CN1728881A - The method that control data sends - Google Patents

Abstract

The method that a kind of control data sends, method comprises step: RNC obtains propagation delay time and the time difference between itself and each base station; The common signal channel of RNC allocating cell and transmission data; RNC controls the time started that each sub-district sends data; RNC tells the frame shifting amount and the chip side-play amount of subscriber equipment Common transport channel by the Uu interface; Subscriber equipment receives from the configuration of common channel parameter of RNC transmission.The present invention has realized that the signal of the common signal channel of different districts merges, and the signal quality that makes subscriber equipment receive is better, and the throughput of system is bigger.

Description

The method that control data sends

Technical field

The present invention relates to 3G (Third Generation) Moblie, particularly a kind of method that multimedia broadcast-multicast service is provided.

Background technology

Multimedia broadcast-multicast service (hereinafter to be referred as MBMS) is a new business that defines in 3-G (Generation Three mobile communication system) partner program 3GPP.With broadcasting or the business utilization that provides of multicast mode is that unidirectional point is to multipoint system (promptly broadcast out multi-medium data from single data source and be sent to a plurality of users' receptions through Network Transmission).The maximum characteristics of this mode are that it can effectively utilize Radio Resource and Internet resources.The MBMS business is mainly used in the wireless communication network system, as Wideband Code Division Multiple Access (WCDMA) communication system WCDMA, global system for mobile communications GSM etc.The transmission of business datum will be passed through basically among the MBMS: transmission in data source transmission, go-between transmission, the purpose cell null, user receive such plurality of processes.Fig. 1 is a wireless communication system logical network equipment drawing that the MBMS business can be provided, and in fact MBMS has utilized general grouped wireless data service (hereinafter to be referred as GPRS) network as core transport network in the figure.As shown in Figure 1, broadcasting and multicast service center 70 (hereinafter to be referred as BM-SC) are the data sources that sends the MBMS business datum; Gateway GPRS Support Node 60 (hereinafter to be referred as GGSN) is used for being connected of GRPS network and external network (as the INTERNET network); Gateway GPRS Support Node connects BM-SC and the MBMS data is sent to specific Serving GPRS Support Node 50 (hereinafter to be referred as SGSN) in the MBMS business; SGSN is used for UE is carried out access control and mobile management, the MBMS data of coming from GGSN is sent to the specific radio-cell controller 30 (hereinafter to be referred as RNC) go simultaneously; RNC is used for controlling one group of base station 23 and 24 and multi-medium data is sent to specific base stations 23 and 24; Aerial common signal channel 11 is set up for the MBMS business of sub-district 21 in base station 23 under the control of RNC; Aerial common signal channel 12 is set up for the MBMS business of sub-district 22 in base station 24 under the control of RNC; Subscriber terminal equipment 10 (hereinafter to be referred as UE) is the terminal equipment that receives the MBMS data.

When between subscriber equipment and network, carrying out point-to-point communication; network can be set up dedicated channel to subscriber equipment usually; by what this subscriber equipment exclusively enjoyed, other Any user equipment can not use these Radio Resources to the shared Radio Resource of this channel in communication process.And when network provides the MBMS business, in order effectively to utilize Radio Resource and Internet resources, aloft be to adopt between common signal channel and a plurality of subscriber equipmenies to communicate by letter simultaneously on the interface.A plurality of subscriber equipmenies can receive wireless signal from network simultaneously after the resource distribution that obtains this common signal channel, thereby obtain the MBMS business.It is not support soft handover that but common signal channel is different from an obvious characteristic of dedicated channel.The meaning of soft handover is that the user can merge processing with signal then simultaneously from a plurality of sub-districts received signal, thereby obtains signal quality and lower data loss rate preferably.As the subscriber equipment among Fig. 1 10, if network 21 and 22 has all been set up transmission channel for it in the sub-district, subscriber equipment 10 can receive simultaneously from the sub-district 21 and 22 signal so, and prerequisite is that these two sub-districts are neighbor cells.

