Summary of the invention
The embodiment of the present invention provides a kind of method, system and equipment of transfer of data, in order to solve the base station existing in prior art, configures identical CP type in all subframes, can cause the problem of the wasting of resources.
The method of a kind of transfer of data that the embodiment of the present invention provides, the method comprises:
Between base station and grand user terminal, pass through the first orthogonal frequency division multiplex OFDM symbol transmission data for direct projection link transmission; And
Between base station and relaying RN equipment, pass through the 2nd OFDM symbol transmission data of only transmitting for back haul link;
Wherein, the cyclic prefix CP type of a described OFDM symbol is that described base station configures according to the channel delay extend sizes of direct projection link, and the CP type of described the 2nd OFDM symbol is that described base station configures according to the channel delay extend sizes of back haul link.
The method of the another kind of transfer of data that the embodiment of the present invention provides, the method comprises:
Relaying RN equipment is determined the cyclic prefix CP type of the second orthogonal frequency division multiplex OFDM symbol only transmitting for back haul link according to the notice from base station, the CP type of wherein said the 2nd OFDM symbol is that described base station configures according to the channel delay extend sizes of back haul link;
Described RN equipment is according to definite CP type, by transmitting data between described the 2nd OFDM symbol and base station.
A kind of base station that the embodiment of the present invention provides, this base station comprises:
The first transport module, for and grand user terminal between by for the first orthogonal frequency division multiplex OFDM symbol transmission data of direct projection link transmission, and and relaying RN equipment between by only for the 2nd OFDM symbol transmission data of back haul link transmission;
Configuration module, for configuring the cyclic prefix CP type of a described OFDM symbol and the CP type that configures described the 2nd OFDM symbol according to the channel delay extend sizes of back haul link according to the channel delay extend sizes of direct projection link.
A kind of relaying RN equipment that the embodiment of the present invention provides, this RN equipment comprises:
Determination module, for determining that according to the notice from base station the cyclic prefix CP type of the second orthogonal frequency division multiplex OFDM symbol only transmitting for back haul link, the CP type of wherein said the 2nd OFDM symbol are that described base station configures according to the channel delay extend sizes of back haul link;
The second transport module, for according to definite CP type, by transmitting data between described the 2nd OFDM symbol and base station.
The system of a kind of transfer of data that the embodiment of the present invention provides, this system comprises:
Base station, for passing through the first orthogonal frequency division multiplex OFDM symbol transmission data for direct projection link transmission, and by the 2nd OFDM symbol transmission data of only transmitting for back haul link;
Grand user terminal, for passing through an OFDM symbol and the described base-station transmission data for direct projection link transmission;
RN equipment, for the 2nd OFDM symbol and the described base-station transmission data of passing through only to transmit for back haul link;
Wherein, the cyclic prefix CP type of a described OFDM symbol is that described base station configures according to the channel delay extend sizes of direct projection link, and the CP type of described the 2nd OFDM symbol is that described base station configures according to the channel delay extend sizes of back haul link.
Because the embodiment of the present invention is according to the channel delay spread scenarios of direct projection link and back haul link, be respectively direct projection link and back haul link configuration CP type, thereby can provide more resource for transmission, reduced resource overhead, improved resource utilization.
Embodiment
Between embodiment of the present invention base station and grand user terminal, pass through the OFDM symbol transmission data for direct projection link transmission, and and RN equipment between by only for the 2nd OFDM symbol transmission data of back haul link transmission, wherein the CP type of an OFDM symbol is that base station configures according to the channel delay extend sizes of direct projection link, and the CP type of the 2nd OFDM symbol is that base station is according to the channel delay extend sizes configuration of back haul link.Because the embodiment of the present invention is according to the channel delay spread scenarios of direct projection link and back haul link, be respectively direct projection link and back haul link configuration CP type, thereby can provide more resource for transmission, reduced resource overhead.
Wherein, the embodiment of the present invention can be applied in LTE-A system, also can be applied in other systems that contain RN equipment.
Below in conjunction with Figure of description, the embodiment of the present invention is described in further detail.
As shown in Figure 2, the system of embodiment of the present invention transfer of data comprises: base station 10, RN equipment 20 and grand user terminal 30.
