CN104735774B

CN104735774B - A kind of air interface synchronization method and device based on networking

Info

Publication number: CN104735774B
Application number: CN201510127870.XA
Authority: CN
Inventors: 朱宏
Original assignee: Comba Telecom Technology Guangzhou Ltd; Comba Telecom Systems China Ltd; Comba Telecom Systems Guangzhou Co Ltd; Tianjin Comba Telecom Systems Co Ltd
Current assignee: Comba Network Systems Co Ltd
Priority date: 2015-03-23
Filing date: 2015-03-23
Publication date: 2018-05-01
Anticipated expiration: 2035-03-23
Also published as: CN104735774A

Abstract

The invention discloses a kind of air interface synchronization method and device based on networking, to solve the problems, such as that the air interface synchronization precision between base station in the prior art is relatively low.This method is, when reaching each synchronizing cycle, the base station in networking determines offset synchronization time of itself according to the synchronization level of itself；According to offset synchronization time of itself, determine itself intercepts subframe and synchronous subframe；Pass through the synchronizing signal intercepted subframe and obtain target BS of itself, the Reference BTS of the base station is determined from target BS based on the synchronizing signal, and the synchronizing signal based on the Reference BTS establishes air interface synchronization with the Reference BTS, so, the information source of high synchronization level can be searched for automatically, change the synchronization level of base station in real time, improve the synchronization accuracy of base station, the synchronization level for being optimal each base station, avoiding respective base stations from exception occur causes whole network step-out, so as to improve the synchronous self-healing ability of whole network.

Description

A kind of air interface synchronization method and device based on networking

Technical field

The present invention relates to moving communicating field, more particularly to a kind of air interface synchronization method and device based on networking.

Background technology

With the fast development of mobile Internet, various applications emerge in an endless stream, to the capacity of mobile network, the requirement handled up It is higher and higher.Commercial 4G networks are often operated in high band at present, and with original 2G, 3G frequency ranges are compared, and signal attenuation is faster, right The penetration performance of building is worse, carries out in-door covering by outdoor grand net, effect is often bad.With micro-base station (FemtoCell) form a complete network as elementary cell and be increasingly becoming a ripe solution.

But if can not keep reliable synchronization between each FemtoCell, mutual interference can be very serious, right The capacity and user experience of whole system cause very detrimental effect.

In view of the above-mentioned problems, the prior art proposes air interface synchronization technology, i.e., the base station that need to be synchronized is by intercepting The synchronizing signal that base station through completing synchronization is sent is adjusted in itself to obtain synchronizing information according to the synchronizing information of acquisition Portion's clock, can thus be synchronized with it is above-mentioned completed synchronous base station, it is above-mentioned at this time to have completed synchronous base station as be into The Reference BTS of the synchronous base station of row.

But the method for traditional multihop synchronization is that the synchronization level of each base station is determined in the start-up course of base station, if in Between the base station of level-one there is step-out, then the base station of next stage can not keep synchronous regime, or must interrupting service for a period of time To reaffirm synchronization level and obtain synchronous.

In addition, traditional multihop synchronous method when high level synchronization information source occurs can not adaptive synchronicity to high-grade letter Source, either needs to switch or needs interrupting service, can just be synchronized to high-grade information source, synchronization accuracy is poor, poor user experience.

The content of the invention

The object of the present invention is to provide a kind of air interface synchronization method and device based on networking, to solve base in the prior art The problem of air interface synchronization precision between standing is relatively low.

The purpose of the present invention is what is be achieved through the following technical solutions：

A kind of air interface synchronization method based on networking, including：

When reaching each synchronizing cycle, the base station in networking determines the same of itself according to the synchronization level of itself Walk time offset；

According to offset synchronization time of itself, determine itself intercepts subframe and synchronous subframe for one base station；

One base station by itself intercept subframe obtain target BS synchronizing signal, based on the synchronizing signal from The Reference BTS of a base station, and the synchronizing signal based on the Reference BTS and the benchmark are determined in the target BS Air interface synchronization is established in base station, wherein what the synchronizing signal was sent for the target BS by the synchronous subframe of itself, it is described Target BS is the base station higher than the synchronization level of a base station.

In such manner, it is possible to make whole network complete automatic network-building, and search for the information source of high synchronization level automatically in networking, Change the synchronization level of base station in real time, i.e., the clock grade of a certain base station changes during networking, also can be again adaptive Answer this change, it is not necessary to interrupt regular traffic and be adapted to the synchronization level of oneself with regard to that can find each base station, complete whole net The synchronization of network, the synchronization level for being optimal each base station, avoiding respective base stations from exception occur causes whole network step-out, from And improve the synchronous self-healing ability of whole network.

Optionally, further comprise：

In the pre-configured stage, a base station carries out global position system GPS synchronization, the synchronizations of IEEE 1588 and sky successively Mouth is synchronous；

If a base station is synchronous by GPS or 1588 mode completion timings of IEEE, the synchronization level of a base station To be secondary high-grade.Wherein, the synchronization level of macro base station is highest ranking；

If a base station is synchronous by air interface synchronization mode completion timing, according to the Reference BTS of a base station Synchronization level, determines the synchronization level of a base station, wherein, the synchronization level of macro base station is highest ranking, if the benchmark Base station is macro base station, then the synchronization level of a base station is described if the Reference BTS is non-macro base station to be secondary high-grade The synchronization level of an one base station grade lower than the synchronization level of the Reference BTS；

If a base station can not complete synchronization, it is determined that a base station is isolated island base station, the isolated island base station it is same Step grade is the lowest class.

Optionally, a base station determines offset synchronization time of itself according to the synchronization level of itself, including：

One base station using systemic presupposition synchronization level with synchronization time offset mapping relations according to itself Synchronization level, determines offset synchronization time of itself.

Optionally, according to offset synchronization time of itself, determine itself intercepts subframe and same step for a base station Frame, including：

Offset and the mapping relations of radio frames are intercepted according to itself in one base station using the synchronization time of systemic presupposition Offset synchronization time, determine itself intercepts radio frames, and the subframe 1 for intercepting radio frames of itself is arranged to the same of itself Step frame, wherein, a base station is dispatched in the synchronous subframe of itself without data service, and non-isolated island base station is in synchronous subframe The 3rd symbol send subframe 0 auxiliary synchronous signals SSS and skip master sync signal PSS occupancy resource block RB, isolated island base Stand synchronous subframe the 3rd symbol send son 5 auxiliary synchronous signals SSS and skip master sync signal PSS occupancy resource block RB；

Subframe is intercepted by what the synchronous subframe of the target BS higher than itself synchronization level was arranged to itself in one base station.