In order to support soft handover, the signal that the physical layer of subscriber equipment receives must satisfy certain delay requirement, and for example in present WCDMA system, delay requirement must be within positive and negative 148chip, promptly within 0.03854 millisecond.And the satisfied of this condition is to be finished by the Serving RNC control of subscriber equipment, referring to Fig. 2.Sub-district 1 is 21 among Fig. 1, and sub-district 2 is 22 among Fig. 1.The 201st, the timing relationship relevant, the 202nd, the timing relationship relevant with sub-district 22 with sub-district 21.Introduce the implication of each clock of definition in the WCDMA system below earlier:

The frame number of BFN:Node B, 10 milliseconds of each frame lengths, from 0 to 4095 circulation of frame number.

The System Frame Number of the sub-district of SFN:Node B control, 10 milliseconds of each frame lengths, from 0 to 4095 circulation of frame number.SFN and BFN differ the length of a Tcell in time, and Tcell value from 0 to 9, granularity are 256chip (being about 1/15 millisecond), and promptly the value of Tcell is 0,2/15,3/15,4/15,5/15,6/15,7/15,8/15,9/15, and unit is a millisecond.

CFN: the channel type that receives with subscriber equipment has relation, if common signal channel, then be SFN to 256 deliverys, if dedicated channel, then deduct behind the frame shifting amount 256 deliverys for SFN.CFN1 among Fig. 2 and CFN2 are at common signal channel, and CFN1 ' and CFN2 ' are at dedicated channel.Only in 201, the frame shifting amount of dedicated channel is 0, and the frame shifting amount of special-purpose channel is 6 in 202.In real system, no matter be dedicated channel or common signal channel, may there be the time difference on the chip rank in the frame starting point of their frame starting point and SFN, and this time difference all is on 0 to 149 256chip.For simplicity, in Fig. 2, we suppose that the chip side-play amount of two sub-districts 21 of dedicated channel and 22 is Dcoff, and the chip side-play amount of common signal channel in two sub-districts 21 and 22 is Soff.

Because WCDMA system neither one carries out the equipment that clock is adjusted for the all-network unit, GPS for example is so the clock of each network equipment might be different.And deviation also might take place in the frequency of each clock.RNC has the clock of oneself to carry out time control, and Node B also has the clock of oneself to carry out time control.But because any resource distribution of Node B is all controlled by RNC, the time that data send is also grasped by RNC, therefore is necessary to allow RNC that the clock characteristic at NodeB place is known a little.What Fig. 3 described is to carry out the synchronous method of node between RNC and the Node B.The clock of RNC is represented that by RFN RFN is the frame number of RNC side, 10 milliseconds of each frame lengths, from 0 to 4095 circulation of frame number.Time in a circulation can be expressed as 0 to 40959.875, and granularity is 0.125 millisecond, is equivalent to the length of 480chip.RNC sends the descendant node synchronization message for Node B, comprises the time t1 that sends to this message in the message, after Node B receives this message, the moment t2 of this message received in record, Node B sends the upstream node synchronization message to RNC then, comprises t1 in this message, t2 and t3.Wherein t3 is the time that Node B sends the upstream node synchronization message.After RNC received this message, record received that its time is t4.So far carrying out the synchronous process of node between RNC and the Node B finishes.RNC is according to t1, t2, and four parameters of t3 and t4 can calculate the time delay of transfer of data between RNC and the NodeB, and can know the corresponding relation of time and the Node B time of RNC.The time delay that we define between RNC and the Node B is RTD, RTD=(t4-t1-t3+t2)/2.The corresponding time relationship of the time of RNC and Node B is: time+t2-t1-RTD of time=RNC of NodeB.Certainly in the actual transmissions process, should consider the variation of RTD and RTD, because the propagation delay time on Iub interface may be relevant with the actual conditions of transmission network at that time.

According to top equation, if we suppose the substantially invariable words of propagation delay time between RNC and the Node B, RNC can clearly know the time of Node B so, and the granularity of this time is 0.125 millisecond certainly, i.e. 480chip.

