A kind of system of selection of transformat combination of MAC layer and device thereofTechnical field
The present invention relates to the TD-SCDMA system, particularly relate to a kind of system of selection and device thereof of transformat combination of MAC layer.
Background technology
In the data link layer, MAC (Media Access Control, the medium access control) layer is RLC (Radio Link Control, Radio Link control) provide logic channel (Logical Channel, LC) be used to carry the data of RLC, and physical layer provides transmission channel (Transport Channel for the MAC layer, TrCH) be used to carry the data of MAC layer, every transmission channel TrCH can only be with some set form transmission data, these set forms are become TFS (Transport Format Set, TFS Transport Format Set), be multiplexed to a CCTrCH (Code Composite Transport Channel, the coded combination transmission channel) all transmission channel TrCH are configured a TFCS (Transport Format CombinationsSet, transport format combination set), an element among the TFCS is TFC (Transport FormatCombinations, transformat combination), it is at certain TTI (Transport Time Interval, Transmission Time Interval) combination of the TF (Transport Format, transformat) of each transmission channel TrCH constantly.Transformat TF can be divided into dynamic part and semi-static part, and dynamic part comprises TB (Transport Block, transmission block) size and transmission block number, and semi-static part comprises TTI, chnnel coding type, code rate, CRC size etc.Wherein, CRC (Cyclic Redundancy Check) is a cyclic redundancy check (CRC).
The transmission channel TrCH that MAC provides divide Common transport channel and dedicated transmission channel (DedicatedTransport Channel, DCH).Common transport channel and dedicated transmission channel can not be multiplexed on the CCTrCH, and their TFCS is disposed respectively.After having disposed the TFCS of the TFS of every transmission channel TrCH and CCTrCH, UE (User Equipment, subscriber equipment) the transformat communication that the MAC layer of equity just can be according to a preconcerted arrangement and between the UTRAN (UniversalTerrestrial Radio Access Network, Universal Terrestrial Radio Access Network).At each TTI.MAC is that every instantaneous source speed on the transmission channel TrCH is selected a TF in TFS, and the transformat combination of all transmission channel TrCH must be in TFCS.
When carrying out the design of mobile communcations system, guarantee that the MAC layer can select suitable TFC and can not select failure according to the data in the TTI, and will guarantee that the MAC layer can select TFC apace.
Summary of the invention
Technical problem to be solved by this invention is to provide system of selection and the device thereof of a kind of TFC of MAC layer, is used for selecting suitable TFC fast from the MAC layer of TD-SCDMA system.
To achieve these goals, the invention provides a kind of system of selection of transformat combination of MAC layer, be used for the TD-SCDMA system, it is characterized in that, this method comprises:
Step 1, MAC layer be according to attribute configuration one transport format combination set of transmission channel, and calculated the transformat indication of corresponding transmission channels by the transformat combination calculated value in the described transport format combination set;
Step 2, described MAC layer receive the Transmission Time Interval indication that physical layer sends, and obtain the logic channel that described transmission channel shone upon that needs to select transformat combination according to described Transmission Time Interval indication, and described logic channel is arranged; And
Step 3, described MAC layer selects to comprise the transformat combination of the described transformat indication that meets the demands of described logic channel according to putting in order from described transport format combination set of described logic channel, and sends data with this transformat combination;
In the described step 3, further comprise: described MAC layer is selected the transport format combination subset of described logic channel according to described logic channel institute data quantity transmitted, and selects to have the step of the transformat combination of lowest bit rate as described transformat combination in described transport format combination subset;
The step of the transport format combination subset of the described logic channel of described selection specifically comprises:
Described MAC layer is selected the transformat of described logic channel, and when described transformat data quantity transmitted takies more than or equal to buffer area, and described logic channel supports radio link control (RLC) size, and then described transformat is an optimal transmission formats; When described transformat data quantity transmitted takies less than buffer area, then the transformat of data quantity transmitted maximum is an optimal transmission formats, and indicates the set of the transformat that obtains described transmission channel correspondence according to the transformat of described optimal transmission formats correspondence.
The system of selection of the transformat combination of described MAC layer, wherein, in the described step 1, described attribute is the attribute that described MAC layer receives from radio resource control layer.
The system of selection of the transformat combination of described MAC layer, wherein, in the described step 1, described transport format combination set is represented by one group of transformat combination calculated value.
The system of selection of the transformat combination of described MAC layer wherein, in the described step 2, further comprises: described MAC layer according to described Transmission Time Interval indication judge to described transmission channel whether needs carry out the step of transport format combination selection.
The system of selection of the transformat combination of described MAC layer, wherein, in the described step 2, further comprise: described MAC layer is arranged described logic channel according to the priority of described logic channel, and the step of when priority is identical corresponding logic channel being arranged according to sequencing.
