properly observed, and it is difficult to appropriately determine the movement status of the terminal.

  Moreover, although the method of the said patent document 2 can grasp | ascertain the movement condition of a terminal simply using GPS, from the viewpoint of the cost reduction and power saving of a terminal, the GPS reception function is carried in the terminal. It is not preferable to do.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique for appropriately and easily determining the movement status of a terminal in mobile communication.

Mobile communication terminal according to the present invention includes: a movement information generation section for generating movement information indicating the communication status of the terminal, and a transceiver for transmitting and receiving radio signals with the radio base station by a communication format based on the movement information wherein the movement information generation section comprises: a means for determining the variation represented by the subsequent history records a history of the difference between the frequency of the prescribed frequency of the radio signal received from the radio base station as the moving information, the provision Means for recording a history of a difference between a reception start timing and a reception timing from the radio base station, and obtaining a fluctuation amount represented by the history as the movement information , wherein the transmission / reception unit is based on the movement information And a means for switching the communication format according to the result of the determination.

  The mobile communication terminal according to the present invention includes a mobile information generating unit that generates mobile information indicating the communication status of the mobile terminal, and a transmitting / receiving unit that transmits and receives radio signals to and from a radio base station using a communication format based on the mobile information. The movement information generation unit includes a means for recording a history of a difference between a prescribed reception start timing and a reception timing from the radio base station, and obtaining a variation amount represented by the history as movement information. The unit includes means for determining the movement status of the terminal based on the movement information and switching the communication format according to the determination result.

  According to the present invention, since the movement information that serves as a communication format selection criterion is created based on the communication frequency and the reception delay, the movement status of the own terminal can be easily determined without mounting a position measurement device such as a GPS receiver. Can be determined. Further, even in a communication network that intentionally mixes communication with different radio field intensities, it is possible to appropriately determine whether or not the terminal is moving.

  FIG. 1 shows a basic configuration of an embodiment of a mobile communication terminal according to the present invention. The mobile communication terminal 100 of the embodiment includes a transmission / reception unit 100A that transmits / receives a radio signal to / from a radio base station, and a movement information generation unit 100B that generates movement information indicating the communication status of the terminal itself. The transmission / reception unit 100A and the movement information generation unit 100B are constituent elements of a functional concept including the hardware and software of the mobile communication terminal 100.

  FIG. 2 shows a configuration of the first embodiment based on the above configuration. The mobile communication terminal 101 of the present embodiment includes a communication device 11 that performs signal processing such as encoding and decoding of a radio signal to be transmitted and received, a communication control device 12 that controls a wireless communication format, and a wireless communication via an antenna 15. A transmission circuit 13 and a reception circuit 144 that transmit and receive signals are provided. These are components corresponding to the transmitting / receiving unit 100A shown in FIG. Note that the communication device 11, the transmission circuit 13, the reception circuit 144, and the antenna 15 are the same as those included in the conventional mobile communication terminal, and detailed descriptions thereof are omitted.

  Further, the mobile communication terminal 101 includes a frequency detection device 21, a frequency deviation detection device 22, and a frequency fluctuation observation device 23 as shown in FIG. These are components corresponding to the movement information generation unit 100B shown in FIG.

  The frequency detection device 21 specifies the frequency of the radio wave received from the radio base station. The frequency deviation detection device 22 acquires the frequency deviation of the communication radio wave notified from the radio base station from the communication control device 12, and detects the frequency deviation by detecting the difference between this and the frequency specified by the frequency detection device 21. taking measurement. The frequency fluctuation observation device 23 creates frequency fluctuation data by sequentially recording the measurement results of the frequency deviation detection device 22. This frequency variation data is recognized by the communication control device 12 as movement information.

  The communication control device 12 determines the movement status of the own terminal based on the frequency variation data as the movement information, and adaptively switches the communication algorithm, the modulation format, etc. according to the result. For example, PSK (Phase Shift Keying), which emphasizes the stability of communication, and QAM (Quadrature Amplitude Modulation), which aims to increase the communication speed, can be used to switch the modulation format. There are switching and so on. Specific switching processing will be described later.