The time that RNC has known Node B, it controlled the transmitting time of common signal channel with will be clear that not enough.The transmitting time of common signal channel should be BFN+Tcell+Soff according to shown in Figure 2.In order to guarantee that time delay that different districts sends data less than desired value, must meet the following conditions: absolute value ((BFN1+Tcell1+Soff1)-(BFN2+Tcell2+Soff2))＜desired time delay so.

In the WCDMA system, it not is can from any one frame that the transmission of a new data begins.Defined a Transmission Time Interval TTI at each transmission channel in the WCDMA system, the value of this TTI is the integral multiple of frame length, for example 10 milliseconds, and 20 milliseconds, 40 milliseconds or 80 milliseconds.The number of the frame that pairing each TTI is shared is 1,2,4 and 8.Can only occur in CFN the zero hour of these TTI is moment of 0 to the Fn delivery, and Fn is the number of the frame of TTI correspondence.On this basis, RNC also to control sub-district or configuration of common channel parameter and moment of making data that subscriber equipment received in a TTI, begin identical.Therefore formula should be revised and become: absolute value (((BFN1+Tcell1+Soff1)-(BFN2+Tcell2+Soff2)) mould Fn)＜desired time delay.

Because the length of Tcell and Soff maximum is respectively 9/15 millisecond and 10 milliseconds, no matter how to adjust, all can not be under the diverse situation of the BFN of two sub-districts, make in data delay missionary society that subscriber equipment receives from two sub-districts less than 10 milliseconds by adjusting Tcell and Soff.And 10 milliseconds in general, all be to carry out delay requirement that signal merges greater than subscriber equipment.In MBMS, we come transmitting user data with common signal channel.Residing all positions can both receive signal in the sub-district in order to allow all users, and the transmitting power of needed common signal channel will be bigger, does the interference that can cause usually neighbor cell like this, reduce the capacity of system.Therefore a kind of mode that the common channel signal of different districts is merged proposes, but this just requires the signal front and back time delay of the same common signal channel of neighbor cell emission can not surpass certain numerical value, otherwise just can not reach the purpose of combined signal, the optimization quality of reception.But the signal front and back time delay that not can guarantee the same common signal channel that neighbor cell is launched in the current system is in relative small range.

Summary of the invention

The purpose of this invention is to provide the method that a kind of control data sends, be intended to guarantee before and after the signal of same common signal channel of neighbor cell emission that time delay in small range relatively, becomes possibility thereby make subscriber equipment merge the signal that receives from a plurality of sub-districts.

For achieving the above object, the method that a kind of control data sends, method comprises step:

RNC obtains propagation delay time and the time difference between itself and each base station;

The common signal channel of RNC allocating cell and transmission data;

RNC controls the time started that each sub-district sends data;

RNC tells the frame shifting amount and the chip side-play amount of subscriber equipment Common transport channel by the Uu interface;

Subscriber equipment receives from the configuration of common channel parameter of RNC transmission.

The present invention has realized that the signal of the common signal channel of different districts merges, and the signal quality that makes subscriber equipment receive is better, and the throughput of system is bigger.

Description of drawings

Fig. 1 is MBMS logical device figure;

Fig. 2 is a clock timing diagram;

Fig. 3 is RNC and Node B timing sequence diagram;

Fig. 4 is a block diagram of the present invention;

Fig. 5 is clock definition of the present invention;

Fig. 6 is the timing relationship of user equipment side of the present invention;

Fig. 7 is a first embodiment of the invention;

Fig. 8 is a second embodiment of the invention;

Fig. 9 is a third embodiment of the invention;

Figure 10 is the sequential chart of first embodiment of the invention;

The action behavior of Figure 11: UE;

The action behavior of Figure 12: RNC;

Figure 13: the action behavior of Node B.

Embodiment

It is smaller for the time difference that same piece of data sends that RNC will control different districts, and for example less than 5 milliseconds, RNC at first will draw the time difference 401 between each Node B so.The realization of this function can utilize flow chart among Fig. 3 and obtain, and 431 among Fig. 4 is exactly the flow chart in the application drawing 3.After RNC finishes the node synchronizing process with Node B23 and 24 respectively, promptly carry out Signalling exchange according to Fig. 3 between 411 and 412, RNC just can know the difference of BFN: BFN1-BFN2=(t2-1-t1-1-RTD1)-(t2-2-t1-2-RTD2) between the Node B23 and 24 of its control.This time difference is in existing system on 0.125 millisecond granularity.Concrete algorithm can be because of the difference of specific implementation difference to some extent.

