JP2008245299A - Mobile object communication system and method for controlling signal flow-in to radio base station - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To transmit a signal without discarding the signal due to buffer overflow in a radio base station even if the transmission rate of a radio section is lower than that of a cable section. <P>SOLUTION: A control station receiving the signal to a radio mobile station from a packet network always measures the quantity of the signals to be transmitted and transmits the signals with intervals in accordance with the transmission rate of the radio section based on the measurement result. The interval of transmission is controlled so that signal quantity received from the control station in the radio base station becomes equal to that transmitted to the radio mobile station. Thus, the radio base station repeats the signals without storing or discarding them. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a mobile communication system and a method for controlling the amount of signal flow into a radio base station, and more specifically, a transmission rate between a control station and a radio base station and a transmission rate between the radio base station and the radio mobile station. The present invention relates to a mobile communication system with a different number and a method for controlling the inflow of signal to the radio base station.

  2. Description of the Related Art Conventionally, in a wireless packet service that is commercially available in Japan, a PDC packet method that shares part of network equipment with a digital cellular phone service that employs the PDC method is known.

  In this PDC packet system, a link access procedure for digital mobile channel (LAPDM) developed for mobile communication is adopted as a data link layer protocol between a network and a wireless mobile station.

  In a mobile communication system, a device that terminates LAPDM on the network side may be a radio base station or a control station that aggregates radio base stations. Considering the mobile communication-specific control that the mobile station performs channel switching control between radio base stations, it is not necessary to re-establish LAPDM even if the radio mobile station frequently switches channels. The control station is advantageous in that signal loss can be prevented, and even the current system is terminated at the control station.

  However, in the above-described configuration that has been conventionally known, the LAPDM is terminated via a wireless base station that performs wired and wireless relay. Therefore, LAPDM may be affected by signal discard in the radio base station. For example, when a large amount of signal discard occurs, retransmission control or the like occurs, and there is a problem that the transmission efficiency of LAPDM deteriorates.

  Further, signal discard in a radio base station that terminates LAPDM occurs in a situation where the wired section exceeds the transmission speed of the radio section and an excessive amount of signal flows into the radio base station. For example, if a temporary excessive inflow occurs, there is no problem because the radio base station has a function of buffering temporary signals for signal relaying, but if the state continues, the buffer amount is exceeded. There was a problem that the signal was discarded in minutes.

  By the way, as a case where the wired section exceeds the transmission speed of the wireless section, information for a plurality of wireless sections is logically multiplexed in the wired section in order to obtain a packet multiplexing effect, so the transmission capacity of the wired section for one wireless section itself. There are cases where the transmission rate of the wireless section decreases due to fluctuations in the line quality. As a countermeasure against these cases, a method of performing signal amount inflow control based on information on the signal delay and the number of retransmission control in the LAPDM layer can be considered, but the signal delay and retransmission control are excessive for the radio base station. Even in a situation where the signal amount is not flowing in, there is a problem that it may occur depending on the situation of the wireless section, and conversely, there is a possibility of performing a control that lowers the efficiency.

  The present invention has been made in view of such a problem, and the object of the present invention is to perform signal transmission from the control station to the wireless mobile station when the transmission speed of the wireless section is lower than the transmission speed of the wired section. Another object of the present invention is to provide a mobile communication system capable of performing efficient transmission without causing signal discard due to buffer overflow in the radio base station, and a signal amount inflow control method to the radio base station.

  In order to achieve such an object, the present invention provides a radio base station, a control station that receives a signal and transmits it to the radio base station, and the radio station that receives the signal. A radio mobile station that receives the signal transmitted from a radio base station, and a first transmission rate between the radio base station and the control station, and between the radio base station and the radio mobile station Mobile communication system different from the second transmission rate between the control station, the control station to the radio base station based on the measurement means for measuring the amount of the received signal and the second transmission rate And a control means for controlling the amount of the signal to be transmitted.

  Therefore, in the signal transmission from the control station to the wireless mobile station, even when the transmission speed of the wireless section is lower than the transmission speed of the wired section, it is possible to transmit without causing signal discard due to buffer overflow in the wireless base station Thus, transmission efficiency is improved.

  The invention according to claim 2 is the mobile communication system according to claim 1, wherein the control means sends the signal to the radio base station so as to be equal to an amount of the signal transmitted from the radio base station. The amount of signal transmission is controlled.

  For this reason, the radio base station can perform relaying without storing or discarding signals.

  The invention according to claim 3 is a radio base station, a control station that receives a signal and transmits the signal to the radio base station, and a radio that receives the signal transmitted from the radio base station that has received the signal. A mobile station having a first transmission rate between the radio base station and the control station and a second transmission rate different from the second transmission rate between the radio base station and the radio mobile station. In the system, the radio base station includes a measurement unit that measures the amount of the signal transmitted to the radio mobile station, and a notification unit that notifies the control station of a measurement result by the measurement unit. A station that receives the measurement result notified by the notification unit; and a control unit that controls an amount of the signal transmitted to the radio base station based on the measurement result received by the receiving unit; Having And butterflies.

  By adopting such a configuration, it is possible to prevent the control station from continuously sending out the data link layer signal exceeding the radio section transmission rate to the radio base station.

  According to a fourth aspect of the present invention, in the mobile communication system according to the third aspect, the measurement unit is based on a usage rate of a storage unit that temporarily stores the signal received from the control station. The amount of the signal transmitted to the radio mobile station is measured.

  By measuring the stored signal amount from the buffer status in this way, transmission can be performed without causing signal discard due to buffer overflow.

  The invention described in claim 5 is the mobile communication system according to claim 3 or 4, characterized in that the notifying means periodically notifies the control station of the result of the measurement.

  The invention according to claim 6 is the mobile communication system according to any one of claims 3 to 5, wherein the control means compares the measurement result with a predetermined reference value. The amount of the signal transmitted to the radio base station is controlled based on the result of the comparison.

  The invention according to claim 7 is the mobile communication system according to any one of claims 1 to 6, wherein the signal is a data link layer signal.

  The invention according to claim 8 is the mobile communication system according to any one of claims 1 to 7, wherein the amount of the signal transmitted is controlled by stopping and releasing the transmission. And

  Therefore, it is possible to prevent a decrease in transmission efficiency due to retransmission of the data link layer signal due to signal discard in the radio base station.

  The invention according to claim 9 is the mobile communication system according to any one of claims 1 to 8, wherein the control means changes the number of signals transmitted at a time to change the radio base station. The amount of the signal transmitted to the station is controlled.

  Therefore, the signal amount can be controlled not only by simply stopping the transmission of signals but also by a method of reducing the transmission amount.

  The invention according to claim 10 is the mobile communication system according to any one of claims 1 to 9, wherein the control means sends the signal to the radio base station by changing a signal size. The amount to be sent is controlled.

  The invention according to claim 11 receives a radio base station, a control station that receives a signal and transmits the signal to the radio base station, and the signal transmitted from the radio base station that has received the signal. A mobile unit comprising: a radio mobile station, wherein a first transmission rate between the radio base station and the control station is different from a second transmission rate between the radio base station and the radio mobile station A signal amount inflow control method to a radio base station in a communication system, wherein the control station measures the amount of the received signal, and the control station uses the second transmission rate based on the second transmission rate. And a control step for controlling the amount of the signal transmitted to the radio base station.

  Further, the invention according to claim 12 is the signal amount inflow control method according to claim 11, wherein the control step is performed to the radio base station so as to be equal to an amount of the signal transmitted from the radio base station. The amount of the signal transmitted is controlled.

  The invention according to claim 13 is a radio base station, a control station that receives a signal and transmits it to the radio base station, and a radio that receives the signal transmitted from the radio base station that has received the signal. A mobile station having a first transmission rate between the radio base station and the control station and a second transmission rate different from the second transmission rate between the radio base station and the radio mobile station. A signal amount inflow control method to a radio base station in a system, wherein the radio base station measures the amount of the signal transmitted to the radio mobile station, and the radio base station A notification step of notifying the control station of the measurement result, a reception step of receiving the measurement result notified by the notification step at the control station, and a reception of the measurement result of the control station. Based on the measurement result received by the step, characterized in that a control step of controlling the amount of sending the signal to the radio base station.

