Patent Application
20050111410
The present invention relates to a radio communication system capable of delivering signals to mobile stations via a base station and relates to a repeating apparatus to repeat signals between a mobile station and a radio communication controller.
The packet communication service provided by FOMA (registered trademark), one of third generation (3G) cellular phone systems, uses an apparatus (hereafter referred to as a traffic collection apparatus) having the function (IWF: inter working function) to collect traffic. This apparatus receives packet delivery acknowledgment (ACK) from a mobile station (UE) via a base station (Node-B). Then, the apparatus counts the number of communication packets downstream to the mobile station and collects the number of counted packets as the traffic corresponding to the total amount of communication data for mobile station users.
The packet delivery acknowledgment is performed on the link protocol (RLC: radio link control protocol) layer. Accordingly, an operation mode for the RLC protocol is selected to be acknowledged mode (AM). In consideration for this, chargeable services such as data delivery services are limited to the RLC acknowledged data transfer mode, i.e., an operation mode capable of exchanging delivery acknowledgment information (STATUS PDU).
Patent document 1 describes the technology known as an example of charging systems in the second generation cellular phone service earlier than the third generation equivalent. The charging system described in patent document 1 allows a packet data terminal apparatus (user's cellular phone terminal) to perform packet communication via a base station. Service supply nodes, gateway support nodes, and the like are connected to a mobile communication network and collect traffic concerning the amount of network utilization. The collected traffic is used to charge users.
[Patent Document]
Japanese Translation of Unexamined PCT Appln. No. 2000-503825.
As mentioned above, charging services in the third generation cellular phone system are feasible only in the RLC acknowledged data transfer mode.
However, the RLC acknowledged data transfer mode uses the link protocol layer for the packet delivery acknowledgment. Data delivery starts after the packet delivery acknowledgment. If the packet delivery acknowledgment fails, for example, RLC retransmission may occur to cause a delay between apparatuses in the network. In such case, the throughput degrades. Accordingly, the RLC acknowledged data transfer mode is not always suited for data delivery services that require high realtime performance.
In the future, an increasing demand is anticipated for data delivery services requiring fast and high realtime performance such as delivery services of video streaming data. From this viewpoint, it is expected to realize data delivery services using the other operation modes that can provide faster and higher realtime performance than the RLC acknowledged data transfer mode. It is considered to be indispensable to collect traffic corresponding to the total amount of communication data during the data delivery using operation modes other than the RLC acknowledged data transfer mode.
It is therefore an object of the present invention to provide a radio communication system and a repeating apparatus that can realize a data delivery service in another operation mode to ensure faster and higher realtime performance than an operation mode capable of exchanging delivery acknowledgment information using the link protocol layer, collect the total amount of data delivered by the data delivery service, and realize a charging process based on the total amount of data.
The present invention provides a radio communication system comprising a mobile station, a base station, and a radio communication controller. The base station comprises: radio communication means for making radio communication with the mobile station; response signal reception means for interacting with signal transmission to the mobile station and receiving a response signal returned from the mobile station; collection means for, when a signal is transmitted to the mobile station and then a response signal returned from the mobile station is received, collecting the amount of signal transmitted to the mobile station; and controller interface means for making signal communication with the radio communication controller and transmitting the amount of signal collected by the collection means to the radio communication controller.
According to the present invention, the base station collects the amount of signal based on a response signal from the mobile station. That is to say, the present invention does not aim at collecting the amount of data during data delivery conditioned on delivery acknowledgment in a higher layer like the link protocol layer using the RLC acknowledged data transfer mode in a third generation cellular phone system, for example. The present invention collects the amount of data in the base station, i.e., a lower layer such as the physical layer.
According to the present invention, the base station collects the amount of signal based on a response signal from the mobile station. The present invention can therefore realize a data delivery service in an operation mode to ensure faster and higher realtime performance than the operation mode capable of exchanging delivery acknowledgment information using the link protocol layer in the third generation cellular phone system, for example. At the same time, it is possible to collect the total amount of data delivered by the data delivery service. Consequently, the present invention also makes it possible to realize a charging process based on the total amount of collected signals.
The embodiment of the present invention describes a radio communication system (radio network system) and a repeating apparatus (base station) according to the present invention. As an example, the description presents the HSDPA (high speed downlink packet access) system in R5 (release 5) of 3GPP (3rd generation partnership project) that is a standardization project for the third generation cellular phone system.
