JP2010239431A - Wireless base station device, scheduling setting method for base station, and scheduling setting program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wireless base station device for reducing a load of a scheduling process in mobile radio communication, and achieving an efficient scheduling process; and the like. <P>SOLUTION: The wireless base station device 100 for executing radio communication with a plurality of mobile stations 300 includes a scheduling control part 5 including: a calculation means 5A to calculate a remaining time of a delay time allowing transmission to be waited for the mobile station 300 of a transmission destination (UE-ID) in relation to each of a plurality of divided pieces of information (packets) being transmission candidates to be input; a classification means 5B to classify the divided pieces of information into at least a plurality of one-side groups and a plurality of the other-side groups based on information related to an allowable delay time provided for the divided pieces of information (packets) on the basis of the calculated allowable remaining time; and a transmission order setting means 5C to preferentially set transmission orders to the groups of the divided pieces of information in the ascending order of the allowable remaining times out of the classified divided pieces of information. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a radio base station apparatus and the like, and particularly to a radio base station apparatus, a base station scheduling setting method, and a scheduling setting program for performing efficient packet transmission.

  In recent mobile radio communications, high speed packet access (HSPA), which is a conventional third generation (3G) mobile phone (W-CDMA) high-speed data communication, and a broadband communication system that is a further evolution of HSPA, LTE. (Long Term Evolution) etc., while providing multimedia services such as voice, video, e-mail, etc., while satisfying various requirements for transmission speed and allowable delay as transmission delay tolerance, Multimedia access with packet transmission is assumed.

  In order to perform efficient packet transmission, the radio base station apparatus monitors the transmission path state with the mobile station, and performs scheduling and allocation in order to perform resource allocation adaptively according to the reception quality of the mobile station. The technique called is used. As typical algorithms for this scheduling, a Max C / I (Maximum Carrier-to-Interference power ratio) method, a PF (Proportional Fairness) method, an RR (Round Robin) method, and the like are known.

  The Max C / I method is a method of assigning a transmission opportunity to a mobile station with the best reception quality, and can maximize the throughput, which is the amount of data transmitted within a certain time. On the other hand, mobile stations that are closer to the radio base station device have better reception quality, so there is a tendency for transmission opportunities to be assigned only to mobile stations in the vicinity of the radio base station device, and practically coverage (effective cell range). There is a problem that becomes narrow.

  The PF method is a method of assigning a transmission opportunity to a mobile station having a maximum ratio of the instantaneous value of the reception quality to the average value of the reception quality. Although the throughput is inferior to the Max C / I method, the reception quality is poor. A transmission opportunity can be allocated evenly to mobile stations located in the network.

  The RR (round robin) method is a method of equally allocating transmission opportunities to all mobile stations in a cell regardless of reception quality, and the simplest allocation control processing is sufficient, but the throughput is the Max C / I method and PF. There is a problem that it is inferior to the law.

  Furthermore, in addition to the reception quality, various factors such as the elapsed time after packet transmission and the number of retransmissions should be considered for the quality of service (QoS: Quality of Service) required by the application for the network. Therefore, a technique for performing scheduling while satisfying different service quality requirements for each packet has been proposed.

For example, in the technique “packet priority control apparatus and method” disclosed in Patent Document 1, a packet transmission delay is controlled to be less than or equal to an allowable value required by a service, and is input in order to realize a required transmission rate. Priority control is performed for packets. In this packet priority control, when the priority of a packet is determined, the priority of the packet is determined hierarchically in consideration of a plurality of priority determination factors.
By always allocating resources in consideration of a wide variety of factors in this way, priority is set according to the allowable delay for each communication, so the impact of throughput is minimized and efficiency is increased. Packet transmission is realized (see Patent Document 1).

  Further, in the technique “radio frame control apparatus, radio communication apparatus and radio frame control method” disclosed in Patent Document 2, in the downlink of OFDMA (Orthogonal Frequency Division Multiple Access) system, service quality is guaranteed, and Either OFDMA symbols or subcarriers constituting a downlink frame in order to easily construct a radio frame conforming to the IEEE (Institute of Electrical and Electronic Engineers) 802.16 (e) standard with little deterioration in frequency utilization efficiency A resource allocation unit is used so that the usage amount of one resource is constant and the usage amount of the other resource is variable.

  The transmission packets are provided with a threshold for the transmission deadline, and are arranged in order from the earliest transmission deadline. Packets waiting for transmission are grouped based on the transmission deadline, a data sequence is configured from packets transmitted using the same modulation method and the same error correction coding rate, and a resource allocation unit is set for the data sequence. While assigning, the method of resource allocation is changed for each group (see Patent Document 2).

JP 2005-86216 A JP 2008-22277 A

  Since there are usually a large number of mobile stations in the cell of the base station, if complex processing is performed for all the mobile stations in the cell, the load of scheduling processing of the base station increases. It will be. Particularly, in a broadband communication system such as LTE, since it is affected by frequency selective fading, it is common to divide the system band into small bands called a plurality of resource blocks and perform scheduling processing for each resource block. Is.