The system of selection of the transformat combination of described MAC layer, wherein, in the described step 3, further comprise: when the priority of described logic channel was limit priority, described MAC layer filtered the step of described transport format combination subset in the initial transport format combination set of radio resource control layer configuration.
To achieve these goals, the present invention also provides a kind of choice device of transformat combination of MAC layer, be used to comprise the TD-SCDMA system of MAC module, Radio Resource control module, it is characterized in that described choice device comprises MAC module and Radio Resource control module:
The MAC layer is according to attribute configuration one transport format combination set of transmission channel, by and calculate the transformat indication of corresponding transmission channels by the transformat combination calculated value in the described transport format combination set;
Described MAC module receives the Transmission Time Interval indication that physical layer sends, and obtains the logic channel that described transmission channel shone upon that needs to select transformat combination according to described Transmission Time Interval indication, and described logic channel is arranged;
Described MAC module selects to comprise the transformat combination of the described transformat indication that meets the demands of described logic channel according to putting in order of described logic channel from described transport format combination set, and sends data with this transformat combination;
Described MAC module is selected the transport format combination subset of described logic channel according to described logic channel institute data quantity transmitted, and selects to have the transformat combination of lowest bit rate as described transformat combination in described transport format combination subset;
Particularly, described MAC module is selected the transformat of described logic channel, and when described transformat data quantity transmitted takies more than or equal to buffer area, and described logic channel supports the RLC size, and then described transformat is an optimal transmission formats; When described transformat data quantity transmitted takies less than buffer area, then the transformat of data quantity transmitted maximum is an optimal transmission formats, and indicates the set of the transformat that obtains described transmission channel correspondence according to the transformat of described optimal transmission formats correspondence.
The choice device of the transformat combination of described MAC layer, wherein, described attribute is the attribute that described MAC module receives from described Radio Resource control module.
With respect to the system of selection of existing TFC, the present invention has following characteristics and advantage:
1) taken into full account the situation of actual realization, increased (Calculated Transport Format Combination from CTFC, the transformat combination calculated value) obtains the algorithm of TFI (Transport FormatIndicator, transformat indication) fast;
2) not that every logic channel all needs query caching to take, increased and judged transmission channel according to TTI indication whether needs carry out the step that TFC selects, reduced the logic channel number of participating in the TFC selection, improved processing speed;
3) in strict accordance with the principle of agreement, comparatively speaking, the algorithm that is adopted has taken into full account total data to be transferred amount on the transmission channel and has selected.
Describe the present invention below in conjunction with the drawings and specific embodiments, but not as a limitation of the invention.
Description of drawings
Fig. 1 is the system of selection flow chart of the TFC of MAC layer of the present invention;
Fig. 2 is the choice device structure chart of the TFC of MAC layer of the present invention.
Embodiment
Below in conjunction with the drawings and specific embodiments technical scheme of the present invention is made further more detailed description.
As shown in Figure 1, be the system of selection flow chart of the TFC of MAC layer of the present invention.This flow process is described a kind of TFC system of selection of optimization, improves the speed that TFC selects.Before describing realization flow, the basic demand of in the agreement TFC being selected is described.
By giving priority of logical channels of each logic channel LC assignment, RRC (Radio ResourceControl, Radio Resource control) scheduling of uplink data can be controlled in the sublayer, and the TFC in the user equipment (UE) selects to carry out according to the priority of logical channels of RRC sublayer institute assignment.Because logic channel LC has absolute priority, so user equipment (UE) should as far as possible at first send the data with limit priority.
When carrying out the TFC selection, which TFC user equipment (UE) will assess can be supported.Before selecting a suitable TFC, the set that at first needs to set up an effective TFC.The selection of TFC should effectively carried out in the TFC set, and satisfies following condition successively:
A1) there are not other TFC can send the data of higher priority than selected TFC;
A2) there are not other TFC than sending more data on the inferior high priority logic channel; Reuse this rule for other remaining priority;
A3) there are not other TFC to have lower bit rate than this TFC.
After the basic demand that TFC selects is narrated, further describe the realization flow of selection of the TFC of MAC layer below, this flow process specifically comprises:
Step 100, beginning;
Step 101, initialization operation refers to that mainly the MAC layer receives the relevant configuration of TFCS from rrc layer, and TFCS represents with one group of CTFC that generally CTFC is the efficient signaling instrument that is used for TFC, and CTFC is calculated by following formula:
If I is the number of contained transmission channel among the TFC.Each transmission channel TrCHi, i=1,2 ..., I has LiIndividual transformat indication.Be TFIiDesirable LiIndividual value, TFIi∈ 0,1,2 ..., Li-1}.TFI is (TransportFormat Indicator, transformat indication).
