CN104812089B - The communication means and UE of D2D - Google Patents

Abstract

The present invention provides the communication means of D2D a kind of and UE, this method includes that the D2D UE in first community determines the reception to the D2D discovery signal of second community periodically, and the corresponding resource allocation information of D2D discovery signal is obtained, D2D is then received according to reception timing and resource allocation information and finds signal.Through the invention, it solves the problems, such as that D2D has found that the user equipment of medium and small interval is difficult to realize Timing Synchronization in the related technology, and then has achieved the effect that the user equipment Timing Synchronization of D2D discovery medium and small interval.

Description

The communication means and UE of D2D

Technical field

The present invention relates to the communications fields, in particular to a kind of equipment to equipment (Device to Device, abbreviation D2D communication means and user equipment (User Equipment, referred to as UE)).

Background technique

In a cellular communication system, when having business transmission between two user equipmenies, for example, user equipment 1(UE1) it arrives User equipment 2(UE2) business datum, first by air interface transmission to cell where UE1 base station (Base Station, or Person is known as Node B or evolution (evolved) Node B), the base station is by core net by the user data transmission to where UE2 Above-mentioned business datum is passed through air interface transmission to UE2 again by the base station of cell, the base station of cell where UE2.Fig. 1 is according to related skill The cellular communication schematic diagram of the UE positioned at same base station cell of art, as shown in Figure 1, when to be located at the same honeycomb small by UE1 and UE2 Area, although two UE are still needed when data are transmitted through core net transfer by the MPS process of the same base station, and primary Data transmission still can consume two parts of radio spectrum resources.

It can be seen that if UE1 and UE2 is located at same cell and at a distance of relatively close, above-mentioned cellular communication method It is apparently not optimal.And in fact, with mobile communication business diversification, for example, social networks, e-payment etc. apply In a wireless communication system universal, so that the business transmission demand between short distance user is growing.Therefore, D2D's is logical Letter mode is increasingly subject to extensive concern.Fig. 1 a is to be communicated to illustrate according to the D2D of the UE positioned at same base station cell of the relevant technologies Figure, D2D refer to that business datum without the forwarding of base station and core net, directly passes through air interface transmission to target by source user equipment User equipment, also referred to as adjacent service (Proximity Service, abbreviation ProSe).As shown in Figure 1a, two UE it Between business datum without base station and core net, but directly transmitted between two UE.For the user of short-range communication For, D2D not only saves radio spectrum resources, and reduces the data transmission pressure of core net.

In cellular communications, it is the Timing Synchronization both realized in time that base station and UE, which carry out the premise of data communication, UE realizes the downlink Timing Synchronization with base station by the downlink synchronous signal that detection base station is sent, by compensating timing advance (Timing Advance, referred to as TA) realizes the uplink Timing Synchronization with base station, wherein synchronization signal includes main synchronous letter Number (Primary Synchronous Signal, referred to as PSS) and secondary synchronization signal (Secondary Synchronous Signal, referred to as SSS).

Equally, in D2D communication system, D2D discovery signal sends UE and receives and is also required to realize Timing Synchronization between UE, It is possible to be correctly received and demodulate D2D discovery signal.For the signal communication of the D2D UE in the same cell, very certainly So, according to the downlink synchronous signal that the corresponding base station in affiliated subdistrict is sent or TA value can be combined to carry out relevant compensation, come Timing Synchronization is obtained, to realize the Timing Synchronization sent between D2D UE and reception D2D UE.And for the D2D UE of minizone Signal communication, it is necessary to divide situation and different.For synchronous on-premise network, the timing reference of different base station is stringent synchronization, D2D UE between neighboring community can also obtain Timing Synchronization according to the identical method of D2D UE in cell, complete neighboring community it Between communicate between difference D2D UE.But for the network of asynchronous deployment, the timing reference of different base station is not stringent right Together, at this point, being subordinate to the D2D UE of neighboring community under different base station, the downlink synchronous signal or TA issued according to respective own base station Value can not achieve Timing Synchronization.

Aiming at the problem that user equipment of the discovery medium and small interval of D2D in the related technology is difficult to realize Timing Synchronization, at present still It does not put forward effective solutions.

Summary of the invention

The present invention provides the communication means of D2D a kind of and UE, find medium and small interval at least to solve D2D in the related technology User equipment is difficult to realize the problem of Timing Synchronization.

According to an aspect of the invention, there is provided a kind of D2D communication means, comprising: the D2D user in first community sets Standby UE determines the reception timing to the D2D discovery signal of second community, and obtains the corresponding resource allocation of the D2D discovery signal Information；The D2D UE receives the D2D according to the reception timing and the resource allocation information and finds signal.

Preferably, the D2D UE determines that the reception timing to the D2D discovery signal of the second community includes: institute State the downlink synchronous signal that D2D UE detects the second community；The D2D UE believes according to the detected down-going synchronous It number determines the transmission timing of D2D discovery signal, and the transmission timing is determined as receptions periodically.

Preferably, the D2D UE determines that the reception timing to the D2D discovery signal of the second community includes: institute State the downlink synchronous signal that D2D UE detects the second community that at least one UE in the second community is forwarded, wherein At least one described UE is determined according to the Reference Signal Received Power RSRP or timing advance TA of the UE in the second community 's；The D2D UE determines the transmission timing of the D2D discovery signal according to the detected downlink synchronous signal, and will The transmission timing is determined as the reception timing.

Preferably, at least one described UE be according to the RSRP or TA of the UE in the second community determine include: institute Stating at least one UE is that the second community own base station determines the corresponding first community of UE in the second community After difference between RSRP and the second community RSRP, the maximum M UE of the difference is selected to obtain, wherein the M is Positive integer；Or at least one described UE is that the second community own base station obtains the respective TA value of UE in the second community Afterwards, the maximum N number of UE of the TA value is selected to obtain, wherein the N is positive integer.

Preferably, the D2D UE determines that the reception timing to the D2D discovery signal of the second community includes: institute State the downlink synchronous signal that D2D UE detects the second community of other UE forwarding in the first community, wherein it is described its His UE is the UE that the downlink synchronous signal of the second community is able to detect that in the first community；The D2D UE is according to institute The downlink synchronous signal detected determines the transmission timing of the D2D discovery signal, and the transmission timing is determined as The reception timing.

Preferably, the D2D UE determines that it includes: described for receiving timing to the D2D discovery signal of the second community D2D UE receives the instruction message of the D2D UE own base station, wherein the instruction message carries the second community Timing information；The D2D UE determines the reception timing according to the timing information.

Preferably, the timing information is obtained by way of at least one of: passing through the affiliated base of the first community The X2 interface interaction stood between the second community own base station is obtained from the second community own base station；Pass through described Radio open or non-standard interface between one cell own base station and the second community own base station are from the second community Own base station obtains；By being able to detect that the UE of the downlink synchronous signal of the second community is reported in the first community It is obtained in information.

Preferably, the timing information of the second community includes: to be reported according at least one UE in the first community The first community timing offset determine the second community standard deviation amount, wherein the timing offset It is to be obtained according to the downlink synchronous signal of the first community and the downlink synchronous signal of the second community.

Preferably, obtaining the corresponding resource allocation information of the D2D discovery signal includes: D2D UE detection institute State the broadcast message of second community；The D2D UE obtains the resource allocation information from the broadcast message.

Preferably, obtaining the corresponding resource allocation information of the D2D discovery signal includes: D2D UE detection institute State the downlink synchronous signal of the second community of at least one UE forwarding in second community, wherein at least one described UE It is to be determined according to the RSRP or TA of the UE in the second community；The D2D UE is according to the detected down-going synchronous The different location that the primary synchronization signal PSS and secondary synchronization signal SSS of signal map respectively in forwarding subframe, obtains the resource Distribute information.