  However, as in the technique disclosed in Patent Document 1, when the priority of packets is determined hierarchically and resources are allocated in consideration of a plurality of priority determination elements, the scheduling processing load further increases. Arise. Further, as in Patent Document 2, if a resource allocation order is determined by a transmission time limit element in a high priority group and a resource allocation order is determined by a modulation index element in a low priority group, the efficiency is improved. There is a problem that the schedule processing cannot be performed.

(Object of invention)
The present invention has been made in order to solve the above-described problems of the related art, and reduces the load of scheduling processing in mobile radio communication and realizes efficient scheduling processing and base station scheduling. It is an object of the present invention to provide a method and a scheduling setting program.

  In order to achieve the above object, a radio base station apparatus according to the present invention is a radio base station apparatus that performs radio communication with a plurality of mobile stations, and a plurality of pieces of division information (packets) that are input transmission candidates. ) For calculating the remaining time of the delay time allowed to wait for transmission to the destination mobile station, and the allowable delay provided in the division information (packet) based on the calculated allowable remaining time Classifying means for classifying the divided information into at least one group and a plurality of other groups based on time-consuming information, and priority is given to the group of divided information in the shortest allowable remaining time among the classified divided information. And a scheduling control unit having a transmission order setting means for setting the transmission order.

In order to achieve the above object, a scheduling method for a base station according to the present invention is a scheduling setting method for a radio base station when performing radio communication with a plurality of mobile stations. For each of a plurality of pieces of division information (packets), an allowable remaining time of a delay time allowed to be transmitted to the destination mobile station is calculated (allowable remaining time calculating step),
Based on the allowable delay information included in the division information (packet) based on the calculated allowable remaining time, the division information is classified into at least one group and a plurality of other groups (division information classification step). The transmission order is preferentially set for the group of the division information in the shortest remaining time in the divided information (transmission order setting step).

  In order to achieve the above object, a base station scheduling setting program according to the present invention is applied to a radio base station apparatus including a scheduling control unit that functions when performing radio communication with a plurality of mobile stations. An allowable remaining time calculating function for calculating a remaining time of a delay time in which transmission waiting for a transmission destination mobile station is allowed for each of a plurality of pieces of division information (packets) that are input transmission candidates, and the calculated allowable remaining A division information classification function for classifying the division information into at least one and a plurality of other groups based on information relating to an allowable delay time included in the division information (packet) with reference to time, and the classified division information A transmission order setting function for preferentially setting transmission opportunities for the group of division information in the order of short remaining time, Characterized in that so as to be executed by a computer that grayed controller is provided.

  As described above, according to the present invention, a plurality of pieces of division information (packets) that are input transmission candidates are grouped according to the remaining time of the allowable delay time included in the division information, and transmission with less remaining time is performed. Since resource destinations are preferentially assigned to candidate groups, it is possible to effectively reduce the scheduling processing load while maintaining the required quality of service. Provides an excellent radio base station apparatus, a scheduling setting method for a base station, and a scheduling setting program that can reduce the scheduling processing load more effectively than the above-mentioned related technology. can do.

It is a block diagram which shows the structure of the radio base station apparatus in embodiment of this invention. It is explanatory drawing which shows the outline | summary of the radio | wireless communications system provided with the radio base station apparatus disclosed in FIG. FIG. 2 is a block diagram illustrating an internal configuration of a downlink packet management unit that constitutes a part of the radio base station apparatus disclosed in FIG. 1. FIG. 2 is a block diagram illustrating an internal configuration of a retransmission determination unit that constitutes a part of the radio base station apparatus disclosed in FIG. 1. FIG. 2 is a block diagram illustrating an internal configuration of a scheduling control unit that constitutes a part of the radio base station apparatus disclosed in FIG. 1. 7 is a flowchart showing an example of a selection processing operation for a packet transmission destination and service quality transmission candidate packet in the radio base station apparatus disclosed in FIG. 1; 6 is a flowchart illustrating an example of a priority evaluation value calculation processing operation in the radio base station apparatus disclosed in FIG. 1. It is a diagram which shows an example of the function which calculates the offset value added to a priority evaluation value from the remaining time in the radio base station apparatus disclosed in FIG. It is a diagram for demonstrating the calculation method of the priority evaluation value in the radio base station apparatus disclosed in FIG. 7 is a flowchart illustrating an example of an operation of scheduling processing in a scheduling control unit of the radio base station apparatus disclosed in FIG. 1.

Hereinafter, an embodiment of a radio base station apparatus, a base station scheduling setting method, and a scheduling setting program according to the present invention will be described with reference to FIG. 1 to FIG.
First, an outline of a system centering on a radio base station and a basic configuration of the radio base station according to the present invention will be described, and then specific contents of the radio base station will be described.

  FIG. 1 shows a basic configuration centering on a control unit for realizing a scheduling setting method in mobile radio communication provided in the radio base station apparatus 100 according to the present invention, and FIG. 1 shows an overview of a wireless communication system including a wireless base station device 100.

