JP2004165777A - Radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a satisfactory change in assignment of group in performing uplink and downlink communications between a base station and a plurality of communication station devices in time division with respect to a plurality of groups, by assigning a group from the plurality of groups for performing reception or transmission at the same time slot to each communication station device to be contained in the base station device, and differentiating the communication time slot between the downlink and uplink communications of each group, in a radio communication system in which the base station device contains the plurality of communication station devices and the downlink communication from the base station device to each of the communication station devices and the uplink communication from the each of the communication station devices to the base station device are performed by radio. <P>SOLUTION: The assignment of group to each of the communication station devices is changed when the communication quantity of downlink communication in a group before being changed of a communication station device whose group is to be changed is equal to or lower than an upper limit, or lower than the upper limit based on the communicable quantity of the downlink communication of the group. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wireless communication system in which a base station apparatus and a plurality of communication station apparatuses perform wireless communication, and more particularly, a group that defines a reception time zone and a transmission time zone is assigned to each communication station apparatus, and reception of each communication station apparatus is performed. The present invention relates to a technique for realizing good group assignment change in a configuration in which a time zone is different from a transmission time zone.
[0002]
[Prior art]
In recent years, a subscriber wireless access system using wireless communication called, for example, WLL (Wireless Local Loop) or FWA (Fixed Wireless Access) has been developed and put into practical use. Also, with the spread of the Internet, there is an increasing demand for high-speed, high-capacity communication over wireless media.
[0003]
In the above-described subscriber wireless access system, a base station apparatus (BSE: Base Station Equipment) connected to a backbone network such as a public line network is fixedly installed at a high place such as a building roof or a tower, and a plurality of subscribers are installed. A customer station equipment (CPE: Customer Premises Equipment) is fixedly installed at a high place such as a rooftop of a subscriber home building, and a communication terminal device such as a personal computer (PC) or such a communication terminal device is installed in the subscriber station device. A connected LAN (Local Area Network) is accommodated.
[0004]
Here, the base station device and the subscriber station device are, for example, an outdoor unit (ODU: Out Door Unit) fixedly installed at a high place such as a building roof or a tower, and an indoor unit (ODU) fixedly installed inside a building or the like. IDU: In Door Unit) with a cable. The outdoor unit of the base station device or the subscriber station device includes a wireless processing unit that performs wireless communication processing using an antenna, and mainly manages wireless communication processing. Further, the indoor unit of the base station device mainly controls data communication with the backbone network, and the indoor unit of the subscriber station device mainly controls data communication with the communication terminal device and the LAN.
[0005]
In recent years, a configuration in which a unit having the same function as an indoor unit is installed outdoors instead of such an indoor unit is also performed. In such a configuration, the unit installed outdoors and the outdoor unit are installed. Since the above-mentioned outdoor unit to be installed is connected by a cable, it is effective, for example, in a case where it is not desired to install the unit indoors.
[0006]
In the above-described subscriber wireless access system, the base station apparatus and the subscriber station apparatus are accommodated in the same base station apparatus by performing wireless communication using a communication method of performing time-division transmission using a wireless frame. Enables data communication by communicably connecting LANs connected to different subscriber station devices, and enables communication between a backbone network connected to a base station device and a LAN connected to a subscriber station device For data communication.
[0007]
Next, a configuration of a general communication frame used in P-MP (Point-Multi Point) wireless communication performed between a base station device and a plurality of subscriber station devices in the above-described subscriber wireless access system. Here is an example.
First, a configuration example of such a communication frame will be described with reference to FIG.
In the figure, communication is performed when one base station apparatus (“base station”) accommodates two subscriber station apparatuses (“subscriber station 1” and “subscriber station 2”) and performs wireless communication. An example of the procedure is shown.
[0008]
FIG. 1A shows a configuration example of a downlink communication frame used in downlink communication from the base station apparatus to the subscriber station apparatus. The downlink communication frame includes one broadcast channel (BCCH) and two broadcast channels. The unit frame composed of the downlink-only short data channel (SD1, SD2) and one downlink-only long data channel (LD1) is "first frame", "second frame", "third frame", and so on. Are arranged.
[0009]
Here, the BCCH is a downlink communication channel for synchronizing communication between the base station apparatus and the subscriber station apparatus and for granting data transmission permission from the base station apparatus to the subscriber station apparatus. And SD2 are downlink communication channels for transmitting short data from the base station device to the subscriber station device, and LD1 is a downlink communication channel for transmitting long data from the base station device to the subscriber station device.
[0010]
FIG. 2B shows a configuration example of an uplink communication frame used for uplink communication from the subscriber station apparatus to the base station apparatus. The uplink communication frame includes one request channel (LCCH) and one request channel (LCCH). A unit frame composed of two uplink-dedicated short data channels (SU1, SU2) and one uplink-dedicated long data channel (LU1) is “first frame”, “second frame”, “third frame”,. And so on.
[0011]
Here, the LCCH is an uplink communication channel for requesting data transmission from the subscriber station device to the base station device, and SU1 and SU2 are for transmitting short data from the subscriber station device to the base station device. LU1 is an uplink communication channel for transmitting long data from the subscriber station apparatus to the base station apparatus.
[0012]
Also, the downlink communication frame shown in FIG. 3A and the uplink communication frame shown in FIG. 3B are referred to as “first frame” and “upper frame” as shown in FIGS. Each of the unit frames such as "second frame", "third frame",... Is arranged in the same time zone, and in each unit frame, the BCCH and the LCCH are the same. SD1 and SU1 are arranged in the same time zone, SD1 and SU1 are arranged in the same time zone, and LD1 and LU1 are arranged in the same time zone. ing.
[0013]
When such a communication frame is used, transmission and reception are performed simultaneously in the base station device, and transmission and reception are also performed simultaneously in each subscriber station device due to the configuration of the communication frame.
Specifically, as shown in FIGS. 7A and 7B, the base station device transmits synchronization information and the like to the subscriber station device using the BCCH in each unit frame, and transmits the SD1, SD2, or LD1. To transmit data to the subscriber station device, to receive a transmission request from the subscriber station device by LCCH, and to receive data from the subscriber station device by SU1, SU2, or LU1.
[0014]
On the other hand, as shown in (c), (d), (e), and (f) of the same drawing, each subscriber station apparatus receives synchronization information and the like from the base station apparatus by BCCH in each unit frame. , SD1, SD2, and LD1, receive data from the base station, transmit a transmission request to the base station by LCCH, and transmit data to the base station by SU1, SU2, and LU1. Note that SU1, SU2, and LU1 are used by a subscriber station apparatus permitted to transmit data by the base station apparatus, and the subscriber station apparatus transmits data to the base station apparatus using these data channels.
[0015]
Referring to FIG. 12, other than the general communication frame used in the P-MP wireless communication performed between the base station apparatus and the plurality of subscriber station apparatuses in the above-described subscriber wireless access system. An example of the configuration will be described.
In the figure, an example in which one base station apparatus (“base station”) accommodates two subscriber station apparatuses (“subscriber station 1” and “subscriber station 2”) and performs wireless communication. Is shown.
[0016]
FIG. 1A shows a configuration example of a downlink communication frame used in downlink communication from the base station apparatus to the subscriber station apparatus. This downlink communication frame includes one broadcast channel (BCCH) and one broadcast channel. There are a plurality of unit frames including the downlink dedicated short data channel (SD) and one downlink dedicated long data channel (LD) such as “first frame”, “second frame”, “third frame”,. It is arranged side by side.
[0017]
FIG. 2B shows a configuration example of an uplink communication frame used for uplink communication from the subscriber station apparatus to the base station apparatus. The uplink communication frame includes one request channel (LCCH) and one request channel (LCCH). A unit frame composed of one uplink-dedicated short data channel (SU) and one uplink-dedicated long data channel (LU) is referred to as "first frame", "second frame", "third frame", and so on. Are arranged.
[0018]
Thus, the configuration of the communication frame shown in FIG. 11 is the same as that of the communication frame shown in FIG. 11 except that each unit frame includes only one short data channel (SD, SU). The configuration is the same. Even when such a communication frame is used, the base station device simultaneously performs transmission and reception as shown in FIGS. 12A and 12B due to the structure of the communication frame. As shown in FIGS. (C), (d), (e) and (f), each subscriber station device simultaneously performs transmission and reception.
[0019]
For example, Non-Patent Document 1 describes the recent situation of FWA systems (see Non-Patent Document 1).
[0020]
[Non-patent document 1]
"Wireless Broadband Textbook", edited by Takeshi Hattori and Masanobu Fujioka, IDG Japan Co., Ltd., June 10, 2002, Chapter 8, p. 301-328
[0021]
[Problems to be solved by the invention]
However, for example, in a subscriber radio access system in which a base station apparatus and a plurality of subscriber station apparatuses perform radio communication using communication frames as shown in FIG. 11 and FIG. 12, not only the base station apparatus, It is necessary to perform transmission and reception at the same time even in a subscriber station apparatus that is required to be inexpensive. For example, since a transmission / reception common unit cannot be provided in hardware, the subscriber station apparatus is expensive. And the power consumed by the subscriber station apparatus becomes large.
[0022]
Further, in the present invention, such a problem can be solved by, for example, assigning a definition regarding a group, which is an aggregate of the subscriber station devices, to the radio frame itself, so that each subscriber station device can be provided to the base station device. It is intended to propose wireless communication using a communication frame that does not allow simultaneous access to transmission and reception, but in this way, each of the plurality of subscriber station devices has one of a plurality of groups. In a subscriber wireless access system that performs wireless communication by allocating groups, it is necessary to sufficiently consider how to allocate groups.
[0023]
In other words, since the frequency of occurrence of data received by downlink communication and the data transmitted by uplink communication of each subscriber station device are different from each other and are asymmetrical, how the groups are assigned to each subscriber station device is usually determined. A difference occurs in the use status of the wireless channel in the downlink communication and the uplink communication depending on whether or not the assignment is performed, and therefore, a difference occurs in the throughput of the entire system depending on the method of assigning the groups. Further, for example, when the usage status of the wireless channel by each subscriber station device in downlink communication or uplink communication differs depending on time or the like, it is considered that it is necessary to change the group assignment at an appropriate time. However, careful consideration needs to be given to how to change group assignments.