Preferably, obtaining the corresponding resource allocation information of the D2D discovery signal includes: D2D UE detection institute State the downlink synchronous signal of the second community of other UE forwarding in first community, wherein other described UE are described first The UE of the downlink synchronous signal of the second community is able to detect that in cell；The D2D UE is according to detected institute The different location that the primary synchronization signal PSS and secondary synchronization signal SSS of downlink synchronous signal map respectively in forwarding subframe is stated, is obtained Take the resource allocation information.

Preferably, obtaining the corresponding resource allocation information of the D2D discovery signal includes: that the D2D UE receives institute State the instruction message of D2D UE own base station, wherein the instruction message carries the resource allocation information；The D2D UE The resource allocation information is obtained from the instruction message.

Preferably, the resource allocation information carried in the instruction message is obtained by way of at least one of It gets: by the interaction of X2 interface between the first community own base station and the second community own base station from described the Two cell own base stations obtain；Pass through the wireless sky between the first community own base station and the second community own base station Mouth or non-standard interface interaction are obtained from the second community own base station；It is described by being able to detect that in the first community The reporting in information for UE of the resource allocation information of second community obtains;It is interactive from the second community by upper layer network Own base station obtains, wherein the upper layer network is above the Web communication layer of the base station layer.

Preferably, obtaining the corresponding resource allocation information of the D2D discovery signal includes: to receive the second community The resource allocation information that directly forwards of UE.

According to another aspect of the present invention, a kind of UE is provided, comprising: determining module, for determining to second community D2D has found the reception timing of signal；Module is obtained, for obtaining the corresponding resource allocation information of the D2D discovery signal；It receives Module finds signal for receiving the D2D according to the reception timing and the resource allocation information.

Preferably, the determining module includes: detection unit, for detecting the downlink synchronous signal of the second community； Determination unit, for determining the transmission timing of the D2D discovery signal according to the detected downlink synchronous signal, and will The transmission timing is determined as the reception timing.

Preferably, the determining module includes: detection unit, is turned for detecting at least one UE in the second community The downlink synchronous signal of the second community of hair, wherein at least one described UE is according to the UE in the second community What Reference Signal Received Power RSRP or timing advance TA was determined；Determination unit, for same according to the detected downlink Step signal determines the transmission timing of the D2D discovery signal, and the transmission timing is determined as the reception timing.

Preferably, the determining module includes: detection unit, for detecting the institute that other UE are forwarded in the first community State the downlink synchronous signal of second community, wherein other described UE are to be able to detect that described second is small in the first community The UE of the downlink synchronous signal in area；Determination unit, for determining that the D2D is sent out according to the detected downlink synchronous signal The transmission timing of existing signal, and the transmission timing is determined as the reception timing.

Preferably, the determining module includes: detection unit, and the instruction for receiving the D2D UE own base station disappears Breath, wherein the instruction message carries the timing information of the second community；Determination unit, for being believed according to the timing Breath determines the reception timing.

Preferably, the acquisition module includes: resources measurement unit, for detecting the broadcast message of the second community； Acquiring unit, for obtaining the resource allocation information from the broadcast message.

Preferably, the acquisition module includes: resources measurement unit, for detecting at least one of described second community The downlink synchronous signal of the second community of UE forwarding, wherein at least one described UE is according in the second community What the RSRP or TA of UE was determined；Acquiring unit, for according to the primary synchronization signal PSS of the detected downlink synchronous signal and The different location that secondary synchronization signal SSS maps respectively in forwarding subframe, obtains the resource allocation information.

Preferably, the acquisition module includes: resources measurement unit, is forwarded for detecting other UE in the first community The second community downlink synchronous signal, wherein other described UE are that described is able to detect that in the first community The UE of the downlink synchronous signal of two cells；Acquiring unit, for the master according to the detected downlink synchronous signal The different location that synchronization signal PSS and secondary synchronization signal SSS maps respectively in forwarding subframe obtains the resource allocation letter Breath.

Preferably, the acquisition module includes: resources measurement unit, for receiving the instruction of the D2D UE own base station Message, wherein the instruction message carries the resource allocation information；Acquiring unit, for being obtained from the instruction message Take the resource allocation information.

Preferably, the acquisition module includes: acquiring unit, the institute that the UE for receiving the second community is directly forwarded State resource allocation information.

Through the invention, it is fixed to the reception of the D2D discovery signal of second community to be determined using the D2D UE in first community When, and the corresponding resource allocation information of D2D discovery signal is obtained, D2D is then received according to reception timing and resource allocation information It was found that signal, solves the problems, such as that D2D has found that the user equipment of medium and small interval is difficult to Timing Synchronization in the related technology, and then realize The user equipment Timing Synchronization of D2D discovery medium and small interval.

Detailed description of the invention

The drawings described herein are used to provide a further understanding of the present invention, constitutes part of this application, this hair Bright illustrative embodiments and their description are used to explain the present invention, and are not constituted improper limitations of the present invention.In the accompanying drawings:

Fig. 1 is the cellular communication schematic diagram according to the UE positioned at same base station cell of the relevant technologies；

Fig. 1 a is the D2D communication scheme according to the UE positioned at same base station cell of the relevant technologies；

Fig. 2 is the flow chart of D2D communication means according to an embodiment of the present invention;

Fig. 3 is the structural block diagram of UE according to an embodiment of the present invention；

Fig. 3 a is another structural block diagram of UE according to an embodiment of the present invention；

Fig. 3 b is another structural block diagram of UE according to an embodiment of the present invention；

Fig. 4 is the schematic diagram according to the radio resource structure of the relevant technologies；

Fig. 4 a is to dispose schematic diagram according to the network of the cellular radio Communication system of the relevant technologies；

Fig. 5 is the schematic diagram of the first realization principle of D2D discovery signal communication according to the preferred embodiment of the invention；

Fig. 6 is the schematic diagram of second of realization principle of D2D discovery signal communication according to the preferred embodiment of the invention；

Fig. 7 is the forwarding resource location exemplary diagram of pass-through mode one according to an embodiment of the present invention；

Fig. 8 is the Mapping Examples of the UE forwarding synchronization signal of corresponding pass-through mode one according to an embodiment of the present invention；

Fig. 9 is that one of the resource location of the forwarding synchronization signal of corresponding pass-through mode two according to an embodiment of the present invention shows Example；

Figure 10 is the Mapping Examples of the UE forwarding synchronization signal of corresponded manner two according to an embodiment of the present invention；

Figure 11 is the schematic diagram of the third realization principle of D2D discovery signal communication according to the preferred embodiment of the invention；

Figure 12 is the schematic diagram of the 4th kind of realization principle of D2D discovery signal communication according to the preferred embodiment of the invention； And

Figure 13 is D2D signal communication structural schematic diagram according to an embodiment of the present invention.

Specific embodiment

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings and in combination with Examples.It should be noted that not conflicting In the case of, the features in the embodiments and the embodiments of the present application can be combined with each other.

A kind of D2D communication means is provided in the present embodiment, and Fig. 2 is D2D communication means according to an embodiment of the present invention Flow chart, as shown in Fig. 2, the process includes the following steps:

Step S202, the D2D UE in first community determine the reception timing to the D2D discovery signal of second community, and obtain Take the corresponding resource allocation information of D2D discovery signal；

Step S204, D2D UE receives D2D discovery signal according to timing and resource allocation information is received.

Through the above steps, it solves the user equipment that D2D communicates medium and small interval in the related technology and is difficult to realize timing together The problem of step, and then achieved the effect that the user equipment Timing Synchronization of D2D communication medium and small interval.

There are many kinds of the methods for determining reception timing, it is preferable that can be realized by following methods:

The downlink synchronous signal of mode one, D2D UE detection second community, and according to detected downlink synchronous signal It determines the transmission timing of D2D discovery signal, and transmission timing is determined as to receive timing.

The downlink synchronous signal for the second community that at least one UE in mode two, D2D UE detection second community is forwarded, Wherein, at least one UE is determined according to the RSRP or TA of the UE in second community；D2D UE is according to detected downlink Synchronization signal determines the transmission timing of D2D discovery signal, and the transmission timing is determined as to receive timing.

Preferably, determine that the mode of at least one UE can have following two: second community own base station determines that second is small After the difference between UE corresponding adjacent area RSRP and serving cell RSRP in area, the maximum M UE of the difference is selected As at least one UE, wherein M is positive integer；Alternatively, second community own base station obtains the respective TA of UE in second community After value, select the maximum N number of UE of TA value as at least one UE, wherein N is positive integer.

Certainly, in other examples, at least one UE: the base station of second community can also be determined as follows A threshold value is safeguarded according to the UE serving cell reported and the RSRP of adjacent area, and this threshold value is indicated to second by signaling All UE in cell, all UE in second community are adjudicated according to the difference D of the serving cell measured and adjacent cell RSRP, When D value is less than above-mentioned thresholding, UE just determines itself for a member at least one UE, further to forward under second community Line synchronising signal.

The downlink synchronous signal of the second community of other UE forwarding in mode three, D2D UE detection first community, wherein its His UE is the UE that the downlink synchronous signal of second community is able to detect that in first community；D2D UE is according to detected downlink Synchronization signal determines the transmission timing of D2D discovery signal, and transmission timing is determined as to receive timing.

Mode four, D2D UE receive the instruction message of D2D UE own base station, wherein it is small that the instruction message carries second The timing information in area；D2D UE is determined according to timing information receives timing.Preferably, timing information can by it is following at least it One mode obtains: interactive from second community by the X2 interface between first community own base station and second community own base station Own base station obtains；Pass through the radio open or non-standard interface between first community own base station and second community own base station It is obtained from second community own base station；By be able to detect that in first community the downlink synchronous signal of second community UE it is upper It notifies and obtains in breath.Wherein, the timing information of second community can be reported according at least one UE in first community The standard deviation amount for the second community that the timing offset of one cell determines, which is the downlink according to first community What the downlink synchronous signal of synchronization signal and the second community obtained.

By above-mentioned several ways, the reception timing of second community can be quickly determined, to further realize D2D hair The Timing Synchronization of existing medium and small interval user equipment.

Obtain resource allocation information method also there are many kinds of, it is preferable that can be realized by following methods:

The broadcast message of mode one, D2D UE detection second community, and resource allocation information is obtained from broadcast message.

The downlink synchronous signal for the second community that at least one UE in mode two, D2D UE detection second community is forwarded, Wherein, at least one UE is determined according to the RSRP or TA of the UE in second community；D2D UE is according to detected downlink The different location that the PSS and SSS of synchronization signal map respectively in forwarding subframe, obtains resource allocation information.

The downlink synchronous signal of the second community of other UE forwarding in mode three, D2D UE detection first community, wherein its His UE is the UE that the downlink synchronous signal of second community is able to detect that in first community；D2D UE is according to detected downlink The different location that the PSS and SSS of synchronization signal map respectively in forwarding subframe, obtains resource allocation information.

Mode four, D2D UE receive the instruction message of D2D UE own base station, wherein instruction message carries resource allocation Information；D2D UE obtains resource allocation information from instruction message.Preferably, the resource allocation information carried in instruction message can It is got in a manner of through at least one of: by between first community own base station and second community own base station X2 interface interaction is obtained from two cell own base stations of institute；By between first community own base station and second community own base station Radio open or non-standard interface interaction are obtained from second community own base station；By being able to detect that second is small in first community Reporting in information for the UE of the resource allocation information in area obtains;It is obtained by upper layer network interaction from second community own base station, Wherein, upper layer network is above the Web communication layer of base station layer.

The resource allocation information that mode five, the UE for receiving second community are directly forwarded.

By above-mentioned several ways, the corresponding resource allocation information of D2D discovery signal can be rapidly obtained, to realize The Timing Synchronization of user equipment in D2D discovery.

A kind of UE is additionally provided in the present embodiment, and the UE is for realizing above-described embodiment and preferred embodiment, Carried out repeating no more for explanation.As used below, the software and/or hardware of predetermined function may be implemented in term " module " Combination.Although device described in following embodiment is preferably realized with software, hardware or software and hardware The realization of combination is also that may and be contemplated.

Fig. 3 is the structural block diagram of UE according to an embodiment of the present invention, as shown in figure 3, the UE comprises determining that module 32, is used In the reception timing for determining that the D2D to second community has found signal；Module 34 is obtained, it is corresponding for obtaining D2D discovery signal Resource allocation information；Receiving module 36 finds signal for receiving D2D according to reception timing and resource allocation information.

Fig. 3 a is another structural block diagram of UE according to an embodiment of the present invention, and as shown in Figure 3a, it includes Fig. 3 which, which removes, Shown in all modules, wherein determining module 32 include detection unit 322 and determination unit 324.

Preferably, detection unit 322, for detecting the downlink synchronous signal of second community；Determination unit 324 is used for root The transmission timing of D2D discovery signal is determined according to detected downlink synchronous signal, and transmission timing is determined as to receive timing.

Preferably, detection unit 322, the downlink of the second community for detecting the forwarding of at least one UE in second community Synchronization signal, wherein at least one UE is determined according to the RSRP or TA of the UE in second community；Determination unit 324, is used for The transmission timing of D2D discovery signal is determined according to detected downlink synchronous signal, and transmission timing is determined as receiving and is determined When.

Preferably, detection unit 322, for detecting the down-going synchronous letter for the second community that other UE are forwarded in first community Number, wherein other UE are the UE that the downlink synchronous signal of second community is able to detect that in first community；Determination unit 324 is used In the transmission timing for determining D2D discovery signal according to detected downlink synchronous signal, and transmission timing is determined as receiving Periodically.

Preferably, detection unit 322, for receiving the instruction message of D2D UE own base station, wherein instruction message carries There is the timing information of second community；Determination unit 324 receives timing for determining according to timing information.

Fig. 3 b is another structural block diagram of UE according to an embodiment of the present invention, and as shown in Figure 3b, it includes Fig. 3 which, which removes, Shown in all modules, wherein obtain module 34 include resources measurement unit 342 and acquiring unit 344.

Preferably, resources measurement unit 342, for detecting the broadcast message of second community；Acquiring unit 344, for from Resource allocation information is obtained in broadcast message.

Preferably, resources measurement unit 342, for detecting the second community of at least one UE in second community forwarding Downlink synchronous signal, wherein at least one UE is determined according to the RSRP or TA of the UE in second community；Acquiring unit 344, For the different location that the PSS and SSS according to detected downlink synchronous signal map respectively in forwarding subframe, resource is obtained Distribute information.

Preferably, resources measurement unit 342, the downlink for detecting the second community that other UE are forwarded in first community are same Walk signal, wherein other described UE are the UE that the downlink synchronous signal of second community is able to detect that in first community；It obtains single Member 344, the different location for being mapped respectively in forwarding subframe according to the PSS and SSS of detected downlink synchronous signal, Obtain resource allocation information.

Preferably, resources measurement unit 342, for receiving the instruction message of D2D UE own base station, wherein instruction message Carry resource allocation information；Acquiring unit 344, for obtaining resource allocation information from instruction message.

Preferably, obtaining module 34 can also only include: acquiring unit 344, and the UE for receiving second community directly turns The resource allocation information of hair.

It is illustrated below in conjunction with preferred embodiment, preferred embodiment below combines above-described embodiment and its preferred implementation Mode.