Optionally, a base station by itself intercept subframe obtain target BS synchronizing signal, including：

One base station at itself by intercepting the synchronous letter for not sending downlink signal in subframe to obtain target BS Number, the synchronizing signal of the target BS includes master sync signal PSS and auxiliary synchronous signals SSS, the synchronization of the target BS Signal is sent for target BS by the synchronous subframe of itself.

Optionally, a base station is by the synchronizing signal intercepted subframe and obtain target BS of itself, based on described same Walk signal from the target BS determine a base station Reference BTS, and the synchronizing signal based on the Reference BTS with The Reference BTS establishes air interface synchronization, including：

One base station is by the synchronizing signal intercepted subframe and obtain target BS of itself, the synchronization letter based on acquisition Number, determine the corresponding reference signal quality of target BS, obtain the reference signal quality of all target BS；

The reference signal quality of one base station based on all target BS, selects a target base from all target BS The Reference BTS stood as a base station；

One base station obtains the synchronizing signal of the Reference BTS, is built based on the synchronizing signal and the Reference BTS Vertical air interface synchronization.

Optionally, the reference signal quality of the base station based on all target BS, selects from all target BS Reference BTS of one target BS as a base station, specifically includes：

If detect the reference signal quality of a target BS more than default in the base station continuous N synchronizing cycle Threshold value and the synchronization level of a target BS than a base station synchronization level at least high two grades when, by described one Reference BTS of the target BS as a base station；Otherwise, selection one is more same than a base station from all target BS The target BS of the high grade of grade is walked as Reference BTS.

Optionally, a base station obtains the synchronizing signal of the Reference BTS, based on the synchronizing signal and the base Quasi- base station is established after air interface synchronization, is further comprised：

One base station obtains the synchronization level of the Reference BTS, if the synchronization level of the Reference BTS is than described one During the high grade of the synchronization level of base station, then keep the synchronization level of a base station constant；If the Reference BTS is same Walk grade than a base station synchronization level at least tall person's two-stage when, then the synchronization level of a base station is adjusted to than institute State the low level-one of synchronization level of Reference BTS.

If a base station cannot detect the Reference BTS of a base station in continuous N synchronizing cycle, under When one synchronizing cycle reaches, synchronous subframe of the base station in the base station of each synchronization level intercepts synchronizing signal, judges Whether the synchronizing signal of at least one base station can be got in continuous N synchronizing cycle；

If a base station can not get the synchronizing signal of at least one base station, institute in continuous N synchronizing cycle The auxiliary synchronous signals that a base station sends subframe 5 in the synchronous subframe of itself are stated, determine that itself is isolated island base station, adjusts the same of itself Step grade is the lowest class；

If a base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, it is based on The synchronizing signal of at least one base station got, determines the corresponding reference signal quality at least one base station, obtains all Reference signal quality, filters out at least reference signal quality for meeting preset condition from all reference signal qualities, from The highest base station of a synchronization level is selected to be carried out as Reference BTS in the corresponding base station of an at least reference signal quality empty Mouth is synchronous, and it is a grade lower than the synchronization level of the Reference BTS to adjust the synchronization level of itself.

Optionally, if a base station can get the synchronous letter of at least one base station in continuous N synchronizing cycle Number, based on the synchronizing signal of at least one base station got, determine the corresponding reference signal quality at least one base station, obtain All reference signal qualities, filter out at least reference signal matter for meeting preset condition from all reference signal qualities Amount, selects the highest base station of a synchronization level to carry out air interface synchronization from the corresponding base station of an at least reference signal quality, Including：

If a base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, it is based on The synchronizing signal of at least one base station got, determines the corresponding reference signal quality at least one base station, obtains all Reference signal quality, the reference signal quality that isolated island base station is filtered out from all reference signal qualities obtain remaining reference Signal quality, filters out at least reference signal that reference signal quality is more than predetermined threshold value from remaining reference signal quality Quality, selects the highest base station of a synchronization level as Reference BTS from the corresponding base station of an at least reference signal quality Carry out air interface synchronization.

A kind of air interface synchronization device based on networking, positioned at base station side, including：

First determination unit, for when reaching each synchronizing cycle, according to the synchronization level of this base station, determining this base Offset synchronization time stood；

Second determination unit, for offset synchronization time according to this base station, determine this base station intercepts subframe and same Step frame；

Synchronization unit, for the synchronizing signal intercepted subframe and obtain target BS by this base station, based on the synchronization Signal determines the Reference BTS of this base station, and the synchronizing signal based on the Reference BTS and the base from the target BS Air interface synchronization is established in quasi- base station, wherein what the synchronizing signal was sent for the target BS by the synchronous subframe of itself, institute It is the base station higher than the synchronization level of this base station to state target BS.

Optionally, the synchronization unit is further used for：

In the pre-configured stage, synchronous global position system GPS, 1588 synchronizations of IEEE and air interface synchronization are carried out successively；

If this base station is synchronous by GPS or 1588 mode completion timings of IEEE, it is determined that the synchronization level of this base station is secondary It is high-grade.Wherein, the synchronization level of macro base station is highest ranking；

If this base station is synchronous by air interface synchronization mode completion timing, according to synchronization of the Reference BTS of this base station etc. Level, determines the synchronization level of this base station, wherein, the synchronization level of macro base station is highest ranking, if the Reference BTS is grand base To stand, then the synchronization level of this base station is secondary high-grade, if the Reference BTS is non-macro base station, the synchronization level ratio of this base station The low grade of synchronization level of the Reference BTS；

If this base station can not complete synchronization, it is determined that this base station is isolated island base station, and the synchronization level of the isolated island base station is The lowest class.

Optionally, according to the synchronization level of this base station, when determining offset synchronization time of this base station, described first determines Unit is specifically used for：

Synchronization level using the synchronization level of systemic presupposition with the mapping relations of offset synchronization time according to this base station, Determine offset synchronization time of this base station.

Optionally, according to offset synchronization time of this base station, when intercepting subframe and synchronous subframe of this base station, institute are determined The second determination unit is stated to be specifically used for：

Using systemic presupposition synchronization time offset with intercept the mapping relations of radio frames according to this base station it is synchronous when Between offset, determine this base station intercepts radio frames, and the subframe 1 for intercepting radio frames of this base station is arranged to the synchronization of this base station Subframe, wherein, any one base station is dispatched in the synchronous subframe of itself without data service, and non-isolated island base station is in synchronous subframe 3rd symbol sends the auxiliary synchronous signals SSS of subframe 0 and skips the resource block RB of master sync signal PSS occupancy, isolated island base station The auxiliary synchronous signals SSS of son 5 is sent in the 3rd symbol of synchronous subframe and skips the resource block of master sync signal PSS occupancy RB；

Subframe is intercepted by what the synchronous subframe of target BS than this base station synchronization higher grade was arranged to this base station.