401 finish after, RNC will determine that each sub-district sends the concrete time 402 of data.In different embodiment, the Tcell parameter of RNC or allocating cell or configuration Soff parameter or dispose Tcell simultaneously and the Soff parameter.The scope of these two parameters all will enlarge on original basis.For the ease of understanding, we resolve into two parameters with the Tcell that enlarges, a parameter is Tcell, the effect and the scope that define in this parameter and the existing system all are the same, the another one parameter is Coff, and the SFN of each sub-district is with respect to the difference of BFN among this parametric representation different N ode B.The Soff that enlarges is the time offset in a frame that common signal channel is directed to SFN, for the ease of understanding, we resolve into two parameters with the Soff that enlarges, a parameter is Soff, the effect and the scope that define in this parameter and the existing system all are the same, the another one parameter is CHoff, and the CFN of the different MBMS transmission channels of this parametric representation is with respect to the frame shifting amount of cell SFN.Fig. 5 has provided the definition of these four parameters.As can be seen from Figure 5, time of representing of time-Tcell of representing of time-Coff of representing of the moment=BFN of beginning of SFN.The time that time-Soff that time-CHoff that the moment=SFN that common signal channel CFN begins represents represents represents.By such computing formula, after these four parameters were told Node B by Iub signaling 432, Node B just can correspondingly calculate the time started that sends data.

RNC tells the frame shifting amount and the chip side-play amount of subscriber equipment Common transport channel by the signaling of 441Uu interface.Subscriber equipment obtains SFN by reading system information of subdistricts, knows that by the computing formula of CFN the data in the TTI from which frame, from which chip begin.CFN＝(SFN-Choff)mod?256。TTI to begin to satisfying CFN mod Fn be 0 frame.Fn represents that TTI has several frame lengths.

Also have a kind of method by only adjusting the method for subscriber devices compute TTI start frame, reach desired delay requirement.By the description of front as can be known, the method for calculating the TTI start frame is that to satisfy CFNmodFn be 0 frame.Fn represents that TTI has several frame lengths.Because from the CFN of the common signal channel of different cell transmission all is different, know the zero hour of transmission TTI in order to make subscriber equipment, be the value of a CFNoff of the common signal channel of each MBMS transmission data transmission, by this value, subscriber equipment can be adjusted the zero hour of TTI.As shown in Figure 6.In sub-district 22, subscriber equipment receives and does not just satisfy top formula the zero hour of a TTI of data, and should consider a side-play amount.In this example, the length of TTI is 40 milliseconds, i.e. the beginning of TTI should equal 0 place at CFN mould 4 and begin.Value for the CFN side-play amount in the sub-district 21 is 0, and the CFN side-play amount in the sub-district 22 is 3.

That Fig. 7 describes is first embodiment of the present invention.

This embodiment realizes by the frame shifting amount that changes different districts.701 and 702 by the RNC of Fig. 3 description and the synchronizing process of Node B, obtains the propagation delay time of Iub interface and the time difference between RNC and the Node B.When RNC collect between it and a plurality of Node B propagation delay time and after the time difference, RNC will calculate the down frame shifting amount of the sub-district of configuration of different Node B, thus make all sub-districts equal the time difference of 0 frame within necessary time delay scope at SFN mould Fn.One of Calculation Method can be got a NodeB as a reference, and other NodeB carry out under the situation that this NodeB dresses.As shown in figure 10.SFN among Figure 10 and the time relationship of BFN are: the time of time-Tcell of time-Coff of time=BFN1 of SFN1.Wherein the time of Coff is 0.The time of time-Tcell2 of time-Coff2 of time=BFN2 of SFN2, wherein Coff2 is 3 frames.As seen in Figure 10, the SFN of two sub-districts front and back under the situation of Fn=4 differ the length that is no more than a frame.