  Hereinafter, the operation of this embodiment will be described. First, the radio frequency used for communication is set in the communication control device 12. It is assumed that this frequency is fixedly set as known, or dynamically set by negotiation with a radio base station when starting communication. In either case, the communication control device is always set. The frequency is set to 12.

  According to a prescribed radio frequency set in the communication control device 12, the transmission circuit 13 and the reception circuit 144 transmit and receive radio waves by the antenna 15, and the communication device 11 performs signal processing for voice communication and data communication. Further, information regarding the prescribed frequency is notified to the frequency deviation detecting device 22 at the start of communication.

  With reference to the flowchart shown in FIG. 3, the process by the frequency detection device 21, the frequency deviation detection device 22, and the frequency variation observation device 23 as the movement information generation unit (100B) will be described. When the wireless communication is started, the frequency deviation detecting device 22 recognizes the frequency information notified from the communication control device 12 for a specified wireless frequency (S1).

On the other hand, the frequency detection device 21 analyzes the frequency distribution of the radio wave received by the receiving circuit 144 and identifies the frequency of the radio wave (S2). FIG. 4 shows an example of the frequency distribution of received radio waves. Assuming that the radio wave received by the receiving circuit 144 has a distribution as shown in the figure, the frequency detection device 21 detects the frequency f ₁ having the highest intensity. This frequency f ₁ is set as the frequency of the radio wave received this time.

The frequency deviation detection device 22 obtains a deviation Δf with respect to the specified frequency f ₀ previously notified from the communication control device 12 for the frequency f ₁ specified by the frequency detection device 21 (S3). In general, when a Doppler shift or the like due to the movement of the mobile communication terminal 101 occurs, a significant deviation occurs between the specified frequency (f ₀ ) and the frequency (f ₁ ) of the received radio wave. The example shown in FIG. 4 is an example in which the frequency f _{1 of the} received radio wave is lower than the specified frequency f ₀ by the deviation Δf.

  The frequency fluctuation observation device 23 creates frequency fluctuation data as movement information by recording the frequency deviation Δf obtained by the frequency deviation detection device 22 in time series (S4). FIG. 5 schematically shows the frequency variation data. When the position of the mobile communication terminal 101 is small and there is almost no movement, the frequency deviation Δf is small. Therefore, in this case, as time period A shown in the figure, the amount of fluctuation over time is moderate. On the other hand, when the mobile communication terminal 101 moves, the frequency deviation Δf increases, and as a result, the amount of fluctuation with time increases as in the period B shown in the figure.

  In addition, as a specific method of recording the temporal change of the frequency deviation Δf, for example, the fluctuation state is sequentially calculated using a differentiating circuit, or the deviation fluctuation amount (minimum value and maximum value at each unit observation time). The method of calculating the difference between the two is conceivable. These are conventionally known analysis methods and will not be described.

  In the present embodiment, the frequency fluctuation data is notified to the communication control apparatus 12 by the frequency fluctuation observation apparatus 23 in this embodiment, but instead, the communication control apparatus 12 periodically transmits to the frequency fluctuation observation apparatus 23. An inquiry may be made, or the communication control device 12 may periodically access a storage device (not shown) in the mobile communication terminal 101.

  Next, communication format switching processing by the communication control device 12 will be described. Here, as an example, the switching target is a modulation format. More specifically, PSK (Phase Shift Keying) that emphasizes communication stability is applied while the mobile communication terminal 101 is moving, and QAM (Quadrature Amplitude) is used to speed up communication when the mobile communication terminal 101 is not moving. Apply modulation. In this way, by applying PSK while the terminal is moving and applying QAM while there is no movement, it is possible to prevent deterioration in communication quality that is likely to occur during movement, and to reduce the communication speed while there is no movement. It is possible to perform adaptive communication control for improvement.

  When switching the modulation format as in the present example, it is assumed that the base station communicating with the mobile communication terminal 101 can cope with the switching. That is, it is a premise that when the mobile communication terminal 101 actively switches the modulation format, the base station side recognizes it.

  A conventionally known method can be used as the above mechanism. For example, when switching the modulation format, there is a method of notifying the fact to the base station by a control message. Alternatively, the base station may receive radio waves from the mobile station in a plurality of modulation formats and recognize a modulation format that can be properly received as the current modulation format. In this case, it is not necessary for the mobile station to notify the base station in advance of switching of the modulation format.