  In FIG. 2, each of the plurality of radio base station apparatuses 100 (1) to 100 (5) is division information that is divided into a predetermined amount of information in advance by performing radio communication with a plurality of mobile stations. Packet information is transmitted to the mobile station for each packet. Specifically, the radio base station apparatus 100 is connected to a network 200 such as the Internet, a public switched line, a dedicated line, etc., and is connected to the mobile station 300 (300A to 300E) in the cell 100S as its service area. By performing wireless communication, the mobile station 300 is provided with multimedia services such as voice, video, and e-mail obtained from the network 200. Further, the radio base station apparatus 100 relays multimedia services such as voice, moving image, and e-mail between the mobile stations 300 existing in the same cell 100S.

  Here, in the present embodiment, the radio base station apparatus 100 is allowed to wait for transmission to the destination mobile station for each of a plurality of pieces of division information (packets) that are input transmission candidates. And calculating means 5A for calculating the remaining time based on the information regarding the allowable delay time provided in the divided information (packet) on the basis of the calculated allowable remaining time. Classification means 5B for classifying the information into groups, and transmission order setting means 5C for preferentially setting the transmission order with respect to the group of division information in the order of the shortest allowable remaining time in the classified division information. A scheduling control unit 5 is provided.

  Therefore, according to this, a plurality of pieces of division information (packets) that are input transmission candidates are grouped according to the remaining time of the allowable delay time included in the division information, and a transmission candidate group with less remaining time is obtained. On the other hand, since the transmission destination, which is a resource, is preferentially assigned, the scheduling processing load can be effectively reduced while maintaining the required service quality.

  Further, the classification means 5B receives the priority information assigning means 32 for determining the priority of the transmission candidate by inputting the division information group having the shorter allowable delay time described above, and the allowable residual time of the delay time. An RR processing unit 33 for inputting a longer division information group and determining transmission allocation equally for the corresponding mobile stations is also provided (see FIG. 5). Further, the transmission order setting unit 5C has a priority setting function for setting transmission allocation for the division information of the priority allocation unit 32 in preference to the RR processing unit 33 described above.

  Further, the RR processing unit 33 described above has an RR processing function that gives priority to the transmission assignment of the division information to the corresponding mobile station 300 in the order from the longest elapsed time since the previous transmission assignment. For this reason, it is possible to evenly assign transmission opportunities to groups with a long remaining time.

Further, the above-described transmission order setting means 5C in the scheduling control unit 5 includes the RR processing unit in the case where more resources that can be allocated remain after the preferential resource allocation processing for the group having a short allowable remaining time until the allowable delay. An additional allocation setting function is provided for sequentially setting transmission allocation in descending order of priority for the division information on the 33 side (those positioned higher in the order of uniform transmission).
As a result, transmission opportunity allocation is performed equally and simply for groups with a long remaining time. In this respect, priority setting on the RR processing unit 33 side is simplified, and transmission allocation in the RR processing unit 33 is performed. Processing has been accelerated.

When the classification unit 5B classifies the division information into a plurality of groups based on the remaining time, the remaining time value T_rem of the delay time included in each division information calculated by the calculation unit 5A is obtained. Compared with the preset threshold T_th,
In the case of T_rem ≦ T_th, there is provided a function of allocating the plurality of pieces of division information to the priority assignment unit 32, and in the case of T_rem> T_th, the RR processing unit 33 is assigned.
As a result, the priority assigning process of a plurality of transmission candidates (division information) in the classifying means 5B can be quickly executed.

Here, when there is a plurality of transmission candidate division information for the corresponding one mobile station 300 described above, the priority assignment means 32 described above gives priority to the transmission candidate having the highest priority and its remaining time. And a function for deleting the other transmission candidates and the priority evaluation value for the remaining time, as well as sending the degree evaluation value to the transmission order setting means 5C.
As a result, it is possible to smoothly and promptly execute a countermeasure when a transmission candidate (destination of division information) competes.

Hereinafter, this will be described more specifically in relation to the overall configuration of the apparatus.
<Specific configuration of radio base station device>
FIG. 1 is a schematic block diagram showing an internal configuration of the radio base station apparatus 100 of FIG. As illustrated in FIG. 1, the radio base station apparatus 100 includes a downlink packet management unit 1, a downlink signal transmission unit 2, an uplink signal reception unit 3, a retransmission determination unit 4, and a scheduling control unit 5.

  The downlink packet management unit 1 stores a packet input from the network 200 side and outputs transmission candidate information to the scheduling control unit 5. Further, the downlink packet management unit 1 outputs a packet to be transmitted to the downlink signal transmission unit 2 according to an instruction from the scheduling control unit 5. Further, the downlink packet management unit 1 discards the stored packet according to an instruction from the retransmission determination unit 4.

  The downlink signal transmission unit 2 generates a downlink data channel based on the resource allocation information input from the scheduling control unit 5. Further, the downlink signal transmission unit 2 is a downlink control channel for notifying the mobile station 300 of information such as the destination of the downlink data channel, modulation scheme, packet data size, number of retransmissions, reception timing detection and reception quality measurement. Downlink pilot channels are generated, and downlink signals including these channels are wirelessly transmitted to the mobile station 300 in the cell 100S.