When optionally, by the synchronizing signal for intercepting subframe acquisition target BS of this base station, the synchronization unit is specific For：

By downlink signal not sent in subframe obtaining the synchronizing signal of target BS, the mesh in intercepting for this base station The synchronizing signal of mark base station includes master sync signal PSS and auxiliary synchronous signals SSS, and the synchronizing signal of the target BS is target Base station is sent by the synchronous subframe of itself.

Optionally, by this base station intercept subframe obtain target BS synchronizing signal, based on the synchronizing signal from The Reference BTS of this base station, and the synchronizing signal based on the Reference BTS and the Reference BTS are determined in the target BS When establishing air interface synchronization, the synchronization unit is specifically used for：

By the synchronizing signal intercepted subframe and obtain target BS of this base station, the synchronizing signal based on acquisition, determines mesh The corresponding reference signal quality in base station is marked, obtains the reference signal quality of all target BS；

Based on the reference signal quality of all target BS, a target BS is selected to be used as this base from all target BS The Reference BTS stood；

The synchronizing signal of the Reference BTS is obtained, is established and is eated dishes without rice or wine together based on the synchronizing signal and the Reference BTS Step.

Optionally, the reference signal quality based on all target BS, selects a target BS from all target BS During Reference BTS as this base station, the synchronization unit is specifically used for：

If this base station continuous N detects that the reference signal quality of a target BS is more than default threshold value in synchronizing cycle And the synchronization level of this base station of synchronization level of a target BS at least high two grades when, by a target BS make For the Reference BTS of this base station；Otherwise, a grade higher than the synchronization level of this base station is selected from all target BS Target BS is as Reference BTS.

Optionally, the synchronizing signal of the Reference BTS is obtained, is established based on the synchronizing signal and the Reference BTS After air interface synchronization, the synchronization unit is further used for：

The synchronization level of the Reference BTS is obtained, if the synchronization level of the Reference BTS is than the synchronization level of this base station During a high grade, then keep the synchronization level of this base station constant；If the synchronization level of the Reference BTS is more same than this base station Walk grade at least tall person's two-stage when, then the synchronization level of this base station is adjusted to lower than the synchronization level of the Reference BTS one Level.

If this base station cannot detect the Reference BTS of this base station in continuous N synchronizing cycle, in next synchronization When cycle reaches, the synchronous subframe in the base station of each synchronization level intercepts synchronizing signal, and judging whether can be same in continuous N The synchronizing signal of at least one base station is got in step period；

If this base station can not get the synchronizing signal of at least one base station in continuous N synchronizing cycle, in this base The synchronous subframe stood sends the auxiliary synchronous signals of subframe 5, and it is isolated island base station to determine this base station, and the synchronization level for adjusting this base station is The lowest class；

If this base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, based on acquisition The synchronizing signal at least one base station arrived, determines the corresponding reference signal quality at least one base station, obtains all references Signal quality, filters out at least reference signal quality for meeting preset condition from all reference signal qualities, from described The highest base station of a synchronization level is selected as Reference BTS eat dishes without rice or wine together in the corresponding base station of an at least reference signal quality Step, the synchronization level for adjusting this base station is a grade lower than the synchronization level of the Reference BTS.

Optionally, if this base station can get the synchronizing signal of at least one base station, base in continuous N synchronizing cycle Synchronizing signal at least one base station got, determines the corresponding reference signal quality at least one base station, obtains all Reference signal quality, at least reference signal quality for meeting preset condition is filtered out from all reference signal qualities, When selecting the highest base station of a synchronization level to carry out air interface synchronization from the corresponding base station of an at least reference signal quality, institute Synchronization unit is stated to be specifically used for：

If this base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, based on acquisition The synchronizing signal at least one base station arrived, determines the corresponding reference signal quality at least one base station, obtains all references Signal quality, the reference signal quality that isolated island base station is filtered out from all reference signal qualities obtain remaining reference signal Quality, filters out at least reference signal matter that reference signal quality is more than predetermined threshold value from remaining reference signal quality Amount, selected from the corresponding base station of an at least reference signal quality the highest base station of a synchronization level as Reference BTS into Row air interface synchronization.

Brief description of the drawings

Fig. 1 is the air interface synchronization method flow diagram based on networking in inventive embodiments；

Fig. 2 is the synchronous network schematic diagram of base station in the embodiment of the present invention；

Fig. 3 is the frame format schematic diagram of LTE TDD systems；

Fig. 4 is the air interface synchronization apparatus structure schematic diagram based on networking in inventive embodiments.

Embodiment

Below in conjunction with the attached drawing in the embodiment of the present invention, the technical solution in the embodiment of the present invention is carried out clear, complete Site preparation describes, it is clear that described embodiment is only part of the embodiment of the present invention, is not whole embodiments.It is based on Embodiment in the present invention, those of ordinary skill in the art are obtained every other without making creative work Embodiment, belongs to the scope of protection of the invention.

A kind of air interface synchronization method based on networking is provided in the embodiment of the present invention.For under network environment, between base station The synchronous accuracy for interfering with each other problem, influencing FemtoCell, the method that multi-hop synchronization is used in the embodiment of the present invention, respectively A base station issues synchronizing signal and synchronization level information at the agreement moment in advance, completes the renewal of synchronization level, keeps synchronous State, further improves the precision of base station synchronization, improves the throughput of more base station networkings.

As shown in fig.1, providing a kind of air interface synchronization method based on networking in the embodiment of the present invention, idiographic flow is such as Under：

In the pre-configured stage, any one base station of networking carries out global positioning system (Global Positioning successively System, GPS) synchronization, 1588 synchronizations and air interface synchronization；If a base station is synchronous by GPS or 1588 mode completion timings, The synchronization level of one base station is secondary high-grade.Wherein, the synchronization level of macro base station is highest ranking；If a base station passes through sky Mouth method of synchronization completion timing is synchronous, then according to the synchronization level of the Reference BTS of a base station, determines the synchronization of a base station Grade, wherein, the synchronization level of macro base station is highest ranking, if the Reference BTS is macro base station, synchronization of a base station etc. Level is secondary high-grade, if the Reference BTS is non-macro base station, the synchronization level of a base station is than synchronization of the Reference BTS etc. The low grade of level；If a base station can not complete synchronization, it is determined that a base station is isolated island base station, the synchronization of the isolated island base station Grade is the lowest class." 1588 " in the application refer to IEEE1588, and 1588 is synchronous i.e. according to network measure and control system The base station synchronization that the precision interval clock synchronous protocol standard of system carries out.