  The procedure of the switching process will be described with reference to the flowchart shown in FIG. When the communication control device 12 recognizes the frequency variation data created by the frequency variation observation device 23 (S11), the communication control device 12 determines whether or not it represents the movement of the own terminal (101).

  In the above determination, for example, during a period when the fluctuation amount of the frequency deviation Δf exceeds a predetermined range (Δ− to Δ +) or when the frequency exceeds the predetermined value as in the period B shown in FIG. Then, it is determined that the own terminal is moving. The criteria for determination are not limited to these and can be set as appropriate.

  If it is determined that the terminal is moving (S12: Yes), the communication control device 12 determines whether the current modulation format should be applied while the terminal is moving, that is, the current PSK. Check whether or not. As a result, if the current state is PSK (S13: Yes), it is maintained, and the processing proceeds to the next frequency variation data processing. If the current is QAM instead of PSK (S13: No), the modulation format is switched from QAM to PSK (S14).

  If it is determined that the terminal is not moving (S12: No), the communication control device 12 checks whether the current modulation format is QAM (S15), and if it is PSK, Switch to QAM (S16).

  Note that the communication format switching target is not limited to the above-described PSK and QAM, and other types can be targeted. When the terminal is not moving, a modulation scheme or a communication algorithm for improving the communication speed is applied, and thereby further improvement of the communication speed is expected. Conversely, when the terminal is moving, the use of a modulation scheme or communication algorithm that is resistant to noise, fading, etc. can improve the communication stability during movement. In this way, by controlling the communication format according to the movement state of the terminal, it is possible to improve both the communication stability during movement in mobile communication and the communication high speed when the terminal is stopped.

  According to the first embodiment described above, since the movement information that is the selection standard of the communication format is created based on the communication frequency, it is simple and appropriate without mounting a position measuring device such as a GPS receiver. The presence / absence of movement of the terminal can be determined.

  In addition, since this embodiment uses a so-called carrier frequency defined between a terminal and a base station in general mobile communication, it can be applied to any mobile communication regardless of the communication mode between them. is there. However, in the case of communication modes in which the carrier frequency is dynamically changed, such as frequency division multiple access (FDMA) and frequency hopping (FHSS), the current communication frequency is sequentially updated based on the frequency information from the base station. do it.

  FIG. 7 shows the configuration of the second embodiment of the present invention. The mobile communication terminal 102 of the present embodiment applies TDMA (Time Division Multiple Access) as a radio signal multiplexing format. The difference in configuration between this mobile communication terminal 102 and the above-described mobile communication terminal 101 shown in FIG. 2 is as follows. The other components are the same as those in FIG.

  For TDMA communication, the transmission / reception unit 100A of the mobile communication terminal 102 includes a synchronization detection unit 16 that detects synchronization control information (preamble) from the received radio signal in the reception circuit 144. Further, the communication control device 12 is provided with a timer 17 for measuring a time slot that is a preset period for the transmission / reception operation.

  As the time slot, a fixed value or a value dynamically set by negotiation with the radio base station at the start of communication is assumed. Information on the time slot to be applied is set. The communication control device 12 measures a prescribed time slot by the timer 17 and controls the timing of transmission / reception operations by the transmission circuit 13 and the reception circuit 14 according to the time slot.

  The movement information generation unit 100B of the mobile communication terminal 102 includes a delay time measurement device 24 and a delay variation observation device 25 as shown in FIG. The delay time measuring device 24 measures the delay time (Δt) of the received frame based on the reception timing signal from the timer 17 based on the time slot and the synchronization detection signal from the synchronization detection unit 16 based on the received frame. Based on the measurement result of the delay time measuring device 24, the delay variation observing device 25 creates delay variation data representing the variation over time of the reception delay. This delay variation data corresponds to the movement information according to the present invention.

  The communication control device 12 according to the present embodiment determines whether or not the mobile communication terminal 102 has moved based on delay variation data as movement information, and switches the communication format according to the result. As the switching target, for example, the number of time slots in TDMA communication can be used. Specific switching processing by the communication control device 12 will be described later.