An R5 HSDPA service assumes the use of RLC unacknowledged data transfer mode (unacknowledge mode: UM) for the delivery service of video streaming data and the like. If the data delivery can be realized by using the RLC UM, it is possible to minimize a delay between apparatuses in the network due to retransmission of RLC in the RLC acknowledged data transfer mode (AM), for example. It is considered to be able to provide data delivery services with the high realtime performance. The embodiment adopts a packet switching service using the RLC UM compliant with the R5 HSDPA. Consequently, it is possible to realize a data delivery service having faster (higher-throughput) and higher realtime performance than the conventional operation mode capable of exchanging delivery acknowledgment information using the link protocol layer.
The RLC UM for the unacknowledged link protocol layer is one of protocol modes applicable to packet switching services and is presently used only for non-traffic data bearers. Starting a packet switching data delivery service using the RLC UM requires a system configuration to charge data to be exchanged in the RLC UM. For this reason, the embodiment according to the present invention uses the configuration (to be described later) to realize packet switched charging for data exchanged in the RLC UM, i.e., charging corresponding to the amount of data exchanged. The RLC UM exchanges data in both directions upstream and downstream. Charging only downstream data counts the number of packets of data whose delivery is acknowledged by mobile stations.
In order to ensure data transfer acknowledgment between the mobile station and the base station, the R5 HSDPA uses a hybrid automatic repeat request (HARQ) in the physical layer to exchange ACK (acknowledge) or NACK (non-acknowledge) information. Accordingly, the embodiment allows an R5 HSDPA service compliant with 3GPP to use the ACK/NACK information for HARQ in the physical layer and enables traffic collection in the RLC unacknowledged data transfer mode (RLC UM) which is unavailable in R99 (release 99).
The following describes operations of the radio network system according to the embodiment of the present invention with reference to the accompanying drawings.
At step S1, the radio network system according to the embodiment performs a process for position registration between a mobile station (UE), a base station (Node-B) functioning as a repeating apparatus, and a base station controller (radio network controller: RNC) functioning as a radio communication controller. At step S2, the radio network system performs a process to establish a DCCH (dedicated control channel) for an SRB (signaling radio bearer). If the SRB DCCH establishment (control signal bearer establishment) is complete at step S2, the radio network system performs a process to establish a radio bearer (RAB) for an HS-DSCH (high speed-downlink shared channel) at step S3. During the HSDPA radio bearer establishment at step S3, the base station controller (RNC) determines an RLC operation mode for the HSDPA RAB. The position registration at step S1, the control signal bearer establishment at step S2, and the HSDPA radio bearer establishment comply with the 3GPP call establishment sequence. The detailed description about these processes is omitted here for simplicity.
Upon completion of the processes at steps S1 through S3, the radio network system according to the embodiment starts a traffic collection process at step S4.
When control proceeds to the traffic collection process at step S4, the base station controller sends a start request (Traffic Collection Start Request) to the base station at step S10. That is to say, the start request is configured to be a control signal (traffic collection start request control signal) for the base station controller to notify the base station with various information elements used in the traffic collection process. During the start request (Traffic Collection Start Request), the base station controller sends the following parameters to the base station as shown in
When receiving the above-mentioned start request, the base station, at step S11, generates and initializes a traffic management table to collect and manage traffic in units of mobile stations. Traffic needs to be collected in units of mobile stations. For this reason, the base station according to the embodiment identifies the mobile station ID. Based on the mobile station ID, the base station creates and manages the traffic management table so as to collect and manage traffic in units of mobile stations. Specifically, the R5 system to which the embodiment is applied provides an H-RNTI for each user (i.e., each mobile station) to receive HSDPA compliant data delivery services. The base station provides the traffic management table to collect and manage the traffic in units of H-RNTI for each mobile station. The base station manages information to be stored in the traffic management table.
Now back to
At step S13, the base station sends a start response (Traffic Collection Start Response) to the base station controller. At step S14, the base station determines the CFN. When the CFN reaches Activation_Time for the HSDPA RAB (CFN=Activation_Time), the base station starts the traffic collection process at step S15. At the time of the start response (Traffic Collection Start Response), the base station sends H-RNTI, Measurement-ID identifying the traffic collection process, and RESULT indicating a start result to the base station controller as shown in
At step S5, the radio network system according to the embodiment starts transferring HSDPA data downstream almost simultaneously with the traffic collection start process in the base station. At step S16 instep S5, the system transfers HSDPA data downstream (HSDPA Data Transfer). At step S17, the mobile station sends delivery acknowledgment information (response signal ACK) to the base station. At step S18, the base station receives the delivery acknowledgment information to collect the traffic.
