WO2006101168A1

WO2006101168A1 - Call reception control system and call reception control method

Info

Publication number: WO2006101168A1
Application number: PCT/JP2006/305822
Authority: WO
Inventors: Yasuhiko Matsunaga
Original assignee: Nec Corporation
Priority date: 2005-03-23
Filing date: 2006-03-23
Publication date: 2006-09-28
Also published as: JPWO2006101168A1

Abstract

A network management device (90) in a mobile communication system compares the quality of a communication service to be provided to a subscriber with a predetermined quality assurance item. As a result of the comparison, if any item violating the quality assurance or the degradation of quality allowance is detected and the call reception priority of the subscriber is less than the upper limit value, the call reception priority of the subscriber is increased by “1”. If any item violating the quality assurance or the degradation of the quality allowance is not detected, the call reception priority of the subscriber is returned to the default value. By setting the relation between the call reception control priority and the call reception control threshold in such a way that the higher the call reception control priority of a subscriber is, the lower the call reception control threshold value is, the degraded communication quality of the subscriber can be efficiently recovered.

Description

Specification

Call admission control system and call admission control method

Technical field

TECHNICAL FIELD [0001] The present invention relates to a call admission control system for accepting a call when a subscriber starts communication and during a handover between adjacent radio cells in a mobile communication system, and particularly to some of the subscribers. The present invention relates to a call admission control system that efficiently guarantees the quality of communication services.

Background art

In general, in a mobile communication system such as a public land mobile communication based on a cellular system, a plurality of subscribers belonging to a radio base station share a radio link for communication. Since the transmission capacity of the radio link is finite, if the number of subscribers requesting communication increases at the same time, the mobile communication system will not be able to receive new calls or handover calls in order to maintain the communication service quality for the subscribers already in communication. Perform call admission control to limit the number of simultaneous connections. As a typical example of conventional call admission control in a mobile communication system using code division multiple access (CDMA), reference 1 (Harri Holma, AnttiToskala, "WCDMA for UMTS: Radio Access for Third Generation Mobile Communications" , 3rd edition, John Wiley & Sons, 2004.), there are throughput-based call admission control and broadband power-based call admission control.

[0003] For example, in the case of throughput-based call admission control, the load amount standardized for each radio cell when a new call or handover call occurs is r ?, the call admission control threshold is r? Assuming that the increase in load expected when accepting is Δ r ?, the request is accepted if the following equation (1) is satisfied, and the connection is rejected if the following equation (1) is not satisfied.

[0004] 7? + Δ 7? ≤ rj th · · · (1)

This process is performed for both communication from the subscriber terminal in the radio base station (upstream) direction and communication from the radio base station to the subscriber terminal (downlink) direction. This call admission control is based on load 7 at the time of admission control, expected load increment Δ 7 ?, communication rate, spreading rate, required bit error rate, and adjacent cell power interference amount for each subscriber being accommodated. Depends on The estimation method is described in detail in Reference 1. Thereafter, transmission power, transfer rate, spreading code, etc. to the subscriber terminal and the radio base station are allocated to the call of the subscriber who has succeeded in call admission control. On the other hand, if the call admission control fails, communication is stopped. In addition, call requests are queued when they cannot be accepted immediately, and may be accepted when communication resources are available.

[0006] Further, examples of broadband power-based call admission control that uses electric energy instead of load include Document 1 and Document 2 (Japanese Patent Laid-Open No. 2003-348644). This is based on the following equation (2), where P is the transmission power standardized for each radio cell, Pth is the threshold for call admission control, and ΔP is the increase in power expected when a call is accepted. The request is accepted only when it is satisfied.

[0007] Ρ + Δ Ρ ≤ Pth "'{2)

[0008] Furthermore, by changing the method of call admission control depending on the type of call such as voice call, videophone, and packet data transfer, a call that maintains service quality for subscribers who use high priority services. There is also an admission control system. For example, reference 3 (Huan Chen, Sunil Kumar, Shi. Jay Shi, Dynamic and all Admission control and Resource Reservati on with Interference Guard Margin (IGM) for CDMA systems ", IEEE WirelessCommunications and Networking Conference (WCNC), 2003, vol. 3, pp. 1568-1572.), some communication resources are left as interference guard margins, and this is used when accepting high-priority service non-overover calls. A method for realizing a higher call completion rate than a connection request is disclosed.

[0009] Also, in Document 4 (Japanese Patent Application Laid-Open No. 2002-217956), a circuit-switched call and a packet-switching are performed by appropriately correcting the threshold of call admission control according to the number of subscribers performing data transfer by packet-switching. A method for efficiently accommodating calls is shown.

[0010] As described above, a call admission control system that uniformly applies a call admission control method according to a call type to all subscribers belonging to the same radio cell is already widely known.

[0011] Furthermore, in recent mobile communication systems, priority connection methods that always prioritize important communications of public authorities at the time of disaster and communications that require emergency related to the police and firefighting over general communications. There is something to have. This is specified in advance by the mobile communication system. A connection request from a preferential connection terminal or a connection request to a specific destination is identified as a connection request from another general terminal, and connection is preferentially permitted even when the network is congested. For example, in Document 5 (Japanese Patent Laid-Open No. 2002-300643), high-quality voice communication at a full rate is permitted for priority connection terminals regardless of the radio channel usage rate, and for other general terminals. It shows how to switch to a lower half rate when there is congestion.

[0012] As described above, a call admission control system that preferentially processes a connection request from a preferentially designated priority connection terminal regardless of the result of a past quality assurance operation at the terminal is also known. Yes.

Disclosure of the invention

Problems to be solved by the invention

However, in the conventional call admission control system that applies a uniform call admission control method to all the subscribers, even when the quality items of the communication service to be guaranteed differ depending on the subscriber, There is a problem that the control efficiency is poor because the control cannot be tailored to the subscriber.

[0014] For example, when a mobile communication carrier maintains a call loss rate of a voice call by a circuit switching method to less than 2% for some corporate users, a service level guarantee contract (hereinafter referred to as "SL A: Service In this case, if the call loss rate deteriorates to 5% in the wireless area covered by the SLA, it is originally only for corporate users who have signed an SLA. However, in the conventional call admission control system in which a uniform call admission control method is applied to all subscribers, the communication resources for voice calls for all subscribers may be increased. As the allocation amount is increased, there is a problem that the packet data communication throughput of all subscribers is lowered as a result.