  The operation of this embodiment will be described. The receiving circuit 14 repeats the operation of starting and stopping the reception at a predetermined cycle according to the time slot managed by the timer 17 of the communication control device 12. The reception circuit 14 reconstructs a transmission frame from the received radio wave, and the synchronization detection unit 16 detects synchronization control information included therein.

  Hereinafter, processing by the delay time measuring device 24 and the delay variation observing device 25 as the movement information generating unit (100B) of the present embodiment will be described with reference to the flowchart shown in FIG.

  The delay time measuring device 24 recognizes the reception timing signal from the timer 17 based on the time slot and the synchronization control signal from the synchronization detection unit 16 based on the received transmission frame (S21). Then, a reception delay time (Δt) is obtained by calculating the time difference between the two (S22).

FIG. 9 schematically shows the concept of the reception delay time Δt. As shown in FIG. 9, the transmission circuit 13 and reception circuit 14, respectively repeated transfer operations at a given time slot TS _0. Here, focusing on one time slot TS ₀ of the reception operation, the reception delay time Δt detects synchronization control information of the transmission frame received in the time slot from the reception start timing in the time slot TS ₀ . It took time until

FIG. 10 schematically shows the relationship between the distance between the base station and the mobile station and the reception delay time Δt. Since the reception delay time Δt is related to the arrival time of radio waves from the base station to the mobile station, the value theoretically increases as the position of the mobile station becomes farther from the base station. Therefore, as shown in FIG. 10, when the delay times Δt ₁ and Δt ₂ are in the relationship of “Δt ₁ <Δt ₂ ”, the delay time Δt ₁ is greater than the time when the delay time Δt ₁ is detected. The time Δt ₂ means that the mobile station is located farther from the base station.

  The delay variation observation device 25 creates delay variation data by recording the reception delay time Δt measured by the delay time measurement device 24 in time series (S23). FIG. 11 schematically shows an example of delay variation data. When the position change of the mobile communication terminal 102 with respect to the radio base station is small and there is almost no movement, the fluctuation amount of the delay time Δt is small. Therefore, in this case, as time period A shown in the figure, the change over time is moderate. On the other hand, when the mobile communication terminal 102 moves, the distance from the base station changes, so that the amount of change in the delay time Δt increases, and as a result, the change over time increases as in the period B shown in the figure.

  As a specific method of recording the temporal change of the delay time Δt, for example, the fluctuation state is sequentially calculated using a differentiation circuit, or the fluctuation amount (difference between the minimum value and the maximum value) is calculated for each unit observation time. A conventionally known analysis method such as calculation is used.

  Regarding the handling of delay variation data in the mobile communication terminal 102, as in the case of the frequency variation data in the first embodiment described above, a mechanism for notifying the communication controller 12 from the delay variation observation device 25, or communication control A mechanism that the apparatus 12 periodically inquires and acquires is appropriately used.

  When the communication control device 12 recognizes the delay variation data related to the reception delay time Δt, the communication control device 12 determines whether or not it indicates the movement of the mobile communication terminal 102. This determination is performed in the same manner as the determination process in the first embodiment described above. That is, as shown in FIG. 11, a predetermined range (Δ− to Δ +) is set for the delay time Δt, and the moving amount is not moving as long as the fluctuation amount is within the predetermined range as in the illustrated period A. When the predetermined range is exceeded as in period B, it is determined that the vehicle is moving.

  The communication format switching process by the communication control device 12 is also in accordance with the first embodiment described above. For example, when the switching target is the number of time slots, the switching process is equivalent to the case where “PSK” and “QAM” are respectively replaced with the predetermined number of time slots in the flowchart shown in FIG.

  According to the second embodiment described above, since the movement information is created based on the reception delay time, even if the wireless communication network intentionally mixes communication with different radio field strengths, the movement status of the terminal itself Can be determined easily and appropriately.

  In TDMA communication, it is common for the base station and the mobile station to control the time slot using independent timers, and therefore it is desirable to provide a mechanism for maintaining a higher synchronization accuracy between the two. To that end, for example, a mechanism for correcting the timer (17) using the detected delay time (Δt) may be added to the mobile station.