  The uplink signal receiving unit 3 receives a radio signal from the mobile station 300 in the cell 100S as an uplink signal, detects reception timing by a correlation operation with a known pilot sequence, and processes such as demodulation and decoding of the uplink control channel To obtain the downlink reception quality and ACK (acknowledgment) / NACK (rejection response) information fed back from the mobile station 300 and notify the downlink packet management unit 1 of the information.

  Based on the ACK / NACK information input from the uplink signal receiving unit 3 and the transmission information input from the scheduling control unit 5, the retransmission determination unit 4 determines whether the transmitted packet is retransmitted or does not need to be retransmitted. The determination result is notified to the downlink packet management unit 1.

  The scheduling control unit 5 performs scheduling determination using the downlink signal quality input from the uplink signal receiving unit 3 and the transmission candidate information input from the downlink packet management unit 1, and the determination result is sent to the downlink packet management unit 1. And output to the downlink signal transmission unit 2 and the retransmission determination unit 4. Here, as described above, the scheduling control unit 5 includes the calculation means 5A, the classification means 5B, and the setting means 5C.

  FIG. 3 is a block diagram showing an internal configuration of the downlink packet management unit 1 in FIG. As shown in FIG. 3, the downlink packet management unit 1 includes a selection unit 11, a plurality of packet storage units 12-1 to 12-n, and a selection unit 13.

  That is, the packet storage units 12-1 to 12-n can correspond to a plurality (maximum n) of mobile stations 300 in the cell 100S, and the destinations (UEs) of packets input from the selection unit 11 -ID), that is, the packet storage units 12-1 to 12-n store packets addressed to the mobile station 300 associated with each other by the identification code (ID) of the user equipment (UE).

  In this case, the transmitted packet includes, for example, voice information and video information that allow a certain level of error, real-time traffic that requires a certain amount of delay, and a request that requires a certain amount of delay but allows errors. There are types such as strict file transfer and non-real-time traffic such as WWW browsing, and the required quality of service (QoS) is different.

  For this reason, the packet storage units 12-1 to 12-n are provided with a buffer for each service quality, and the packet is stored in a buffer corresponding to the service quality. For example, in this embodiment, there are two types of quality of service (QoS = 1 and QoS = 2). Accordingly, each of the packet storage units 12-1 to 12-n is provided with two buffers.

  Within each buffer of the downlink packet management unit 1, there are packets that have already been transmitted and are waiting for a response to ACK / NACK information from the mobile station 300, and packets that are waiting to be transmitted. A packet that has been transmitted (waiting for a response) is processed (retransmission processing or discard processing) according to the retransmission determination result notified from the retransmission determination unit 4. When the retransmission determination result is “retransmission”, the downlink packet management unit 1 moves the packet corresponding to the retransmission to the head of the transmission waiting packet in the same buffer. On the other hand, when the retransmission determination result is “retransmission unnecessary”, the downlink packet management unit 1 discards the packet corresponding to the retransmission unnecessary.

  In the downlink packet management unit 1, the head of the packet waiting for transmission in each buffer becomes a candidate for scheduling as a transmission candidate packet, and the downlink packet management unit 1 outputs transmission candidate information to the scheduling control unit 5. The transmission candidate information includes the presence / absence of a target packet, arrival time, packet transmission destination (UE-ID), quality of service (QoS), and allowable delay.

  Based on the scheduling result from the scheduling control unit 5 in FIG. 1, the selection unit 13 acquires packets to be transmitted from the buffers of the packet storage units 12-1 to 12-n and sends them to the downlink signal transmission unit 2 in FIG. Output.

  FIG. 4 is a block diagram showing an internal configuration of the retransmission determination unit 4 in FIG. As illustrated in FIG. 4, the retransmission determination unit 4 includes a retransmission determination processing unit 21, a transmission information storage unit 22, and an allowable delay determination unit 23. A delay time is determined at the time of retransmission determination by the retransmission determination unit 4. After the radio base station apparatus 100 of FIG. 2 transmits a downlink signal to the mobile station 300, an ACK / NACK response from the mobile station 300 is transmitted. The delay time until reception is referred to as RTT (Round Trip Time).

  4, the retransmission determination processing unit 21 acquires the transmission destination (UE-ID) of the transmitted packet from the transmission information storage unit 22 before RTT (before the delay time elapses), and the uplink signal reception unit in FIG. 3 determines whether to retransmit the packet transmitted before RTT based on the ACK / NACK information from the corresponding mobile station 300 among the ACK / NACK information input from FIG. 1 to the downstream packet management unit 1.

  When ACK (acknowledgment) information is received from the corresponding mobile station 300, it indicates that the mobile station 300 has decoded the downlink signal without error, and it is no longer necessary to store the transmitted packet. Discard the used packet.