[0024]
The present invention has been made in view of such circumstances, and a base station apparatus and a plurality of communication station apparatuses are assigned to a group by assigning a group to each communication station apparatus so that the reception time zone and the transmission time zone of each communication station apparatus are different. An object of the present invention is to provide a wireless communication system capable of realizing good group assignment change when performing wireless communication with a communication station device.
[0025]
[Means for Solving the Problems]
In order to achieve the above object, in a wireless communication system according to the present invention, a base station device accommodates a plurality of communication station devices, and performs downlink communication from the base station device to the communication station device and communication from the communication station device to the base station device. In a configuration in which uplink communication is performed wirelessly, one of a plurality of groups performing reception or transmission is assigned to each communication station device accommodated in the base station device in the same time zone, and downlink communication of each group is performed. When making the communication time zone different for uplink communication and performing each of downlink communication and uplink communication between the base station device and the plurality of communication station devices in a time-sharing manner for a plurality of groups, the group assignment to the communication station device is performed. The change is based on the fact that the communication amount of the downlink communication target in the group before the change of the communication station device related to the change (that is, the communication station device whose group assignment is changed) is based on the communicable amount of the downlink communication of the group. Below the upper limit or Performed when it is less than limit value.
[0026]
Therefore, when the communication amount of the downlink communication target is less than or equal to the upper limit value or less than the upper limit value in the group before the change of the communication station device to which the group assignment is changed, the group assignment to the communication station device is changed. In addition, it is possible to satisfactorily change the group assignment, and more specifically, it is possible to prevent the communication station device from dropping communication data when the group assignment is changed, for example.
[0027]
Further, for example, when the group assignment is changed so that the communication station device a belonging to a certain group A is replaced with the communication station device b belonging to another group B, the communication station device a before the change is changed. Is the group A, and the group before the change with respect to the communication station device b is the group B. Therefore, in the wireless communication system according to the present invention, the assignment of the groups to the two communication station devices a and b is switched. To change, the communication amount of the downlink communication target in each of the two groups A and B according to the change is equal to or less than the upper limit value or less than the upper limit value based on the communicable amount of the downlink communication of the respective groups A and B. When do.
[0028]
Also, in other cases, in the wireless communication system according to the present invention, as one configuration example, changing the assignment of the group to the communication station device may be changed to the group before the change and the group after the change of the communication station device according to the change. This is performed when the communication traffic of the downlink communication target in each of the groups is equal to or less than the upper limit based on the communicable traffic of the downlink communication in the respective group, or less than the upper limit.
[0029]
Further, in the wireless communication system according to the present invention, as one configuration example, changing the assignment of the group to the communication station device is changed such that the communication amount of the downlink communication target in the group before the change of the communication station device according to the change is the same. The communication capacity of the upstream communication target in the group before the change of the communication station device related to the change is equal to or less than the upper limit value or less than the upper limit based on the communicable amount of the downlink communication of the group, It is performed when the value is equal to or less than the upper limit value or less than the upper limit value.
[0030]
Further, for example, in a case where the same communicable amount is shared between downlink communication and uplink communication according to a communication situation, in a wireless communication system according to the present invention, as one configuration example, a group for a communication station device is used. Is changed when the communication amount of the communication target in the group before the change of the communication station device according to the change is equal to or less than the upper limit based on the communicable amount of the group. Alternatively, in the wireless communication system according to the present invention, as one configuration example, changing the assignment of the group to the communication station device is performed in each of the group before the change and the group after the change of the communication station device according to the change. This is performed when the communication volume of the communication target is equal to or less than the upper limit based on the communicable amount of each group or less than the upper limit.
[0031]
Here, the change of the group assignment to the communication station devices may be performed, for example, for each communication station device, or may be performed collectively for a plurality of communication station devices.
Further, for example, when the group assigned to the communication station device is changed from group A to group B, group A corresponds to the group before the change, and group B corresponds to the group after the change.
[0032]
Further, as the communication traffic of the downlink communication target of the group before the change or the group after the change, for example, the amount of data requested to be transmitted from the base station apparatus to the communication station apparatus to which the corresponding group is assigned The traffic is used.
In addition, as the communication traffic of the uplink communication target of the group before the change or the group after the change, for example, the amount of data requested to be transmitted from the communication station device to which the corresponding group is assigned to the base station device The traffic is used.
[0033]
As the communication amount, various types may be used. For example, not only the amount of data but also the number of times of data communication (the number of times of transmission or the number of times of reception) and a packet used for communicating data are used. Or the frequency of occurrence of data generated as a communication target may be used.
[0034]
Further, as the communicable amount of the group before the change or the communicable amount of the group after the change, for example, it is possible to perform wireless communication between the base station apparatus and the communication station apparatus to which the corresponding group is assigned. Large amounts of data are used. Also, as the communicable amount of the downlink communication, for example, the amount of data that can be communicated in the downlink communication is used, and as the communicable amount of the uplink communication, for example, it is possible to communicate in the uplink communication. Large amounts of data are used.
[0035]
The communicable amount of each group includes, for example, the size of a frequency band allocated to each group, the size of communication time allocated to each group in time-division communication, and the type of code allocated to each group in code-division communication. It is determined based on various communication conditions such as the number.
[0036]
Also, as an upper limit based on the communicable amount of the downlink communication of the group before the change or the upper limit based on the communicable amount of the downlink communication of the group after the change, for example, it is possible to perform the downlink communication in the corresponding group. The maximum communication amount is used. Specifically, for example, the maximum data communication amount that can be transmitted from the base station device to the communication station device to which the corresponding group is assigned is used. As another example of the upper limit for such downlink communication, it is also possible to use a predetermined communication amount that exceeds the maximum communication amount that can perform downlink communication in the corresponding group.
[0037]
Then, when the traffic volume of the downlink communication target in a certain group is equal to or less than the upper limit based on the communicable amount of the downlink communication of the group or less than the upper limit, for example, This is used when the communication traffic of the data being transmitted is equal to or less than the upper limit value or less than the upper limit value, that is, when there is no data to be transmitted downstream that exceeds the upper limit value.
[0038]
As a specific example, in a configuration in which data waiting to be communicated when data to be subjected to downlink communication exceeds the communicable amount of downlink communication is stored in a buffer, as an example, data is stored in the buffer. The upper limit can be set so that the group allocation is changed when the data is not stored. As another example, when the amount of data stored in the buffer is equal to or less than a predetermined threshold or less than a predetermined threshold, An upper limit can be set to change the group assignment.
[0039]
In the above description, the upper limit value for downlink communication has been described, but the same applies to the upper limit value for uplink communication, and the same applies to the upper limit value when the communicable amount is shared between downlink communication and uplink communication. is there.
[0040]
In addition, the communicable amount of downlink communication and uplink communication assigned to each group, the communicable amount of downlink communication assigned to each group, and the communicable amount of uplink communication assigned to each group are various amounts. May be used, for example, the same communicable amount may be assigned to all groups, or the same communicable amount may be assigned to some groups, Alternatively, a different communicable amount may be assigned to each group.
[0041]
Further, as the lower limit or less than the upper limit, any may be used. Specifically, a mode in which group assignment is changed when the upper limit is less than the upper limit may be used. A mode in which the group assignment is changed when the number is less than the above may be used.
Further, for example, a mode in which the group assignment is changed when one of the group before the change and the group after the change is equal to or less than the upper limit and the other is less than the upper limit may be used.
[0042]
Further, in the wireless communication system according to the present invention, as one configuration example, changing the assignment of the group to the communication station device is performed by adjusting the communication amount of each group based on the communication status of each communication station device in the past. Do it.
[0043]
Here, as the communication status of each communication station device in the past, various types may be used. For example, the communication volume of the downlink communication and the communication volume of the uplink communication of each communication station device in the past, and a combination of these may be used. It is possible to use the communication amount, the communication amount of the downlink communication, the communication amount of the uplink communication, the correspondence of the communication amount of these, and the like with respect to the past time.
[0044]
In addition, as a mode of adjusting the communication volume of each group based on the communication status of each communication station device in the past, for example, the communication status of each communication station device in the future is determined based on the communication status of each communication station device in the past. It is possible to use a mode in which prediction is performed and the traffic of each group is adjusted based on the prediction result.
[0045]
Various modes may be used as a mode of adjusting the communication volume of each group. For example, the communication amount of each group may be effectively used in downlink communication or uplink communication in each group. It is preferable to use a mode of adjusting, specifically, a mode of adjusting so as to reduce the difference in the amount of communication between the groups and an adjusting mode so as to minimize the difference of the amount of communication between the groups. And the like can be used.
[0046]
Further, as a preferable mode, a mode can be used in which groups are assigned to the respective communication station devices so as to reduce non-communication time generated in downlink communication and uplink communication of each group. As a result, wasteful non-communication time generated in wireless communication performed between the base station device and the plurality of communication station devices can be reduced, and the overall throughput of the wireless communication system can be improved.
[0047]
In addition, the non-communication time generated in the downlink communication and the uplink communication of each group is, for example, the total time of the non-communication time generated in the downlink communication and the non-communication time generated in the uplink communication. In addition, the non-communication time generated in downlink communication of each group refers to, for example, downlink communication from the base station apparatus to any communication station apparatus among the communication station apparatuses to which the same group is assigned for each group. Similarly, the non-communication time that occurs in uplink communication of each group is, for example, with respect to each group, from any communication station device among the communication station devices to which the same group is assigned. This is the time during which uplink communication to the base station device is not performed.
[0048]
In the wireless communication system according to the present invention, as one configuration example, the base station device is connected to a network, and the communicable amount of downlink communication of the network is larger than the communicable amount of downlink communication of each group. . The base station apparatus and each communication station apparatus perform asynchronous wireless communication using packets.
[0049]
Further, for example, the communicable amount of uplink communication of a network connected to the base station device is larger than the communicable amount of uplink communication of each group. Also, for example, each communication station device is connected to a network, and the communicable amount of downlink communication of each network is larger than the communicable amount of downlink communication of each group, and Is larger than the communicable amount of the uplink communication of each group.
[0050]
Here, various networks may be used as a network connected to the base station device or a network connected to each communication station device, and for example, a LAN network is used. Note that, as the network, for example, a wired network may be used, or a wireless network may be used.