  In the second embodiment, the frame for transmitting communication data is used in the measurement of the reception delay time (Δt). However, the present invention is not limited to this. For example, the radio base station periodically performs synchronization control. Other radio signals having a fixed communication interval with the base station, such as a transmitted beacon signal, can be used for measurement.

  FIG. 12 shows the configuration of the third embodiment of the present invention. The mobile communication terminal 103 of the present embodiment is equivalent to a combination of the configurations of the first and second embodiments described above. That is, as shown in FIG. 12, as the movement information generation unit 100B, the frequency detection device 21, the frequency deviation detection device 22, and the frequency variation observation device 23 in FIG. 2, and the delay time measurement device 24 and the delay variation observation device in FIG. 25. The reception circuit 14 includes a synchronization detection unit 16, and the communication control device 12 includes a timer 17.

  The movement information generation unit 100B of the present embodiment creates frequency fluctuation data and delay fluctuation data as movement information. At this time, the received radio wave to be measured for frequency deviation (Δf) may be received within the time slot to be measured for the other delay time (Δt). The procedure for creating the frequency variation data and the delay variation data is the same as in the above-described embodiment, and a description thereof will be omitted.

  With reference to the flowchart shown in FIG. 13, the determination process of the communication control apparatus 12 regarding a movement of a terminal is demonstrated. When the communication control device 12 recognizes the frequency variation data and the delay variation data as the movement information (S31), it determines whether or not the frequency variation data indicates that the terminal is moving.

  As a result of the determination, if the frequency variation data indicates that the terminal is moving (S32: Yes), the communication control device 12 next performs the same determination on the delay variation data. As a result, if the delay variation data also indicates that the terminal is moving (S33: Yes), it is finally determined that the terminal is moving (S34).

  On the other hand, when the frequency fluctuation data does not indicate that the terminal is moving (S32: No), and when the frequency fluctuation data indicates that the terminal is moving but the delay fluctuation data is not (S33: No), the communication control device 12 determines that the terminal is not moving (S35).

  In the above-described procedure, the frequency variation data is determined first. Instead, the other delay variation data may be determined first. In other words, the procedures “S32” and “S33” shown in FIG.

  Further, instead of the determination in the logical sum (AND) format as in the above procedure, the final determination may be performed based on the similarity of the fluctuation amount represented by both data. As the method, for example, the fluctuation amount of the frequency fluctuation data and the delay fluctuation data is standardized between the two and compared, and when the similarity satisfies a predetermined criterion, it is determined that the terminal is moving. Is. At this time, the similarity may be evaluated by a statistical method.

  As described above, the mobile communication terminal 103 according to the present embodiment determines whether or not the terminal is moving by using both the frequency deviation (Δf) and the reception delay time (Δt). This determination is advantageous in the following usage situation.

  Regarding frequency fluctuations, for example, it is assumed that noise due to other communication radio waves is generated when used while not moving, thereby disturbing the reception frequency, but there is no communication delay. In this case, according to the above determination of the present embodiment, the disturbance can be regarded not as a result of movement of the terminal but as a result of external noise. Further, for example, when a communication delay due to a high load state of the radio base station occurs, if there is no disturbance in the frequency, it can be determined that the reception delay at that time is not due to the movement of the terminal.

  Therefore, according to the third embodiment, it is possible to make a determination corresponding to the actual situation regarding the movement situation of the mobile communication terminal 103. Thereby, the reliability of determination is further enhanced.

  The movement information generation unit 100B and the communication control device 12 in the embodiment described above are not limited to hardware devices, and may be configured by a computer-readable program.

It is a block diagram which shows the basic composition of embodiment of this invention. It is a block diagram which shows the structure of the 1st Embodiment of this invention. It is a flowchart of the movement information generation part in 1st Embodiment. It is explanatory drawing for demonstrating the frequency deviation in 1st Embodiment. It is explanatory drawing of the frequency fluctuation data in 1st Embodiment. It is a flowchart of the communication control apparatus in 1st Embodiment. It is a block diagram which shows the structure of the 2nd Embodiment of this invention. It is a flowchart of the movement information generation part in 2nd Embodiment. It is explanatory drawing for demonstrating the reception delay time in 2nd Embodiment. It is explanatory drawing for demonstrating the reception delay time in 2nd Embodiment. It is explanatory drawing of the delay fluctuation data in 2nd Embodiment. It is a block diagram which shows the structure of the 3rd Embodiment of this invention. It is a flowchart of the communication control apparatus in 3rd Embodiment.