[0015] Also, as in Reference 5, when a connection request from a designated priority connection terminal is preferentially processed regardless of the result of past quality assurance operations at the terminal, communication communication is more than necessary. There is a problem of allocating sources. For example, as in the previous example, corporate users have an SLA that keeps the call loss rate for voice calls using the circuit switching method below 2%. In that case, priority control should be performed only when the call loss rate during the contract period is close to 2% and the quality margin is reduced. However, in the conventional call admission control system, even if the call loss rate during the contract period is 0.1%, since the priority of the priority connection terminal is fixed, priority processing is always performed. There was a problem when the communication quality of subscribers deteriorated more than necessary.

[0016] Further, in the conventional call admission control system, when the mobile communication carrier guarantees the quality of the communication service to the subscriber, the subscriber joins each subscriber so as to satisfy a predetermined guarantee item. If service level monitoring and control are performed on a person-by-person basis, the control becomes complicated and the processing load increases!

[0017] Further, in the conventional call admission control system, if a contract is made to repay a part of the communication fee to the subscriber when the communication service quality assurance item cannot be satisfied, there is a shortage of communication resources. Depending on how the subscribers who refuse to connect are sometimes selected, there is a problem in that the amount of communication charges that the mobile carrier needs to refund increases.

[0018] Therefore, a main object of the present invention is to provide a call admission control system that enables a mobile communication carrier to efficiently realize quality assurance of communication services for a subscriber. Means to solve

[0019] The call admission control system according to the present invention includes a quality measuring means for measuring a communication service quality provided to a subscriber by a mobile communication carrier, and a communication service quality measured by the quality measuring means is predetermined. The quality judgment means to determine whether or not it satisfies the guarantee items of the product, and the guarantee items are satisfied when the quality judgment means meets the guarantee items and judges that the product is And a control means for controlling call acceptance as described above.

[0020] The call admission control method according to the present invention includes a step of measuring a communication service quality provided to a subscriber by a mobile communication carrier, and a communication service quality measured in the measuring step is predetermined. If the satisfaction item is satisfied at the step of determining whether or not the force is satisfied, and the step of determining is satisfied, the guarantee item is called to be satisfied. And a step of controlling reception. The invention's effect [0021] According to the present invention, the quality of communication service provided to a subscriber, a group of subscribers, etc. is measured, it is determined whether or not the quality of the communication service satisfies a predetermined guarantee item, and the guarantee item If it is determined that the service is satisfied, the call acceptance is controlled so that the guaranteed items are satisfied, so the quality assurance of the communication service contracted by the mobile operator to the subscriber or group of subscribers Can be effectively complied with and the penalty cost can be minimized when the warranty items cannot be satisfied.

Brief Description of Drawings

FIG. 1 is a configuration diagram of a mobile communication system in a first embodiment of the present invention.

FIG. 2 is a block diagram showing an internal configuration of the radio base station control device according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing the internal configuration of the network management apparatus in the first embodiment of the present invention.

FIG. 4 is a diagram showing the contents of communication service quality information in the first example of the present invention.

FIG. 5 is a diagram showing the contents of communication service quality assurance item information in the first exemplary embodiment of the present invention.

FIG. 6 is a flowchart showing call admission control processing in the first embodiment of the present invention.

FIG. 7 is a flowchart showing a communication service quality monitoring process in the first embodiment of the present invention.

FIG. 8 is a flowchart showing communication service quality comparison processing in the first exemplary embodiment of the present invention.

FIG. 9A is a graph showing the relationship between call admission control priority and call admission control threshold in the first example.

FIG. 9B is a graph showing the relationship between the call admission control priority and the transmission power allocation amount with respect to the reference value in the second embodiment.

FIG. 9C is a graph showing the relationship between the call admission control priority and the communication channel rate with respect to the reference value in the third example. FIG. 10 is a diagram showing the relationship between call admission control priority and assignable spreading codes in the fourth embodiment.

FIG. 11 is a flowchart showing call admission control processing in the fifth embodiment.

FIG. 12 is a flowchart showing a communication service quality comparison process in the sixth embodiment.

FIG. 13 is a diagram showing the contents of communication service quality information in the seventh embodiment.

FIG. 14 is a flowchart showing call admission control processing in the seventh embodiment.

FIG. 15 is a flowchart showing a communication service quality comparison process in the seventh embodiment.

FIG. 16 is a configuration diagram showing a mobile communication system and a service quality monitoring apparatus in an eighth embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

Next, embodiments of the present invention will be described in detail with reference to the drawings.

[0024] [First embodiment]

FIG. 1 is a configuration diagram showing a mobile communication system including a first embodiment of a call admission control system according to the present invention. Hereinafter, description will be given based on this drawing.

Subscriber terminals 10 and 11 are connected to a radio base station 30 via radio links 20 and 21. The subscriber terminal 12 is connected to the radio base station 31 via the radio link 22. Subscriber terminals 13 and 14 are connected to a radio base station 32 via radio links 23 and 24. The radio base station controller 50 is connected to the mobile communication core network 60 via a wired link 43, and to the subordinate radio base stations 30, 31, 32 via a wired link 40, 41, 42. Each sends and receives communication traffic and control traffic. The network management device 90 is connected to the radio base station control device 50 and the exchange station and server device in the mobile communication core network 60 via wired links 44 and 45, and performs network failure monitoring, communication service quality monitoring, and the like. The call admission control is performed when the subscriber terminal 10,... Newly starts communication or when the subscriber terminal 10,... Moves between the service areas 80, 81, 82 of each radio base station 30,. Done. FIG. 2 is a block diagram showing an internal configuration of the radio base station control apparatus in the first embodiment. The following description is based on FIGS. 1 and 2.