  On the other hand, when NACK (negative acknowledgment) information is received from the corresponding mobile station 300, there is an error in the downlink signal received by the mobile station 300, so it is necessary to retransmit the transmitted packet. When the unit 23 notifies that the RTT exceeds the allowable delay (allowable delay time), the retransmitted packet cannot be retransmitted. In this case, the stored transmitted packet is discarded.

  That is, the retransmission determination processing unit 21 outputs the determination result of “retransmission” to the downlink packet management unit 1 if the NACK information is received and within the allowable delay. On the other hand, the retransmission determination processing unit 21 outputs the determination result of “retransmission unnecessary” to the downlink packet management unit 1 when receiving ACK information or when receiving NACK information and exceeding the allowable delay.

  The transmission information storage unit 22 determines the transmission destination (UE-ID), quality of service (QoS), arrival time, allowable delay, and retransmission of a packet given a transmission opportunity based on the schedule determination from the scheduling control unit 5 in FIG. Information such as the number of times is acquired and stored until after the RTT at which retransmission determination is performed in the retransmission determination processing unit 21. Further, the transmission information storage unit 22 stores these pieces of information, and then outputs the transmission destination (UE-ID) of the transmission packet before RTT to the retransmission determination processing unit 21, as well as the quality of service (QoS) of the transmission packet, The arrival time, the allowable delay, and the number of retransmissions are output to the allowable delay determination unit 23.

  Based on the transmission information from the transmission information storage unit 22, the allowable delay determination unit 23 determines whether the delay time of the packet subjected to retransmission determination is within the allowable range. In this determination, the allowable delay determination unit 23 calculates a delay time based on the difference between the arrival time of the packet to be determined and the current time, and compares the calculated delay time with the allowable delay, Determine whether it is within the allowable delay.

  Then, the allowable delay determination unit 23 notifies the retransmission determination processing unit 21 of the determination result. In this case, the allowable delay determination unit 23 determines the maximum number of retransmissions in which the number of retransmissions is predetermined by the service quality (QoS). Is reached, it is handled as exceeding the allowable delay even if the delay time is within the allowable delay.

  FIG. 5 is a block diagram showing an internal configuration of the scheduling control unit 5 of FIG. 1 described above. As shown in FIG. 5, the scheduling control unit 5 includes a transmission candidate selection unit 31, a priority calculation unit 32, an RR (round robin) processing unit 33, and a scheduling determination unit 34.

  In FIG. 5, the transmission candidate selection unit 31 calculates the remaining time until the delay time allowed for transmission to the transmission destination mobile station 300 for each of a plurality of packets (division information) input in an arbitrary order. 5A is provided. Then, by this calculating means 5A, using the allowable delay included in the transmission candidate information input from the downlink packet management unit 1 of FIG. 1 and the difference between the current time and the arrival time, the remaining time until the allowable delay Calculate

  The transmission candidate selection unit 31 includes a classification unit 5B that classifies a plurality of packets (division information) into a plurality of groups (two groups in this case) based on the remaining time calculated by the calculation unit 5A. . Then, the classification unit 5B distributes information to the priority calculation unit 32 as the priority allocation unit or the RR processing unit 33 as the equal allocation unit according to the remaining time and transmits the information. Here, a group transmitted to the priority calculation unit 32 is a first (one) group, and a group transmitted to the RR processing unit 33 is a second (other) group.

  The priority calculation unit (priority allocation unit) 32 classifies the packet candidate (divided information) by the transmission candidate selection unit 31 for the remaining time calculated by the calculation unit 5A of the transmission candidate selection unit 31 that is shorter than a predetermined threshold. 1 is provided with a function of assigning priority in transmission for each packet of the first group classified by 5B, the remaining time until the allowable delay input from the transmission candidate selection unit 31, and the upstream signal reception unit 3 of FIG. Is used to calculate the priority of the transmission candidate packet for scheduling determination, and outputs the calculation result to the scheduling determination unit 34.

  The RR processing unit (equal allocation unit) 33 is a second group in which the remaining time calculated by the calculation unit 5A of the transmission candidate selection unit 31 is classified by the classification unit 5B of the transmission candidate selection unit 31 for the remaining time or more. For the corresponding mobile station 300, the transmission order (priority) of the transmission candidate packets is determined based on the RR (round robin) method, and the determined result is The data is output to the scheduling determination unit 34.

  The scheduling determination unit 34 operates as a transmission order setting unit 5C that sets a transmission schedule for each group classified by the classification unit 5B of the transmission candidate selection unit 31, and is input from the priority calculation unit (priority allocation unit) 32. The transmission opportunities are assigned to the transmission candidate packets in descending order of priority.

  Further, the transmission order setting unit 5C of the scheduling determination unit 34 has resources for which transmission opportunities can be allocated after the transmission opportunity allocation has been completed for all transmission candidate packets input from the priority calculation unit 32. If there are remaining transmission opportunities, transmission opportunities are assigned to the transmission candidate packets input from the RR processing unit 33 in the order of early transmission order (in order of priority).