At step S6, the radio network system according to the embodiment stops collecting the traffic. The process to stop the traffic collection at step S6 is performed when a call disconnection occurs at step S19, when handover occurs in an HS-DSCH, or when there occurs a process to stop the charging process (e.g., MAC reset process). When receiving a trigger to stop the charging process such as the call disconnection request or the handover, the base station controller issues a traffic collection request (Traffic Collection Report Request) to the base station at step S20. At the time of the traffic collection request (Traffic Collection Report Request), the base station controller sends H-RNTI and Measurement-ID to the base station as shown in
When receiving the traffic collection request, the base station creates a traffic collection report at step S21. The traffic collection report contains Acked_Data_Sum up to the time when the traffic collection request was issued and also contains the Duration information indicating the traffic collection execution time. At step S22, the base station sends the traffic collection report to the base station controller (Traffic Collection Report). At the time of Traffic Collection Report, the base station sends H-RNTI, Measurement-ID, and the Duration information and Acked_Data_Sum contained in the traffic collection report to the base station controller as shown in
When receiving the traffic collection report, the base station controller sends Traffic Collection Stop Request to the base station at step S23. At the time of Traffic Collection Stop Request, the base station controller sends H-RNTI and Measurement-ID to the base station as shown in
When receiving the traffic collection stop request, the base station stops collecting the traffic at step S24. Then, at step S25, the base station returns Traffic Collection Stop Response to the base station controller. At the time of Traffic Collection Stop Response, the base station sends H-RNTI, Measurement-ID, and RESULT showing a stop result to the base station controller as shown in
Thereafter, the base station controller transfers the traffic collection report to a charging apparatus (not shown) that charges users.
There has been described the flow of data delivery and traffic collection in the radio network system according to the embodiment of the present invention. The following describes detailed flows of the data delivery and the traffic collection process.
With reference to
Though not shown in the sequences of
In process P1 of
In process P2 of
In process P4 of
When receiving the MAC-HS PDU from the base station, the mobile station issues HARQ delivery acknowledgment (ACK) in units of MAC-HS PDUs at step S38 of
In process P6 of
At step S38, the base station receives the delivery acknowledgment ACK from the mobile station. The base station then extracts the number of MAC-D PDUs multiplexed in the delivery-acknowledged MAC-HS PDU based on the above-mentioned N's value in the traffic management table. At step S39, the base station calculates Acked_Data_Sum according to equation (1) below and records the calculated value in the traffic management table. The sum of higher layer data is unnecessary for a mobile station user as an end user. For this reason, the base station calculates Acked_Data_Sum by excluding link layer headers that are attached between apparatuses in the network.
Acked—Data—Sum={(N1*Size—1)+(N2*Size—2)+ . . . +(Nn*Size—n)}−{(N*(RLC—HEADER+MAC—HEADER)} (1)
In equation (1), Size_n indicates the MAC-D PDU size. RLC_HEADER and MAC_HEADER in equation (1) are link layer headers and have fixed lengths. This parameter is notified to the base station by means of the above-mentioned traffic collection start request control signal. In operation, the MAC-D PDU size is equivalent to RLC UMD PDU and is given Semi-Static Attributes to be free from changing for each TTI.
Accordingly, Acked_Data_Sum can be also calculated using equation (2) below.
Acked—Data—Sum=N*{Size—1 or Size—2−(RLC—HEADER+MAC—HEADER)} (2)
Equation (2) expresses increasing the total number of bytes multiplexed to the TSN each time the delivery acknowledgment is received from the mobile station. As a result, this is equivalent to acquisition of the total number of downstream packets (i.e., Acked_Data_Sum) for a specified user (mobile station) during communication.
In this manner, there have been completed the data delivery of PDU A from the radio access network to the mobile station and the traffic collection process for the data delivery.
In process P1 of
In process P2 of
In process P4 of
When receiving the MAC-HS PDU from the base station, the mobile station issues HARQ delivery acknowledgment in units of MAC-HS PDUs at step S56. In process P6 of
At step S56, the base station receives the delivery acknowledgment from the mobile station. The base station then extracts the number of MAC-D PDUs multiplexed in the delivery-acknowledged MAC-HS PDU based on the above-mentioned N's value in the traffic management table. At step S57, the base station calculates Acked_Data_Sum according to equation (1) or (2) as mentioned above and records the calculated value in the traffic management table.
In this manner, there have been completed the data delivery of PDU B from the radio access network to the mobile station and the traffic collection process for the data delivery.
At step S101 of
At step S103, the base station extracts the TSN from downstream HSDPA transfer data based on the ACK/NACK delivery reception timing information for HS-DPCCH. At step S104, the base station updates VT (A) and VT (TSN) out of the Priority_Queue based state variables. At step S105, the base station updates the Acked_Data_Sum variable.
At step S106, the base station determines whether or not to receive a traffic collection stop request. If that request is not received, the base station returns process to step S101. If the request is received, the base station terminates the traffic collection process.