[0027] The radio base station controller 50 manages the allocation of communication resources in the subordinate subscriber terminals 10, ... and the radio base stations 30, .... Further, the radio base station control device 50 performs connection “disconnection” handover processing of the subscriber terminals 10. Further, the radio base station controller 50 performs data transfer processing with the mobile communication core network 60. Such a radio base station control device 50 includes a transceiver 100, a data transfer means 101, a control signal processing means 102, a communication quality measuring means 103, a connection request processing means 104, and a handover request processing means 1 05. Disconnection request processing means 106, operation parameter setting means 107, call admission control means 108, transmission power allocation means 109, transfer rate allocation means 110, spreading code allocation means 111, communication channel allocation means 112.

The transceiver 100 performs modulation / demodulation of signals exchanged between the radio base stations 30,... Under the subordinate and the exchange and network management device 90 of the mobile communication core network 60. The data transfer unit 101 performs a signal transfer process toward the destination of the received signal, and outputs the signal to the control signal processing unit 102 if the destination is a control signal of the radio base station controller 50. Here, the communication quality of the uplink radio signal from the subscriber terminal 10 to the radio base station 30, is notified from the transmitter / receiver 100 to the communication quality measuring means 103. On the other hand, the communication quality of the downlink radio signal from the radio base station 30, ... to the subscriber terminal 10, ... is determined by the control signal processing means 102 receiving the control signal transmitted from the subscriber terminal 10, ... Output to measuring means 103.

[0029] When the control signal processing unit 102 receives a control signal from the subscriber terminals 10 to 14, the mobile communication core network 60, or the network management device 90, the connection request processing unit 104, according to the type of the control signal, The distribution processing is performed to the handover request processing means 105, the disconnection request processing means 106, or the operation parameter setting means 107.

[0030] The communication quality measuring means 103 measures the communication quality of the uplink and uplink radio signals. This measurement result is output to operation parameter setting means 107, call admission control means 108, transmission power assignment means 109, transfer rate assignment means 110, spreading code assignment means 111, and communication channel assignment means 112. [0031] The connection request processing means 104 receives an outgoing call incoming connection request from the subordinate subscriber terminals 10, ..., and inquires of the call admission control means 108 whether or not the necessary communication resources can be secured. When communication resources can be secured, the connection request processing means 104 determines the communication channel rate according to the call type and the requested communication rate by the transfer rate assignment means 110. Then, spreading code assigning means 111 assigns spreading codes according to the required communication rate. The transmission power allocating means 109 allocates the transmission power corresponding to the required communication rate and the required error rate to the subscriber terminals 10,. In accordance with these settings, the communication channel assigning means 112 assigns a data transfer channel and a control channel. If the communication resource cannot be secured as a result of the call admission control, the connection request processing means 104 notifies the subordinate subscriber terminals 10,.

[0032] In response to the handover request from the subordinate subscriber terminals 10, ..., the handover request processing means 105 inquires of the call admission control means 108 whether or not the necessary communication resources can be secured. When communication resources can be secured, the handover request processing means 105 determines the communication channel rate according to the call type and the requested communication rate by the transfer rate assignment means 110. Then, spreading code assigning means 111 assigns spreading codes according to the required communication rate. The transmission power allocating means 109 allocates transmission power corresponding to the required communication rate and the required error rate to the subscriber terminals 10,. In accordance with these settings, the communication channel assigning means 112 assigns a data transfer channel and a control channel. If the communication resource cannot be secured as a result of the call admission control, the handover request processing means 105 notifies the subordinate subscriber terminals 10,.

When disconnection request processing means 106 detects the end of communication, call admission control means 108 releases communication resources such as communication channels, spreading codes, and transmission power that have been secured so far.

[0034] When the operation parameter setting means 107 is instructed to change the operation parameter setting from the network management device 90, the operation parameter setting means 107 allocates the transmission power to the call admission control means 1 08 if the call admission control threshold setting is changed. If the method is changed, the transmission power allocation means 109 is changed to the transmission power allocation means 109. The contents are output to transmission rate assigning means 110, spreading code assigning means 111 or communication channel assigning means 112, respectively.

Here, when the call admission control means 108 receives an instruction from the operation parameter setting means 107, the call admission control threshold value and the setting of forced disconnection of the call of another subscriber are changed based on this instruction. I do. In addition, when receiving an instruction from the operation parameter setting unit 107, the transmission power allocation unit 109 changes the setting of the transmission power allocation method based on this instruction. In addition, when the transmission power allocation unit 109, the transfer rate allocation unit 110, the spreading code allocation unit 111, and the communication channel allocation unit 112 receive an instruction to change the communication resource allocation method from the operation parameter setting unit 107, Change the communication resource allocation method settings. For example, when receiving an instruction from the operation parameter setting means 107, the transfer rate assignment means 110 changes the setting of the transfer rate assignment method based on this instruction. Further, upon receiving an instruction from the operation parameter setting means 107, the spreading code assigning means 111 changes the setting of the spreading code assignment method based on this instruction. Further, when receiving an instruction from the operation parameter setting means 107, the communication channel assignment means 112 changes the setting of the communication channel assignment method based on this instruction!

FIG. 3 is a block diagram showing the internal configuration of the network management apparatus in the present embodiment. Hereinafter, a description will be given based on FIGS.

The network management device 90 performs operation parameter provisioning, network failure monitoring, communication service quality monitoring, and the like in each device in the mobile communication system. Such a network management device 90 includes a transceiver 200, data transfer means 201, failure display means 202, monitoring information input means 203, operation parameter setting means 204, communication service quality monitoring means 205, communication Service quality comparison means 206, wireless area design means 207, communication service quality storage means 208, and quality assurance item storage means 209 are provided.

The transceiver 200 transmits and receives various types of information to and from the exchange station and server device in the radio base station control device 50 and the mobile communication core network 60 via the wired links 44 and 45.

The data transfer unit 201 transfers the information received by the transceiver 200 to the monitoring information input unit 203 and the operation parameter setting unit 204. In addition, the data transfer means 201 The information received from the information input means 203 and the operation parameter setting means 204 is sent to the transceiver 200 in a third order.

The fault display unit 202 displays the content of the fault based on an instruction from the communication service quality monitoring unit 205.