Then, the scheduling determination unit 34 outputs the scheduling determination result and the transmission information related to the transmission candidate packet to which the transmission opportunity is assigned to the downlink packet management unit 1, the downlink signal transmission unit 2, and the retransmission determination unit 4 in FIG. .
Here, as the downlink signal transmission unit 2 and the uplink signal reception unit 3 shown in FIG. 1, known ones are used.

<Scheduling setting method>
Next, a scheduling setting method according to the embodiment of the present invention will be described with reference to FIGS.
First, the basic procedure content of the scheduling setting method will be described.

  First, when wireless communication is performed with a plurality of mobile stations 300, a delay time that allows waiting for transmission to the destination mobile station 300 for each of a plurality of pieces of division information (packets) that are input transmission candidates is allowed. The remaining time is calculated by the calculating means 5A (allowable remaining time calculating step).

  Next, the division means 5B classifies the division information into at least one and the other plural groups based on the allowable delay information included in the division information (packet) based on the calculated allowable remaining time (division). Information classification process). Next, the transmission order setting means 5C preferentially sets the transmission order for the above-mentioned group of division information in the shortest remaining time in the classified division information (transmission order setting step).

Here, in the division information classification (execution of the division information classification step) by the classification means 5B described above, each division information that constitutes a group of division information having a shorter allowable delay time as one transmission candidate. A priority is assigned by the priority assigning means 32 (execution of the priority assignment step), and the mobile station corresponding to the priority of each piece of divided information with the division information group having the longer allowable delay time remaining as the other transmission candidate The equal allocation means 33 determines the transmission allocation so as to equalize (execute the equal transmission allocation step).
When transmitting each piece of division information, one transmission candidate is set in preference to the other transmission candidate according to the above-described equal transmission allocation.

In addition, when transmitting each piece of division information described above, if there are more resources that can be allocated after preferential resource allocation processing for one transmission candidate with a short allowable remaining time until the allowable delay, the allowable remaining time The transmission allocation is sequentially set in the descending order of priority specified by the equal allocation means 33 for the other transmission candidate with a long.
This will be described in detail below.

  FIG. 6 is a flowchart showing the operation of the selection process for one packet transmission destination (UE-ID) and quality of service (QoS) transmission candidate packet in the transmission candidate selection unit 31 of FIG.

  First, the presence / absence of a transmission candidate packet is checked with reference to transmission candidate information input from the downlink packet management unit 1 in FIG. 1 (step S101). If there is no transmission candidate packet, the flowchart of this selection process is ended. If there is a transmission candidate packet, the remaining time until the allowable delay is calculated using the difference between the current time and the arrival time of the transmission candidate packet. (T_rem) is calculated (step S102).

  Next, in order to group the transmission candidate packets, the calculated remaining time (T_rem) is compared with a preset threshold value (T_th) (step S103). As a result of the comparison, if the remaining time (T_rem) is smaller than the threshold value (T_th) (step S103: Yes), the transmission candidate information and the remaining time (T_rem) are output to the priority calculation unit 32 (step S104). On the other hand, when the remaining time (T_rem) is equal to or greater than the threshold (T_th) (step S103: No), the transmission candidate information is output to the RR processing unit 33 (step S105).

FIG. 7 illustrates a process of calculating a priority evaluation value in the priority calculation unit 32 for a single packet transmission destination (UE-ID) and service quality (QoS) transmission candidate packet in the transmission candidate selection unit 31 in FIG. It is a flowchart which shows operation | movement.
First, the reception quality information from the mobile station 300 corresponding to the packet transmission destination (UE-ID) is acquired from the uplink signal reception unit 3 in FIG. 1 (step S201). Next, the correction value of the reception quality information is calculated using the remaining time (T_rem) input from the transmission candidate selection unit 31, and the reception quality information is corrected by the correction value (step S202).

  Next, the priority evaluation value of the transmission candidate packet is calculated (step S203). Then, it is determined whether there are a plurality of transmission candidate packets to be transmitted to the same mobile station 300 (step S204). When there are a plurality of transmission candidate packets to be transmitted to the same mobile station 300 (step S204: Yes), only the transmission candidate packets having the highest priority are left, and other transmission candidate packets and priority evaluation values The calculation result is deleted (step S205).

On the other hand, when there is one transmission candidate packet to be transmitted to the same mobile station 300 (step S204: No), or after the transmission candidate packet and the priority evaluation value calculation result are deleted in step S205, one transmission candidate packet is transmitted. The priority evaluation value calculated for the transmission candidate packet is output to the scheduling determination unit 34 (step S206). In this way, the priority calculation unit 32 (priority assignment unit) corrects the reception quality.
Further, when there are a plurality of packets to be transmitted to the same mobile station 300, the priority calculation unit 32 determines other packets except the one with the highest priority among the plurality of packets as the first packet. Remove from group.

  FIG. 8 is a diagram illustrating an example of a function for calculating an offset value (Δ_offset) to be added to the priority evaluation value from the remaining time (T_rem). As shown in FIG. 8, the offset value (Δ_offset) to be added becomes the maximum value α when the remaining time (T_rem) is zero, and decreases in inverse proportion as the remaining time (T_rem) becomes larger than zero. It is zero when (T_rem) is a threshold value (T_th). That is, the priority evaluation value increases as the remaining time (T_rem) is shorter than the threshold (T_th).

  FIG. 9 is a diagram for explaining a method of calculating the priority evaluation value. The priority evaluation value is given by a value {Q (tn) + Δ_offset} obtained by adding Δ_offset that is an offset value to Q (tn) that is an instantaneous value of reception quality at time tn. As the remaining time until the allowable delay (T_rem) is smaller, the offset value Δ_offset becomes a larger value. Therefore, the shorter the remaining time until the allowable delay is, the larger the priority evaluation value is, and it is easier to allocate resources with higher priority. Become. In this way, the priority calculation unit 32 (priority assignment means) corrects the instantaneous value of reception quality.

  On the other hand, the transmission candidate packets selected by the transmission candidate selection unit 31 in FIG. 5 and input to the RR processing unit 33 are given priority in the order of the longest elapsed time since the previous resource was allocated, The data is output to the scheduling determination unit 34. As a result, the RR processing unit 33 executes a round robin method in which a plurality of mobile stations 300 that provide services in the cell 100S of FIG.

  FIG. 10 is a flowchart showing the operation of the scheduling process in the scheduling determination unit 34 of FIG. First, the scheduling determination unit 34 allocates resource blocks from transmission candidates having the highest priority evaluation value for the transmission candidate packets input from the priority calculation unit 32 (step S301).

  Next, it is determined whether or not an allocatable resource block remains (step S302). If no assignable resource block remains (step S302; No), the scheduling process ends.

  On the other hand, if a resource block that can be allocated remains (step S302: Yes), the mobile station 300 that is the packet transmission destination to which the resource has been allocated is deleted from the transmission candidate packets input from the RR processing unit 33. (Step S303). Furthermore, resource blocks are allocated from the transmission candidate packets input from the RR processing unit 33 in the order of early transmission order (step S304).

  Here, in the embodiment described above, in particular, the operation of each component of the scheduling control unit, that is, arithmetic processing, classification processing, priority setting, and transmission order setting for a plurality of pieces of division information that are transmission candidates described above. Each processing function such as the above may be programmed and executed by a computer.

  Moreover, in the said embodiment, as shown in FIG. 1, although the case where the radio base station apparatus 100 was comprised with hardware was demonstrated, this invention is not limited to the said embodiment. An LSI processor such as a CPU (Central Processing Unit) and a non-volatile memory such as a flash ROM are provided inside the radio base station apparatus 100, and a scheduling processing program recorded in an external recording medium is read, or The scheduling processing program may be downloaded from the second network 200 or another network site and installed in the nonvolatile memory, and the scheduling processing program may be executed by the processor.

  As described above, in this embodiment, a plurality of pieces of division information (packets) that are input transmission candidates are grouped according to the remaining time of the allowable delay time included in the division information and the remaining time is set. Since resource destinations are preferentially allocated to a small number of transmission candidate groups, it is possible to effectively reduce the scheduling processing load while maintaining the required service quality, and to a group with a long remaining time. On the other hand, since the transmission opportunities are allocated equally, the superior radio base station apparatus, the base station scheduling setting method, and the scheduling setting, which are not in the related art described above, can further effectively reduce the scheduling processing load. A program can be provided.

  The present invention relates to a manufacturing industry that manufactures mobile stations such as a radio base station apparatus and a mobile phone constituting a radio system, and an information provision industry that provides a multimedia service such as voice, image, and e-mail using the radio system. It is applicable to.

DESCRIPTION OF SYMBOLS 1 Downstream packet management part 2 Downstream signal transmission part 3 Upstream signal reception part 4 Retransmission determination part 5 Scheduling control part 5A Arithmetic means 5B Classification means 5C Transmission order setting means (setting means)
DESCRIPTION OF SYMBOLS 11, 13 Sorting part 12-1, 12-2, -12-n Packet storage part 21 Retransmission determination processing part 22 Transmission information storage part 23 Permissible delay judgment part 31 Transmission candidate selection part (calculation means, classification means)
32 Priority calculation unit (priority allocation means)
33 RR processing unit (equal allocation means)
34 Scheduling determination unit (transmission order setting means)
100 radio base station apparatus 100S cell 200 network 300 mobile station

Claims (12)

A wireless base station device that performs wireless communication with a plurality of mobile stations,
Calculation means for calculating the remaining time of the delay time that is allowed to wait for transmission to the destination mobile station for each of the plurality of pieces of division information that are input transmission candidates;
Classification means for classifying the division information into at least one and the other plural groups based on information on the allowable delay time provided in the division information with reference to the calculated allowable remaining time;
Transmission order setting means for preferentially setting the transmission order for the group of division information in the order of short allowable remaining time among the classified division information,
A radio base station apparatus comprising: a scheduling control unit including: The radio base station apparatus according to claim 1,
Priority assigning means for inputting a division information group having a shorter allowable delay time to the classification means and determining the priority of transmission candidates; and division information having a longer allowable delay time remaining And an RR processing unit that determines a transmission assignment evenly for the corresponding mobile stations.
The radio base station apparatus, wherein the transmission order setting unit has a priority setting function for setting transmission allocation to the division information of the priority allocation unit in preference to the RR processing unit. The radio base station apparatus according to claim 2,
The RR processing unit includes a RR processing function that gives priority to the transmission assignment of the division information to the corresponding mobile station in order of increasing elapsed time since the last transmission assignment. Station equipment. The radio base station apparatus according to claim 3,
The transmission order setting means in the scheduling control unit is configured such that when resources that can be further allocated remain after preferential resource allocation processing for a group having a short allowable remaining time until the allowable delay, the RR processing unit side A radio base station apparatus comprising an additional allocation setting function for setting transmission allocation for the division information in descending order of priority. In the radio base station apparatus according to claim 1, 2, 3, or 4,
When the classification unit classifies the division information into a plurality of groups on the basis of the remaining time, the remaining time value T_rem of the delay time included in each division information calculated by the calculation unit
Compared to a preset threshold value T_th,
A radio base station apparatus comprising a function of distributing the plurality of pieces of division information to priority assignment means when T_rem ≦ T_th and to an RR processing unit when T_rem> T_th. In the radio base station apparatus according to claim 1, 2, 3, or 4,
When there is a plurality of transmission candidate division information for the corresponding one mobile station, the priority assigning means transmits the transmission candidate having the highest priority and the priority evaluation value for the remaining time to the transmission. A radio base station apparatus, wherein the radio base station apparatus deletes a transmission candidate other than the transmission candidates and a priority evaluation value relating to the remaining time, while transmitting to the order setting means. A radio base station scheduling setting method for radio communication with a plurality of mobile stations,
For each of a plurality of pieces of division information (packets) that are input transmission candidates, an allowable remaining time of a delay time allowed to be transmitted to a destination mobile station is calculated (allowable remaining time calculating step),
Based on the allowable delay information provided in the division information (packet) based on the calculated allowable remaining time, the division information is classified into at least one and a plurality of other groups (division information classification step),
A scheduling setting method for a radio base station, characterized in that a transmission order is preferentially set for the group of division information in the shortest remaining time among the classified division information (transmission order setting step). In the radio base station scheduling setting method according to claim 7,
When classifying the division information, priority of each piece of division information that configures a group of division information with a shorter allowable remaining time of the delay time as one transmission candidate is determined (priority assignment step), and the delay time The transmission allocation is determined so that the priority of each piece of division information that constitutes the group of division information having the longer allowable remaining time as the other transmission candidate is equal to the corresponding mobile stations (equal transmission assignment step) ,
A scheduling setting method for a radio base station, characterized in that, in transmitting each of these pieces of division information, the one transmission candidate is prioritized over the other transmission candidate according to the equal transmission allocation and the transmission order is set. The radio base station scheduling setting method according to claim 8,
When transmitting each of the pieces of division information, the remaining allowable time is long when resources that can be further allocated remain after preferential resource allocation processing for one transmission candidate with a short allowable remaining time until the allowable delay. A scheduling setting method for a radio base station, characterized in that transmission allocation is sequentially set for the other transmission candidates in descending order of priority. In a radio base station apparatus having a scheduling control unit that functions when performing radio communication with a plurality of mobile stations,
An allowable remaining time calculation function for calculating a remaining time of a delay time in which transmission waiting for a transmission destination mobile station is allowed for each of a plurality of pieces of division information (packets) that are input transmission candidates;
A division information classification function for classifying the division information into at least one group and a plurality of other groups based on information on an allowable delay time included in the division information (packet) with reference to the calculated allowable remaining time;
And a transmission order setting function for preferentially setting transmission opportunities for the group of the division information in the shortest remaining time among the classified division information,
Is executed by a computer provided in the scheduling control unit. A scheduling setting program for a radio base station, characterized in that In the scheduling setting program for a radio base station according to claim 10,
When classifying the division information, a priority assignment function for determining the priority of each piece of division information that configures a group of division information with a shorter allowable remaining time of the delay time as one transmission candidate;
An equal transmission allocation function for determining a transmission allocation so that the priority of each division information is equal to the corresponding mobile station, with the group of division information having a longer allowable remaining time of the delay time as the other transmission candidate;
And, in transmitting each of these pieces of division information, a transmission order setting function for setting the transmission order in preference to the other transmission candidate related to the equal transmission allocation,
Is executed by a computer provided in the scheduling control unit. A scheduling setting program for a radio base station, characterized in that The scheduling setting program for a radio base station according to claim 11,
The transmission order setting function for transmission of each of the division information is performed after the preferential resource allocation process for one transmission candidate with a short allowable remaining time until the allowable delay, and when further resources that can be allocated remain, It is configured to sequentially set transmission allocation in descending order of priority for the other transmission candidate with a long allowable remaining time,
A radio base station scheduling setting program characterized by causing a computer included in the scheduling control unit to execute this.

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