Behind the Coff and Tcell of RNC, just in 703 and 704 processes, Coff and Tcell parameter are passed to Node B according to each sub-district of above-mentioned algorithm configuration.Node B according to these two parameters can allocating cell 705 launch time and on broadcast channel the SFN of broadcast cell.In the method for setting up common signal channel in 706 and 707 and the prior art is the same.RNC sends to Node B with the relevant configuration of common signal channel, sets up its common signal channel, and the transmitting time of this common signal channel has the deviation of Soff.This Soff is the reference value the same with prior art.

That Fig. 8 describes is second embodiment of the present invention.This embodiment realizes by the frame shifting amount that changes the different districts common signal channel.801 and 802 by the RNC of Fig. 3 description and the synchronizing process of Node B, obtains the propagation delay time of Iub interface and the time difference between RNC and the Node B.803 and 804RNC be offset Tcell according to the emission of existing each Node B of arrangements sub-district down.805 stage Node B are according to the emission skew of the configuration parameter allocating cell of the transmission of RNC.When RNC will set up common signal channel for the transmission data, send 806 to Node B and set up common signal channel, the vertical shift of common signal channel and chip side-play amount are specified by CHoff and Soff.Node B is according to the launch time of these two parameter configuration common signal channels.RNC sends to subscriber equipment with the parameter of common signal channel by the RRC signaling after network side is set up successful common signal channel.Subscriber equipment obtains the configuration of common channel parameter by 808, and this common signal channel frame shifting amount and chip side-play amount, calculates the time started that receives data.During the CFN of this common signal channel of subscriber devices compute, pass through formula: CFN=(SFN-CHoff) mod 256 and calculate.Will satisfy the frame number of CFNmod Fn=0 the zero hour of TTI.Subscriber equipment not only obtains the configuration of common channel of current area, and the user that can also obtain adjacent cell provides the Choff parameter of configuration of common channel, the especially common signal channel of MBMS business.When subscriber equipment when cell edge can receive a plurality of cell signal simultaneously, subscriber equipment just can be according to the configuration of common channel of a plurality of sub-districts, received signal from the common signal channel of a plurality of sub-districts, and it is merged.

That Fig. 9 describes is the 3rd embodiment of the present invention.

This embodiment is that the vertical shift by the beginning of configure user equipment side TTI realizes.901 to 907 is all identical with realization of the prior art, also can realize with the relevant signaling process among the Tu with reference to Fig. 7.After network side configuration complete primary school district and configuration of common channel, 908RNC informs the frame shifting amount of the beginning of subscriber equipment TTI.Subscriber equipment is determined the common signal channel TTI zero hour according to this side-play amount.The method of determining is: (CFN-CFNoff) frame of mod Fn=0 constantly.Subscriber equipment not only obtains the configuration of common channel of current area, and the user that can also obtain adjacent cell provides the configuration of common channel of MBMS business, especially at the frame shifting amount of the beginning of the TTI of common signal channel.When subscriber equipment when cell edge can receive a plurality of cell signal simultaneously, subscriber equipment just can be according to the configuration of common channel of a plurality of sub-districts, adjust the vertical shift that different districts common signal channel TTI begins, received signal from the common signal channel of a plurality of sub-districts, and it is merged.

What Figure 11 described is the action behavior of UE of the present invention.

UE is before beginning to receive the MBMS data, monitor the common signal channel that on multicast control channel MCCH, sends and set up message (name of this message can be other) 1101, can comprise the configuration parameter of the physical layer of this common signal channel and transport layer and Fig. 8 of the present invention in this message 808 and describe the TTI frame shifting amount of describing among common signal channel frame shifting amount Choff among the embodiment or Fig. 9 of the present invention.1102 users are according to these two parameters, dispose the time that the TTI of common signal channel begins accordingly.If parameter is Choff, CFN=(SFN-CHoff) mod 256 calculates so.If will satisfy the frame number of CFNmod Fn=0 the zero hour of TTI. parameter is CFNoff, will satisfy the frame moment of (CFN-CFNoff) mod Fn=0 so the zero hour of TTI.

What Figure 12 described is the action behavior of RNC of the present invention.

The RNC decision provides the MBMS data service and calculates after the common signal channel frame shifting amount Choff of each Node B on common signal channel, RNC sends common signal channel for Node B and sets up message (name of this message can be other) 1201, can may comprise the configuration parameter of the physical layer of this common signal channel and transport layer and Fig. 8 of the present invention in this message 806 and describe common signal channel frame shifting amount Choff among the embodiment.When RNC receives after the response that Node B returns 1202, check whether this response is success response, if, so just send common signal channel and set up message 1203, can comprise the configuration parameter of the physical layer of this common signal channel and transport layer and Fig. 8 of the present invention in this message and describe the 908 TTI frame shifting amounts of describing among common signal channel frame shifting amount Choff among the embodiment or Fig. 9 of the present invention to subscriber equipment.Otherwise then the MBMS business can not be set up successfully on common signal channel.

What Figure 13 described is the action behavior of Node B of the present invention.

Node B receives the common signal channel that RNC sends and sets up message (name of this message can be other) 1301, can comprise the configuration parameter of the physical layer of this common signal channel and transport layer and Fig. 8 of the present invention in this message 806 and describe the time that the common signal channel frame shifting amount Choff.1302Node B among the embodiment begins according to the TTI of this parameter configuration common signal channel.CFN=(SFN-CHoff) mod 256 is satisfied in the calculating of CFN.Will satisfy the frame number of CFNmod Fn=0 the zero hour of TTI.

Claims (6)

1. the method that sends of a control data, method comprises step:

RNC obtains propagation delay time and the time difference between itself and each base station;

RNC is by the frame shifting amount of Iub interface allocating cell System Frame Number with respect to the frame number of the base station under this sub-district;

The RNC configuration sends the common signal channel of data;

Node B receives from the cell configuration parameter and the common signal channel configuration parameter of RNC transmission; RNC tells subscriber equipment Common transport channel configuration parameter by the Uu interface;

Subscriber equipment receives from the configuration of common channel parameter of RNC transmission.

2. the method that sends of a control data, method comprises step:

RNC obtains propagation delay time and the time difference between itself and each base station;

RNC is by the Iub interface allocating cell;

RNC sends the common signal channel of data and Connection Frame Number thereof the frame shifting amount with respect to the System Frame Number of this sub-district by Iub interface configuration;

Node B receives from the cell configuration parameter and the common signal channel configuration parameter of RNC transmission;

RNC tells subscriber equipment Common transport channel configuration parameter by the Uu interface;

Subscriber equipment receives from the configuration of common channel parameter of RNC transmission.

3. method according to claim 2 is characterized in that RNC can tell subscriber equipment with the frame shifting amount of the common signal channel of adjacent cell or the parameter zero hour of TTI on the channel of this sub-district.

4. the method that sends of a control data, method comprises step:

RNC obtains propagation delay time and the time difference between itself and each base station;

RNC is by the Iub interface allocating cell;

RNC sends the common signal channel of data by the Iub interface configuration;

Node B receives from the cell configuration parameter and the common signal channel configuration parameter of RNC transmission;

RNC tells the frame shifting amount of the zero hour of subscriber equipment Common transport channel signal by the Uu interface;

Subscriber equipment receives from the frame shifting amount of the zero hour of the configuration of common channel parameter of RNC transmission and Common transport channel signal.

5. method according to claim 4 is characterized in that RNC can tell subscriber equipment with the frame shifting amount of the common signal channel of adjacent cell or the parameter zero hour of TTI on the channel of this sub-district.

6. the method that sends of a control data, method comprises step:

RNC obtains propagation delay time and the time difference between itself and each base station;

RNC is by the frame shifting amount of Iub interface allocating cell system frame number with respect to the frame number of the base station under this sub-district;

RNC sends the common signal channel of data and Connection Frame Number thereof the frame shifting amount with respect to the System Frame Number of this sub-district by Iub interface configuration;

Node B receives from the cell configuration parameter and the common signal channel configuration parameter of RNC transmission;

RNC tells the subscriber equipment Common transport channel by the Uu interface;

Subscriber equipment receives from the configuration of common channel parameter of RNC transmission.

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