The monitoring information input means 203 outputs information such as network monitoring information received by the transceiver 200 via the data transfer means 201 to the communication service quality monitoring means 205. Also, the information input from the communication service quality monitoring unit 205 is output to the transceiver 200 via the data transfer unit 201.

The operation parameter setting unit 204 corrects the operation parameter based on an instruction from the communication service quality comparison unit 206 and the radio area design unit 207, and this is corrected by the radio base station via the data transfer unit 201 and the transceiver 200. Output to controller 50. Also, the operation parameter values that are currently set are output to the communication service quality comparison means 206 and the radio area design means 207.

[0041] When the network monitoring information is input via the monitoring information input unit 203, the communication service quality monitoring unit 205 determines the presence or absence of a network failure. Display the details of the failure. Further, the communication service quality monitoring means 205 stores the content of the communication service quality monitored at regular intervals in the communication service quality storage means 208 regardless of the presence or absence of a failure.

[0042] The communication service quality comparison unit 206 periodically compares the communication service quality provided to the subscriber with the quality assurance items of the communication service for the subscriber stored in the quality assurance item storage unit 209. And do not satisfy quality assurance items! In the case of ヽ or when the quality margin is lowered, the operation parameter setting means 204 is notified of parameters to be corrected as appropriate.

[0043] The wireless area design means 207 estimates the quality of the communication service that can be provided based on the input of topographic information and radio wave propagation conditions of the service target area, and is optimal for the operation parameter setting means 2004. Output operational parameters.

FIG. 4 is a diagram showing an example of communication service quality information stored in the communication service quality storage means of FIG. This will be described below with reference to FIGS. 3 and 4. [0045] The communication service quality information 400 is classified into subscriber group statistical information 410, 420, 430 of service classes A, B, and C according to the content of the communication service provided to the subscriber. The Service class A subscriber group statistical information 410 includes service class A subscriber group overall statistical information 411, subscriber A1 statistical information 412, subscriber A 2 statistical information 413, and subscriber A3. Consists of statistical information 414,.

[0046] Table 1 shows an example of subscriber (group) statistical information. The following description is based on this drawing.

[0047] [Table 1]

As shown in the figure, the format of the subscriber group overall statistical information for each service class and the statistical information for each subscriber is the same. Each row in Table 1 represents the acquired statistical items. In each row in this example, connection request count 301, connection failure count 302, call setup time 30 3, communication normal completion count 304, communication error completion count 305, average transfer rate 306, average transfer rate Transmission delay amount 307, average transfer delay jitter 308, average frame loss rate 309, failure history 310, and call admission control priority 311 are defined. Each column in Table 1 represents the types of communication services available to subscribers, and defines circuit-switched voice call 320, circuit-switched videophone 321, circuit-switched data transfer 322, and packet-switched data transfer 323. . For each element, the cumulative value or average value of the number of occurrences of the event during the monitoring period is recorded, and NZA (Not Available) is recorded for those that do not require statistics. In addition, in the failure history item, a list of network failure events in the monitoring organization is described.

FIG. 5 is a table showing an example of communication service quality assurance item information. The following description is based on this drawing.

[0050] Communication service quality assurance item information 450 is defined for each service class, and quality assurance items 451, 452, and 453 corresponding to three types of service classes A, B, and C are shown. For example, service class A is the premium service with the highest guaranteed communication quality level, service class B is the basic service for corporations with limited guarantee items than service class A, and service class C is not contracted to guarantee the communication quality. Correspondence is set in advance like general services.

[0051] Table 2 is a table showing an example of communication service quality assurance items for each service class. The following explanation is based on this table.

[0052] [Table 2]

[0053] Table 2 shows the contents of the communication service quality assurance item 330 for each service class. Each row in Table 2 shows the guarantee items of the communication service. In this example, call setup completion rate 331, call setup time 332, communication normal completion rate 333, average transfer rate 334, average transfer delay amount 335, average transfer delay jitter 336, average frame loss rate 337, target area 338, area coverage rate 339, equipment operation time rate 340, failure recovery time 341, refund method 342 for violation and default call acceptance priority 343 are specified. Each column in Table 2 corresponds to each communication service provided by mobile operators to users. Items that are not guaranteed, such as call setup time, average transfer delay jitter, and area coverage, are displayed as NZA (Not Available).

[0054] The configuration of the first embodiment of the present invention has been described in detail above. The subscriber terminals 10 to 14 in FIG. The radio base stations 30 to 32 are well known to those skilled in the art, and are not directly related to the present invention, and thus detailed configurations thereof are omitted. The subordinate concepts of “quality measurement means”, “quality determination means” and “control means” described in the claims are “monitoring information input means 203, communication service quality” shown in FIGS. 2 and 3, respectively. Monitoring means 205 and communication service quality storage means 208 "," communication service quality comparison means 206, communication service quality storage means 208 and quality assurance item storage means 209 "and" control signal processing means 102, connection request processing means 104, handover " Request processing unit 105, disconnection request processing unit 106, operation parameter setting unit 107, call admission control unit 108, transmission power allocation unit 109, transmission rate allocation unit 110, spreading code allocation unit 111, and communication channel allocation unit 112 ” To do.

Next, the operation of the call admission control system according to the present embodiment will be described.

FIG. 6 is a flowchart showing call admission control processing by call admission control means 108 in radio base station controller 50. The following explanation is based on FIGS. 1 to 6 and Tables 1 and 2.

[0057] First, when receiving an incoming / outgoing connection request or a handover request input to the subscriber terminals 10, ... (steps 501 and 502), the call admission control means 108 calls the call admission priority corresponding to the subscriber and the service. The degree i is acquired (step 505). For example, in the case of a mobile communication system based on the specifications of 3GPP (Third Generation Partnership Project), a mobile base station controller is connected from the mobile communication core network 60 when a call is made to a subscriber terminal 10, The “Allocation / Retention Priority” parameter contained in the RAB Parameters information element of the RABAssignment Request message entered in 50 is suitable for use for this purpose. In the case of handover, Allocation / Retention Priority information can be referred to from the identifier of RAB (Radio Access Bearer) that the subscriber terminal has already established. The details of the Allocation / Retention Priority parameter are detailed in Section 9.2.1.3. Of Reference 6 (3GPP TS 25. 413 V 4.0.0, “UTRAN Iu interface RANAP signaling (Release 4)”, 2001.). Has been.