[0051]
Further, when a LAN network is used, normally, compared with the communicable amount allocated to the entire downlink communication and the upstream communication, that is, compared with the total communicable amount allocated to all the groups, The communicable amount allocated to the network is much larger.
Various communications may be used as communications using packets.
Various communications may be used as the asynchronous communications.
[0052]
Hereinafter, still another configuration example of the present invention will be described.
In the present invention, as one configuration example, the base station apparatus communicates based on past communication status information storage means for storing information on communication status with each communication station apparatus in the past, and the past communication status information storage means. Group assignment changing means for changing the group assignment to the station device, and group assignment change result notifying means for notifying the communication station device of information based on the group assignment change result by the group assignment changing device by wireless communication. . Further, as one configuration example, each communication station apparatus performs group communication control for performing downlink communication and uplink communication as a group assigned to its own station apparatus (each communication station apparatus) based on information notified from the base station apparatus. Means.
[0053]
Here, various kinds of information may be used as the information regarding the communication status with each communication station device in the past.
Further, the past communication status information storage means can be configured using, for example, a memory.
[0054]
In addition, various modes may be used as a mode for changing the assignment of the group to the communication station device based on the storage content of the past communication status information storage means. For example, the group may be changed according to a predetermined rule. In such a case, the assignment can be changed.
Various timings may be used as the timing for changing the group assignment. For example, a timing at a predetermined time or a periodic timing may be used.
[0055]
Various information may be used as the information based on the group assignment change result notified to the communication station device. For example, information on the content of the group assignment may be used, or It is possible to use information of only the part that has changed in comparison with the previous group assignment result in the change result.
Further, such information may be notified to all communication station apparatuses accommodated by the base station apparatus, or may be notified only to communication station apparatuses whose group assignment has been changed. Good.
[0056]
Also, in the present invention, as one configuration example, the base station apparatus may include a communication status detection unit that detects a communication status with each communication station device, and a detection result of the communication status detection unit that is stored in the past communication status information storage unit. A past communication status information control means for reflecting the information on the past communication status.
[0057]
Here, various modes may be used as a mode of reflecting the result of detecting the communication status with each communication station device in the past information on the communication status with each communication station device (past communication status information). For example, a mode in which the past communication status information is controlled to be the latest information, a mode in which the past communication status information is controlled to be average information in the past, or the like can be used.
Various timings may be used as the timing for reflecting the result of detecting the communication status with each communication station device in the past communication status information. For example, various timings may be used. Timing or the like can be used.
[0058]
Further, in the wireless communication system according to the present invention, as one configuration example, the communication status of each base station device with each communication station device includes the amount of communication with each communication station device for each date and the day of the week with each communication station device. Communication volume for each communication station, communication volume for each weekday or holiday with each communication station device, communication volume for each time with each communication station device, communication volume set for each communication station device, and communication volume for each communication station device. One or more of the traffics related to the information service used by the station device are used. Note that two or more of these may be used in combination.
[0059]
Here, as the communication amount set for each communication station device, for example, a communication amount uniquely set for each communication station device according to a user (contractor) who uses each communication station device is used. Can be
Various information services may be used as the information service used by each communication station device. For example, services such as distribution of text information, audio information, and image information are used.
[0060]
Also, in the present invention, as one configuration example, in the base station device, the group assignment changing unit changes the group assignment to the communication station device by performing downlink communication in the group before the change of the communication station device according to the change. This is performed when the target communication amount is equal to or less than the upper limit based on the communicable amount of the downlink communication of the group or less than the upper limit.
[0061]
Also, in the present invention, as one configuration example, in the base station apparatus, the group assignment changing unit may change the group assignment to the communication station apparatus by performing the downlink communication in the group before the change of the communication station apparatus according to the change. The target communication amount is equal to or less than the upper limit based on the communicable amount of the downlink communication of the group before the change or less than the upper limit, and the communication amount of the downstream communication target in the group after the change of the communication station device related to the change is the relevant It is performed when it is equal to or less than the upper limit based on the communicable amount of downlink communication of the group after the change or less than the upper limit.
[0062]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment according to the present invention will be described with reference to the drawings.
First, by providing the radio frame itself with a definition of a group that is an aggregate of the subscriber station devices, each subscriber station device does not simultaneously access the base station device for transmission and reception. A first example and a second example will be described as examples of a wireless communication system that performs wireless communication using such a communication frame.
[0063]
First, a wireless communication system according to a first example will be described.
In the first example, in a wireless communication system in which a base station apparatus and a plurality of communication station apparatuses perform wireless communication, and in such a base station apparatus and a communication station apparatus, a reception time zone and a transmission time zone of the communication station apparatus are set to be different from each other. It aims to provide different wireless communication systems, base station devices and communication station devices, and it is expensive and high power because communication station devices used as subscriber station devices etc. perform transmission and reception simultaneously. It is intended to solve a general problem in a P-MP wireless communication system, to reduce the cost of a communication station device, and to reduce power consumption.
[0064]
Specifically, in the wireless communication system according to the first example, the base station device accommodates a plurality of communication station devices, and performs downlink communication from the base station device to the communication station device and the communication station device as follows. Uplink communication from the base station to the base station apparatus is performed wirelessly.
That is, a plurality of groups that perform reception in the same time zone and perform transmission in the same time zone (that is, perform reception or transmission in the same time zone) are provided, and each communication station device accommodated in the base station device is provided with a group. One of the groups is assigned, and the communication time zone is made different between the downlink communication and the uplink communication of each group, and each of the downlink communication and the uplink communication between the base station apparatus and the plurality of communication station apparatuses is time-divided with respect to the plurality of groups. The wireless communication is performed by the configuration described in the above.
[0065]
Therefore, a plurality of groups for performing reception (downlink communication) in the same time zone and performing transmission (uplink communication) in the same time zone are provided, and the plurality of groups are provided for each communication station apparatus accommodated in the base station apparatus. And the communication time zone is made different for the downlink communication and the uplink communication of each group, so that the reception time zone and the transmission time zone of the communication station device are different from each other. It is possible to reduce the cost of a communication station device used as a personal station device or the like and to reduce power consumption.
[0066]
Further, since each of the downlink communication and the uplink communication between the base station device and the plurality of communication station devices is performed in a time division manner with respect to the plurality of groups, for example, the base station device can continuously perform each of the downlink communication and the uplink communication. It is possible, thereby making it possible to ensure the efficiency of wireless communication.
[0067]
In this way, the communication station devices assigned to the same group perform downlink communication in the same time zone set for the group, and also perform uplink communication in the same time zone set for the group. Perform communication. Also, for example, the downlink communication time zone is different for each group and the uplink communication time zone is different for each group, and the downlink communication time zone and the uplink communication time zone are different for the same group. Is different.
[0068]
Here, the number of the plurality of communication station devices accommodated in the base station device may be various numbers, and may be fixedly set, for example, or may be changed according to communication conditions. May change. Also, the communication station device accommodated in the base station device may be fixedly set, for example, or may dynamically change according to the movement of the communication station device.
[0069]
Further, as the communication station device, for example, a fixedly installed device may be used, or a movable device may be used.
In the base station device, for example, all or some of the communication station devices in the communicable area of the base station device that require communication are authenticated as communication partners, and the authenticated communication station device is accommodated as a communication partner. Perform wireless communication.
[0070]
Further, as a mode of allocating any group to each communication station device accommodated in the base station device, for example, a mode in which a fixed allocation is performed in advance may be used, or dynamically in accordance with a communication state or the like. A mode in which the assignment is performed may be used.
Further, as the number of the plurality of groups, two or more various numbers may be used.
Further, the number of communication station devices assigned to one group is not particularly limited, and is one or more. Normally, a plurality of communication station devices are assigned to at least one group.
[0071]
Further, as a mode in which the communication time zone is different between the downlink communication and the uplink communication of each group, the downlink communication and the uplink communication between the base station device and the plurality of communication station devices are performed in a time-division manner with respect to the plurality of groups, respectively. Various embodiments may be used. In the configuration according to the first example, if the reception time zone and the transmission time zone of the communication station device are different, for example, information for synchronizing the communication station device belonging to a certain group with the base station device is used. And the like are received in another group's communication time zone.
[0072]
Further, the station device (base station device or communication station device) according to the first example performs wireless communication using the following communication frame as an example.
That is, the downlink communication frame for performing the downlink communication of each group and the uplink communication frame for performing the uplink communication of each group are arranged such that the downlink communication frame and the uplink communication frame of the same group are arranged in different time zones. Wireless communication is performed by using communication frames arranged for a plurality of groups.
[0073]
Therefore, by performing wireless communication using such a communication frame, it is possible to realize that reception and transmission by the communication station device are performed in different time zones, and thereby, similarly to the above, the conventional and In comparison, it is possible to reduce the power consumption by reducing the cost of the communication station device.
Note that various modes may be used to arrange the downlink communication frame and the uplink communication frame of the same group in different time zones.
[0074]
Next, a more detailed example of the wireless communication system according to the first example will be described.
First, an example of a wireless communication system used in the present embodiment will be described. This embodiment shows a case where the configuration according to the first example is applied to the subscriber wireless access system.
FIG. 1 illustrates a configuration example of a subscriber wireless access system as an example of a wireless communication system according to a first example.
[0075]
As shown in FIG. 1, the subscriber wireless access system according to the present embodiment includes a network management site S, a line network 3 including an ATM (Asynchronous Transfer Mode) dedicated line network, and a VLAN (Virtual LAN). ), A plurality of base station devices 11 to 14 and a plurality of subscriber station devices 21 to 26 are provided. In addition, a plurality of communication terminal devices T1 to T6 each including a personal computer or the like are connected to the subscriber station devices 21, 22, and 24 via, for example, lines C10 to C12, routers R2 to R4, and LAN lines C13 to C15. Is connected.
[0076]
The network management site S connects the terminal device 1 having, for example, an SNMP (Simple Network Monitoring Protocol) manager function to the router R1 via the line C1, and connects the telnet function unit 2 to the router R1 via the line C2. It is configured to connect with. The router R1 is connected to the circuit network 3 via the circuit C3.
[0077]
The switch unit 4 is connected to the line network 3 via a line C4, and is also connected to a plurality of base station apparatuses 11 and 12 via, for example, Ethernet (registered trademark) lines C6 and C7.