For example, the base station in networking is after the power is turned on, GPS is carried out successively, 1588, air interface synchronization.If certain base station A is with GPS, 1588 Synchronous, then A synchronization levels in base station are 0；It is synchronous etc. according to other side's hierarchical selection itself if certain base station B and other base station synchronizations Level, if synchronous base station is macro base station, the synchronization level of base station B is 0；If synchronous base station grade is 0, base station B's is same It is 1 to walk grade；The non-isolated island base station of prioritizing selection synchronizes, wherein the synchronization level that can set macro base station is highest ranking Represented with -1, synchronization level 0 is secondary high-grade, and the number of synchronization level is flexibly set according to network environment.

Step 100：When reaching each synchronizing cycle, the base station in networking is determined according to the synchronization level of itself Offset synchronization time of itself.

Specifically, the base station in networking utilizes the synchronization level of systemic presupposition and the mapping relations of offset synchronization time According to the synchronization level of itself, offset synchronization time of itself is determined.

For example, it is T to set synchronizing cycle, T can be the arbitrarily long time, and unit is radio frames, and length is times of radio frames Number.For Long Term Evolution (Long Term Evolution, LTE) system, wireless frame length is 10ms, radio frame number (System Frame Number, SFN) the setting offset synchronization time T_offset of scope 0~1023., according to the difference of synchronization level, set Different T_offset, unit are radio frames.For example, as shown in fig.2, it is 1024 SFN, i.e. T=to set T 10240ms, the macro base station in networking need not intercept other base stations, and synchronization level is 0 base station, it is only necessary to macro base station is intercepted, T_offset=1, then every 1024 SFN, synchronization intercept in the radio frames of SFN=0, and synchronization level is 1 base station, T_ Offset=2, every 1024 SFN, synchronization intercept in the radio frames of SFN=1, and synchronization level is 2 base station, T_ Offset=3, every 1024 SFN, carries out intercepting synchronization in the radio frames of SFN=2, and so on.A base station in networking According to the synchronization level of itself, offset synchronization time of itself is determined.

Step 101：According to offset synchronization time of itself, determine itself intercepts subframe and same step for an above-mentioned base station Frame.

Specifically, synchronization time offset of the base station according to itself, determine itself intercepts subframe and synchronous subframe, tool Body process is：One base station using systemic presupposition synchronization time offset and intercept the mapping relations of radio frames according to itself Synchronization time offset, determine itself intercepts radio frames, and the subframe 1 for intercepting radio frames of itself is arranged to the synchronization of itself Subframe, wherein, which dispatches in the synchronous subframe of itself without data service, non-isolated island base station in synchronous subframe Three symbols send the auxiliary synchronous signals (Secondary Synchronized Signal, SSS) of subframe 0 and skip main synchronization The resource block (Resource Block, RB) that signal (Primary Synchronized Signal, PSS) takes, isolated island base station The SSS of subframe 5 is sent in the 3rd symbol of synchronous subframe and skips the RB of PSS occupancy；The base station will be than itself synchronization level What the synchronous subframe of high target BS was arranged to itself intercepts subframe.

For example, determine T synchronizing cycle, and after the simultaneous bias T_offset intercepted, intercept wireless where the moment Frame determines that.The subframe intercepted further is selected, subframe is intercepted and is arranged to subframe 1, according to the frame format of LTE system, for TDD system, frame format is as shown in fig.3, subframe 1 is special subframe.The time slot proportion of specific LTE TDD systems, see Shown in table 1.

Table 1

Specifically, for being listened subframe, such as the base station that synchronization level is 1 can intercept synchronization in the subframe 1 of SFN=1 Grade is 0 base station.At this time, it is to be listened subframe for the base station that synchronization level is 0, the subframe 1 of the radio frames of SFN=1, And the synchronous subframe of the base station.First, in the subframe, dispatch without data service (Downlink Share Channel, DL_SCH), control signal is only sent；SSS is sent in the 3rd symbol, that is, symbol 2 of the subframe 1, according to the PSS of the base station SSS, is mapped to different positions by difference, avoids disturbing.PSS has (0,1,2) three roots, that is, has three kinds of situations.Since PSS consolidates Determine 6 RB among occupied bandwidth, SSS is also required to take 6 RB.For system more than 5MHz bandwidth, RB numbers are more than etc. In 25, according to PSS root sequence values { 0,1,2 }, mapped in sequence successively, if root sequence is 0 since the 0th RB SSS is mapped, if root sequence is 1, is mapped since the 6th RB.The RB of PSS occupancy is skipped in mapping process；Due to LTE groups Net can be maximized using this mapping method and avoid SSS signal interferences between adjacent base station using 3 networking mode of mould, and right In the system that bandwidth is 3MHz, then SSS is all mapped since the 0th RB, while skip the RB of PSS occupancy.Here mapping Mode is not unique, as long as the RB that SSS takes can be made not conflict with the PSS resource block RB taken, passes through synchronous subframe SSS positions and the mapping of PSS root sequences, can substantially reduce adjacent base station SSS signal interferences.

Step 102：An above-mentioned base station is by the synchronizing signal intercepted subframe and obtain target BS of itself, based on the synchronization Signal determines the Reference BTS of a base station, and the synchronizing signal based on the Reference BTS and the benchmark base from the target BS Air interface synchronization is established at station, and the wherein synchronizing signal is sent for the target BS by the synchronous subframe of itself, the target BS For the base station higher than the synchronization level of a base station.

Specifically, a base station in intercepting for itself by not sending downlink signal and obtaining the synchronization of target BS in subframe Signal, the synchronizing signal of the target BS include master sync signal and auxiliary synchronous signals, and the synchronizing signal of the target BS is mesh Mark what base station was sent by the synchronous subframe of itself.

For example, for intercepting subframe, special subframe 1 is switched to sub-frame of uplink, is intercepted by the base station of low synchronization level. For different synchronization levels, it is different and different according to T_offset to intercept subframe, in order to avoid different synchronization level bases The interference stood, it is normally opened that synchronous subframe of the low synchronization level base station in high-grade base station is all switched to uplink, for example, can join Read shown in Fig. 2, the base station that synchronization level is 3 does not send downlink signal in grade for the synchronous subframe of -1,0,1 and 2 base stations, is changed to Uplink is normally opened.The subframe includes PSS and SSS at the same time, therefore can be by PSS, and SSS obtains cell ID (Cell_ID), while root Cell reference signals (cell reference signal, Cell_RS) are demodulated according to Cell_ID, obtain the matter of cell reference signals Measure (Reference Signal Receiving Quality, RSRQ).

In this way, be listened base station sends SSS by the symbol where PSS, it can make to intercept base station by intercepting single son Frame obtains the Cell_ID for being listened station, and then obtains reference signal RSRQ by parsing cell reference signals, synchronizes Level judgement, avoids the influence for intercepting multiple subframes to regular traffic.High synchronization level base station is sent in the synchronous subframe of itself SSS, while DL_SCH is not dispatched, only send control signal；Low synchronization level base station is in the corresponding synchronization in high synchronization level base station Subframe synchronizes, adjust frequency deviation and when it is inclined.Such as Fig. 2, base station C intercepts subframe at second and intercepts base station B, with upper level base station B is synchronized, while base station C intercepts subframe at first and intercepts base station A (macro base station).