Subsequently, the call admission control means 108 calculates the uplink Z downlink load increment Δ 7? UpZ A 7? Down that occurs when the call is accepted, such as the call type, communication rate, and required frame error rate. (Step 506). Based on this increase in load, if the call is accepted, the upper limit value of the load for call acceptance priority i, r? Th-up (i), r? Th-down (i) is not exceeded. Check (Step 50 7), and then check whether the total priority load exceeds the upper limit values η th-up (all) and η th_down (all) (Step 508). If neither is a problem (Steps 507, 508: YE

5) After assigning the spreading code (step 509), transmission power (step 510), communication channel transfer rate (step 511), communication channel (step 512), and updating the up / down load ( At step 513), the connection 'handover request acceptance response is transmitted (step 514), and the process ends (step 515).

[0059] On the other hand, if there is a problem due to misalignment from step 507 to step 510 (steps 507 to 510: NO), the call admission control means 108 creates and sends a rejection response for the connection “no-over request”. (Step 516) and the process ends (Step 517).

[0060] If a disconnection request is received (step 503), the call admission control means 108 acquires the admission priority of the corresponding call (step 518), updates the up / down load, and ( Step 519) releases various communication resources such as spreading code, transmission power, and communication channel (steps 520 to 522), transmits a disconnection response (step 523), and ends the processing (step 524).

[0061] Further, an operation parameter setting request is received from the network management device 90 (step 504), and the thresholds for call admission control (th-up (i), 7? Th-down (i), η th-up (all ), η th-down (all)), the threshold is updated (step 525) and the process is terminated (step 52).

6).

FIG. 7 is a flowchart showing communication service quality processing by the communication service quality monitoring means 205 in the network management device 90. The following explanation is based on FIGS. 3 and 7.

First, monitoring information is input to the communication service quality monitoring means 205 (step 531). This monitoring information is various information on the network to be monitored by the communication service quality monitoring means 205, such as communication quality between the subscriber terminals 10,... And the radio base stations 30,. When the monitoring information is input, the communication service quality monitoring means 205 determines whether or not the network information is included in the monitoring information (step 532). Contains fault information If so (step 532: YES), the communication service quality monitoring means 205 outputs the failure information to the failure display means 202 (step 534), causes the communication service quality storage means 208 to store the communication service quality (step 533), End processing (step 535). On the other hand, if the monitoring information is not included (step 532: NO), the communication service quality monitoring means 205 stores the communication service quality in the communication service quality storage means 208 (step 533) and ends the processing (step 533). Step 535). In this way, when failure information is included, by outputting the failure information to the failure display means 202, it is possible to easily identify that the deterioration of communication quality is due to the failure. It is possible to deal with the deterioration more easily.

FIG. 8 is a flowchart showing a communication service quality comparison process by the communication service quality comparison means 206 in the network management device 90. The following explanation is based on Figs. 3 and 8.

[0065] The communication service quality comparison unit 206 compares the quality of the communication service provided to the subscriber with the guarantee items at the time of the request from the communication service quality monitoring unit 205 or at predetermined intervals. Start (step 540). First, a service class j to be compared is selected (step 541), and quality assurance item information defined for the service class j is obtained with reference to the quality assurance item storage means 209 (step 542). Subsequently, the subscriber group statistical information of the service class j is referred from the communication service quality storage means 208 (step 543), and the statistical information of the subscribers belonging to the service class j is sequentially selected (step 544). Subsequently, the communication service quality calculation (step 545) within the subscriber monitoring period based on the subscriber statistical information is performed as follows, for example, for the call setup completion rate and the communication normal completion rate.

[0066] Call setup completion rate = 1 (number of connection failures Z number of connection requests)

Communication normal completion rate = call setting completion rate X (1—communication error completion count Z (communication normal completion count + communication error completion count))

[0067] Regarding other items, statistical information and guaranteed items can generally be directly compared. Subsequently, the quality assurance items of service class j are compared for the communication service quality during the monitoring period of the subscriber (step 546), and a quality assurance violation item or a decrease in quality margin is detected (step 547: YES) ) Indicates that the subscriber's call admission priority is not less than the upper limit. (Step 549: NO), the call acceptance priority of the subscriber is increased by “1” (step 550). on the other hand. If a quality assurance violation item or a drop in quality margin is not detected (step 547: NO), the call reception priority of the subscriber is returned to the default value (step 548). The setting change of the call reception priority is performed by the operation parameter setting means 204.

[0068] When all the communication quality comparison processing for the subscribers belonging to service class j is completed (step 544: no next subscriber), processing for the next service class is performed (step 541). When the processing for all service classes has been completed (step 541: selection completed), the subscriber information whose call reception priority has been changed is sent to the radio base station controller 50 and the mobile communication core network 60 switching center. Notification is made (step 551) and the process is terminated.

[0069] Here, if the relationship between the call admission control priority and the call admission control threshold is defined as shown in Fig. 9A, the call admission control threshold becomes lower for subscribers with higher priorities, so that the call admission is accepted. It is possible to recover the deteriorated communication service quality. Thus, when the call admission control threshold value is adaptively changed, it is particularly effective for recovery of the call setup completion rate and the communication normal completion rate. The relationship between the call admission control threshold and the call admission control priority may be fixed, but may be corrected from the network management device 90 to the radio base station control device 50 as necessary. Anyway!

[0070] [Second Example]

Next, a second embodiment of the call admission control system according to the present invention will be described.

[0071] Although the basic configuration of this embodiment is the same as that of the first embodiment described above, the transmission power allocation method for subscriber terminals and radio base stations has been devised. Figure 9B shows the relationship between the priority of call admission control and the allocated amount with respect to the reference value of transmission power. In this case, when the priority power of call admission control is “0” and “2”, the specified transmission power is allocated as it is, and when the priority of call admission control is “1” and “3”, respectively. Allocate transmission power up to P (l) and P (3) times the reference value. In this way, when a quality assurance violation item or a decrease in quality margin is detected, control for effective restoration of the normal communication completion rate and frame loss rate can be achieved by temporarily increasing the transmission power allocation amount. It can be performed.