Similarly, the switch unit 5 is connected to the line network 3 via a line C5, and is also connected to a plurality of base station devices 13 and 14 via, for example, Ethernet (registered trademark) lines C8 and C9. .
[0078]
Each of the base station devices 11 to 14 has a configuration in which, for example, outdoor units A1a to A4a and indoor units A1b to A4b are connected via cables K1 to K4. Has a configuration in which, for example, outdoor units B1a to B4a and indoor units B1b to B4b are connected via cables J1 to J4. Each of the outdoor units A1a to A4a and B1a to B4a has an antenna.
[0079]
The base station devices 11 to 14 form service areas Q1 to Q4 indicated by dotted lines in FIG. 1, respectively, and communicate with the subscriber station devices 21 to 26 existing in the service areas Q1 to Q4, respectively. Housed as
Each of the subscriber station devices 21 to 26 is divided into four groups, for example, "user group A" to "user group D". Each group includes, for example, subscriber station devices 21 to 26 related to each other. ing. Also, for example, it is possible to communicatively connect only the subscriber station devices 21 to 26 belonging to each group for each group. In FIG. 1, the subscriber station devices 22 and 25 belonging to the “user group A” are connected. An example of a case where only 26 are communicably connected is shown.
[0080]
Here, control for connecting only the subscriber station devices 21 to 26 belonging to the same group in a communicable manner is performed by, for example, identifying the group identification information (group ID) of each of the subscriber station devices 21 to 26 with the base station device. It can be performed by management of 11 to 14 and the like. In the base station apparatuses 11 to 14, for example, individual identification information (individual ID) of each of the subscriber station apparatuses 21 to 26 is also managed.
[0081]
Further, in the present embodiment, for example, when a plurality of subscriber station devices are accommodated in one base station device, the plurality of subscriber station devices are divided into a plurality of groups. Wireless communication with the base station apparatus is performed using different time zones for each group, and in each group, downlink communication and uplink communication are performed in different time zones. As an example, in FIG. 1, three subscriber station devices 21 to 23 accommodated in the base station device 11 are divided into a group A and a group B, and the group A is assigned to the two subscriber station devices 22 and 23. Are assigned, and the group B is assigned to one subscriber station device 21.
[0082]
Here, various protocols may be used as a protocol when each of the base station devices 11 to 14 authenticates the subscriber station devices 21 to 26 in the service areas Q1 to Q4.
An example of such a protocol is one in which the base station device manages information on the subscriber station devices including group information, and all the subscriber station devices initially belong to a predetermined group (for example, group A). The base station apparatus starts up using the request channel (LCCH (A)) of the group to the base station apparatus, and if the started subscriber station apparatus corresponds to another group (for example, group B), the base station apparatus Uses the broadcast channel (BCCH (A)) of the predetermined group to instruct the subscriber station apparatus to shift to the other group, and shifts the subscriber station apparatus to the other group. Various configurations can be used.
[0083]
Further, as another example of the above-mentioned protocol, information of a group (for example, a group A or a group B) assigned to each subscriber station device in advance is given to each subscriber station device, and each subscriber station device is initially provided with the information. A configuration may be used in which a given group of broadcast channels (BCCHs) is searched for from each other, and authentication by the base station apparatus is established using the given group of requested channels (LCCHs).
[0084]
In the protocol as exemplified above, for example, a control frequency different from the communication frequency is separately provided, and the base station apparatus allocates a group to each subscriber station apparatus using the control frequency. Since it is not necessary to separately provide a control frequency as in the configuration to be performed, it is possible to improve the frequency use efficiency.
[0085]
In the subscriber wireless access system according to the present embodiment as described above, by performing wireless communication with the subscriber station devices 21 to 26 accommodated by the respective base station devices 11 to 14, for example, the same Connecting the subscriber station devices 21 to 23 accommodated in the base station device 11 to be communicable, or connecting the subscriber station devices 21 to 26 accommodated in different base station devices 11 to 14 to be communicable. That is, the subscriber station devices 21 to 26 are communicably connected to the line network 3 and the communication terminal devices T1 to T6 under the different subscriber station devices 21, 22, 24 are communicably connected to each other. And the communication terminal devices T1 to T6 can be communicably connected to the line network 3.
[0086]
FIG. 2 shows a configuration example of the base station apparatuses 11 to 14. In this embodiment, since the configurations and operations of the respective base station devices 11 to 14 are the same, these configurations and operations will be described together.
As shown in the figure, each of the base station apparatuses 11 to 14 includes a network connection unit 31, a transmission data processing unit 32, a radio transmission unit 33, a transmission / reception mixing unit 34, a radio reception unit 35, A data processing unit 36, a control unit 37, and an antenna 38 are provided.
[0087]
The network connection unit 31 performs data transmission by connecting to an Ethernet (registered trademark) such as 10BASE-T or 100BASE-T or an ATM dedicated line network.
The transmission data processing unit 32 converts the data input from the network connection unit 31 into a data form having a form conforming to a downstream communication frame to be transmitted to the subscribed subscriber station devices 21 to 26.
The wireless transmission section 33 performs wireless modulation processing and up-conversion processing on transmission data input from the transmission data processing section 32.
[0088]
The transmission / reception mixing unit 34 performs mixing to enable transmission of a transmission wave and reception of a reception wave at the same time, and outputs the transmission wave from the wireless transmission unit 33 to the antenna 38, and outputs the reception wave from the antenna 38 Output to the wireless receiving unit 35.
The antenna 38 transmits a transmission wave to be transmitted to a space as a radio signal, and takes in a signal transmitted by radio from the space to obtain a reception wave.
[0089]
The wireless receiving unit 35 performs a down conversion process and a wireless demodulation process on the received wave.
The reception data processing unit 36 determines and disassembles the reception data included in the received uplink communication frame, and outputs the obtained reception data to the network connection unit 31.
The control unit 37 controls various processes performed in the entire apparatus.
[0090]
FIG. 3 shows a configuration example of the subscriber station devices 21 to 26. In this embodiment, since the configurations and operations of the respective subscriber station devices 21 to 26 are the same, these configurations and operations will be described together.
As shown in the drawing, each of the subscriber station devices 21 to 26 includes a network connection unit 41, a transmission data processing unit 42, a radio transmission unit 43, a transmission / reception switch 44, a radio reception unit 45, A reception data processing unit 46, a control unit 47, and an antenna 48 are provided.
[0091]
Here, the configurations and operations of the other processing units 41 to 43 and 45 to 48 except for the transmission / reception switch 44 are, for example, those provided in the base station devices 11 to 14 shown in FIG. Same as 35 to 38.
The transmission / reception changeover switch 44 includes a path for outputting a transmission wave from the wireless transmission unit 43 to the antenna 48 and a reception wave from the antenna 48 for transmitting the transmission wave and receiving the reception wave at different timings. 45 is switched. As described above, in the present embodiment, the base station apparatuses 11 to 14 simultaneously perform transmission and reception communication, but the subscriber station apparatuses 21 to 26 perform transmission and reception at different timings without simultaneously performing transmission and reception communication.
[0092]
As described above, the communication terminal devices T1 to T6 are connected to the subscriber station devices 21 to 26 of the present example via a wired network such as Ethernet (registered trademark) or ATM, for example. The devices 21 to 26 perform transmission data processing for converting data transmitted from the respective communication terminal devices T1 to T6 into a data form in a form conforming to a communication frame to be transmitted to the base station devices 11 to 14. Then, the generated transmission data is wirelessly modulated and up-converted, and then transmitted to space as a transmission wave.
[0093]
Then, in the base station devices 11 to 14 of the present example, after receiving the transmission wave wirelessly transmitted from the accommodated subscriber station devices 21 to 26 and capturing it as a reception wave, and down-converting and radio demodulating the reception wave, Performs reception data processing for discriminating and disassembling the reception data configured on the reception frame, and performing wired data such as Ethernet (registered trademark) or ATM connected to the own station device (the base station devices 11 to 14). Transmits and outputs received data to the network.
[0094]
Further, for example, the other base station apparatuses 11 to 14 connected to the wired network and including the communication station apparatuses T1 to T6 serving as destinations of the data to be transmitted and output under the control of the base station apparatuses 11 to 11 In 14, the data transmitted and output is received via the wired network, and the data is transmitted to the subscribed subscriber station devices 21 to 26 that accommodate the communication station devices T1 to T6 that are the destinations of the data. Transmit wirelessly. Then, the subscriber station devices 21 to 26 receive the data and transmit the data to the subordinate communication station devices T1 to T6 that are the destinations of the data via the wired network.
[0095]
Next, wireless communication performed by the wireless communication system according to the first example having the configuration according to the first example will be described.
FIGS. 4A to 4D show a configuration of a communication frame used in wireless communication performed between the base station devices 11 to 14 and the subscriber station devices 21 to 26 in the wireless communication system of the present embodiment. An example is shown.
[0096]
In this example, a case is shown where the subscriber station devices 21 to 26 accommodated under one base station device 11 to 14 are divided into two groups, a group A and a group B. Hereinafter, for convenience of explanation, The base station device P accommodates the subscriber station device A and the subscriber station device B, and one subscriber station device A belongs to group A, and one subscriber station device B belongs to group B. Will be described as an example.
[0097]
Here, the group referred to in this example defines a group of subscriber station devices that perform downlink communication in the same time zone and perform uplink communication in the same time zone. In this example, each downlink communication unit frame including one broadcast channel (BCCH), two downlink dedicated short data channels (SD1 and SD2), and one downlink dedicated long data channel (LD1) is used. Each of the unit frames is exclusively used by the subscriber station apparatus belonging to the specific group assigned to the unit frame to perform downlink communication, and similarly, one request channel (LCCH) and two uplink dedicated short data channels (SU1) , SU2) and one uplink-dedicated long data channel (LU1), and each unit frame is exclusively used by a subscriber station device belonging to a specific group assigned to each unit frame. Uplink communication is performed.
[0098]
Note that the BCCH, SD1, SD2, LD1, LCCH, SU1, SU2, and LU1 shown in the present example have the same role as those described for the communication frame shown in FIG. 11, for example. Those used by Group A are indicated by adding “(A)” to the end of the name of each channel, and those used by Group B are indicated by adding “(B)” to the end of the name of each channel. Show.