The embodiment of the present invention is suitable for cellular radio Communication system or network.Common cellular radio Communication system can be with base In CDMA (Code Division Multiplexing Access, referred to as CDMA) technology, frequency division multiple access (Frequency Division Multiplexing Access, referred to as FDMA) technology, orthogonal frequency division multiple access (Orthogonal-FDMA, referred to as OFDMA) technology, single-carrier frequency division multiple access (Single Carrier-FDMA, referred to as SC-FDMA) technology etc..For example, third generation cooperative partner program (3rd Generation Partnership Project, letter Referred to as 3GPP) long term evolution (Long Term Evolution, referred to as LTE)/senior long term evolution (LTE-Advanced, letter Referred to as LTE-A) cellular communication system downlink (or be forward link) is based on OFDMA technology, uplink (or be anti- To link) it is based on SC-FDMA multiple access technology.It is following then be possible to support mixed multiple access technology on a road Ge Lian.

In OFDMA/SC-FDMA system, when the radio resource (Radio Resource) for communication is-frequency bidimensional Form.For example, the communication resource of uplink and downlink link is all with nothing in the direction of time for LTE/LTE-A system Line frame (radio frame) is unit division, and each wireless frame length is 10ms, the subframe (sub- for being 1ms comprising 10 length Frame), each subframe includes two time slots (slot) that length is 0.5ms, as shown in Figure 4.And according to cyclic prefix The configuration of (Cyclic Prefix, CP) is different, and each time slot may include 6 or 7 OFDM or SC-FDM symbols.

In frequency direction, resource is unit division, specifically in the communications, frequency domain resource point with subcarrier (subcarrier) The minimum unit matched is resource block (Resource Block, referred to as RB), a PRB(Physical of corresponding physical resource RB, Physical Resource Block).One PRB includes 12 subcarriers in frequency domain, a time slot corresponding to time domain.Each OFDM/SC- The resource of a corresponding subcarrier is known as resource unit (Resource Element, abbreviation RE) on FDM symbol, as shown in Figure 4.

In LTE/LTE-A cellular communication, user equipment (UE) passes through detection synchronization signal (Synchronization Signal, referred to as SS) discovery LTE network.Synchronization signal includes primary synchronization signal and secondary synchronization signal.It is synchronized by detection The downstream frequency and time synchronization of signal, UE and base station.Also, since synchronization signal carries Physical Cell Identifier, detection is same Step signal also implies that UE has found LTE/LTE-A cell.

In uplink, when UE has transmitting uplink data, need to initiate random access (Random Access, referred to as RA) carry out uplink synchronous and establish RRC(Radio Resource Control, referred to as RRC) connection, i.e., from the RRC free time (Idle) state enters RRC connection (Connected) state.UE needs to send random access preamble when random access (preamble), network side realizes identification and uplink to UE by detecting random access preamble in specific running time-frequency resource The synchronization of link.

Fig. 4 a is to dispose schematic diagram according to the network of the cellular radio Communication system of the relevant technologies, be can be shown in Fig. 4 a 3GPPLTE/LTE-A system, or other cellular radio Communication technologies.In the access net of cellular radio Communication system, net Network equipment generally comprises a certain number of base stations (base station, or referred to as node B, Node B or the node of evolution B, evolved Node B, eNB, or node B, enhanced the Node B, eNB of enhancing), and other network entities (network entity) or network unit (network element).Alternatively, in short, it in 3 gpp can also be by it It is referred to as network side, i.e. universal terrestrial access network (the Evolved Universal Terrestrial Radio of evolution Access Network, referred to as E-UTRAN).Base station mentioned here also includes the low power nodes (Low in network Power Node, referred to as LPN), such as Femto cell or Home eNodeB (pico, Relay, femto, HeNB, that is, Home ENB etc.).It is simple to describe, three base stations are merely illustrated in Fig. 4 a.Base station provides certain wireless signal coverage area, at this Terminal (terminal, perhaps referred to as UE or referred to as device) in coverage area can be carried out wireless communication with the base station. The wireless signal overlay area of one base station may based on certain criterion be divided into one or more cell (cell) or Sector (sector), such as may be three cells.

In D2D discovery, there is also the time synchronization between similar transmitting terminal UE and receiving end UE, i.e. receiving end is obtained To the transmission timing of corresponding D2D discovery signal, to determine the reception timing of corresponding D2D discovery signal.If it is the D2D of minizone UE is communicated, and it is the resource information that D2D has found signal distribution that receiving end UE, which also needs to obtain adjacent area,.On this basis, it receives D2D discovery signal can be just correctly received in end UE, and solves the content of corresponding D2D discovery signal.

In nonsynchronous network deployment, there are timing offset between different base station, the neighboring community of affiliated different base station When carrying out equipment between UE to device data communication, the D2D from adjacent area is unable to properly receive since timing error will lead to UE It was found that signal.If UE needs to be properly received the D2D discovery signal of adjacent area UE, it is necessary to first know the D2D discovery that adjacent area UE is sent Signal receives timing and the resource allocation information of adjacent area UE.

Embodiment one

In the present embodiment, D2D UE directly detects neighbor synchronization signal and obtains adjacent area D2D resource allocation information i.e. D2D letter Number corresponding resource allocation information.

Fig. 5 is the schematic diagram of the first realization principle of D2D discovery signal communication according to the preferred embodiment of the invention, such as Shown in Fig. 5, Cell51, Cell52 and Cell53 are the cellular cell of corresponding different base station, UE54, UE55 and UE56 difference respectively It is the UE for being subordinate to above three cell, signal 57, signal 58 and signal 59 are respectively the downlink synchronous signal of three cells, signal 510, signal 511 is respectively the downlink synchronous signal of correspondence Cell52 and Cell53 that UE54 can be detected, signal 512 and signal 513 be the corresponding UE 55 that UE54 is received and the D2D discovery signal that UE56 is sent respectively.Wherein, it is small to be equivalent to first by Cell51 Area, Cell53 or Cell52 are equivalent to second community, and the UE54 in Cell51 is equivalent to D2D UE, UE55 or UE56 and is equivalent to UE in two cells.

If network is synchronous deployment, the timing alignment between the corresponding base station of three cells, the downlink of three cells is same The timing reference for walking signal is synchronous.The down-going synchronous that such three UE, that is, UE54, UE55 and UE56 pass through respective serving cell After signal determines transmission timing, the reception timing synchronization naturally of D2D discovery is carried out between three UE, therefore, UE54 directly will be from The downlink timing determination that serving BS is got is that the reception timing of signal is found to the D2D of Cell52 and Cell53, to come It receives the D2D that adjacent area UE such as UE55 and UE56 are sent and finds signal.Also, the D2D resource allocation of three cells is consistent, UE54 root According to this cell D2D resource allocation information, signal is found in the D2D that corresponding resource location receives UE55 and UE56, and solve D2D It was found that signal content.

If network is asynchronous deployment, the timing between the corresponding base station of three cells is misaligned, under three cells There are deviations for the timing reference of line synchronising signal.UE54 will receive the D2D discovery signal that UE55 and UE56 is sent, it is necessary to first determine Corresponding reception timing.In the present embodiment, it is assumed that UE54 can directly detect the downlink synchronous signal of Cell52 and Cell53, Timing is received in such a case, it is possible to determine by way of detecting adjacent area downlink synchronous signal.Specifically, UE54 according to The downlink synchronous signal of Cell52 determines the transmission timing of the discovery signal of the D2D in Cell52, and the D2D of Cell52 is had found to believe Number transmission timing as to Cell52 D2D discovery signal reception timing, with receive the such as UE55 of the UE in Cell52 hair The D2D discovery signal sent.The D2D discovery signal that the UE in Cell53 is sent is determined according to the downlink synchronous signal in Cell53 Reception timing is similar with the above process, and details are not described herein again.

In the case where network is asynchronous deployment, it is determined that after the reception timing of the D2D discovery signal of adjacent area, it is also necessary to The resource allocation information of adjacent area is obtained to receive the D2D of adjacent area and find signal.It determines and receives timing and acquisition resource allocation information There is no points of sequencing, in other embodiments, can also first obtain the resource allocation information of adjacent area, then determine to receive and determine When.There are many kinds of the modes for obtaining resource allocation information, in the present embodiment, by increasing instruction in the broadcast message of base station originally The mode of the corresponding resource allocation information of cell D2D discovery signal obtains.Specifically, Cell51, Cell52, Cell53 institute are right The corresponding resource allocation information of instruction this cell D2D discovery signal is all carried in the broadcast message that the base station answered is sent.UE54 Other than it can detect the broadcast message of this cell Cell51, moreover it is possible to detect the broadcast message of adjacent area Cell52 and Cell53, And the corresponding resource allocation information of D2D discovery signal of adjacent area can be further obtained from the broadcast message of adjacent area.

UE54 is corresponding according to the D2D discovery signal for receiving timing and the different adjacent areas obtained of the determining different adjacent areas of correspondence Resource allocation information receive different adjacent areas D2D discovery signal, and parse D2D discovery signal content.

Embodiment two

In the present embodiment, D2D UE determines that the D2D of adjacent area has found signal by the downlink synchronous signal that adjacent area UE is forwarded Receive timing.

Fig. 6 is the schematic diagram of second of realization principle of D2D discovery signal communication according to the preferred embodiment of the invention, such as Shown in Fig. 6, UE64 cannot detect the downlink synchronous signal of adjacent area, need to be determined according to the downlink synchronous signal that adjacent area UE is forwarded The reception timing of the D2D discovery signal of adjacent area.In Fig. 6, Cell61, Cell62 and Cell63 are corresponding different base station respectively Cellular cell, UE64, UE65 and UE66 are the terminal for being subordinate to above three cell respectively, and signal 67, signal 68 and signal 69 divide Not Wei three cells downlink synchronous signal, signal 610, signal 611 be respectively Cell62 and Cell63 in UE65 and UE66 turn The downlink synchronous signal of hair, signal 612 and 613 are the D2D discovery signal that the UE65 that UE64 is received and UE66 is sent respectively.

Each base station is according to Reference Signal Received Power (the Reference Signal of the UE serving cell reported and adjacent area Receiving Power, abbreviation RSRP) one threshold value of maintenance, and this threshold value is indicated in cell by signaling and is owned UE, UE are adjudicated according to the difference D of the serving cell measured and adjacent cell RSRP, and when D value is less than above-mentioned thresholding, UE just turns Send out the downlink synchronous signal of own base station.

For convenience, below with the resource distribution of D2D discovery signal instruction UE forwarding synchronization signal.The present invention is not It is limited to the communication of D2D discovery signal, is also possible to other D2D discovery signal.Pass-through mode one and pass-through mode described below Second is that two kinds of optional downlink synchronous signal pass-through modes.

Pass-through mode one:

The downlink synchronous signal of forwarding accounts for 6 RB in centre on frequency domain, consistent with the synchronization signal of LTE system.In time domain, The converting downlink synchronization signal in some discovery subframe in discovery resource period.Fig. 7 is forwarding according to an embodiment of the present invention The forwarding resource location exemplary diagram of mode one.In Fig. 7, forwarded in first discovery subframe 71 in each discovery resource period Synchronization signal.As 72,73 do not forward synchronization signal in other discovery subframes.

It forwards in synchronization signal, on the fixed symbol k being mapped in forwarding subframe of PSS, k is OFDM symbol in a subframe Index, value 0~13.

SSS is mapped on other symbol l with the same subframe of PSS (except k, i.e. l ≠ k).Offset between l and k There are determining mapping relations with the D2D discovery signal resource configuration call number M of the forwarding affiliated subdistrict UE.D2D described herein It was found that signal resource configuration call number M has corresponded to distribution in cell (cell i.e. where forwarding UE, be equivalent to second community) To the resource information of D2D discovery signal, different call number M has corresponded to different resource allocation informations.Forward UE according to certain Mapping principle place PSS/SSS respectively, receive after UE detects PSS/SSS, it is same to obtain timing according to certain mapping principle Step and adjacent area discovery resource distribution index M, to obtain the adjacent area D2D discovery specific resource allocation information of signal.

Specifically, when forwarding UE mapping PSS/SSS, first according to predefined k value, PSS is placed on symbol k；Root again It is found that the value of resource distribution call number M obtains the offset l ' of the place PSS and SSS notation index, here M=0~M ' -1, M ≠ 1, M ' it is the positive integer that maximum takes 13, M ≠ 1 is to generate interference in order not to the synchronous search to adjacent area honeycomb UE.Pay attention to here The offset of the notation index is one-way circulation offset, i.e., only takes offset to a direction (as to the left), another The offset in direction is transformed on corresponding cycle offset by way of modulus.As taken cycle offset, l ratio k value to the left Small call number can be obtained directly by k-l, and then-l < 0 k can pass through 14+ for conventional CP to l ratio k big call number (k-l) realizes circulation offset.Therefore there is following corresponding relationship:

L '=k-l (l≤k) (formula 1)

L '=14+ (k-l) (l > k) (formula 2)

Notation index l where notation index k and SSS where the above-mentioned offset l ' and PSS for only illustrating notation index Corresponding relationship.And in the forwarding side UE, it to determine the value of l, then need to obtain l ' according to discovery resource distribution index M, in turn Obtain the value of l.

The corresponding relationship of l ' and M are as follows:

L '=M+1 (formula 3)

By the notation index l of the available SSS mapping of l ', mapping relations are as follows:

L=k-l ' (l '≤k) (formula 4)

L=l ' (l ' > k) (formula 5)

In the reception side UE, after the PSS for detecting forwarding, according to the symbol k value predefined where may know that PSS, and obtain Subframe timing.SSS is detected in same subframe, according to the symbol for the available SSS and PSS of notation index value l for detecting SSS Offset l ', according to formula are as follows:

L '=k-l (l≤k) (formula 6)

L '=14+ (k-l) (l > k) (formula 7)

After obtaining l ', discovery resource distribution index M value in adjacent area can be obtained according to l=l ' -1.It is fixed according to the subframe of acquisition When and the corresponding resource distribution of M, can obtain wireless frame timing and find resource period in other discovery subframe positions.

Fig. 8 is the Mapping Examples of the UE forwarding synchronization signal of corresponding pass-through mode one according to an embodiment of the present invention, 82 and 83 be the mapping position of PSS, and 81 and 84 be the mapping position of SSS.Which show the following two kinds mapping modes:

(1) k=12, l=1, l '=11, M=10；

(2) k=3, l=11, l '=6, M=5；

Pass-through mode two:

Forwarding synchronization signal accounts for 6 RB in centre on frequency domain, consistent with the PSS/SSS of LTE.In time domain, in discovery resource In period, PSS and SSS are all forwarded in the subframe 0 of all radio frames for being corresponding with discovery subframe；In certain special sons containing discovery PSS is only forwarded in the subframe 5 of the radio frames of frame.

Fig. 9 is that one of the resource location of the forwarding synchronization signal of corresponding pass-through mode two according to an embodiment of the present invention shows Example, this example are to forward PSS in the subframe 5 of first radio frames containing discovery subframe in discovery resource period.It corresponds to Fig. 9, in a discovery resource period, 91 and 93 corresponding subframes 0 forward PSS and SSS, 92 5 forwardings of corresponding subframe simultaneously PSS, and 94 corresponding subframes 5 do not forward synchronization signal.