[0072] [Third embodiment]

Next, a third embodiment of the call admission control system according to the present invention will be described. [0073] Although the basic configuration of this embodiment is the same as that of the first embodiment described above, the method for assigning the communication channel rate to the subscriber terminal is devised. An example of this is shown in FIG. 9C. Referring to FIG. 9C, when the call admission control priority is “0” and “2”, the reference value of the communication channel rate is set as it is, and when the call admission control priority is “1” and “3”. Respectively increase the transmission power to R (1) and R (3) times the reference value. In this way, when a quality assurance violation item or a decrease in quality margin is detected, the speed of the communication channel rate is temporarily increased, so that the average transfer rate, average transfer delay amount, average transfer delay time, etc. Effective control over recovery can be performed.

[0074] [Fourth embodiment]

Next, a fourth embodiment of the call admission control system according to the present invention will be described.

[0075] The basic configuration of this embodiment is the same as that of the first embodiment described above. However, when the mobile communication system uses a multi-access scheme based on the CDMA scheme, a spreading code for the subscriber terminal is used. It is something that is devised with respect to the allocation of. An example of this is shown in FIG. Referring to FIG. 10, out of all assignable spreading codes, some spreading codes 900 used for control such as uplink synchronization, pilot signal, cell selection, transmission power control, etc. are reserved in advance. The other spreading codes used for subscriber traffic transmission are the spreading code 901 that can be used by subscriber terminals of all call admission control priorities, and the spreading code that can be used by subscriber terminals with priority level S “l” or higher. The code 902 is classified into a spread code 903 that can be used by subscriber terminals with a priority of “2” or higher, and a spread code 904 that can be used by subscriber terminals with a priority of “3” or higher. In this way, by making spreading code assignment easier for subscriber terminals with higher priority, the possibility of failure in call admission control due to exhaustion of code resources of subscriber terminals with higher priority can be reduced. . In this embodiment, particularly effective control can be performed for recovery of the call setup completion rate and the communication normal completion rate.

[0076] [Fifth embodiment]

Next, a fifth embodiment of the call admission control system according to the present invention will be described.

FIG. 11 is a flowchart showing call admission control processing in the present embodiment. Referring to FIG. 11, in the present embodiment, the processing in the case where a connection request or a handover request is received, step 605 to step 610 are processed in the call acceptance in the first embodiment shown in FIG. This is the same as the operation flow of the attached control process. In the present embodiment, when acquisition of communication resources for a call fails in any of Step 607 to Step 610, if there is a subscriber having a lower call reception priority than the subscriber (Step 616: YES), The lower priority subscriber's call is disconnected (step 617), and the connection request or handover request is temporarily queued until the subscriber's call is accepted using the communication resource released by the disconnection response. To put it on hold (step 618). Other operations are the same as those in the call admission control process in the first embodiment shown in FIG. According to this embodiment, even when communication resources are insufficient, low priority calls can be forcibly disconnected and communication resources can be secured. Therefore, especially for call setup completion rate and normal communication completion rate recovery. Effective control can be performed.

[Sixth embodiment]

Next, a sixth embodiment of the call admission control system according to the present invention will be described.

FIG. 12 shows an operation flow of communication service quality comparison processing in the present embodiment. Referring to FIG. 12, steps 640 to 646 are the same as the operation flow of the communication service quality comparison process in the first embodiment shown in FIG. 8. In this example, if a violation of quality assurance items or a decrease in quality margin is detected at step 647 (step 647: YES), the amount returned to the subscriber at the time of violation of quality assurance is above the reference value (step 649: YES), and if the call admission control priority of the subscriber is less than “upper limit value 1” (step 650: YES), the call admission priority of the subscriber is increased by “2” at a time (step 651). ). The amount returned when the quality assurance is breached for the customer is less than the reference value (step 649: NO), or the call admission control priority of the subscriber has already reached the “upper limit value—1” (step 650: NO) ) If the subscriber's call admission priority is less than the upper limit (step 652: YES), the subscriber's call admission control is increased by “1” (step 653). According to this example, the quality of the communication service does not meet the guarantee items!回復 Since the communication service quality recovery control operation is preferentially performed for the subscriber, it is possible to minimize the monetary loss due to the violation of the communication service quality contract of the mobile carrier.

[0080] [Seventh embodiment]

Next, a description will be given of a seventh embodiment of the call admission control system according to the present invention. [0081] In the first to sixth embodiments, communication service quality monitoring and control operations are performed in units of subscribers, whereas in this embodiment, in units of subscriber groups having the same service class. By performing quality monitoring and control operations, the processing load on the mobile communication system is reduced. The contents of the communication service quality information 400 in this embodiment are as shown in FIG. 13, and the statistics information for the entire subscriber group belonging to the service classes A, B, and C is not taken without taking statistics for each subscriber 471, 481, Save only 482.

FIG. 14 shows an operation flow of call admission control processing in the present embodiment. In Fig. 6 and Fig. 11, the load threshold exceeded was checked according to the priority of the subscriber. In this example, the load threshold exceeded was checked for each service class. Assign. For example, in the case of a mobile communication system based on the 3GPP specifications, a connection request for a subscriber terminal and a request for a handover request may be determined from the mobile communication core network at the time of a subscriber terminal's outgoing / incoming connection request. The “Traffic Class” parameter included in the RAB Parameters information element of the RAB Assignment Request message input to the radio base station controller is suitable for this purpose. The details of the “Traffic Class” parameter are described in detail in Section 9.2.1.3. The service class can also be identified by a method in which the correspondence relationship between the priority specified by “Allocation / Retention Priority” in the first embodiment and the service class is determined in advance.

FIG. 15 shows an operation flow of communication service quality comparison processing in the present embodiment. In this example, communication service quality during the monitoring period of subscribers for the selected service class is compared with quality assurance items (step 745), and a violation of quality assurance items or a decrease in quality margin is detected. (Step 746: NO) If the call acceptance priority of the subscriber group for the service class is not less than the upper limit (Step 748), raise the call admission control priority of the entire subscriber group belonging to the service class by “1”. (Step 749). In this way, in the seventh embodiment, quality monitoring / correction control is performed in units of subscriber groups belonging to the same service class rather than in units of subscribers. In addition, the processing load on the radio base station control device 30 and the exchange station in the mobile communication core network can be greatly reduced.