Definitionwhere?i=1,2,…,I,and?L0=1。
If TFC (TFI1, TFI2 ..., TFII) be transformat combination, wherein TrCH1 has transformat indication TFI1, and TrCH2 has transformat indication TFI2, or the like.Correspondingly, CTFC (TFI1, TFI2 ..., TFII) calculate with following formula:
For each combination of TFI, all there is a unique CTFC corresponding with it.
Step 102, physical layer sends the TTI indication to the MAC layer, and MAC receives after the TTI indication, indication judges whether TTI meets the TTI of each transmission channel according to TTI, and the buffer area that inquiry afterwards meets the logic channel that is shone upon on the transmission channel of TTI takies (BO); If do not meet, change step 106 over to and carry out.
Step 103 begins to select TFC from the logic channel with limit priority, and concrete steps are:
B1) logic channel that needs is carried out shine upon on the transmission channel that TFC selects is arranged according to priority of logical channels, to identical the arranging according to sequencing of priority, obtains list of logical channels;
Logic channel is arranged according to priority of logical channels, be meant logic channel is arranged according to the order from the high priority to the low priority;
From TFCS, select the transformat TF of each transmission channel according to the order of logic channel from the high priority to the low priority, thereby select a TFC according to transformat TF.
B2) at above-mentioned list of logical channels, in the transport format combination subset of last time selecting, select effective TFCS successively, be in the initial pool universal class of RRC sublayer configuration, to select at the combination selection of the logic channel of limit priority.
Select the process of transport format combination subset as follows at a logic channel:
Logic channel is selected its best transformat, the standard of selection be can data quantity transmitted more than or equal to BO, and RLCSize is supported by this logic channel; If all TF can data quantity transmitted all less than this BO, the TFI of TF correspondence that then can the transmitted data amount maximum is a selection result.The TF that selects should derive from the pairing TFS of the transmission channel that is mapped among the TFCS, promptly calculates TFI on the corresponding transmission channel by CTFC.Concrete algorithm following (c language):
M=CTFC;
I=I;
While(I>0){
TFII=floor(m/Pi);
M=M%Pi;
I=I-1;
}
Step 104, after each logic channel has been selected, all obtain a transport format combination subset, owing to have of the mapping of a plurality of logic channels in the actual selection process to transmission channel, the selection of above-mentioned transport format combination set makes that efficient set is more and more littler, finally can determine the set of a TFC or TFC,, then in this set, select the set that can send the data that will send and have minimum filling hash if final result is the set of a TFC; Selection has the TFC of lowest bit rate;
Step 105 sends data according to selected TFC;
Step 106 finishes.
As shown in Figure 2, be the choice device structure chart of the TFC of MAC layer of the present invention.Thisdevice 200 comprises: mediumaccess control module 21, RadioResource control module 22,physical layer 23, logiclink control module 24.
Wherein, mediumaccess control module 21 is MAC modules, and RadioResource control module 22 is RRC modules, and logiclink control module 24 is RLC modules.
MAC module 21 is by providing logic channel toRLC module 24, with the data of carrying rlc layer;Physical layer 23 provides transmission channel toMAC module 21, with the data of carrying MAC layer.
MAC module 21 is used for attribute (or claiming attribute information) the configuration TFCS according to transmission channel TrCH, and is calculated the TFI of corresponding transmission channels by the CTFC among the TFCS; The TTI indication that reception sends fromphysical layer 23, the logic channel that transmission channel shone upon that needs to select transformat combination is obtained in indication according to TTI, and logic channel is arranged;
MAC module 21 selects to comprise the transformat combination of the TFI that meets the demands of logic channel according to putting in order of logic channel from transport format combination set, and sends data with this transformat combination.
Whether theMAC module 21 selected transformat combination TFI that depends on transformat combination that whether meets the demands meets the demands, and when TFI met the demands, then transformat combination also met the demands.
Wherein,MAC module 21 is further indicated the Transmission Time Interval TTI that judges whether to meet each transmission channel TrCH according to TTI when each TTI indication arrives; And query mappings meets the BO of logic channel of transmission channel TrCH of the TTI of transmission channel TrCH at these;
Wherein,MAC module 21 is selected TFC at each Transmission Time Interval TTI according to data volume waiting for transmission, and sends data according to selected TFC, particularly: logic channel is arranged according to MLP; From TFCS, select the TF of each transmission channel according to the order of logic channel from the high priority to the low priority, thereby select a TFC; Send data according to the TFC that selects.
RRC module 22 is used for sending described attribute toMAC module 21.
Adopt the inventive method to guarantee that the MAC layer of TD-SCDMA system can select suitable TFC according to the data in the TTI apace, thereby improved the speed that TFC selects greatly.
Certainly; the present invention also can have other various embodiments; under the situation that does not deviate from spirit of the present invention and essence thereof; those of ordinary skill in the art work as can make various corresponding changes and distortion according to the present invention, but these corresponding changes and distortion all should belong to the protection range of the appended claim of the present invention.