Mapping mode of the PSS/SSS that mode two forwards in a subframe is similar with aforesaid way one.The side UE is being forwarded, PSS is first mapped in the symbol that the index of the subframe 0 of the radio frames containing discovery subframe is k according to predefined fixed form, same In subframe 0, offset l ' is determined according to discovery resource distribution index M, the notation index l of mapping SSS is obtained in conjunction with l ' and k. From M to l ' mapping equation that arrives l again is identical as mode 1.For finding in resource period, in the subframe 5 of corresponding special radio frames, Also according on fixed form identical with subframe 0 mapping PSS to symbol k.Equally, in order not to the synchronous search to adjacent area honeycomb UE Interference is generated, M ≠ 1 is taken.

When in adjacent area, UE obtains reception timing, detecting PSS/SSS if detecting PSS and SSS, it is same can to get frame Step, adjacent area CellId and discovery resource distribution index M, then detect to the radio frames for being found subframe, detect only PSS and Subframe without SSS can determine that start frame is with reference to timing in the period according to its specific position.If first detecting that subframe 5(only has PSS), then start frame reference timing in the period can be directly determined, then has the subframe 0 of PSS/SSS to detect adjacent area by another CellId and resource distribution index M.

Figure 10 be corresponded manner two according to an embodiment of the present invention a UE forwarding synchronization signal Mapping Examples, 102, 103,104 and 106 be PSS mapping position, and 101 and 105 be SSS mapping position.Which show the following two kinds mapping modes:

(1) k=12, l=1, l '=11, M=10；

(2) k=3, l=12, l '=5, M=4；

Wherein, k is the notation index of PSS mapping, and l is the notation index of SSS mapping, and l ' is offset, i.e. PSS and SSS Notation index difference, M be D2D find resource distribution index.

Embodiment three

In the present embodiment, D2D UE forwards the downlink synchronous signal of adjacent area to obtain adjacent area by the UE in this cell Downlink synchronous signal, and then determine the reception timing of the D2D discovery signal of adjacent area.

Figure 11 is the schematic diagram of the third realization principle of D2D discovery signal communication according to the preferred embodiment of the invention, As shown in figure 11, UE113 can detecte the downlink synchronous signal to adjacent area Cell111 and Cell112, and UE114 cannot be detected To the downlink synchronous signal of adjacent area Cell111 and Cell112.

UE113 corresponded in its corresponding serving cell forwarded respectively in uplink time/frequency source adjacent area Cell111 and The downlink synchronous signal of Cell112, forward signal are only to mark a forward signal in figure, but be not intended to limit 1114 in figure The signal number of UE113 forwarding.For the downlink synchronous signal of each adjacent area of forwarding, the resource location and PSS/ of forward signal The mapping mode of SSS can choose the method in mode one or mode two in embodiment two.It is corresponding same but for each adjacent area The period of step signal forwarding may become larger, such as: becoming original N times, N is the adjacent area number that UE113 will forward synchronization signal, In the present embodiment, N=2.

Each base station increases the resource allocation information of instruction this cell D2D discovery signal in broadcast message, and UE113 passes through inspection The broadcast message of adjacent area Cell111 and Cell112 are surveyed, the corresponding resource allocation information of D2D discovery signal of corresponding adjacent area is obtained, And the D2D resource allocation information of adjacent area can be shared with other UE in cell.For example, can be by following two mode It is any that the D2D resource allocation information of adjacent area is shared with other UE in this cell:

Mode 1: according to certain mapping method, the neighbor synchronization signal of UE113 forwarding carries the D2D discovery of corresponding adjacent area The corresponding resource allocation information of signal, certain mapping method can be mapping method described in embodiment two.

Mode 2: if UE113 is RRC connection (RRC_Connected) state, the D2D resource allocation of adjacent area can be believed Breath is reported to serving BS, and base station is corresponding by the D2D discovery signal of adjacent area by the way that in signaling, carrying indicates information such as in broadcast Resource allocation information is indicated to other UE in cell.

UE114 is obtained from the downlink synchronous signal of the adjacent area Cell111 and Cell112 forwarded of the UE113 in same cell The transmission timing of the D2D discovery signal of corresponding adjacent area, determines connecing for the D2D discovery signal of corresponding adjacent area Cell111 and Cell112 Timing is received, while the corresponding money of D2D discovery signal of 1 or the acquisition of mode 2 adjacent area Cell111 and Cell112 through the above way Information is distributed in source.Timing is received according to the D2D discovery signal determined and D2D resource allocation information in adjacent area receives and parses through out adjacent area D2D has found the content of signal, and the D2D sent such as UE115 has found signal 1113.

Example IV

In the present embodiment, other UE are calculated in this cell of D2D UE and the timing of reporting neighboring cell and the affiliated subdistrict D2D UE is inclined Shifting amount, base station calculate the standard deviation amount of adjacent area according to the timing offset that other UE are reported, and will be under standard offset Issue D2D UE.

Figure 12 is the schematic diagram of the 4th kind of realization principle of D2D discovery signal communication according to the preferred embodiment of the invention, As shown in figure 12, Cell120, Cell121 and Cell122 are the cellular cell of corresponding different base station respectively, and UE123, UE124 are subordinate to Belong to Cell120, UE125 and UE126 and is subordinate to Cell121 and Cell122 respectively.UE123 can detect adjacent area Cell121 and The downlink synchronous signal 1211 and 1212 of Cell122 obtains the downlink timing of adjacent area Cell121 and Cell122.And UE124 is not It can detect the downlink synchronous signal of adjacent area Cell121 and Cell122.

UE123 can obtain the downlink timing of serving cell according to the downlink synchronous signal 128 of serving cell Cell120, And the timing offset δ T of serving cell Cell120 Yu adjacent area Cell121 and Cell122 are respectively obtained by calculating.It is in Adjacent area CellId and corresponding δ T are reported to the corresponding base station serving cell Cell120 i.e. by the UE of RRC_Connected state Serving BS.Serving BS according to different UE(may more than UE123 report) the δ T of each adjacent area that reports, determined by default principle The standard deviation amount of corresponding adjacent area, is named as δ T ', it should be noted that naming standard offset herein is intended merely to facilitate this Description in embodiment, does not limit the invention.The standard deviation of adjacent area Cell121 and Cell122 can be obtained in this way Shifting amount δ T₁₂₁' and δ T₁₂₂'.For above-mentioned default principle, it is preferred that the default principle may include: to take to reach earliest to receive The corresponding timing offset of the timing of UE, or take the average value of the timing offset of all same adjacent areas reported.

Serving BS such as broadcast carrying instruction information by signaling, be in cell all UE indicate adjacent area Cell121 with The standard deviation amount δ T of Cell122₁₂₁' and δ T₁₂₂'.For UE124, although cannot be directly obtained adjacent area Cell121 and The downlink timing of Cell122, but the instruction information that can be issued according to serving BS is received, obtain corresponding adjacent area Cell121 With the standard deviation amount δ T of Cell122₁₂₁' and δ T₁₂₂'.Meanwhile it being obtained according to the downlink synchronous signal of serving cell Cell120 127 Take the downlink timing T1 of serving BS.It, can be true by compensating the standard deviation amount of adjacent area on the basis of serving cell timing Determine the timing of adjacent area.For example T1+ δ T is used respectively₁₂₁' and T1+ δ T₁₂₂' determine adjacent area Cell121 and Cell122 downlink timing, Reception timing as the D2D discovery signal for receiving adjacent area Cell121 and Cell122.

UE123 can obtain the D2D of adjacent area by detection adjacent area broadcast message according to the criterion of mode 2 in embodiment three It was found that the corresponding resource allocation information of signal, and the corresponding resource allocation information of the D2D of adjacent area discovery signal is reported to service The resource allocation information is indicated to other UE in cell by carrying instruction information in signaling such as broadcast by base station, base station.