Further, for example, similarly to the communication frame shown in FIG. 11, the communication frame of the present example is also one in which the base station device P performs transmission and reception at the same time. The station devices A and B perform transmission and reception in different time zones.
[0099]
In this example, in the downlink communication frame, the groups A and B are alternately assigned to each of a plurality of unit frames that are continuously arranged, that is, the base station P joins the group A in the first frame. Downlink communication to the subscriber station apparatus A is performed, downlink communication is performed from the base station apparatus P to the subscriber station apparatus B of the group B in the second frame, and subscription of the group A from the base station apparatus P is performed in the third frame. The downstream communication to the local station apparatus A is performed, and the downstream communication of the group A and the downstream communication of the group B are alternately performed, for example.
[0100]
Similarly, in this example, in the uplink communication frame, the group B and the group A are alternately assigned to each of a plurality of unit frames continuously arranged, that is, in the first frame, the subscriber station apparatus B of the group B is assigned. From the subscriber station device A in the group A to the base station device P in the second frame, and from the subscriber station device B in the group B in the third frame. , The uplink communication to the base station apparatus P is performed, and the uplink communication of the group B and the uplink communication of the group A are alternately performed, for example.
[0101]
As described above, the base station apparatus P performs communication in which transmission to group A and reception from group B are paired and communication in which transmission to group B and reception from group A are paired for each unit frame. Switch to and repeat. In synchronization with this, the subscriber station devices A in the group A perform switching between reception from the base station device P and transmission to the base station device P for each unit frame. In synchronization with this, the subscriber station apparatuses B in the B group repeatedly perform transmission to the base station apparatus P and reception from the base station apparatus P by switching for each unit frame.
[0102]
Further, as a protocol of data communication in downlink communication and uplink communication performed by each of the subscriber station devices A and B, for example, the following is used.
That is, when the subscriber station devices A and B transmit certain data to the base station device P by uplink communication, first, the subscriber station devices A and B transmit the LCCH to the base station device P. In response to the request for uplink communication, the base station apparatus P receives the request by the LCCH, and in response to the request, the data transmission channels SU1, SU2, and LU usable by the subscriber station apparatuses A and B. It is determined whether or not there is a vacancy among the subscriber stations. As a result, when it is determined that there is a vacancy, data transmission (uplink communication) is permitted to the subscriber station devices A and B by the BCCH and data to be used is determined. Notify the transmission channel. Then, in response to receiving the permission or the like by the BCCH from the base station device P, the subscriber station devices A and B perform the base station device P by uplink communication using the data transmission channel notified of the data. Send to
[0103]
When the base station device P transmits certain data to certain subscriber station devices A and B by downlink communication, first, the base station device P transmits the data to the subscriber station devices A and B by BCCH. The subscriber stations A and B notify the existence of data to be transmitted (data to be received) and the data reception channels SD1, SD2 and LD to be used. Received from the base station apparatus P using the notified data reception channel based on the content of the notification.
[0104]
As described above, in the subscriber wireless access system in which the base station apparatuses 11 to 14 and the subscriber station apparatuses 21 to 26 perform wireless communication according to the communication procedure using the communication frame having the group configuration as in the present example, The station devices 11 to 14 accommodate a plurality of subscriber station devices 21 to 26, and perform downlink communication from the base station devices 11 to 14 to the subscriber station devices 21 to 26 and the base station device 11 from the subscriber station devices 21 to 26. When wirelessly performing uplink communication to １４14, a plurality of groups A and B are provided for receiving in the same time zone and transmitting in the same time zone, and each communication accommodated in the base station apparatuses 11 to 14 is provided. One of the groups A and B is assigned to the station devices 21 to 26, and the communication time zones are different for the downlink communication and the uplink communication of each group A and B, so that the base station devices 11 to 14 and the plurality of communication station devices 21 are assigned. Of downlink and uplink communications with Performed in time division, respectively a plurality of groups A, with respect to B.
[0105]
Therefore, in the subscriber wireless access system of this example, transmission and reception do not occur at the same time in the subscriber station devices 21 to 26, so that the transmission / reception unit can be shared by hardware. Since there is no need to provide a transmission / reception mixing unit capable of performing transmission and reception at the same time, and instead of using a transmission / reception changeover switch 44, the price of the subscriber station devices 21 to 26 can be reduced. Is realized, and the power consumption can be reduced.
[0106]
Further, when operating a communication service, for example, by forming a group as in this example and allocating a radio band to each group, a specific radio band for a specific user (subscriber station apparatus) is allocated. Can be easily realized.
Also, in the communication frame of this example, when an arbitrary time zone is seen, downlink communication is always assigned to one of the groups and uplink communication is assigned to any of the other groups. Since it is ensured that the station apparatus can continuously perform the downlink communication and the uplink communication, it is possible to realize communication with less waste than the conventional communication frame as a whole communication frame. It should be noted that the mode in which communication can be performed continuously includes, of course, a mode in which a non-communication time necessary for securing normal communication is provided, such as a guard time.
[0107]
Next, wireless communication performed by the wireless communication system according to the second example having the configuration according to the first example will be described.
FIGS. 5A to 5E show a configuration of a communication frame used in wireless communication performed between the base station devices 11 to 14 and the subscriber station devices 21 to 26 in the wireless communication system of this example. An example is shown.
[0108]
In this example, a case where the subscriber station devices 21 to 26 accommodated under one base station device 11 to 14 are divided into three groups of a group A, a group B and a group C is shown. For convenience, the base station device P accommodates the subscriber station device A, the subscriber station device B, and the subscriber station device C, and one subscriber station device A belongs to group A, and one subscriber station device A belongs to group B. The case where the subscriber station apparatus B belongs and one subscriber station apparatus C belongs to the group C will be described as an example.
[0109]
Here, the configuration of the communication frame of this example is the same as the configuration of the communication frame shown in FIG. 4 except that the subscriber station devices 21 to 26 are divided into three groups. .
[0110]
That is, in this example, in the downlink communication frame, the group A, the group B, and the group C are alternately assigned to each of a plurality of unit frames that are continuously arranged. Downlink communication to the subscriber station device A of the group is performed, downlink communication from the base station device P to the subscriber station device B of the group B is performed in the second frame, and C to C in the third frame. The downlink communication to the subscriber station device C of the group is performed, and the downlink communication from the base station device P to the subscriber station device A of the group A is performed in the fourth frame. The downstream communication of the group B and the downstream communication of the group C are performed alternately.
[0111]
Similarly, in this example, in the upstream communication frame, the group C, the group A, and the group B are alternately assigned to each of a plurality of unit frames that are continuously arranged, that is, in the first frame, the subscribers of the group C are assigned. Uplink communication is performed from the station device C to the base station device P, uplink communication is performed from the subscriber station device A in the group A to the base station device P in the second frame, and subscriber B in the B group is performed in the third frame. Uplink communication is performed from the station apparatus B to the base station apparatus P, and in the fourth frame, uplink communication is performed from the subscriber station apparatus C in the C group to the base station apparatus P, and so on. And the upstream communication of the group A and the upstream communication of the group B are performed alternately.
Note that a time zone in which the subscriber station devices A to C do not transmit and receive to and from the base station device P can be treated as a time zone similar to the guard time (GT).
[0112]
As described above, in the base station apparatus P, communication in which transmission to the group A and reception from the group C are paired, communication in which transmission to the group B and reception from the group A are paired, and transmission to the group C are performed. And communication with the reception from the group B are repeated for each unit frame. Further, in synchronization with this, the subscriber station apparatus A of the group A switches between reception from the base station apparatus P, transmission to the base station apparatus P, and communication standby (pause) for each unit frame. Do. In synchronization with this, in the subscriber station apparatus B of the group B, communication standby, reception from the base station apparatus P, and transmission to the base station apparatus P are switched and repeated for each unit frame. . In synchronization with this, in the group C of subscriber stations C, transmission to the base station P, standby for communication, and reception from the base station P are switched and repeated for each unit frame. .
[0113]
As described above, even in the subscriber wireless access system in which the base station apparatuses 11 to 14 and the subscriber station apparatuses 21 to 26 perform wireless communication according to the communication procedure using the communication frame as in the present example, for example, the first The same effects as those described in the first embodiment of the configuration according to the example can be obtained.
[0114]
Next, wireless communication performed by the wireless communication system according to the third example having the configuration according to the first example will be described.
FIGS. 6A to 6F show a configuration of a communication frame used in wireless communication performed between the base station devices 11 to 14 and the subscriber station devices 21 to 26 in the wireless communication system of this example. An example is shown.
[0115]
In this example, a case is shown in which the subscriber station devices 21 to 26 accommodated under one base station device 11 to 14 are divided into four groups of a first group, a second group, a third group, and a fourth group. For convenience of explanation, the base station device P accommodates the subscriber station device A, the subscriber station device B, the subscriber station device C, and the subscriber station device D, and one group of the subscriber station devices A , One subscriber station device B belongs to the second group, one subscriber station device C belongs to the third group, and one subscriber station device D belongs to the fourth group. Will be described as an example.
[0116]
Here, the group referred to in this example defines a group of subscriber station devices that perform downlink communication in the same time zone and perform uplink communication in the same time zone.
As shown in FIG. 6A, the downlink communication frame of this example includes a broadcast channel section (BCCH section) including four broadcast channels (BCCH1 to BCCH4) and four downlink dedicated short data channels (SD1 to SD4). ) And a unit frame composed of a downlink-only long data channel unit (LD unit) including four downlink-only long data channels (LD1 to LD4). , "Second frame", "third frame",...
[0117]
Further, the BCCH section is configured by arranging BCCH1 assigned to the first group, BCCH2 assigned to the second group, BCCH3 assigned to the third group, and BCCH4 assigned to the fourth group in the stated order. I have. Similarly, the SD unit is configured by arranging SD1 assigned to the first group, SD2 assigned to the second group, SD3 assigned to the third group, and SD4 assigned to the fourth group in the stated order. ing. Similarly, the LD unit is configured such that LD1 assigned to the first group, LD2 assigned to the second group, LD3 assigned to the third group, and LD4 assigned to the fourth group are arranged in the stated order. ing.