  The invention according to claim 14 is the signal amount inflow control method according to claim 13, wherein the measuring step is based on a usage rate of a storing step for temporarily storing the signal received from the control station. And measuring the amount of the signal transmitted to the wireless mobile station.

  The invention described in claim 15 is the signal amount inflow control method according to claim 13 or 14, wherein the notifying step periodically notifies the control station of the measurement result. .

  The signal amount inflow control method according to any one of claims 13 to 15 is characterized in that the control step compares the measurement result with a predetermined reference value. The amount of the signal transmitted to the radio base station is controlled based on the comparison result.

  The invention according to claim 17 is the signal amount inflow control method according to any one of claims 11 to 16, wherein the signal is a data link layer signal.

  The invention according to claim 18 is the signal amount inflow control method according to any one of claims 11 to 17, wherein the amount of the signal transmitted is controlled by stopping and releasing the transmission. Features.

  The invention according to claim 19 is the signal amount inflow control method according to any one of claims 11 to 18, wherein the control step changes the number of signals transmitted at a time to change the radio frequency. The amount of the signal transmitted to the base station is controlled.

  Furthermore, the invention according to claim 20 is the signal amount inflow control method according to any one of claims 11 to 19, wherein the control step changes the signal size to the radio base station. It is characterized by controlling the amount of sending.

  Therefore, according to the present invention, in signal transmission from a control station to a radio mobile station, either the radio base station or the control station measures the amount of signal transmitted to the radio mobile station, and the control station uses the signal quantity measurement result. The point of controlling the signal transmission amount in the data link layer is different from the prior art.

  According to the present invention, there is provided a radio base station, a control station that receives a signal and transmits the signal to the radio base station, and a radio mobile station that receives a signal transmitted from the radio base station that has received the signal. A mobile communication system in which a first transmission rate between a base station and a control station is different from a second transmission rate between a radio base station and a radio mobile station, the control station receiving a received signal In the signal transmission from the control station to the radio mobile station, the measurement means for measuring the amount of the signal and the control means for controlling the amount of the signal transmitted to the radio base station based on the second transmission rate. Even when the transmission speed of the section is lower than the transmission speed of the wired section, transmission can be performed without causing signal discard due to buffer overflow in the radio base station.

  Specific embodiments of the present invention will be described below.

(First embodiment)
FIG. 1 is a diagram showing a configuration of a packet mobile communication system according to an embodiment of the present invention. In FIG. 1, a control station 101 performs packet communication with a radio mobile station, and a radio base station 102 relays packet signals between the mobile device and the control station. The radio zone 103 covers the radio base station 101, and the radio mobile station 104 is located in the radio zone 103. The wireless transmission path 105 is used for transmission between the wireless mobile station 104 and the wireless base station 102, and the wired transmission path 106 is used for transmission between the wireless base station 102 and the control station 101. Here, the wired transmission path logically multiplexes information for a plurality of wireless transmission paths in order to obtain a packet multiplexing effect. Therefore, the transmission capacity of the wired transmission path is larger than the transmission capacity for one wireless section.

  FIG. 2 is a diagram showing an example of a protocol stack in the packet mobile communication system shown in FIG. The protocol stack 201 of the radio mobile station includes a physical layer facing the radio base station and a data link layer facing the control station. The protocol stack 202 of the radio base station includes a physical layer facing the radio mobile station, a physical layer facing the control station, and a sublayer facing the control station.

  The protocol stack 203 of the control station includes a physical layer facing the radio base station, a sublayer facing the radio base station, a data link layer facing the radio mobile station, and further includes a layer on the packet network side. Here, the above-described sublayer is a layer that transmits and receives additional information such as remote monitoring control information between the radio base station and the control station.

  FIG. 3 is a diagram illustrating an example of a configuration of the radio base station illustrated in FIG. The wired physical layer processing unit 301 communicates with the control station, the sublayer processing unit 302 transmits and receives additional information with the control station, and the signal processing unit 303 performs signal relay processing between the wireless mobile station and the control station. The radio physical layer processing unit 304 communicates with the radio mobile station. As shown in the example of FIG. 3, the radio base station has a plurality of radio physical layers.

  FIG. 4 is a diagram showing an example of the configuration of the control station shown in FIG. The wired physical layer processing unit 401 communicates with the wireless base station, the sublayer processing unit 402 transmits and receives additional information to and from the wireless base station, and the data link layer processing unit 403 communicates with the wireless mobile station. The signal amount measuring unit 404 measures the signal transmission amount in the data link layer determined by the number of bytes of the signal and the number of signals transmitted at a time. The signal processing unit 405 performs signal relay processing between the wireless mobile station and the packet network, and the packet network layer processing unit 406 communicates with the packet network.

  FIG. 5 is a diagram illustrating an example of a flow of signal amount inflow control from the control station to the wireless mobile station. However, signals unnecessary for explanation are omitted. Hereinafter, an example of the signal amount control method in the present invention will be described with reference to FIG.

  The control station receives signals addressed to 10 radio mobile stations from the packet network in terms of data link layer signals. This signal is indicated by a block arrow in FIG. The control station immediately starts transmitting the data link layer signal indicated by the solid line toward the radio base station, but constantly measures the amount of signal to be transmitted, and depends on the transmission rate of the radio section based on the measurement result. Send at intervals. The transmission interval is controlled so that the signal amount received from the control station in the radio base station is equal to the signal amount transmitted to the radio mobile station. Therefore, the radio base station relays the signal without storing or discarding it.

  Further, FIG. 5 shows an example in which a sublayer signal indicated by a dashed arrow is generated during transmission of a data link layer signal from the control station to the radio base station. Since the sublayer signal, which is a signal of additional information transmitted and received between the radio base station and the control station, is not related to the data link layer signal amount control, the control station immediately transmits the sublayer signal to the radio base station.

  In this series of signal control operations from the control station to the radio mobile station, the control station does not send a data link layer signal exceeding the radio section transmission rate to the radio base station. Therefore, it is possible to prevent a decrease in transmission efficiency due to retransmission of the data link layer signal due to the loss.

(Second Embodiment)
Hereinafter, other embodiments of the present invention will be described. The packet mobile communication system and protocol stack used in this embodiment are those shown in FIGS. 1 and 2, respectively.

  FIG. 6 is a diagram illustrating an example of the configuration of the radio base station illustrated in FIG. The wired physical layer processing unit 601 communicates with the control station, and the sublayer processing unit 602 transmits and receives additional information with the control station. The signal processing unit 603 performs signal relay processing between the radio mobile station and the control station, the signal amount measurement unit 604 measures the stored signal amount from the buffer status of the signal processing unit, and the radio physical layer processing unit 605 Communicate with wireless mobile stations. As shown in FIG. 6, the radio base station has a plurality of radio physical layers.

  FIG. 7 is a diagram showing an example of the configuration of the control station shown in FIG. The wired physical layer processing unit 701 communicates with the radio base station, and the sublayer processing unit 702 transmits and receives additional information to and from the radio base station. The data link layer processing unit 703 communicates with a wireless mobile station, the signal processing unit 704 performs signal relay processing between the wireless mobile station and the packet network, and the packet network layer processing unit 705 communicates with the packet network. .

  FIG. 8 is a diagram illustrating an example of a flow of signal amount inflow control from the control station to the radio mobile station. However, signals unnecessary for explanation are omitted, and numbers 801 to 807 are given to some signals for explanation. Hereinafter, the signal amount control method according to the present invention will be described with reference to FIG.

  The control station receives signals addressed to 10 radio mobile stations from the packet network in terms of data link layer signals. This signal is indicated by a block arrow. The control station immediately starts transmission of a data link layer signal 801 indicated by a solid line toward the radio base station in accordance with the transmission speed of the wired section.

  For this reason, the radio base station receives a signal at a speed exceeding the radio transmission speed, and temporarily stores a signal that cannot be transmitted in a buffer. In the radio base station, the signal amount stored in the buffer is constantly monitored, and the signal amount is compared with a specified value. When it is determined that the signal amount exceeds the specified value as a result of the comparison, the radio base station notifies the control station of information for performing transmission restriction by using the sublayer signal 802. The control station that has received the sublayer signal indicating the restriction temporarily stops transmission of the data link layer signal.