In this way, UE124 can be according to the determining adjacent area D2D for receiving timing and get to adjacent area D2D discovery signal Resource allocation information receives and solves the content of adjacent area D2D discovery signal, and the D2D sent such as UE125 has found signal 1215.

Embodiment five

The present embodiment illustrates the acquisition of the corresponding resource allocation information of D2D discovery signal so that D2D has found signal as an example.For This cell D2D has found that obtaining for the corresponding resource allocation information of signal can indicate to realize by the signaling of serving BS, service The indication signaling of base station can be the existing signaling of LTE system, can also newly define signaling to indicate.Adjacent area D2D is had found to believe The acquisition of number resource analysis information is described in above-described embodiment one into example IV, and the present embodiment further carries out it Description.

Figure 13 is D2D signal communication structural schematic diagram according to an embodiment of the present invention, as shown in figure 13, UE133 and UE134 The corresponding resource allocation information of D2D discovery signal is obtained from the broadcast message SIB2 that Cell130 own base station issues, in resource It distributes in the corresponding resource of information and sends D2D discovery signal.Equally, UE135 and UE136 is respectively from Cell131 and Cell132 institute Belong to and obtain D2D discovery signal resource distribution information in the broadcast message SIB2 that base station issues, D2D discovery is sent in corresponding resource Signal.

The acquisition of resource allocation information corresponding for adjacent area D2D discovery signal, may be implemented, this implementation there are many method In example, as shown in figure 13, illustrated using Cell130 as serving cell, wherein Cell130 is equivalent to first community, Cell131 Second community is equivalent to Cell132.

Method 1: it is consistent with embodiment one, synchronizing network is disposed, UE133 and UE134 have found to believe according to this cell D2D Number resource allocation information find signal to receive the D2D that UE in adjacent area Cell131 and Cell132 is sent；For non-synchronous network Network deployment, the D2D that UE133 obtains adjacent area by directly detecting the broadcast message of adjacent area Cell131 and Cell132 have found signal pair The resource allocation information answered.

Method 2: consistent with embodiment two, UE134 passes through the downlink synchronous signal of the adjacent area of parsing UE135 forwarding, according to The mapping mode of PSS and SSS obtains the corresponding resource allocation information of D2D discovery signal of adjacent area Cell131.

Method 3: consistent with embodiment three, UE134 is believed by parsing the down-going synchronous of the adjacent area of the UE133 forwarding of this cell Number, the corresponding resource allocation of D2D discovery signal of adjacent area Cell131 and Cell132 are obtained according to the mapping mode of PSS and SSS Information；

Method 4: consistent with example IV, UE134 obtains adjacent area by the signaling that the base station of serving cell Cell130 issues The corresponding resource allocation information of D2D discovery signal of Cell131 and Cell132, the corresponding resource point of D2D discovery signal of adjacent area It is that the broadcast message for detecting adjacent area Cell131 and Cell132 by UE133 is got with information.The money that UE133 will test Information reporting is distributed to the base station of Cell130 in source.Alternatively, the corresponding resource allocation information of D2D discovery signal of adjacent area can be with Obtain in the following manner: the base station of Cell130 by X2 interface or non-standard interface respectively with adjacent area Cell131 and The base station interaction of Cell132 obtains the corresponding resource allocation information of D2D discovery signal；

Method 5: UE135 forwards the corresponding resource allocation letter of D2D discovery signal of cell Cell131 in the Cell131 of adjacent area Breath, UE134 have found the corresponding resource allocation information of signal by the D2D that the forward signal of UE135 obtains adjacent area Cell131.

Embodiment six

The present embodiment solves in nonsynchronous network deployment, realizes that D2D discovery signal is logical between the neighboring community of different base station Letter.The method that D2D discovery signal communication is realized in the present embodiment may include: to obtain transmission timing and the adjacent area of adjacent area UE The resource allocation information of UE realizes the reception to adjacent area D2D discovery signal, and correctly solves the D2D discovery signal of adjacent area.Its In, adjacent area is equivalent to second community, and the cell where receiving the user equipment of D2D discovery signal is first community.

Specifically: the affiliated subdistrict D2D UE is reference cell, that is, first community, and adjacent area is with reference cell not same The neighboring community of eNB, D2D UE get the transmission timing of adjacent area D2D discovery signal according to predefined criterion, according to this hair Timing is sent to receive adjacent area D2D discovery signal；D2D UE obtains the resource allocation of adjacent area D2D UE according still further to predefined criterion Information receives adjacent area D2D in the corresponding resource of this resource allocation information and finds signal；It completes to connect adjacent area D2D discovery signal It receives, and solves the D2D discovery signal of the adjacent area received.

Above-mentioned acquisition adjacent area D2D has found that the criterion of the transmission timing of signal includes:

(1) adjacent area UE forwards downlink synchronous signal PSS/SSS, the D2D UE detection adjacent area UE forwarding of adjacent area respective base station Downlink synchronous signal obtains adjacent area D2D UE transmission timing；

(2) D2D UE gets the transmission of adjacent area D2D UE by the downlink synchronous signal PSS/SSS of directly detection adjacent area Periodically；

(3) the D2D UE for directly detecting adjacent area downlink synchronous signal PSS/SSS is forwarded under adjacent area in affiliated subdistrict Line synchronising signal PSS/SSS, other D2D UE that can not directly detect adjacent area downlink synchronous signal are small by detecting in cell The adjacent area downlink synchronous signal of other UE forwarding obtains the D2D UE transmission timing of adjacent area in area；

(4) serving BS in X2 mouthfuls or non-standard interface interaction or serving cell by that can directly detect under adjacent area The feedback ratio of the UE of line synchronising signal PSS/SSS as above reports acquisition of information adjacent area timing information, and D2D UE is obtained by serving BS Take adjacent area timing information.

Above-mentioned acquisition adjacent area D2D has found that the criterion of the corresponding resource allocation information of signal includes:

(1) it is configured by the different mappings of the PSS and SSS that are forwarded to adjacent area UE, to carry the resource allocation of adjacent area UE Information after D2D UE detects the PSS and SSS of adjacent area UE forwarding, obtains the resource of adjacent area UE according to different mapping configurations Distribute information；

(2) increase the instruction information to the corresponding resource allocation information of D2D discovery signal in the broadcast message of adjacent area, D2D UE obtains the resource allocation information of adjacent area UE by parsing adjacent area broadcast message；

(3) D2D UE obtains the corresponding resource allocation information of adjacent area D2D discovery signal from the base station of affiliated subdistrict；

(4) adjacent area UE directly forwards the corresponding resource allocation information of adjacent area D2D discovery signal.

Obviously, those skilled in the art should be understood that each module of the above invention or each step can be with general Computing device realize that they can be concentrated on a single computing device, or be distributed in multiple computing devices and formed Network on, optionally, they can be realized with the program code that computing device can perform, it is thus possible to which they are stored It is performed by computing device in the storage device, and in some cases, it can be to be different from shown in sequence execution herein Out or description the step of, perhaps they are fabricated to each integrated circuit modules or by them multiple modules or Step is fabricated to single integrated circuit module to realize.In this way, the present invention is not limited to any specific hardware and softwares to combine.

The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention, for the skill of this field For art personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, made any to repair Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.

Claims (22)

1. a kind of communication means of device-to-device D2D, which is characterized in that the described method includes:

D2D user equipment (UE) in first community determines the reception timing to the D2D discovery signal of second community, and described in acquisition D2D has found the corresponding resource allocation information of signal；

The D2D UE receives the D2D according to the reception timing and the resource allocation information and finds signal；

Wherein, the D2D UE determines that the reception timing to the D2D discovery signal of the second community includes: the D2D UE detect at least one UE in the second community forwarding the second community downlink synchronous signal, wherein it is described extremely A few UE is determined according to the Reference Signal Received Power RSRP or timing advance TA of the UE in the second community；It is described D2D UE determines the transmission timing of D2D discovery signal according to the detected downlink synchronous signal, and by the hair Sending timing determination is the reception timing.