[0118]
Also, as shown in FIG. 3B, the uplink communication frame of this example includes a request channel section (LCCH section) including four request channels (LCCH1 to LCCH4) and four uplink dedicated short data channels (SU1). To a SU4), and a unit frame including an uplink-dedicated long data channel unit (LU unit) including four uplink-dedicated long data channels (LU1 to LU4). A plurality of such as “one frame”, “second frame”, “third frame”,... Are arranged.
[0119]
Further, the LCCH section is configured by arranging LCCH3 assigned to the third group, LCCH4 assigned to the fourth group, LCCH1 assigned to the first group, and LCCH2 assigned to the second group in the stated order. I have. Similarly, the SU unit is configured such that SU3 assigned to the third group, SU4 assigned to the fourth group, SU1 assigned to the first group, and SU2 assigned to the second group are arranged in the stated order. ing. Similarly, the LU unit is configured by arranging LU3 assigned to the third group, LU4 assigned to the fourth group, LU1 assigned to the first group, and LU2 assigned to the second group in the order of description. ing.
[0120]
Also, the downlink communication frame shown in FIG. 3A and the uplink communication frame shown in FIG. 3B are referred to as “first frame” and “upper frame” as shown in FIGS. Each of the unit frames such as “second frame”, “third frame”,... Is arranged such that both unit frames are arranged in the same time zone. Also, in each unit frame, the BCCH section and the LCCH section are arranged in the same time zone, the SD section and the SU section are arranged in the same time zone, and the LD section and the LU section are the same. It is arranged in the time zone. In each of the set of the BCCH section and the LCCH section, the set of the SD section and the SU section, and the set of the LD section and the LU section, each of the four channels 1, 2, 3, and 4 for performing the downlink communication is connected to the uplink. Each of the four channels 3, 4, 1, and 2 for performing communication is arranged in the same time zone.
[0121]
Note that the BCCH, SD, LD, LCCH, SU, and LU shown in this example have the same role as those described for the communication frame shown in FIG. 12, for example, and are used by one group in this example. Those that are used are indicated by adding “1” to the end of the name of each channel, and those used by group 2 are indicated by adding “2” to the end of the name of each channel and used by group 3. Is added with “3” at the end of the name of each channel, and those used by the fourth group are added with “4” at the end of the name of each channel.
Also, for example, similarly to the communication frame shown in FIG. 12, the communication frame of the present example is one in which the base station apparatus P simultaneously performs transmission and reception, but the communication frame of the present example The station devices A to D perform transmission and reception in different time zones.
[0122]
As described above, in the subscriber wireless access system in which the base station apparatuses 11 to 14 and the subscriber station apparatuses 21 to 26 perform wireless communication according to the communication procedure using the communication frame having the group configuration as in the present example, The station devices 11 to 14 accommodate a plurality of subscriber station devices 21 to 26, and perform downlink communication from the base station devices 11 to 14 to the subscriber station devices 21 to 26 and the base station device 11 from the subscriber station devices 21 to 26. When wirelessly performing uplink communication to １４14, a plurality of groups 1 to 4 are provided for receiving in the same time zone and transmitting in the same time zone, and each communication accommodated in the base station apparatuses 11 to 14 is provided. One of the groups 1 to 4 is assigned to the station devices 21 to 26, and another group communication time zone is provided between the downlink communication time zone and the uplink communication time zone of each of the groups 1 to 4, and the base station device 11 14 to a plurality of communication station devices 21 to 26 Performed by time division each of signals and uplink communication for a plurality of groups 1-4.
[0123]
Therefore, in the subscriber wireless access system of this example, transmission and reception do not occur at the same time in the subscriber station devices 21 to 26, so that the transmission / reception unit can be shared by hardware. Since there is no need to provide a transmission / reception mixing unit capable of performing transmission and reception at the same time, and instead of using a transmission / reception changeover switch 44, the price of the subscriber station devices 21 to 26 can be reduced. Is realized, and the power consumption can be reduced.
[0124]
Further, when operating a communication service, for example, by forming a group as in this example and allocating a radio band to each group, a specific radio band for a specific user (subscriber station apparatus) is allocated. Can be easily realized.
Also, in the communication frame of this example, when an arbitrary time zone is seen, downlink communication is always assigned to one of the groups and uplink communication is assigned to any of the other groups. Since it is ensured that the down communication and the up communication can be continuously performed in the station device, it is possible to realize communication with less waste than the conventional communication frame as a whole communication frame. It should be noted that the mode in which communication can be performed continuously includes, of course, a mode in which a non-communication time necessary for securing normal communication is provided, such as a guard time.
[0125]
Further, in the subscriber wireless access system of the present example, when each of the subscriber station devices 21 to 26 switches from transmission to reception and when switching from reception to transmission, transmission and reception are not necessarily performed (pause channel). By using such a time zone as a guard time, the time zone of the guard time conventionally provided between the channel for transmission and the channel for reception can be significantly reduced. It is possible to make it shorter.
[0126]
That is, in this example, the wireless propagation delay time due to the distance between the base station devices 11 to 14 and the subscriber station devices 21 to 26 is provided before and after the transmission / reception time zone of the subscriber station devices 21 to 26. It is possible to absorb using the time slot of the idle channel. Specifically, for example, the subscriber station devices 21 to 26 far away from the base station devices 11 to 14 perform transmission related to the transmission channel in accordance with the distance from the base station devices 11 to 14 in the time zone of the transmission channel. Not only that, it is also possible to start from the time when the part of the idle channel located immediately before the transmission channel is used by using a part of the time zone. In addition, for example, the subscriber station devices 21 to 26 far from the base station devices 11 to 14 receive the reception channel in accordance with the distance to the base station devices 11 to 14 as well as the time zone of the reception channel. By using a part of the time zone of the dormant channel located immediately after the reception channel, it is possible to perform the process up to the time when the part is started.
[0127]
In the configuration in which the subscriber station devices 21 to 26 perform wireless communication using the idle channel between the transmission and reception channels in this manner, the guard time provided between the transmission channel and the reception channel should be shortened as compared with the related art. As a result, the use efficiency of the wireless band in the data communication can be improved by an amount corresponding to the shortened guard time.
[0128]
Next, a wireless communication system according to a second example will be described.
Note that this wireless communication system and the like are realized by the wireless communication system, the base station device, and the subscriber station device shown in the third embodiment of the configuration according to the first example as one embodiment.
[0129]
First, problems and objects of the configuration according to the second example will be described. In this configuration, the problem of the configuration according to the first example is also a problem.
That is, in wireless communication, a base station apparatus usually forms a communicable area (service area) of a predetermined size and performs wireless communication with a communication station apparatus existing in the communicable area. In order to absorb the delay time in wireless propagation between the communication station and the communication station, for example, depending on the distance between the base station and the communication station, the downlink communication channel to the communication station and the communication station from the communication station It is necessary to provide a guard time (GT) between the communication device and the upstream communication channel, and there is a problem that such a guard time becomes inefficient for communication.
[0130]
The guard time is inserted, for example, between a time zone in which reception is performed by the communication station device and a time zone in which transmission is performed to prevent the reception and the transmission from overlapping at the same time. That is, even when a slight delay occurs in the communication timing between the communication station device and the base station device, reception or transmission is performed by using a part of the guard time, which is a time zone in which communication is not originally performed. Thus, the overlap between the reception time zone and the transmission time zone can be prevented.
[0131]
In the configuration according to the second example, in a wireless communication system in which a base station device and a plurality of communication station devices perform wireless communication, and in such a base station device and a communication station device, the reception time zone and the transmission time of the communication station device A wireless communication system, a base station device and a communication station device in which a communication time zone of another communication station device is provided between the reception time zone and the transmission time zone by making the band different from the reception time zone; and It solves a general problem in a P-MP wireless communication system that a communication station device used as a subscriber station device and the like simultaneously performs transmission and reception and is expensive and has high power. In addition to realizing low power consumption at a low cost, the efficiency of wireless communication is improved by shortening the guard time.
[0132]
Specifically, in the wireless communication system according to the second example, the base station device accommodates a plurality of communication station devices, and performs downlink communication from the base station device to the communication station device and the communication station device as follows. Uplink communication from the base station to the base station apparatus is performed wirelessly.
That is, four or more groups that perform reception in the same time zone and perform transmission in the same time zone (that is, perform reception or transmission in the same time zone) are provided, and each communication accommodated in the base station apparatus is provided. One of the groups is allocated to the station device, and another group of communication time periods is provided between the downlink communication time period and the uplink communication time period of each group, so that the downlink communication between the base station device and the plurality of communication station devices is performed. The wireless communication is performed by a configuration in which each of the uplink communication and the uplink communication is performed in a time-division manner for a plurality of groups.
[0133]
Accordingly, four or more groups that perform reception (downlink communication) in the same time slot and transmit (uplink communication) in the same time slot are provided, and each communication station apparatus accommodated in the base station apparatus is provided with a plurality of groups. One of the plurality of groups, and the communication time zone is made different for the downlink communication and the uplink communication of each group, and the communication time of another group is set between the downlink communication time zone and the uplink communication time zone of each group. Since the time zone is provided, the reception time zone and the transmission time zone of the communication station device are provided in different time zones, and the communication time zone of another communication station device is provided between the reception time zone and the transmission time zone. By doing so, it is possible to reduce the cost of a communication station device used as, for example, a subscriber station device, reduce power consumption, and shorten the guard time to improve the efficiency of wireless communication as compared with the related art.
[0134]
Further, since each of the downlink communication and the uplink communication between the base station device and the plurality of communication station devices is performed in a time division manner with respect to the plurality of groups, for example, the base station device can continuously perform each of the downlink communication and the uplink communication. It is possible, thereby making it possible to ensure the efficiency of wireless communication.
[0135]
In this way, the communication station devices assigned to the same group perform downlink communication in the same time zone set for the group, and also perform uplink communication in the same time zone set for the group. Perform communication. Also, for example, the downlink communication time zone is different for each group and the uplink communication time zone is different for each group, and the downlink communication time zone and the uplink communication time zone are different for the same group. A different group of communication time zones is provided between the downstream communication time zone and the upstream communication time zone.
[0136]
Here, various numbers may be used as the number of the plurality of groups of four or more.
Further, the number of communication station devices assigned to one group is not particularly limited, and is one or more. Normally, a plurality of communication station devices are assigned to at least one group.