Specifically, the synchronizing signal intercepting subframe obtain target BS of the base station by itself, based on the synchronizing signal The Reference BTS of the base station is determined from the target BS, and the synchronizing signal based on the Reference BTS is established with the Reference BTS Air interface synchronization, detailed process are：The base station is by the synchronizing signal intercepted subframe and obtain target BS of itself, based on acquisition Synchronizing signal, determines the corresponding reference signal quality of target BS, obtains the reference signal quality of all target BS；The base station The reference signal quality based on all target BS, selects a target BS as a base station from all target BS Reference BTS；The base station obtains the synchronizing signal of Reference BTS, and air interface synchronization is established based on the synchronizing signal and Reference BTS.

Specifically, reference signal quality of the base station based on all target BS, selects a mesh from all target BS Reference BTS of the base station as the base station is marked, detailed process is：If a base station detects a target in continuous N synchronizing cycle The reference signal quality of base station be more than the synchronization level of default threshold value and the target BS than the base station synchronization level at least During high two grades, the Reference BTS using the target BS as the base station；Otherwise, the ratio of selection one should from all target BS The target BS of the high grade of synchronization level of base station is as Reference BTS.

Further, a base station obtains the synchronizing signal of Reference BTS, is established based on the synchronizing signal and the Reference BTS After air interface synchronization, which obtains the synchronization level of the Reference BTS, if the synchronization level of the Reference BTS is than a base During the high grade of the synchronization level stood, then keep the synchronization level of a base station constant；If the synchronization level of the Reference BTS Than a base station synchronization level at least tall person's two-stage when, then the synchronization level of a base station is adjusted to than the Reference BTS The low level-one of synchronization level.

For example, when reaching each synchronizing cycle, it is a certain intercept base station E except with upper level base station (Reference BTS) into Row is synchronous, while the synchronous subframe in higher synchronization level base station is intercepted, and according to PSS, SSS determines Cell_ID, Jin Ergen According to the Cell_RS in first symbol of synchronous subframe, RSRQ_H is calculated, judges whether to need to improve synchronization level, setting is sentenced Disconnected thresholding is H, if continuous N (M is the positive integer of setting) all detects a certain synchronization level base station F's in a synchronizing cycle RSRQ_H>H, and at least high two-stage of synchronization level of the synchronization level than base station E of base station F, at this time, base station E using base station F as Reference BTS, base station E and base station F carries out air interface synchronization, and improves the synchronization level of base station E, and the synchronization level of base station E is changed For a grade lower than the synchronization level of base station F.

Further, a base station obtains the synchronizing signal of the Reference BTS, is built based on the synchronizing signal and the Reference BTS After vertical air interface synchronization, if a base station cannot detect the Reference BTS of a base station in continuous N synchronizing cycle, When next synchronizing cycle reaches, synchronous subframe of the base station in the base station of each synchronization level intercepts synchronizing signal, and judgement is The no synchronizing signal that at least one base station can be got in continuous N synchronizing cycle, including two kinds of situations：

The first situation is：The base station can not get the synchronous letter of at least one base station in continuous N synchronizing cycle Number, then the base station sends the auxiliary synchronous signals of subframe 5 in the synchronous subframe of itself, determines that itself is isolated island base station, adjusts itself Synchronization level be the lowest class.

Second case is：The base station can get the synchronous letter of at least one base station in continuous N synchronizing cycle Number, based on the synchronizing signal of at least one base station got, determine the corresponding reference signal quality at least one base station, obtain All reference signal qualities, filter out at least reference signal matter for meeting preset condition from all reference signal qualities Amount, selects the highest base station of a synchronization level to be carried out as Reference BTS from the corresponding base station of an at least reference signal quality Air interface synchronization, it is a grade lower than the synchronization level of the Reference BTS to adjust the synchronization level of itself.

If specifically, a base station can get the synchronizing signal of at least one base station, base in continuous N synchronizing cycle Synchronizing signal at least one base station got, determines the corresponding reference signal quality at least one base station, obtains all Reference signal quality, at least reference signal quality for meeting preset condition is filtered out from all reference signal qualities, The highest base station of a synchronization level is selected to carry out air interface synchronization, specific mistake from the corresponding base station of an at least reference signal quality Cheng Wei：If the base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, based on what is got The synchronizing signal of at least one base station, determines the corresponding reference signal quality at least one base station, obtains all reference signals Quality, the reference signal quality that isolated island base station is filtered out from all reference signal qualities obtain remaining reference signal matter Amount, filters out at least reference signal quality that reference signal quality is more than predetermined threshold value from remaining reference signal quality, The highest base station of a synchronization level is selected to be carried out as Reference BTS from the corresponding base station of an at least reference signal quality empty Mouth is synchronous.

For example, a certain base station D has found that oneself synchronous Reference BTS lost, i.e. base station D is in continuous N synchronizing cycle It can not detect the Reference BTS of the base station, then base station D attempts to be intercepted in the synchronous subframe of each synchronization level, if even Continue M times and listen to less than other base stations, then it is isolated island base station to state this base station, and subframe is sent in the 3rd symbol of synchronous subframe 5 SSS signals, if continuous N time can listen to other base stations, from the base station that can be listened to, exclude first Isolated island base station, secondly each base station signal quality meet to a certain degree in the case of, the high base station of prioritizing selection synchronization level Synchronize, so as to ensure the reliability of synchronous clock source.

Based on above-mentioned technical proposal, as shown in fig.4, providing a kind of air interface synchronization based on networking in the embodiment of the present invention Device, positioned at base station side, including：First determination unit 40, the second determination unit 41 and synchronization unit 42, wherein：

First determination unit 40, for when reaching each synchronizing cycle, according to the synchronization level of this base station, determining this Offset synchronization time of base station；

Second determination unit 41, for offset synchronization time according to this base station, determine this base station intercept subframe and Synchronous subframe；

Synchronization unit 42, for the synchronizing signal intercepted subframe and obtain target BS by this base station, based on the synchronization Signal determines the Reference BTS of this base station, and the synchronizing signal based on the Reference BTS and the Reference BTS from the target BS Air interface synchronization is established, the wherein synchronizing signal is sent for the target BS by the synchronous subframe of itself, which is The base station higher than the synchronization level of this base station.

Optionally, synchronization unit 42 is further used for：

If this base station is synchronous by air interface synchronization mode completion timing, according to synchronization of the Reference BTS of this base station etc. Level, determines the synchronization level of this base station, wherein, the synchronization level of macro base station is highest ranking, if the Reference BTS is macro base station, Then the synchronization level of this base station is secondary high-grade, if the Reference BTS is non-macro base station, the synchronization level of this base station is than the base The low grade of synchronization level of quasi- base station；

If this base station can not complete synchronization, it is determined that this base station is isolated island base station, and the synchronization level of the isolated island base station is most Inferior grade.

Optionally, according to the synchronization level of this base station, when determining offset synchronization time of this base station, the first determination unit 40 are specifically used for：

Optionally, according to offset synchronization time of this base station, when intercepting subframe and synchronous subframe of this base station is determined, the Two determination units 41 are specifically used for：

When optionally, by the synchronizing signal for intercepting subframe acquisition target BS of this base station, synchronization unit 42 is specifically used In：

By not sending downlink signal in subframe in intercepting for this base station and obtaining the synchronizing signal of target BS, the target The synchronizing signal of base station includes master sync signal PSS and auxiliary synchronous signals SSS, and the synchronizing signal of the target BS is target BS Sent by the synchronous subframe of itself.

Optionally, by this base station intercept subframe obtain target BS synchronizing signal, based on the synchronizing signal from this The Reference BTS of this base station is determined in target BS, and is established and eated dishes without rice or wine with the Reference BTS based on the synchronizing signal of the Reference BTS When synchronous, synchronization unit 42 is specifically used for：

The synchronizing signal of the Reference BTS is obtained, air interface synchronization is established based on the synchronizing signal and the Reference BTS.

Optionally, the reference signal quality based on all target BS, selects a target BS from all target BS During Reference BTS as this base station, synchronization unit 42 is specifically used for：

If this base station continuous N detects that the reference signal quality of a target BS is more than default threshold value in synchronizing cycle And the synchronization level of this base station of the synchronization level of a target BS at least high two grades when, using a target BS be used as this The Reference BTS of base station；Otherwise, the target of a grade higher than the synchronization level of this base station is selected from all target BS Base station is as Reference BTS.

Optionally, the synchronizing signal of the Reference BTS is obtained, is established and is eated dishes without rice or wine together based on the synchronizing signal and the Reference BTS After step, synchronization unit 42 is further used for：

The synchronization level of the Reference BTS is obtained, if the synchronization level of the Reference BTS is higher than the synchronization level of this base station by one During a grade, then keep the synchronization level of this base station constant；If the synchronization level of the Reference BTS is than the synchronization level of this base station At least tall person's two-stage when, then the synchronization level of this base station is adjusted to level-one lower than the synchronization level of the Reference BTS.

If this base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, based on acquisition The synchronizing signal at least one base station arrived, determines the corresponding reference signal quality at least one base station, obtains all references Signal quality, filters out at least reference signal quality for meeting preset condition from all reference signal qualities, from this to The highest base station of a synchronization level is selected to carry out air interface synchronization as Reference BTS in few corresponding base station of a reference signal quality, The synchronization level for adjusting this base station is a grade lower than the synchronization level of the Reference BTS.

Optionally, if this base station can get the synchronizing signal of at least one base station, base in continuous N synchronizing cycle Synchronizing signal at least one base station got, determines the corresponding reference signal quality at least one base station, obtains all Reference signal quality, at least reference signal quality for meeting preset condition is filtered out from all reference signal qualities, It is synchronous when selecting the highest base station of a synchronization level to carry out air interface synchronization from the corresponding base station of an at least reference signal quality Unit 42 is specifically used for：

If this base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, based on acquisition The synchronizing signal at least one base station arrived, determines the corresponding reference signal quality at least one base station, obtains all references Signal quality, the reference signal quality that isolated island base station is filtered out from all reference signal qualities obtain remaining reference signal Quality, filters out at least reference signal matter that reference signal quality is more than predetermined threshold value from remaining reference signal quality Amount, selects the highest base station of a synchronization level to be carried out as Reference BTS from the corresponding base station of an at least reference signal quality Air interface synchronization.

In conclusion in the embodiment of the present invention, when reaching each synchronizing cycle, the base station in networking is according to itself Synchronization level, determine offset synchronization time of itself；The base station determines itself according to offset synchronization time of itself Intercept subframe and synchronous subframe；The base station is by the synchronizing signal intercepted subframe and obtain target BS of itself, based on the synchronization Signal determines the Reference BTS of the base station from target BS, and is built based on the synchronizing signal of the Reference BTS and the Reference BTS Vertical air interface synchronization, in such manner, it is possible to make whole network complete automatic network-building, and searches for the letter of high synchronization level automatically in networking Source, changes the synchronization level of base station in real time, i.e., the clock grade of a certain base station changes during networking, also can again certainly Adapt to this change, it is not necessary to interrupt regular traffic and be adapted to the synchronization level of oneself with regard to that can find each base station, complete whole The synchronization of network, the synchronization level for being optimal each base station, avoiding respective base stations from exception occur causes whole network step-out, So as to improve the synchronous self-healing ability of whole network.

It should be understood by those skilled in the art that, the embodiment of the present invention can be provided as method, system or computer program Product.Therefore, the present invention can use the reality in terms of complete hardware embodiment, complete software embodiment or combination software and hardware Apply the form of example.Moreover, the present invention can use the computer for wherein including computer usable program code in one or more The computer program production that usable storage medium is implemented on (including but not limited to magnetic disk storage, CD-ROM, optical memory etc.) The form of product.

The present invention be with reference to according to the method for the embodiment of the present invention, the flow of equipment (system) and computer program product Figure and/or block diagram describe.It should be understood that it can be realized by computer program instructions every first-class in flowchart and/or the block diagram The combination of flow and/or square frame in journey and/or square frame and flowchart and/or the block diagram.These computer programs can be provided The processors of all-purpose computer, special purpose computer, Embedded Processor or other programmable data processing devices is instructed to produce A raw machine so that the instruction performed by computer or the processor of other programmable data processing devices, which produces, to be used in fact The device for the function of being specified in present one flow of flow chart or one square frame of multiple flows and/or block diagram or multiple square frames.

These computer program instructions, which may also be stored in, can guide computer or other programmable data processing devices with spy Determine in the computer-readable memory that mode works so that the instruction being stored in the computer-readable memory, which produces, to be included referring to Make the manufacture of device, the command device realize in one flow of flow chart or multiple flows and/or one square frame of block diagram or The function of being specified in multiple square frames.

These computer program instructions can be also loaded into computer or other programmable data processing devices so that counted Series of operation steps is performed on calculation machine or other programmable devices to produce computer implemented processing, thus in computer or The instruction performed on other programmable devices is provided and is used for realization in one flow of flow chart or multiple flows and/or block diagram one The step of function of being specified in a square frame or multiple square frames.