Base station 10, for transmitting data between the OFDM symbol by for direct projection link transmission and grand user terminal 30, and by only for transmitting data between the 2nd OFDM symbol of back haul link transmission and RN equipment 20.
By the OFDM symbol transmission data for direct projection link transmission, comprise that base station 10 sends data and grand user terminal 30 to grand user terminal 30 and 10 sends data to base station;
By the 2nd OFDM symbol transmission data for direct projection link transmission, comprise that base station 10 sends data and RN equipment 20 to RN equipment 20 and 10 sends data to base station.
RN equipment 20, for the 2nd OFDM symbol by only transmitting for back haul link and base station 10 transmission data.
Grand user terminal 30, for the OFDM symbol by for direct projection link transmission and base station 10 transmission data.
Wherein, the CP type of an OFDM symbol is that base station 10 configures according to the channel delay extend sizes of direct projection link, and the CP type of the 2nd OFDM symbol is that base station 10 is according to the channel delay extend sizes configuration of back haul link.
Concrete, for direct projection link, base station 10 compares the channel delay extend sizes of direct projection link and conventional CP length, if the channel delay extend sizes of direct projection link is not more than conventional CP length, be that an OFDM symbol configures conventional CP, if the channel delay extend sizes of direct projection link is greater than conventional CP length, be an OFDM symbol configuration expansion CP;
For back haul link, base station 10 compares the channel delay extend sizes of back haul link and conventional CP length, if the channel delay extend sizes of back haul link is not more than conventional CP length, be that the 2nd OFDM symbol configures conventional CP, if the channel delay extend sizes of back haul link is greater than conventional CP length, be the 2nd OFDM symbol configuration expansion CP.
Determine need to the CP type for an OFDM symbol and the configuration of the 2nd OFDM symbol after, base station 10 also needs corresponding CP type to notify respectively to RN equipment 20 and grand user terminal 30.
For grand user terminal 30, a kind of implementation method is the correlation peak that grand user terminal 30 detects respectively auxiliary synchronous signals (SSS) and master sync signal (PSS), according to the distance between correlation peak, determines CP type;
For RN equipment 20, if RN equipment 20 also adopts above-mentioned detection method, the CP type detecting is the CP type of direct projection link, is not the CP type of back haul link, therefore need to adopt some signaling mechanisms to guarantee that RN equipment 20 obtains CP type.
Concrete, when RN equipment 20 is linked into network, the CP type of base station of RN equipment 20 the 2nd OFDM symbol is notified in base station 10 by high-level signaling, such as base station 10 is notified respectively each the RN equipment 20 to base station 10 management by RRC (Radio Resource Control, Radio Resource is controlled) signaling by the CP type of the 2nd OFDM symbol of configuration; Accordingly, RN equipment 20 obtains the CP type of the 2nd OFDM symbol in back haul link according to the high-level signaling receiving, and will be configured to corresponding CP for the 2nd OFDM symbol, for up transmission or the descending reception of back haul link.
As shown in Figure 3, the base station of the embodiment of the present invention comprises: the first transport module 100 and configuration module 110.
The first transport module 100, for and grand user terminal between by for OFDM symbol transmission data of direct projection link transmission, and and RN equipment between by only for the 2nd OFDM symbol transmission data of back haul link transmission.
Configuration module 110, for configure the CP type of an OFDM symbol according to the channel delay extend sizes of direct projection link, and according to the CP type of channel delay extend sizes configuration the 2nd OFDM symbol of back haul link.
For direct projection link, configuration module 110 compares the channel delay extend sizes of direct projection link and conventional CP length; If the channel delay extend sizes of direct projection link is not more than conventional CP length, be that an OFDM symbol configures conventional CP; If the channel delay extend sizes of direct projection link is greater than conventional CP length, be an OFDM symbol configuration expansion CP.
For back haul link, configuration module 110 compares the channel delay extend sizes of back haul link and conventional CP length; If the channel delay extend sizes of back haul link is not more than conventional CP length, be that the 2nd OFDM symbol configures conventional CP; If the channel delay extend sizes of back haul link is greater than conventional CP length, be the 2nd OFDM symbol configuration expansion CP.
Wherein, the embodiment of the present invention base station can further include: notification module 120.
Notification module 120, for notifying the CP type of RN equipment the 2nd OFDM symbol by high-level signaling.
As shown in Figure 4, the RN equipment of the embodiment of the present invention comprises: determination module 200 and the second transport module 210.
Determination module 200, for determine the CP type of the 2nd OFDM symbol only transmitting for back haul link according to the notice from base station, wherein the CP type of the 2nd OFDM symbol is that base station is according to the channel delay extend sizes configuration of back haul link;
The second transport module 210, for the CP type definite according to determination module 200, by transmitting data between the 2nd OFDM symbol and base station.
Wherein, determination module 200 can be according to determine the CP type of the 2nd OFDM symbol from base station high-level signaling.
As shown in Figure 5, the method for embodiment of the present invention the first transfer of data comprises the following steps:
Between step 501, base station and grand user terminal, by the first orthogonal frequency division multiplex OFDM symbol transmission data for direct projection link transmission, wherein the cyclic prefix CP type of an OFDM symbol is that base station is according to the channel delay extend sizes configuration of direct projection link.
Between step 502, base station and relaying RN equipment, by the 2nd OFDM symbol transmission data of only transmitting for back haul link, wherein the CP type of the 2nd OFDM symbol is that base station is according to the channel delay extend sizes configuration of back haul link.
Wherein, between step 501 and step 502, there is no inevitable sequential relationship, both can first perform step 501, then perform step 502; Also can first perform step 502, then perform step 501; Can also perform step 501 and step 502 simultaneously.
By the OFDM symbol transmission data for direct projection link transmission, comprise that base station sends data to grand user terminal to transmit data and grand user terminal to base station;
By the 2nd OFDM symbol transmission data for back haul link transmission, comprise that base station sends data to RN equipment sending data and RN equipment to base station.
Concrete, for direct projection link, base station compares the channel delay extend sizes of direct projection link and conventional CP length, if the channel delay extend sizes of direct projection link is not more than conventional CP length, be that an OFDM symbol configures conventional CP, if the channel delay extend sizes of direct projection link is greater than conventional CP length, be an OFDM symbol configuration expansion CP;
For back haul link, base station compares the channel delay extend sizes of back haul link and conventional CP length, if the channel delay extend sizes of back haul link is not more than conventional CP length, be that the 2nd OFDM symbol configures conventional CP, if the channel delay extend sizes of back haul link is greater than conventional CP length, be the 2nd OFDM symbol configuration expansion CP.
Determine need to the CP type for an OFDM symbol and the configuration of the 2nd OFDM symbol after, base station also needs corresponding CP type to notify respectively to RN equipment and grand user terminal.
For grand user terminal, a kind of implementation method is the correlation peak that grand user terminal detects respectively auxiliary synchronous signals SSS and master sync signal PSS, according to the distance between correlation peak, determines CP type;
For RN equipment, if RN equipment also adopts above-mentioned detection method, the CP type detecting is the CP type of direct projection link, is not the CP type of back haul link, therefore need to adopt some signaling mechanisms to guarantee that RN equipment obtains CP type.
Concrete, at RN equipment access during to network, the CP type of base station of RN equipment the 2nd OFDM symbol is notified in base station by high-level signaling, such as base station is notified respectively each the RN equipment to BTS management by RRC signaling by the CP type of the 2nd OFDM symbol of configuration, conventional CP and expansion CP can represent with different bit information (such as 0 or 1), base station will comprise bit information high-level signaling and notify the equipment to RN, RN equipment can be determined corresponding CP type according to the bit information in high-level signaling, wherein the correspondence of CP type and bit information can be passed through standard convention, can also be consulted to determine by base station and RN equipment, accordingly, RN equipment 20 obtains the CP type of the 2nd OFDM symbol in back haul link according to the high-level signaling receiving, will be configured to corresponding CP for the 2nd OFDM symbol, for up transmission or the descending reception of back haul link.
As shown in Figure 6, the method for embodiment of the present invention the second transfer of data comprises the following steps:
Step 601, RN equipment are determined the CP type of the 2nd OFDM symbol only transmitting for back haul link according to the notice from base station, wherein the CP type of the 2nd OFDM symbol is that base station is according to the channel delay extend sizes configuration of back haul link.
Step 602, RN equipment are according to definite CP type, by transmitting data between the 2nd OFDM symbol and base station.
In step 601, RN equipment is according to the CP type of determining the 2nd OFDM symbol from base station high-level signaling.
With two different application scenarioss, the solution of the present invention is described below.
Scene one, in macrocell, the channel delay of base station and grand user terminal communication link expansion is larger, needs configuration expansion CP can avoid intersymbol interference.But because the antenna of RN equipment is higher, and the communication link between base station is mainly direct projection footpath, the time delay expansion of channel is less, needs conventional CP can avoid intersymbol interference.
If according to the scheme of background technology, base station is according to maximum delay extend sizes configuration expansion CP, on the back haul link between base station and RN equipment, only the 2nd OFDM symbol quantity for back haul link transmission tails off relatively, and if RN equipment need to take an OFDM symbol switching time, it is large that the expense of switching time becomes.
If according to the solution of the present invention, base station is according to the channel delay extend sizes of direct projection link, and an OFDM symbol that is identified for direct projection link transmission all configures expansion CP, determines that the 2nd OFDM symbol only transmitting for back haul link all configures conventional CP.
In addition, in the subframe for back haul link, because grand user terminal need to utilize PDCCH (physical downlink control channel, Physical Downlink Control Channel) CRS (cell reference symbols) in carries out synchronously, so the OFDM symbol that the PDCCH of base station and grand user terminal takies is configured to expand CP.
In addition, at RN equipment side, PDCCH is for carrying the Downlink Control Information of RN community, and the channel delay expansion of the CP type YouRN community of the OFDM symbol that PDCCH takies determines.
Can be referring to Fig. 7 according to the subframe after the solution of the present invention configuration, because the 2nd OFDM symbol configures conventional CP, the scheme of comparing background technology has increased the quantity of the 2nd OFDM symbol, has reduced the expense of switching time.
For version 8 users, it thinks that the CP type in each subframe is expansion CP, and because the OFDM symbol for back haul link transmission is configured to conventional CP, grand user terminal data transmission is not dispatched in base station in back haul link subframe.
Scene two, in macrocell, the covering radius of base station is less, between base station and grand user terminal the channel delay of link expansion less, configure conventional CP and can avoid intersymbol interference.But RN equipment is outside cell coverage area, and for expanding covering, RN equipment still belongs to this base station.Link between base station and middle RN equipment is because propagation distance is larger, and channel delay expansion is also relatively large, need to expand CP and can avoid intersymbol interference.
If according to the scheme of background technology, base station is according to maximum delay extend sizes configuration expansion CP, on the back haul link between base station and grand user terminal, for an OFDM symbol quantity of direct projection link transmission, relatively tails off, and reduced cell throughout.
If according to the solution of the present invention, base station is according to the channel delay extend sizes of direct projection link, and an OFDM symbol that is identified for direct projection link transmission all configures conventional CP, determines that the 2nd OFDM symbol only transmitting for back haul link all configures expansion CP.
In addition, in the subframe for back haul link, because grand user terminal need to utilize the CRS in PDCCH, carry out synchronously, so the OFDM symbol that the PDCCH of base station and grand user terminal takies is configured to conventional CP.
In addition, at RN equipment side, PDCCH is for carrying the Downlink Control Information of RN community, and the channel delay expansion of the CP type YouRN community of the OFDM symbol that PDCCH takies determines.
Because an OFDM symbol configures conventional CP, the scheme of comparing background technology has increased the quantity of an OFDM symbol, has improved cell throughout.
The expense of scheme and the expense of background technology scheme for the embodiment of the present invention contrasts below, further illustrates the effect of the scheme of the embodiment of the present invention.
Suppose that OFDM symbol subcarrier spacing is Δ f=15kHz, expansion CP length is 512T
s, conventional CP is 160T
sor 144T
s, T wherein
s=1/ (15000 * 2048) s.
Take back haul link downlink transfer as example, and the channel delay expansion of supposing direct projection link need to be expanded CP and avoid intersymbol interference.