[0137]
Further, a communication time zone of another group is provided between the downlink communication time zone and the uplink communication time zone of each group, and the downlink communication and the uplink communication between the base station device and the plurality of communication station devices are respectively performed by a plurality of communication time zones. Various modes may be used as the mode for performing time division on the group. In the configuration according to the second example, if the reception time zone and the transmission time zone of the communication station device are different, for example, information for the communication station device belonging to a certain group to synchronize with the base station device is provided. And the like are received in another group's communication time zone.
[0138]
In the station device (base station device or communication station device) according to the second example, as an example, downlink communication of each group is performed using a combination of a plurality of downlink communication channels, and uplink communication of each group is performed. Is performed using a combination of a plurality of uplink communication channels, and wireless communication is performed using the following communication frame.
That is, downlink communication in which each group of downlink communication channels is arranged for a plurality of groups so that another group of communication channels is arranged between the same group of downlink communication channels and uplink communication channels. Radio communication is performed by a communication frame in which a channel section is arranged for a plurality of downlink communication channels and an uplink communication channel of each group is arranged for a plurality of groups for each uplink communication channel. I do.
[0139]
Therefore, by performing wireless communication using such a communication frame, reception and transmission by the communication station device are performed in different time zones, and another reception is performed between the reception time zone and the transmission time zone. The communication time zone of the communication station device can be provided, thereby making it possible to reduce the cost of the communication station device and reduce power consumption as compared with the related art, and to shorten the guard time to achieve wireless communication. Can be made more efficient.
Note that various modes may be used to arrange another group of communication channels between the same group of downstream communication channels and the upstream communication channel.
[0140]
Further, in the third embodiment of the configuration according to the first example described above, a case has been described in which a plurality of subscriber station devices accommodated in one base station device are divided into four groups. In the case where the communication frame is divided, the communication frame can be configured based on the same principle. As an example, when five groups are configured, for example, the base station apparatus transmits the first group, the second group, the third group, the fourth group, and the fifth group in this order in each communication channel unit, and performs the same time as this. Each subscriber station is configured to perform reception in the band in the order of the third group, the fourth group, the fifth group, the first group, the second group, or the fourth group, the fifth group, the first group, the second group, and the third group. A communication time zone of another subscriber station device can be provided between the reception time zone and the transmission time zone of the device.
[0141]
Next, a description will be given of an embodiment in which control of group assignment and the like is performed in the subscriber wireless access system as shown with reference to FIGS. Note that the communication band referred to in the present example indicates an amount that can communicate (communicable amount).
In the subscriber wireless access system of this example, one base station device (BSE) accommodates a plurality of N subscriber station devices (CPEs) and performs wireless communication. Also, the wireless communication is performed by dividing the subscriber station devices accommodated in one base station device into two or three or more groups.
[0142]
In this example, the base station device can perform wireless communication with a plurality of groups of subscriber station devices using time division communication or the like. On the other hand, each subscriber station device usually belongs to a single group, but for example, when the group to which the subscriber station device belongs is changed, it may belong to both the group before the change and the group after the change. is there.
[0143]
Further, in this example, data is wirelessly communicated between the base station apparatus and the subscriber station apparatus using communication using asynchronously flowing packets. Here, as the packet, for example, an IP (Internet Protocol) packet or the like is used.
Further, in this example, the base station device and the subscriber station device have a LAN interface, and are connected to, for example, a wired LAN to communicate data with the LAN. The communication band of the LAN interface is larger than the communication band of the wireless communication between the base station device and the subscriber station device.
[0144]
Here, temporarily, for example, the communication band in which communication can be performed for each group is fixed, the group to which each subscriber station device belongs is fixed, and the communication volume of each group belongs to the group. In a configuration that dynamically changes in accordance with the communication status of the subscriber station device, there is a problem that the utilization rate of the communication band may be biased for each group. Specifically, for example, in a certain time zone, one group has a large amount of communication exceeding the communication band, while the other group has little communication and hardly communicates. In such a case, the wireless communication band is effective as a whole even though the total communication amount of the wireless communication bands of all the groups is the total amount of data that can be transmitted. There is a problem that it cannot be used for
[0145]
Therefore, in this example, the bias of the utilization rate of the communication band for each group is eliminated by dynamically switching the subscriber station devices belonging to the group, and the efficiency of the wireless communication using the group is improved. In this example, the base station device dynamically switches the group to which the subscriber station device belongs according to the communication band of each group.
Hereinafter, such features of the present example will be described in detail.
[0146]
In the subscriber wireless access system of this example, the base station apparatus always measures the transmission / reception amount of each group and the transmission / reception amount of each subscriber station apparatus, and based on the measurement result, the utilization rate of the communication band in each group. Is dynamically changed (group switching) so that the subscriber station devices belonging to each group are equalized for a plurality of groups, thereby maximizing the available communication band as a whole. Effective use of the service. In this example, the transmission amount and the reception amount are individually measured as the measurement of the transmission / reception amount. However, for example, a mode of measuring the sum of the transmission amount and the reception amount may be used.
[0147]
Specifically, the base station apparatus of the present example is used in the past for each date and time, each day of the week, each subscriber station apparatus, or the like, for dynamically performing group switching while communication is being performed. An optimal group configuration is selected based on the traffic managed by each information service, and the group of the subscriber station devices is switched according to the selected group configuration. Further, the base station apparatus of the present example performs such group switching at a timing when the amount of downlink communication in the group to be changed does not exceed the upper limit allowed by the communication band of downlink communication in the group. Do with. Note that the group configuration referred to in the present example is a combination of the subscriber station devices allocated to each group.
[0148]
Here, as the past communication status used for estimating the optimum group configuration, various types may be used, and as described above, the following ones (1) to (3) may be used. Any one or a combination of the above can be used.
[0149]
(1) It is possible to use the communication amount for each date, the communication amount for each time or time zone, the communication amount for each day of the week, the communication amount for weekdays, and the communication amount for holidays.
Normally, a person changes his / her lifestyle between day and night, weekday and holiday, and is expected to be reflected in the communication status of the subscriber station device used by the person. As an example, it is possible to use a mode in which group switching is performed at intervals of several minutes or several hours using a calendar function provided in the base station device and data relating to the traffic measured in the past. In the calendar function, for example, date and time can be managed.
[0150]
(2) As the communication volume for each subscriber station device, a communication volume according to the attribute of the subscriber of each subscriber station device can be used.
Since the purpose of communication or the like changes for each attribute of a subscriber of the subscriber station device, it is expected that this will be reflected in the communication status of the subscriber station device used by the subscriber. As an example, a mode in which group switching is performed using data on the attribute of the subscriber of the subscriber station device and data on the communication amount measured in the past can be used. The attributes of the contractor include, for example, whether it is a corporation or an individual, the number of terminal devices connected to the subscriber station device, the age of the contractor, the sex of the contractor, and the like. Can be used.
[0151]
(3) The traffic of each information service can be used.
A subscriber station device that is set to receive a specific information service receives the information service at a predetermined time, a predetermined time zone, or the like, and this is reflected in the communication status of the subscriber station device. It is expected. As an example, group switching is performed by using data relating to a subscriber station device subscribed to various information services and data of a time at which information distribution (communication) is performed by the various information services. Embodiments can be used. As the information service, for example, various services such as a call service and a video distribution service may be used.
[0152]
Next, a specific example of group switching performed in the subscriber wireless access system of the present example will be described with reference to FIGS.
In this example, a case is shown in which two groups, a group A and a group B, are used to simplify the description.
[0153]
FIG. 7 shows an example of a group management table stored in a memory and managed by the base station apparatus in the case of a two-group configuration.
In the group management table shown in the figure, the group A includes a subscriber station device corresponding to the identification information “CPE1”, a subscriber station device corresponding to the identification information “CPE2”, and the identification information “CPE3”. , A subscriber station device corresponding to the identification information “CPE4”, a subscriber station device corresponding to the identification information “CPE5”, and a “CPE6”. It is managed that a subscriber station device or the like corresponding to the identification information "" belongs. In this example, the subscriber station device managed by the group management table matches the subscriber station device accommodated by the base station device.
[0154]
FIG. 8 shows an example of a traffic management table that stores information on past traffic by the subscriber station device, which is stored and managed in the memory by the base station device.
In the traffic management table shown in FIG. 7, communication performed between each subscriber station apparatus and the base station apparatus managed by the group management table shown in FIG. And the amount of communication performed in each time slot of the last holiday are stored.
[0155]
Here, as the last weekday, for example, a past weekday and the closest (that is, recent) weekday is used, and similarly, as the last holiday, for example, a past holiday and the most recent Close (ie recent) holidays are used. In this example, Monday to Friday are used as weekdays, and Saturday and Sunday are used as holidays.
[0156]
In this example, two hours, such as 0:00 (= 24: 00), 2:00, 4:00,..., 20:00, and 22:00. The communication traffic for each subscriber station device is stored for every other time zone. The communication amount for each time period includes, for example, an average communication amount in each time period, a sum of the communication amount in each time period, and a communication amount at a representative predetermined time in each time period. Various things may be used. Further, in this example, as the communication amount, the communication amount of the downlink communication from the base station device to the subscriber station device and the communication amount of the uplink communication from the subscriber station device to the base station device are individually managed. For example, a mode may be used in which the communication amount is calculated by combining the communication amount of downlink communication and the communication amount of uplink communication. Various units such as the number of packets and the number of bits may be used as the unit of the communication amount to be managed.
[0157]
FIG. 9 shows an example of a cycle of a process of changing the subscriber station device belonging to the group A or the group B (process of reassignment).
In the cycle shown in the figure, every day, such as 0:00 (= 24: 00), 2:00, 4:00,..., 20:00, and 22:00 As described above, it is set that the group assignment is changed every two hours.
[0158]
In the base station apparatus of this example, based on the information shown in FIG. 7 to FIG. 9, the traffic of the downlink communication and the uplink communication in all the groups (the group A and the group B in this example) is made as uniform as possible. In such a case, the optimum group configuration is determined by calculation.
Here, an example of procedures (1) to (4) of a process of determining an optimal group configuration by the base station device will be described.