First, the following describes the flowchart in
At step S111 of
At step S114, the base station controller sends a traffic collection report provided with the H-RNTI or Measurement-ID to the base station. At step S115, the base station controller awaits the traffic collection report. At step S116, the base station controller receives the traffic collection report. At step S117, the base station controller sends the traffic collection report to the charging apparatus.
After sending the traffic collection report, the base station controller, at step S118, sends the above-mentioned Traffic Collection Stop Request to the base station. Further at step S118, the base station controller deletes the respective data after sending the Traffic Collection Stop Request.
For example, there may be a case where a handover occurs to change the base station. In such case, traffic is collected by base stations before and after the change due to the handover. The radio network system according to the embodiment is configured to send this traffic to the charging apparatus via the radio network controller. The charging apparatus totals the traffic collected by the base stations before and after the change due to the handover. At this time, the charging apparatus specifies a mobile station associated with the handover. Even if handover occurs to change the base station, the radio network system according to the embodiment can charge a user of the mobile station associated with the handover.
The following describes the flowchart in
At step S121 of
At step S124, the base station receives the traffic collection stop request from the base station controller. At step S125, the base station stops collecting the traffic corresponding to the Measurement-ID. Thereafter, the base station deletes the respective data.
In
The base station body 20 comprises: a transmission power amplification section 21; a radio section 22; a baseband signal processing section 23; a wired transmission path interface section 24; a control section 25; an HARQ ACK/NACK reception function section 26; and a conversion table 27. In addition to this configuration, the base station body 20 further comprises: a traffic collection processing section 28; a traffic management table 29; and a buffer (storage means) 30 as a configuration for traffic collection according to the embodiment. The conversion table 27, the traffic collection processing section 28, and the buffer 30 may be included as a function section in the control section 25.
The wired transmission path interface section 24 interfaces the base station controller with the base station. The wired transmission path interface section 24 has the ATM (asynchronous transfer mode) processing function, the AAL (ATM adaptation layer) signal processing function, the service specific connection oriented protocol (SSCOP) function, and the like.
The baseband signal processing section 23 performs processes such as error correction coding, framing, data modulation, spread modulation, and the like for transmission signals supplied via the wired transmission path interface section 24. The baseband signal processing section 23 then transmits the processed signal to the radio section 22. Further, the baseband signal processing section 23 performs signal processes such as despreading, chip synchronization, error correction coding, data multiplexing/demultiplexing, maximum ratio combining for diversity handover between sectors, and the like for reception signals that are received by the antenna 11 and are supplied via the radio section 22.
The radio section 22 digital/analog converts a baseband spread signal, converts the signal into a radio frequency signal using orthogonal transformation, and transmits the signal to the transmission power amplification section 21. Further, The radio section 22 quasi-coherently detects a reception signal that is received by the antenna 11 and is supplied via the outdoor reception amplifier 12 and the like. The radio section 22 analog/digital converts the signal and transmits it to the baseband signal processing section 23.
The transmission power amplification section 21 amplifies the power of a transmission signal from the radio section 22 up to a required antenna input level.
The control section 25 provides control over sending or receiving call control signals from the base station controller, managing radio lines, establishing or releasing radio lines, and performing the traffic collection according to the embodiment.
The HARQ ACK/NACK reception function section 26 receives ACK/NACK information according to the above-mentioned HARQ and manages ACK/NACK delivery reception timings.
As mentioned above, the traffic collection processing section 28 is a function section to perform overall processes for the traffic collection in the base station according to the embodiment.
The conversion table 27 is used to convert the above-mentioned channelization code used for HS-DPCCH into H-RNTI.
The buffer 30 buffers UMD-PDUs, MAC-D PDU, or MAC-HS transmission unit the HARQ delivery acknowledgment (ACK) is received from the mobile station.
As mentioned above, the radio network system according to the embodiment of the present invention uses the RLC unacknowledged data transfer mode such as the R5 HSDPA compliant RLC UM to enable delivery of realtime critical data such as video streaming data. Further, the radio network system can collect traffic in packet switching services using the R5 HSDPA compliant RLC UM.
The above-mentioned embodiment is an example of the present invention. The present invention is not limited to the above-mentioned embodiment. It is further understood by those skilled in the art that various changes and modifications may be made in the present invention depending on designs and the like without departing from the technical concept and scope thereof. For example, the present invention is not limited to R5 HSDPA systems compliant with 3GPP. Further, the radio network system is not limited to cellular phone systems. The base station according to the present invention is not limited to base stations for the cellular phone systems. For example, the present invention is also applicable to repeating apparatuses for various radio network systems provided with modes equivalent to the above-mentioned RLC unacknowledged data transfer mode. Moreover, the present invention is also applicable to data deliveries that are independent of requests from users. Furthermore, traffic may be collected based on not only the number of packets, but also the communication time.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2003-293731 | Aug 2003 | JP | national |