According to background technology, back haul link also needs to be configured to expand CP.At RN equipment side, in descending back haul link subframe, have 12 OFDM symbols, suppose that the first two OFDM symbol is for PDCCH, sending/receiving takies an OFDM symbol switching time, therefore the OFDM symbol receiving for downlink data is symbol 3-11, and totally 9 OFDM symbols, specifically referring to Fig. 8.
According to the scheme of the embodiment of the present invention, according to the channel delay extend sizes of back haul link, the OFDM symbol only transmitting for back haul link is configured to conventional CP.
Because conventional CP expands CP relatively, take less time-domain resource, change configuration and can save a part of time-domain resource, the time-domain resource of saving is:
(512T
s-160T
s) * 10=3520T
s≈ 115us or (512T
s-144T
s) * 10=3680T
s≈ 120us.
While adopting the OFDM symbol of conventional CP, length of field is 2208T
sor 2192T
s, the time-domain resource that therefore configures conventional CP saving can provide an extra OFDM symbol to receive for downlink data, and in addition remaining time-domain resource is 1312T
s≈ 43u
sor 1488T
s≈ 48us.
Be 17us-20us transmission/switching time of supposing RN equipment, and remaining time-domain resource still can provide time enough to switch for sending/receiving.As shown in Figure 9, comparing Fig. 8, is symbol 3-12 for the OFDM symbol of back haul link downlink transfer, totally 10 symbols, and resource utilization improves 11%.
Those skilled in the art should understand, embodiments of the invention can be provided as method, system or computer program.Therefore, the present invention can adopt complete hardware implementation example, implement software example or in conjunction with the form of the embodiment of software and hardware aspect completely.And the present invention can adopt the form that wherein includes the upper computer program of implementing of computer-usable storage medium (including but not limited to magnetic disc store, CD-ROM, optical memory etc.) of computer usable program code one or more.
The present invention is with reference to describing according to flow chart and/or the block diagram of the method for the embodiment of the present invention, equipment (system) and computer program.Should understand can be in computer program instructions realization flow figure and/or block diagram each flow process and/or the flow process in square frame and flow chart and/or block diagram and/or the combination of square frame.Can provide these computer program instructions to the processor of all-purpose computer, special-purpose computer, Embedded Processor or other programmable data processing device to produce a machine, the instruction of carrying out by the processor of computer or other programmable data processing device is produced for realizing the device in the function of flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame appointments.
These computer program instructions also can be stored in energy vectoring computer or the computer-readable memory of other programmable data processing device with ad hoc fashion work, the instruction that makes to be stored in this computer-readable memory produces the manufacture that comprises command device, and this command device is realized the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame.
These computer program instructions also can be loaded in computer or other programmable data processing device, make to carry out sequence of operations step to produce computer implemented processing on computer or other programmable devices, thereby the instruction of carrying out is provided for realizing the step of the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame on computer or other programmable devices.
Although described the preferred embodiments of the present invention, once those skilled in the art obtain the basic creative concept of cicada, can make other change and modification to these embodiment.So claims are intended to all changes and the modification that are interpreted as comprising preferred embodiment and fall into the scope of the invention.
From above-described embodiment, can find out: between embodiment of the present invention base station and grand user terminal, pass through the OFDM symbol transmission data for direct projection link transmission; And between base station and RN equipment by only for the 2nd OFDM symbol transmission data of back haul link transmission; Wherein the CP type of an OFDM symbol is that base station configures according to the channel delay extend sizes of direct projection link, and the CP type of the 2nd OFDM symbol is that base station is according to the channel delay extend sizes configuration of back haul link.
Because the embodiment of the present invention is according to the channel delay spread scenarios of direct projection link and back haul link, be respectively direct projection link and back haul link configuration CP type, thereby can provide more resource for transmission, reduced resource overhead, improved resource utilization.
Obviously, those skilled in the art can carry out various changes and modification and not depart from the spirit and scope of the present invention the present invention.Like this, if within of the present invention these are revised and modification belongs to the scope of the claims in the present invention and equivalent technologies thereof, the present invention is also intended to comprise these changes and modification interior.