Although preferred embodiments of the present invention have been described, but those skilled in the art once know basic creation Property concept, then can make these embodiments other change and modification.So appended claims be intended to be construed to include it is excellent Select embodiment and fall into all change and modification of the scope of the invention.

Obviously, those skilled in the art can carry out the embodiment of the present invention various modification and variations without departing from this hair The spirit and scope of bright embodiment.In this way, if these modifications and variations of the embodiment of the present invention belong to the claims in the present invention And its within the scope of equivalent technologies, then the present invention is also intended to comprising including these modification and variations.

Claims

A kind of 1. air interface synchronization method based on networking, it is characterised in that including：

When reaching each synchronizing cycle, a base station in networking is according to the synchronization level of itself, when determining the synchronization of itself Between offset；

According to offset synchronization time of itself, determine itself intercepts subframe and synchronous subframe for one base station；

One base station is by the synchronizing signal intercepted subframe and obtain target BS of itself, the synchronizing signal based on acquisition, really Set the goal the corresponding reference signal quality in base station, obtains the reference signal quality of all target BS, if base station continuous N Detect that the reference signal quality of a target BS is more than the same of default threshold value and a target BS in a synchronizing cycle Walk grade than a base station synchronization level at least high two grades when, using a target BS as a base station Reference BTS, otherwise, selects the target base of a grade higher than the synchronization level of a base station from all target BS Stand and be used as Reference BTS, a base station obtains the synchronizing signal of the Reference BTS, based on the synchronizing signal and the base Air interface synchronization is established in quasi- base station, wherein what the synchronizing signal was sent for the target BS by the synchronous subframe of itself, institute It is the base station higher than the synchronization level of a base station to state target BS.
2. the method as described in claim 1, it is characterised in that further comprise：

In the pre-configured stage, a base station carries out synchronous global position system GPS, 1588 synchronizations of IEEE and eats dishes without rice or wine same successively Step；

If a base station is synchronous by GPS or 1588 mode completion timings of IEEE, the synchronization level of a base station is secondary It is high-grade；Wherein, the synchronization level of macro base station is highest ranking；

If a base station is synchronous by air interface synchronization mode completion timing, according to the synchronization of the Reference BTS of a base station Grade, determines the synchronization level of a base station, wherein, the synchronization level of macro base station is highest ranking, if the Reference BTS For macro base station, then the synchronization level of a base station is secondary high-grade, if the Reference BTS is non-macro base station, a base The synchronization level a stood grade lower than the synchronization level of the Reference BTS；

If a base station can not complete synchronization, it is determined that a base station is isolated island base station, the synchronization of the isolated island base station etc. Level is the lowest class.
3. the method as described in claim 1 a, it is characterised in that base station determines itself according to the synchronization level of itself Offset synchronization time, including：

One base station is using the synchronization level of systemic presupposition with the mapping relations of offset synchronization time according to the synchronous of itself Grade, determines offset synchronization time of itself.
4. the method as described in claim 1 a, it is characterised in that base station is according to offset synchronization time of itself, really It is fixed itself to intercept subframe and synchronous subframe, including：

One base station using systemic presupposition synchronization time offset with intercepting the mapping relations of radio frames according to the same of itself Time offset is walked, determine itself intercepts radio frames, and the subframe 1 for intercepting radio frames of itself is arranged to the same step of itself Frame, wherein, a base station is dispatched in the synchronous subframe of itself without data service, non-isolated island base station in synchronous subframe Three symbols send the auxiliary synchronous signals SSS of subframe 0 and skip the resource block RB of master sync signal PSS occupancy, and isolated island base station exists 3rd symbol of synchronous subframe sends the auxiliary synchronous signals SSS of son 5 and skips the resource block RB of master sync signal PSS occupancy；

Subframe is intercepted by what the synchronous subframe of the target BS higher than itself synchronization level was arranged to itself in one base station.
5. the method as described in claim 1 a, it is characterised in that base station obtains target base by the subframe of intercepting of itself The synchronizing signal stood, including：

One base station in intercepting for itself by not sending downlink signal and obtaining the synchronizing signal of target BS, institute in subframe State the synchronizing signal of target BS and include master sync signal PSS and auxiliary synchronous signals SSS, the synchronizing signal of the target BS and be Target BS is sent by the synchronous subframe of itself.
6. the method as described in claim 1, it is characterised in that a base station obtains the synchronizing signal of the Reference BTS, After establishing air interface synchronization based on the synchronizing signal and the Reference BTS, further comprise：

One base station obtains the synchronization level of the Reference BTS, if the synchronization level of the Reference BTS is than a base station A synchronization level high grade when, then keep the synchronization level of a base station constant；If synchronization of the Reference BTS etc. Level than a base station synchronization level at least tall person's two-stage when, then the synchronization level of a base station is adjusted to than the base The low level-one of synchronization level of quasi- base station.
7. the method as described in claim 1, it is characterised in that a base station obtains the synchronizing signal of the Reference BTS, After establishing air interface synchronization based on the synchronizing signal and the Reference BTS, further comprise：

If a base station cannot detect the Reference BTS of a base station in continuous N synchronizing cycle, next When synchronizing cycle reaches, synchronous subframe of the base station in the base station of each synchronization level intercepts synchronizing signal, judges whether The synchronizing signal of at least one base station can be got in continuous N synchronizing cycle；

If a base station can not get the synchronizing signal of at least one base station in continuous N synchronizing cycle, described one Base station sends the auxiliary synchronous signals of subframe 5 in the synchronous subframe of itself, determines that itself is isolated island base station, adjusts synchronization of itself etc. Level is the lowest class；

If a base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, based on acquisition The synchronizing signal at least one base station arrived, determines the corresponding reference signal quality at least one base station, obtains all references Signal quality, filters out at least reference signal quality for meeting preset condition from all reference signal qualities, from described The highest base station of a synchronization level is selected as Reference BTS eat dishes without rice or wine together in the corresponding base station of an at least reference signal quality Step, it is a grade lower than the synchronization level of the Reference BTS to adjust the synchronization level of itself.
8. the method for claim 7, it is characterised in that if a base station can be obtained in continuous N synchronizing cycle The synchronizing signal of at least one base station is got, based on the synchronizing signal of at least one base station got, determines at least one base Stand corresponding reference signal quality, obtain all reference signal qualities, filter out and meet from all reference signal qualities An at least reference signal quality for preset condition, selects synchronization etc. from the corresponding base station of an at least reference signal quality The highest base station of level carries out air interface synchronization, including：

If a base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, based on acquisition The synchronizing signal at least one base station arrived, determines the corresponding reference signal quality at least one base station, obtains all references Signal quality, the reference signal quality that isolated island base station is filtered out from all reference signal qualities obtain remaining reference signal Quality, filters out at least reference signal matter that reference signal quality is more than predetermined threshold value from remaining reference signal quality Amount, selected from the corresponding base station of an at least reference signal quality the highest base station of a synchronization level as Reference BTS into Row air interface synchronization.
A kind of 9. air interface synchronization device based on networking, positioned at base station side, it is characterised in that including：