  While the transmission of the data link layer signal is restricted, the sublayer signal 803 indicated by the broken line is generated from the control station to the radio base station. However, since the sublayer signal 803 is irrelevant to the signal amount control, it is immediately transmitted. To do. If it is determined that the buffer signal amount has decreased below the specified value as a result of subsequent signal amount monitoring processing and comparison between the signal amount and the specified value in the radio base station, information for deregulation is sent to the sublayer signal. The control station is notified at 804, and the control station starts transmission of the data link layer signal 805 again.

  By the signal control method in a series of operations until the data link layer signal is retransmitted, it is possible to prevent the control station from continuing to transmit the data link layer signal exceeding the radio section transmission rate to the radio base station. Therefore, signal discard in the radio base station does not occur, and it is possible to prevent a decrease in transmission efficiency due to retransmission of the data link layer signal caused by the signal discard.

  The preferred embodiment of the present invention has been described above, but it goes without saying that the present invention is not limited to this embodiment and can be implemented in various other modes. For example, in this embodiment, the monitoring of the buffer signal amount in the radio base station and the control of the signal amount to the radio base station in the control station are composed of two stages of transmission and transmission stop. It is clear that the same effect can be obtained even if the amount is reduced below the transmission speed of the wireless section. That is, the amount of signal transmitted to the radio base station is determined by the number of bytes of the signal, that is, the signal size, and the number of signals transmitted at a time. Therefore, by changing the signal size at the control station or changing the number of signals to be transmitted, it is possible to obtain the same effect as the above-described embodiment.

  In addition, regarding a signal generated for a wireless mobile station, in a situation where a constant signal amount exceeding the wireless section transmission rate is sustained and a signal that can be classified into a plurality of signals is generated, the signal amount is Since the number of signal amount control sub-layer signals can be reduced by controlling the corresponding signal amounts in stages, it becomes more effective.

It is a figure which shows the structure of the packet mobile communication system which concerns on one Embodiment of this invention. It is a figure which shows an example of the protocol stack in a packet mobile communication system. It is a figure which shows an example of a structure of a wireless base station. It is a figure which shows an example of a structure of a control station. It is a figure which shows an example of the flow of signal amount inflow control from a control station to a radio | wireless mobile station. It is a figure which shows an example of a structure of a wireless base station. It is a figure which shows an example of a structure of a control station. It is a figure which shows an example of the flow of signal amount inflow control from a control station to a radio | wireless mobile station.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Control station 102 Wireless base station 103 Wireless zone 104 Wireless mobile station 105 Wireless transmission path 106 Wired transmission path 201 Wireless mobile station 202 Wireless base station 203 Control station 301 Wired physical layer processing part 302 Sublayer processing part 303 Signal relay part 304 Wireless physics Layer processing unit 401 Wired physical layer processing unit 402 Sublayer processing unit 403 Data link layer processing unit 404 Signal amount measurement unit 405 Signal processing unit 406 Packet network layer processing unit 601 Wired physical layer processing unit 602 Sublayer processing unit 603 Signal processing unit 604 Signal Quantity measuring unit 605 Wireless physical layer processing unit 701 Wired physical layer processing unit 702 Sublayer processing unit 703 Data link layer processing unit 704 Signal processing unit 705 Packet network layer processing unit 801 Data link layer signal 8 2 sub-layer signal (regulation)
803 Sublayer signal 804 Sublayer signal (restricted)
805 Data link layer signal 806 Sublayer signal (regulation)
807 Sublayer signal (restricted)

Claims (20)

A radio base station;
A control station for receiving a signal and transmitting to the radio base station;
A radio mobile station that receives the signal transmitted from the radio base station that has received the signal, and a first transmission rate between the radio base station and the control station, A mobile communication system different from the second transmission rate with the wireless mobile station,
The control station
Measuring means for measuring the amount of the received signal;
And a control means for controlling an amount of the signal transmitted to the radio base station based on the second transmission rate.   The mobile communication system according to claim 1, wherein the control means controls an amount of the signal transmitted to the radio base station so as to be equal to an amount of the signal transmitted from the radio base station. . A radio base station;
A control station for receiving a signal and transmitting to the radio base station;
A radio mobile station that receives the signal transmitted from the radio base station that has received the signal, and a first transmission rate between the radio base station and the control station, the radio base station, and the radio base station A mobile communication system different from the second transmission rate with the wireless mobile station,
The radio base station is
Measuring means for measuring the amount of the signal transmitted to the wireless mobile station;
Notification means for notifying the control station of the measurement result by the measurement means,
The control station
Receiving means for receiving the measurement result notified by the notifying means;
And a control means for controlling the amount of the signal transmitted to the radio base station based on the measurement result received by the receiving means.   4. The measurement unit according to claim 3, wherein the measurement unit measures the amount of the signal transmitted to the radio mobile station based on a usage rate of a storage unit that temporarily stores the signal received from the control station. The mobile communication system described.   The mobile communication system according to claim 3 or 4, wherein the notifying unit periodically notifies the control station of the measurement result.   The control means compares the measurement result with a predetermined reference value, and controls the amount of the signal transmitted to the radio base station based on the comparison result. The mobile communication system according to any one of 5.   The mobile communication system according to any one of claims 1 to 6, wherein the signal is a data link layer signal.   The mobile communication system according to any one of claims 1 to 7, wherein the control unit controls the amount of the signal to be transmitted by stopping and releasing the transmission.   The movement according to any one of claims 1 to 8, wherein the control means controls the amount of the signal transmitted to the radio base station by changing the number of signals transmitted at a time. Body communication system.   The mobile communication system according to any one of claims 1 to 9, wherein the control unit controls an amount of the signal transmitted to the radio base station by changing a signal size. A radio base station;
A control station for receiving a signal and transmitting to the radio base station;
A radio mobile station that receives the signal transmitted from the radio base station that has received the signal, and a first transmission rate between the radio base station and the control station, A signal amount inflow control method to a radio base station in a mobile communication system different from a second transmission rate with the radio mobile station,
A measurement step of measuring the amount of the received signal at the control station;
And a control step of controlling an amount of the signal transmitted to the radio base station based on the second transmission rate in the control station.   The signal amount inflow control according to claim 11, wherein the control step controls an amount of the signal transmitted to the radio base station so as to be equal to an amount of the signal transmitted from the radio base station. Method. A radio base station;
A control station for receiving a signal and transmitting to the radio base station;
A radio mobile station that receives the signal transmitted from the radio base station that has received the signal, and a first transmission rate between the radio base station and the control station, the radio base station, and the radio base station A signal amount inflow control method to a radio base station in a mobile communication system different from a second transmission rate with the radio mobile station,
In the radio base station, a measurement step of measuring the amount of the signal transmitted to the radio mobile station;
In the radio base station, a notification step of notifying the control station of the measurement result of the measurement step;
In the control station, a reception step of receiving the measurement result notified by the notification step;
And a control step of controlling an amount of the signal transmitted to the radio base station based on the measurement result received in the reception step.   14. The measurement step according to claim 13, wherein the amount of the signal transmitted to the radio mobile station is measured based on a usage rate of a storage step for temporarily storing the signal received from the control station. The signal amount inflow control method described.   The signal amount inflow control method according to claim 13 or 14, wherein the notifying step periodically notifies the control station of the measurement result.   The control step compares the measurement result with a predetermined reference value, and controls the amount of the signal transmitted to the radio base station based on the comparison result. The signal amount inflow control method according to any one of 15.   The signal amount inflow control method according to claim 11, wherein the signal is a data link layer signal.   The signal amount inflow control method according to any one of claims 11 to 17, wherein the control step controls the amount of the signal to be transmitted by stopping and releasing the transmission.   The signal according to any one of claims 11 to 18, wherein the control step controls an amount of the signal transmitted to the radio base station by changing a number of signals transmitted at a time. Volume inflow control method.   The signal amount inflow control method according to any one of claims 11 to 19, wherein the control step controls an amount of the signal transmitted to the radio base station by changing a signal size.

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