Explanation of symbols

100, 101, 102, 103 Mobile communication terminal
100A transceiver
100B movement information generator
11: Communication device, 12: Communication control device, 13: Transmission circuit, 14: Reception circuit, 15: Antenna, 16: Synchronization detector, 17: Timer
21: Frequency detector, 22: Frequency deviation detector, 23: Frequency fluctuation observation device, 24: Delay time measurement device, 25: Delay fluctuation observation device

Claims (14)

A movement information generation unit that generates movement information representing the communication status of the terminal, and a transmission / reception unit that transmits and receives a radio signal to and from a radio base station in a communication format based on the movement information,
The movement information generation unit records a history of a difference between a frequency of a radio signal received from the radio base station and a specified frequency, obtains a variation amount represented by the history as the movement information, a specified reception start timing And a means for recording the difference history between the reception timing from the radio base station and obtaining the amount of variation represented by the history as movement information ,
The transceiver unit, mobile communications terminal further comprising a means for switching the communication mode according to the result of determination by the determination of the movement status of the terminal based on the movement information. The transmitting / receiving unit determines whether or not each of the fluctuation amounts as movement information indicates movement of the own terminal, and recognizes that the own terminal is not moving when at least one of the determination results is negative. The mobile communication terminal according to claim 1 . The movement information generation unit, the mobile communication terminal according to claim 1, wherein the determination by the synchronization control information of the radio signal received reception timing from the radio base station from the radio base station. The movement information generation unit, the mobile communication terminal according to any one of claims 1 to 3, wherein the determination by the beacon signal reception timing from the radio base station. A movement information generation unit that generates movement information representing the communication status of the terminal itself, and a transmission / reception unit that transmits and receives radio signals to and from the radio base station in a communication format based on the movement information,
The movement information generation unit has means for recording a history of a difference between a prescribed reception start timing and a reception timing from a radio base station, and obtaining a variation amount represented by the history as movement information,
The transmission / reception unit includes a means for determining a movement status of the terminal based on movement information and switching a communication format according to a result of the determination. 6. The mobile communication terminal according to claim 5, wherein the movement information generation unit obtains reception timing from the radio base station based on synchronization control information of a radio signal received from the radio base station. The mobile communication terminal according to claim 5 or 6, wherein the mobile information generation unit obtains a reception timing from a radio base station from a beacon signal. A mobile communication terminal that transmits and receives radio signals to and from a radio base station in a communication format based on movement information that represents the communication status of the own terminal ,
Record the history of the difference between the frequency of the radio signal received from the radio base station and the specified frequency, obtain the amount of variation represented by the history as the movement information, the specified reception start timing and the reception timing from the radio base station, obtains the variation represented by recording a history of difference subsequent history as movement information, you characterized to switch between the communication format according to the determined said determination result movement status of the terminal based on the movement information communication control method. The mobile communication terminal determines whether or not each of the fluctuation amounts as movement information represents the movement of the own terminal, and recognizes that the own terminal is not moving when at least one of the determination results is negative. The communication control method according to claim 8, wherein: The communication control method according to claim 8 or 9 , wherein the mobile communication terminal obtains a reception timing from a radio base station from synchronization control information of a radio signal received from the radio base station. The communication control method according to any one of claims 8 to 10 , wherein the mobile communication terminal obtains a reception timing from a radio base station from a beacon signal. A mobile communication terminal that transmits and receives radio signals to and from a radio base station in a communication format based on movement information that represents the communication status of the own terminal,
The difference history between the prescribed reception start timing and the reception timing from the radio base station is recorded, the fluctuation amount represented by the history is obtained as movement information, the movement status of the terminal is determined based on the movement information, and the result of the determination A communication control method characterized in that the communication format is switched according to the method. 13. The communication control method according to claim 12 , wherein the mobile communication terminal obtains reception timing from a radio base station from synchronization control information of a radio signal received from the radio base station. The communication control method according to claim 12 or 13 , wherein the mobile communication terminal obtains a reception timing from a radio base station from a beacon signal.

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