2. the method according to claim 1, wherein the D2D UE is determined to described in the second community D2D has found that the reception timing of signal includes:

The D2D UE detects the downlink synchronous signal of the second community；

The D2D UE determines the transmission timing of the D2D discovery signal according to the detected downlink synchronous signal, and The transmission timing is determined as the reception timing.

3. the method according to claim 1, wherein at least one described UE is according in the second community What the RSRP or TA of UE were determined includes:

At least one described UE is that the second community own base station determines UE corresponding described first in the second community After difference between cell RSRP and the second community RSRP, the maximum M UE of the difference is selected to obtain, wherein institute Stating M is positive integer；Or

At least one described UE is choosing after the respective TA value of UE that the second community own base station obtains in the second community Select what the maximum N number of UE of the TA value was obtained, wherein the N is positive integer.

4. the method according to claim 1, wherein the D2D UE is determined to described in the second community D2D has found that the reception timing of signal includes:

The D2D UE detects the downlink synchronous signal of the second community of other UE forwarding in the first community, wherein Other described UE are the UE that the downlink synchronous signal of the second community is able to detect that in the first community；

The D2D UE determines the transmission timing of the D2D discovery signal according to the detected downlink synchronous signal, and The transmission timing is determined as the reception timing.

5. the method according to claim 1, wherein the D2D UE is determined to described in the second community D2D discovery signal receives timing and includes:

The D2D UE receives the instruction message of the D2D UE own base station, wherein the instruction message carries described The timing information of two cells；

The D2D UE determines the reception timing according to the timing information.

6. according to the method described in claim 5, it is characterized in that, the timing information is obtained by way of at least one of It takes:

It is interactive from described second by the X2 interface between the first community own base station and the second community own base station Cell own base station obtains；

Pass through the radio open or non-standard interface between the first community own base station and the second community own base station It is obtained from the second community own base station；

By being able to detect that the reporting in information for UE of the downlink synchronous signal of the second community is obtained in the first community It takes.

7. according to the method described in claim 5, it is characterized in that, the timing information of the second community includes: according to The standard for the second community that the timing offset for the first community that at least one UE in first community is reported determines Offset, wherein the timing offset is under downlink synchronous signal and the second community according to the first community What line synchronising signal obtained.

8. the method according to claim 1, wherein obtaining the corresponding resource point of the D2D discovery signal Include: with information

The D2D UE detects the broadcast message of the second community；

The D2D UE obtains the resource allocation information from the broadcast message.

9. the method according to claim 1, wherein obtaining the corresponding resource point of the D2D discovery signal Include: with information

The D2D UE detects the downlink synchronous signal of the second community of the forwarding of at least one UE in the second community, Wherein, at least one described UE is determined according to the RSRP or TA of the UE in the second community；

The D2D UE exists according to the primary synchronization signal PSS and secondary synchronization signal SSS of the detected downlink synchronous signal The different location mapped respectively in forwarding subframe, obtains the resource allocation information.

10. the method according to claim 1, wherein obtaining the corresponding resource point of the D2D discovery signal Include: with information

The D2D UE detects the downlink synchronous signal of the second community of other UE forwarding in the first community, wherein Other described UE are the UE that the downlink synchronous signal of the second community is able to detect that in the first community；

The D2D UE exists according to the primary synchronization signal PSS and secondary synchronization signal SSS of the detected downlink synchronous signal The different location mapped respectively in forwarding subframe, obtains the resource allocation information.

11. the method according to claim 1, wherein obtaining the corresponding resource point of the D2D discovery signal Include: with information

The D2D UE receives the instruction message of the D2D UE own base station, wherein the instruction message carries the money Information is distributed in source；

The D2D UE obtains the resource allocation information from the instruction message.

12. according to the method for claim 11, which is characterized in that the resource allocation letter carried in the instruction message Breath is got by way of at least one of:

It is interactive from described second by the X2 interface between the first community own base station and the second community own base station Cell own base station obtains；

Pass through the radio open or non-standard interface between the first community own base station and the second community own base station Interaction is obtained from the second community own base station；

By being able to detect that the UE of the resource allocation information of the second community reports information in the first community Middle acquisition；

It is obtained by upper layer network interaction from the second community own base station, wherein the upper layer network is above the base It stands the Web communication layer of layer.

13. the method according to claim 1, wherein obtaining the corresponding resource point of the D2D discovery signal It include: the resource allocation information for receiving the UE of the second community and directly forwarding with information.

14. a kind of user equipment (UE), the UE is under the jurisdiction of first community characterized by comprising

Determining module, for determining the reception timing to the D2D discovery signal of second community；

Module is obtained, for obtaining the corresponding resource allocation information of the D2D discovery signal；

Receiving module finds signal for receiving the D2D according to the reception timing and the resource allocation information；

Wherein, the determining module includes: detection unit, for detecting the institute of the forwarding of at least one UE in the second community State the downlink synchronous signal of second community, wherein at least one described UE is believed according to the reference of the UE in the second community Number receive what power RSRP or timing advance TA were determined；Determination unit, for according to the detected downlink synchronous signal It determines the transmission timing of the D2D discovery signal, and the transmission timing is determined as the reception timing.

15. UE according to claim 14, which is characterized in that the determining module includes:

Detection unit, for detecting the downlink synchronous signal of the second community；

Determination unit, for determining the transmission timing of the D2D discovery signal according to the detected downlink synchronous signal, And the transmission timing is determined as the reception timing.

16. UE according to claim 14, which is characterized in that the determining module includes:

Detection unit, for detecting the downlink synchronous signal for the second community that other UE are forwarded in the first community, In, other described UE are the UE that the downlink synchronous signal of the second community is able to detect that in the first community；

Determination unit, for determining the transmission timing of the D2D discovery signal according to the detected downlink synchronous signal, And the transmission timing is determined as the reception timing.

17. UE according to claim 14, which is characterized in that the determining module includes:

Detection unit, for receiving the instruction message of the D2D UE own base station, wherein the instruction message carries described The timing information of second community；

Determination unit, for determining the reception timing according to the timing information.

18. UE according to claim 14, which is characterized in that the acquisition module includes:

Resources measurement unit, for detecting the broadcast message of the second community；

Acquiring unit, for obtaining the resource allocation information from the broadcast message.

19. UE according to claim 14, which is characterized in that the acquisition module includes:

Resources measurement unit, it is same for detecting the downlink of the second community of the forwarding of at least one UE in the second community Walk signal, wherein at least one described UE is determined according to the RSRP or TA of the UE in the second community；

Acquiring unit, for being existed according to the primary synchronization signal PSS and secondary synchronization signal SSS of the detected downlink synchronous signal The different location mapped respectively in forwarding subframe, obtains the resource allocation information.

20. UE according to claim 14, which is characterized in that the acquisition module includes:

Resources measurement unit, for detecting the down-going synchronous letter for the second community that other UE are forwarded in the first community Number, wherein other described UE are the downlink synchronous signals that the second community is able to detect that in the first community UE；

Acquiring unit, for the primary synchronization signal PSS and secondary synchronization signal SSS according to the detected downlink synchronous signal The different location mapped respectively in forwarding subframe, obtains the resource allocation information.

21. UE according to claim 14, which is characterized in that the acquisition module includes:

Resources measurement unit, for receiving the instruction message of the D2D UE own base station, wherein the instruction message carries The resource allocation information；

Acquiring unit, for obtaining the resource allocation information from the instruction message.

22. UE according to claim 14, which is characterized in that the acquisition module includes: acquiring unit, for receiving State the resource allocation information that the UE of second community is directly forwarded.