[0159]
(1) First, at the timing of the group assignment change shown in FIG. 9, the total traffic of the group A and the total traffic of the group B are calculated for, for example, a two-hour period after that timing. In this example, the total traffic of the downlink communication and the total traffic of the uplink communication are individually calculated. For example, the total traffic of the total traffic of the downlink communication and the total traffic of the uplink communication is calculated. A mode of calculating may be used. This calculation is based on the information on the subscriber station devices belonging to each of the groups A and B set in the group management table before the group assignment is changed as shown in FIG. This is performed based on the information on the communication amount of each subscriber station device in the past stored in the communication amount management table.
[0160]
(2) Next, a difference between the total traffic of the group A and the total traffic of the group B calculated in the above (1) is calculated.
(3) Next, the combination of the subscriber station device belonging to the group A and the subscriber station device belonging to the group B is changed from the current combination, and the various combinations are sequentially performed in the same manner as described above. The difference between the total traffic of the group B and the total traffic of the group B is calculated.
(4) Then, after calculating the difference between the total traffic of the group A and the total traffic of the group B for all combinations or many combinations, the combination having the smallest difference is selected as the optimal group configuration. Change the group assignments to the selected combination.
[0161]
In this example, taking into account both the difference in the total amount of downlink communication and the difference in the total amount of uplink communication between the group A and the group B, for example, the size of each difference is practically An optimal group configuration that effectively reduces the size is selected. For example, an optimal group configuration that minimizes the difference in the total communication amount of the downstream communication and the upstream communication between the group A and the group B is optimal. May be used, or a group configuration that minimizes the difference in the total communication amount of either downlink communication or uplink communication between the group A and the group B is selected as the optimum one. Such an embodiment may be used.
[0162]
Specifically, an example in which the base station device changes the group assignment will be described.
FIG. 10A shows an example of the group management table before the group assignment is changed, and FIG. 10B shows an example of the group management table after the group assignment is changed. Is shown. In this example, the subscriber station apparatus corresponding to the identification information “CPE2” and the subscriber station apparatus corresponding to the identification information “CPE3”, which were allocated to the group A before the group allocation was changed, were changed by the group allocation change. A group of subscriber station apparatuses corresponding to the identification information “CPE5” and a group of the subscriber station apparatuses corresponding to the identification information “CPE6” that have been allocated to the group B and have been allocated to the group B before the change of the group assignment. Are assigned to the group A by the change in the assignment.
[0163]
As described above, in the subscriber wireless access system of the present example, the base station device holds information on the amount of communication with each subscriber station device in the past, and based on the information, determines the optimal group configuration in the future. It is guessed that group switching is performed when the amount of downlink communication in both groups before and after switching related to group switching does not exceed the upper limit based on the communication band of downlink communication of each group.
[0164]
As described above, in the subscriber wireless access system of the present example, the group switching is executed immediately when the traffic of the downlink communication in the group related to the group switching does not exceed the upper limit value, thereby immediately completing the group switching. For example, by continuously adding subscriber station devices to a certain group and increasing the number of subscriber station devices belonging to the group, or by continuously adding subscriber station devices from a certain group. This allows flexible operation such as reducing the number of subscriber station devices belonging to the group. Then, in the subscriber wireless access system of the present example, it is possible to dynamically eliminate the bias in the utilization rate of the communication band for each group, and to maximize the usable communication band.
[0165]
As another group switching method, for example, there is a method of measuring communication traffic in a short time and immediately performing group switching (hereinafter, referred to as group switching method A). For this reason, the group switching method as in this example is preferable.
That is, when group switching is performed between the base station apparatus and the subscriber station apparatus while synchronizing with each other and without losing a packet, the subscriber station apparatus before and after the group switching is used before and after the group switching. It is necessary to receive the packets of both the group and the group after the group switching. For this reason, for example, the transmission buffer of the base station device is full in one of the groups (that is, the transmission is performed). In such a case, the group switching cannot be completed until the subscriber station apparatus receives the last packet existing in the transmission buffer.
[0166]
However, even before the group switching is completed, the LAN interface of the base station device continues to receive packets from the LAN, and thus belongs to a group having a relatively large amount of downlink communication, for example. In the communication of the subscriber station device, there is a possibility that a packet may be missed.
[0167]
Specifically, for example, when the subscriber station device a belonging to the group A having a relatively large amount of downlink communication is moved to another group B, the base station is started when the group assignment change is started. Until the last packet stored in the transmission buffer of the group A in the device is received by the subscriber station device a, the packet addressed to the subscriber station device a is further stored in the transmission buffer of the group A. However, since the subscriber station device a moves to another group B, the stored packet is missed.
[0168]
Therefore, it is necessary to perform the group switching when the traffic volume of the downlink communication target in the group before and after the group switching does not exceed the upper limit based on the communication band of the downlink communication. In a user wireless access system, the communication band of the LAN interface and the communication band of wireless communication between the base station device and the subscriber station device usually have a difference of about 10 times. It is often considered that it is often difficult to immediately perform group switching following the traffic while maintaining synchronization.
For this reason, it is preferable to use the group switching method as in this example, as compared with the above-described group switching method A.
[0169]
Here, the configurations of the wireless communication system and the station device (base station device and communication station device) according to the present invention are not necessarily limited to those described above, and various configurations may be used. As an example, various numbers may be used as the number of groups to be formed, and the number of channels included in a communication frame having a group configuration and the length (time) of each channel are arbitrary. You may.
Note that the present invention can be provided, for example, as a method or a method for executing the processing according to the present invention, or a program for realizing such a method or method.
[0170]
Further, the application field of the present invention is not necessarily limited to the above-described fields, and the present invention can be applied to various fields. As an example, in this embodiment, a case has been described in which the present invention is applied to a subscriber wireless access system using a subscriber station device as a communication station device. However, the present invention is not limited to this, and the present invention is applied to various wireless communication systems. It is possible.
[0171]
Various processes such as a radio communication process performed in a radio communication system or a station device (a base station device or a communication station device) according to the present invention include, for example, a processor in a hardware resource including a processor and a memory. A configuration controlled by executing a control program stored in a ROM (Read Only Memory) may be used. For example, each functional unit for executing the processing is configured as an independent hardware circuit. You may.
Further, the present invention can be understood as a computer-readable recording medium such as a floppy (registered trademark) disk or a CD (Compact Disc) -ROM storing the above-mentioned control program or the program (the program itself). The processing according to the present invention can be performed by inputting the program from the recording medium to the computer and causing the processor to execute the program.
[0172]
【The invention's effect】
As described above, according to the wireless communication system of the present invention, the base station device accommodates a plurality of communication station devices, and performs downlink communication from the base station device to the communication station device and communication from the communication station device to the base station device. In a configuration in which uplink communication is performed wirelessly, one of a plurality of groups performing reception or transmission is assigned to each communication station device accommodated in the base station device in the same time zone, and downlink communication of each group is performed. When making the communication time zone different for uplink communication and performing each of downlink communication and uplink communication between the base station device and the plurality of communication station devices in a time-sharing manner for a plurality of groups, the group assignment to the communication station device is performed. The change is performed when the communication amount of the downlink communication target in the group before the change of the communication station device according to the change is equal to or less than the upper limit based on the communicable amount of the downlink communication of the group or less than the upper limit. Because of the group Ri against satisfactorily it can make changes, specifically, for example, can be prevented that would omission communication data in the communication station when the group assignments change.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration example of a subscriber wireless access system that is an example of a wireless communication system.
FIG. 2 is a diagram illustrating a configuration example of a base station device.
FIG. 3 is a diagram illustrating a configuration example of a subscriber station device;
FIG. 4 is a diagram illustrating a configuration example of a communication frame having a two-group configuration.
FIG. 5 is a diagram illustrating a configuration example of a communication frame having a three-group configuration.
FIG. 6 is a diagram illustrating a configuration example of a communication frame having a four-group configuration.
FIG. 7 is a diagram showing an example of a group management table in the case of a two-group configuration.
FIG. 8 is a diagram showing an example of a traffic management table.
FIG. 9 is a diagram illustrating an example of a group assignment change cycle.
FIG. 10 is a diagram illustrating an example of changing a group assignment.
FIG. 11 is a diagram illustrating a configuration example of a communication frame having no group configuration according to a conventional example.
FIG. 12 is a diagram showing another configuration example of a communication frame having no group configuration according to the conventional example.
[Explanation of symbols]
S. Network management site, 1. Terminal device,
2. Telnet function, C1-C15 line, R1-R4 router
3 ··· Network network, 4 · 5 ··· Switch unit, 11-14 ··· Base station device,
21 to 26 ... subscriber station devices,
A1a to A4a, B1a to B6a ... outdoor unit,
A1b to A4b, B1b to B6b ... indoor unit,
K1 to K4, J1 to J6, cable, T1 to T6, communication terminal device,
31, 41 network connection unit 32, 42 transmission data processing unit
33, 43 ... wireless transmission section, 34 ... transmission / reception mixing section,
35, 45 ··· Wireless reception unit, 36, 46 ··· Reception data processing unit
37, 47 ... control unit, 38, 48 ... antenna,
44 ... Transmission / reception switch

Claims (3)

In a wireless communication system in which a base station device accommodates a plurality of communication station devices and performs downlink communication from the base station device to the communication station device and uplink communication from the communication station device to the base station device wirelessly,
One of a plurality of groups performing reception or transmission in the same time zone is assigned to each communication station device accommodated in the base station device, and if the communication time zone differs between downlink communication and uplink communication of each group. The downlink communication and the uplink communication between the base station device and the plurality of communication station devices are performed in a time division manner with respect to a plurality of groups,
Changing the assignment of the group to the communication station device is performed by setting the communication amount of the downlink communication target in the group before the change of the communication station device according to the change to be equal to or less than or equal to the upper limit based on the communicable amount of the downlink communication of the group. Do when is less than,
A wireless communication system, comprising: The wireless communication system according to claim 1,
Changing the assignment of the group to the communication station device is performed based on the communication status of each communication station device in the past, by adjusting the communication amount of each group,
A wireless communication system, comprising: In the wireless communication system according to claim 1 or claim 2, the base station device is connected to a network, and a communicable amount of downlink communication of the network is larger than a communicable amount of downlink communication of each group.
The base station device and each communication station device perform asynchronous wireless communication using packets,
A wireless communication system, comprising:

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