First determination unit, for when reaching each synchronizing cycle, according to the synchronization level of this base station, determining this base station Synchronization time offset；

Second determination unit, for offset synchronization time according to this base station, determine this base station intercepts subframe and same step Frame；

Synchronization unit, for the synchronizing signal intercepted subframe and obtain target BS by this base station, the synchronization letter based on acquisition Number, determine the corresponding reference signal quality of target BS, obtain the reference signal quality of all target BS, if this base station is continuous Detect that the reference signal quality of a target BS is more than the same of default threshold value and a target BS in M synchronizing cycle Walk the synchronization level of grade this base station at least high two grades when, the Reference BTS using a target BS as this base station, Otherwise, the target BS of a grade higher than the synchronization level of this base station is selected from all target BS as benchmark base Stand, obtain the synchronizing signal of the Reference BTS, air interface synchronization is established based on the synchronizing signal and the Reference BTS, wherein The synchronizing signal is sent for the target BS by the synchronous subframe of itself, and the target BS is more same than this base station Walk the high base station of grade.
10. device as claimed in claim 9, it is characterised in that the synchronization unit is further used for：

In the pre-configured stage, synchronous global position system GPS, 1588 synchronizations of IEEE and air interface synchronization are carried out successively；

If this base station is synchronous by GPS or 1588 mode completion timings of IEEE, it is determined that the synchronization level of this base station is secondary high Level；Wherein, the synchronization level of macro base station is highest ranking；

If this base station is synchronous by air interface synchronization mode completion timing, according to the synchronization level of the Reference BTS of this base station, really The synchronization level of this fixed base station, wherein, the synchronization level of macro base station is highest ranking, if the Reference BTS is macro base station, The synchronization level of this base station is secondary high-grade, if the Reference BTS is non-macro base station, described in the synchronization level ratio of this base station The low grade of synchronization level of Reference BTS；

If this base station can not complete synchronization, it is determined that this base station is isolated island base station, and the synchronization level of the isolated island base station is minimum Grade.
11. device as claimed in claim 9, it is characterised in that according to the synchronization level of this base station, determine the synchronization of this base station During time offset, first determination unit is specifically used for：

Synchronization level using the synchronization level of systemic presupposition with the mapping relations of offset synchronization time according to this base station, determines Offset synchronization time of this base station.
12. device as claimed in claim 9, it is characterised in that according to offset synchronization time of this base station, determine this base station When intercepting subframe and synchronous subframe, second determination unit is specifically used for：

Using systemic presupposition synchronization time offset and the mapping relations of intercepting radio frames it is inclined according to the synchronization time of this base station Shifting amount, determine this base station intercepts radio frames, and the subframe 1 for intercepting radio frames of this base station is arranged to the same step of this base station Frame, wherein, any one base station is dispatched in the synchronous subframe of itself without data service, non-isolated island base station in synchronous subframe Three symbols send the auxiliary synchronous signals SSS of subframe 0 and skip the resource block RB of master sync signal PSS occupancy, and isolated island base station exists 3rd symbol of synchronous subframe sends the auxiliary synchronous signals SSS of son 5 and skips the resource block RB of master sync signal PSS occupancy；

Subframe is intercepted by what the synchronous subframe of target BS than this base station synchronization higher grade was arranged to this base station.
13. device as claimed in claim 9, it is characterised in that the same of target BS is obtained by the subframe of intercepting of this base station When walking signal, the synchronization unit is specifically used for：

By downlink signal not sent in subframe obtaining the synchronizing signal of target BS, the target base in intercepting for this base station The synchronizing signal stood includes master sync signal PSS and auxiliary synchronous signals SSS, and the synchronizing signal of the target BS is target BS Sent by the synchronous subframe of itself.
14. device as claimed in claim 9, it is characterised in that the synchronizing signal of the Reference BTS is obtained, based on described same Step signal is established after air interface synchronization with the Reference BTS, and the synchronization unit is further used for：

The synchronization level of the Reference BTS is obtained, if the synchronization level of the Reference BTS is higher than the synchronization level of this base station by one During a grade, then keep the synchronization level of this base station constant；If the synchronization level of the Reference BTS is than synchronization of this base station etc. Level at least tall person's two-stage when, then the synchronization level of this base station is adjusted to level-one lower than the synchronization level of the Reference BTS.
15. device as claimed in claim 9, it is characterised in that the synchronizing signal of the Reference BTS is obtained, based on described same Step signal is established after air interface synchronization with the Reference BTS, and the synchronization unit is further used for：

If this base station cannot detect the Reference BTS of this base station in continuous N synchronizing cycle, in next synchronizing cycle During arrival, the synchronous subframe in the base station of each synchronization level intercepts synchronizing signal, and judging whether can be in continuous N synchronous week The interim synchronizing signal for getting at least one base station；

If this base station can not get the synchronizing signal of at least one base station in continuous N synchronizing cycle, in this base station Synchronous subframe sends the auxiliary synchronous signals of subframe 5, and it is isolated island base station to determine this base station, and the synchronization level for adjusting this base station is minimum Grade；

If this base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, based on what is got The synchronizing signal of at least one base station, determines the corresponding reference signal quality at least one base station, obtains all reference signals Quality, filters out at least reference signal quality for meeting preset condition from all reference signal qualities, from it is described at least Select the highest base station of a synchronization level to carry out air interface synchronization as Reference BTS in the corresponding base station of one reference signal quality, adjust The synchronization level of this whole base station is a grade lower than the synchronization level of the Reference BTS.
16. device as claimed in claim 15, it is characterised in that if this base station can obtain in continuous N synchronizing cycle To the synchronizing signal of at least one base station, based on the synchronizing signal of at least one base station got, at least one base station is determined Corresponding reference signal quality, obtains all reference signal qualities, filtered out from all reference signal qualities meet it is pre- If an at least reference signal quality for condition, a synchronization level is selected from the corresponding base station of an at least reference signal quality When highest base station carries out air interface synchronization, the synchronization unit is specifically used for：

If this base station can get the synchronizing signal of at least one base station in continuous N synchronizing cycle, based on what is got The synchronizing signal of at least one base station, determines the corresponding reference signal quality at least one base station, obtains all reference signals Quality, the reference signal quality that isolated island base station is filtered out from all reference signal qualities obtain remaining reference signal matter Amount, filters out at least reference signal quality that reference signal quality is more than predetermined threshold value from remaining reference signal quality, The highest base station of a synchronization level is selected to be carried out as Reference BTS from the corresponding base station of an at least reference signal quality Air interface synchronization.