[0084] [Eighth embodiment] Next, an eighth embodiment of the call admission control system according to the present invention will be described.

In this embodiment, a mode is shown in which a mobile communication company entrusts service quality monitoring to an external company. At this time, service quality monitoring is not performed for each terminal or service class within the mobile carrier network. In FIG. 16, the mobile terminals 15 and 16 of the corporate subscribers who have signed a quality assurance contract with the mobile communication carrier for the communication service are connected to the service quality monitoring device 1030 connected outside the mobile communication carrier network 1000. Communication service quality monitoring results 1010 and 1011 are transmitted. The communication service quality monitoring results 1010, 1 011 are the same as the subscriber statistical information 300 in the first embodiment. In addition, if the service quality guarantee contract includes conditions covered by the guarantee, the area information at the time of monitoring the communication service quality may be included. The service quality monitoring device 1030 compares the service quality assurance items previously determined for the legal subscriber terminals 15 and 16 with the communication service quality monitoring results, and detects violations of quality assurance items or a decrease in quality margin. In this case, the terminal information of quality margin reduction for the subscriber is notified from the service quality monitoring device 1030 to the network management device 90 of the mobile communication carrier. In response to this, if the network management device 90 temporarily raises the call admission control priority for corporate subscriber terminals whose quality margin has declined, it is possible to comply with the contracted service quality assurance items. It becomes possible. As described above, according to this embodiment, service quality management and control can be performed without managing communication service quality for each terminal and comparing contracted quality assurance items within the mobile communication carrier. Can do.

[0086] As described above, according to the present invention, by performing communication service quality monitoring and communication resource allocation according to subscribers, mobile communication carriers can efficiently communicate with subscribers. Service quality assurance can be realized. In addition, the processing load can be reduced by monitoring the quality of communication services and controlling the quality of subscribers that have the same quality assurance items in units of subscribers. Furthermore, by selecting subscribers who refuse connection when there is a shortage of communication resources in accordance with the amount of money returned to the subscriber when they cannot satisfy the quality assurance items, mobile communication due to shortage of communication resources. It can minimize the decrease in revenues of operators.

[0087] Further, the present invention can be summarized as follows. Network pipe in mobile communication system The physical device compares the communication service quality provided to the subscriber with a predetermined quality assurance item. If, as a result of the comparison, a quality assurance violation item or a drop in quality margin is detected, if the subscriber's call acceptance priority is less than the upper limit, the subscriber's call acceptance priority is increased by “1”. On the other hand, if a quality assurance violation item or a drop in quality margin is not detected, the call reception priority of the subscriber is returned to the default value. Here, by setting the relationship between the call admission control priority and the call admission control threshold so that the call admission control threshold becomes lower for subscribers with higher priority, the communication service quality deteriorates. Communication quality can be recovered efficiently. Similarly, other communication resources such as transmission power, communication channel rate, spreading code, etc. are preferentially allocated to the subscriber terminals in which quality assurance violation items or deterioration of quality margin are detected. In addition, by increasing the priority of call admission control for subscriber terminals that have a high penalty for quality assurance violations, it is possible to reduce the financial loss of the mobile operator. As a result, in the mobile communication system, according to the communication service quality item that the subscriber has contracted with the mobile communication carrier, the communication service quality is monitored and the communication resources are allocated according to the subscriber (group). Efficiently comply with quality assurance, and minimize penalty costs incurred when the warranty items cannot be satisfied.

Industrial applicability

The present invention can be applied to various mobile communication systems.

Claims

The scope of the claims

[1] Quality measurement means for measuring the quality of communication services provided by mobile operators to subscribers;

A quality judging means for judging whether or not the communication service quality measured by the quality measuring means satisfies a predetermined guarantee item;

Control means for controlling call acceptance so that the guarantee item is satisfied when the quality judgment means determines that the guarantee item is not satisfied;

A call admission control system comprising:

[2] The control means temporarily raises the priority of call admission control over other subscribers when the quality judgment means determines that the guarantee item is satisfied! / ,! The operation parameter setting means for returning the priority of the call admission control to the original value when the quality judgment means determines that the guarantee item is satisfied again.

The call admission control system according to claim 1, further comprising:

[3] When the quality determination unit determines that the guarantee item is satisfied! /, N! /, The control unit is configured to start communication of the subscriber and perform handover to an adjacent radio base station. In any one of these cases, the acceptance threshold value for call admission control is temporarily relaxed, and when the quality judgment means again determines that the guarantee item is satisfied, the acceptance threshold value is returned to the original value. Call admission control means to return

The call admission control system according to claim 1, further comprising:

[4] The control means, when the quality judgment means satisfies the guarantee item and is judged as! / ヽ !! at the start of communication of the subscriber and at the time of handover to the adjacent radio base station. When the transmission power amount allocated to the subscriber terminal and the radio base station is temporarily increased in either one of them, and the quality determination means determines that the guarantee item is satisfied again, the transmission power amount Power allocation means to restore the original value

The call admission control system according to claim 1, further comprising:

[5] When the quality determination means determines that the guarantee item is satisfied! /, N! /, The control means, when the subscriber starts communication and at the time of handover to an adjacent radio base station In either one of the above, the uplink direction from the subscriber terminal to the radio base station and the radio base station Temporarily increases the transfer rate assigned to one of the downlink directions from the subscriber terminal to the subscriber terminal, and when the quality determination means determines that the guarantee item is satisfied again, the transfer rate is changed to the original value. Transfer rate allocation means to return to

The call admission control system according to claim 1, further comprising:

[6] Used in mobile communication systems based on multiple access based on code division multiple access,

The control means, when the quality judgment means satisfies the guarantee item and determines that it is! / ヽ! ヽ, either when the subscriber starts communication or at the time of handover to an adjacent radio base station , Temporarily assigns a spreading code preferentially over other subscribers, and when it is judged again by the quality judging means that the guarantee item is satisfied, it is based on the assigned priority of the spreading code. Return spreading code assigning means

The call admission control system according to claim 1, further comprising:

[7] The control means forcibly disconnects another subscriber's call temporarily when the quality judgment means determines that the guarantee item is satisfied! / ,! Call admission control means for stopping forced disconnection of the call of the other subscriber when it is determined by the quality determination means that the guarantee item is satisfied.

The call admission control system according to claim 1, further comprising:

[8] When there are a plurality of subscribers determined to satisfy the guarantee item by the quality judging unit and to be judged as! /, N! /, The control means is used when the guarantee item is not fulfilled. Operation parameter setting means for controlling call reception so that the guarantee item is satisfied with priority given to the subscriber by giving priority to the return amount paid from the mobile carrier!

The call admission control system according to claim 1, further comprising:

[9] The quality measuring means measures communication service quality provided to a subscriber group composed of a plurality of subscribers having the same communication service quality guarantee items, and the quality determining means includes: Determining whether the quality of communication service for the subscriber group measured by the quality measuring means satisfies a predetermined guarantee item!

The control means controls call acceptance for the subscriber group so that the guarantee item is satisfied when the quality judgment means satisfies the guarantee item and determines that the guarantee item is satisfied. Ru

The call admission control system according to claim 1, wherein:

[10] The quality determination means, as the predetermined guarantee item, for each type of service to be provided

Area for guaranteeing communication service quality, area coverage rate for guaranteeing communication service quality, operating time rate of equipment constituting mobile communication system, recovery time in case of failure of equipment constituting mobile communication system, call setup completion rate, The call setup time, call normal communication completion rate, call throughput, call network transfer delay amount, call network transfer delay jitter amount, and call frame loss rate Judging whether or not you have power

The call admission control system according to claim 1, wherein:

[11] When it is measured by the quality measurement means that a failure has occurred in the communication service, a display means for displaying the failure

The call admission control system according to claim 1, further comprising:

[12] measuring the quality of communication service provided by the mobile operator to the subscriber;

Determining whether the communication service quality measured in the measuring step satisfies a predetermined guarantee item!

Controlling the call admission so that the guarantee item is satisfied when it is determined that the guarantee item is satisfied and the warranty item is satisfied in the determining step.

A call admission control method comprising:

[13] The controlling step includes:

A step of temporarily raising the priority of call admission control over other subscribers when it is determined that the guarantee item is satisfied and is determined to be inadequate in the determining step;

A step of returning the priority of the call admission control to the original value when it is determined that the guarantee item is satisfied!

The call admission control method according to claim 12, further comprising:

[14] The controlling step includes:

When it is determined that the guarantee item satisfies the guarantee item in the determination step, Temporarily relaxing the acceptance threshold of call admission control at either the subscriber's start of communication or at the time of handover to an adjacent radio base station;

A step of returning the acceptance threshold to the original value when it is determined that the guarantee item is satisfied /!

The call admission control method according to claim 12, further comprising:

[15] The controlling step includes:

When it is determined that the guarantee item is satisfied and is determined to be で by the determination step, the subscriber terminal and the radio base station either at the start of communication of the subscriber or at the time of handover to an adjacent radio base station Temporarily increasing the amount of transmit power allocated to

A step of returning the transmission power amount to the original value when it is determined that the guarantee item is satisfied /!

The call admission control method according to claim 12, further comprising:

[16] The control step includes:

When it is determined in the determining step that the guarantee item is satisfied and the error is determined to be ヽ, the subscriber terminal to the radio base station either at the start of communication of the subscriber or at the time of handover to an adjacent radio base station Temporarily increasing the transfer rate assigned to either the upstream direction to the mobile station and the downstream direction from the radio base station to the subscriber terminal; and

A step of returning the transfer rate to the original value when it is determined that the guarantee item is satisfied!

The call admission control method according to claim 12, further comprising:

[17] Used in mobile communication systems based on multi-access schemes based on code division multiple access,

The controlling step includes

When it is determined in the determination step that the guarantee items are satisfied and the connection is determined to be ヽヽ, either at the start of communication of the subscriber or at the time of handover to an adjacent radio base station, temporarily Assigning a spreading code preferentially over the user, A step of returning the assigned priority of the spreading code to the original when it is determined that the guarantee item is satisfied!

The call admission control method according to claim 12, further comprising:

[18] The controlling step includes:

A step of forcibly disconnecting another subscriber's call temporarily when the step of determining satisfies the guarantee item and determines that the case is obscene;

Stopping the forced disconnection for the call of the other subscriber when it is determined again that the guarantee item is satisfied!

The call admission control method according to claim 12, further comprising:

[19] The controlling step includes:

When there are a plurality of subscribers who are judged to be obscene by satisfying the guarantee item in the judging step, the return amount paid from the mobile carrier when the guarantee item is not fulfilled is large. ! / ヽ Steps to control call acceptance so that the warranty items are satisfied in preference to subscribers

The call admission control method according to claim 12, further comprising:

[20] The measuring step measures the communication service quality provided to a subscriber group composed of a plurality of subscribers having the same communication service quality guarantee item, and the determining step includes the step of determining Determine whether the communication service quality for the subscriber group measured by the quality measurement means satisfies a predetermined guarantee item!

The controlling step controls call acceptance for the subscriber group so that the guarantee item is satisfied when the quality judgment means satisfies the guarantee item and determines that the guarantee item is satisfied!

13. The call admission control method according to claim 12, wherein

[21] The step of determining includes

As the predetermined guarantee items, for each type of service to be provided, an area for guaranteeing communication service quality, an area coverage ratio for guaranteeing communication service quality, an operating time rate of devices constituting the mobile communication system, and a mobile communication system are configured. Recovery time, call setup completion rate, call setup time, normal call completion rate, call sloop The network transfer delay amount of the call, the network transfer delay jitter amount of the call, and the medium strength of the call frame loss rate satisfy at least one of the selected ones. 13. The call admission control method according to claim 12.

When the measuring step determines that a failure has occurred in the communication service, the step of displaying the failure

The call admission control method according to claim 12, further comprising: