CN102905274B

CN102905274B - Frequency allocating method based on hierarchical wireless access system

Info

Publication number: CN102905274B
Application number: CN201210377426.XA
Authority: CN
Inventors: 张诗壮
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2008-07-03
Filing date: 2008-07-03
Publication date: 2015-04-29
Anticipated expiration: 2028-07-03
Also published as: CN102905274A

Abstract

The invention discloses a frequency allocating method based on a hierarchical wireless access system. The hierarchical wireless access system comprises access point managing units which are positioned in an access layer and access points which are hanged in the access point managing units, after being started and working normally, the access points apply for frequency point resources from the access point managing unit to which the access points belong; the access point managing units determine a candidate frequency point of each access point according to an adjacent relation between the access points and transmit the candidate frequency point to a corresponding access point; and after receiving own candidate frequency point, the access point detects the signal quality of the candidate frequency point, and enters a normal working flow after the signal quality of the candidate frequency point passes the detection. By the frequency allocating method, network environments with different complexity levels can be adapted by enabling or disabling a network management interface.

Description

The frequency allocation method of layered radio access system

The application is the divisional application of No. 200880129784.0 application, and the applying date of original application is on 07 03rd, 2008, and application number is 200880129784.0, and name is called " synchronous, the scheduling of layered radio access system, network management and frequency allocation method ".

Technical field

The present invention relates to a kind of wireless access system, particularly relate to the access point administrative unit in a kind of system of layering wireless access, this system and the correlation technique based on this system.

Background technology

Existing WiMAX (Worldwide Interoperability for Microwave Access, micro-wave access to global intercommunication) mobile network architecture signal is as shown in Figure 1, this framework comprises terminal CPE (the Customer Premises Equipment of WiMAX, ustomer premises access equipment) 101, the BS (base station) 102 of WiMAX access network, ASN-GW (access service network gateway, also referred to as IAD in literary composition) 103, the CSN (connectivity serving network) 104 of WiMAX, and PDN (Packet Data Network, packet data network) or SDH (Synchronous Digital Hierarchy, SDH (Synchronous Digital Hierarchy)) 105.Wherein, CPE 101, BS 102 and ASN-GW 103 constitute the ASN (Access Service Network, access service network) of WiMAX.In being interconnected, it is the R1 interface of standard between CPE 101 and BS 102, it is the R6 interface of standard between BS 102 and ASN-GW 103, the R8 interface of standard is adopted between multiple BS 102, the Interface R4 of standard is adopted between multiple ASN-GW 103, adopt Interface R3 to interconnect between ASN-GW 103 and CSN 104, PDN/SDH 105 is the transmission bearer network of WiMAX.

Because the main flow frequency range that WiMAX system wireless frequency is current is 2.3/2.5/3.5GHz, if adopt the mode of traditional integrated form macro base station outdoor cover indoor, for dense city, penetration loss is larger, general according to 18 ~ 25dB budget, therefore take merely the mode of outdoor cover indoor, the minimizing of outdoor cover radius will be caused, the increase that outdoor station is counted, brings networking cost to increase and strengthens the difficulty of arranging net fast.In addition,, there is higher demand to capacity, need overlay area signal to noise ratio high in the focus concentrated for telephone traffic, enterprise and commercial building, the demand of high order modulation 16QAM or even 64QAM can be met, take the mode of traditional outdoor macro base station and micro-base station not meet the demands.

In addition,, there is higher demand to capacity, need overlay area signal to noise ratio high in the focus concentrated for telephone traffic, enterprise and commercial building, the demand of high order modulation 16QAM or even 64QAM can be met, take the mode of traditional outdoor macro base station and micro-base station not meet the demands.

Comprehensive, for WiMAX and follow-up 4G networking, for city and dense city, recommend to adopt Pico Cell (Pico cell) mode to carry out supplementing of in-door covering.The Pico Cell scheme of current existence comprises again the mode of baseband pool+Pico RRU and the Pico base station manner of integration; Emphasis of the present invention focuses on based on the improvement project based on integrated Pico BS (femto base station) and equipment control discussion.

Current mobile system adopts the usual method of disposing access point as follows:

Scheme 1: in overlay area, adopts the access point Pico BS of multiple separate configurations; Access point is connected with the IAD of central machine room by transmission network.Illustrate based on the in-door covering network of conventional P ico B/S framework.

As shown in Figure 2, between each area of coverage, (certain region of a floor as shown in the figure) disposes a Pico BS 201 to the network configuration of the program; Realize connecting by the switch of convergence or router two 02 between the access point Pico BS 201 of multiple separate configurations; Switch or router two 02 are provided to the R6 interface of transmission network PDN/SDH 203.Each Pico BS 201 needs to configure GPS module, to solve TDD (time division duplex) system synchronization problem, prevents the interference of system group network.Although the access point in a region is physically adjacent, but there is no logical channel communication each other, namely local access-in management unit is not had at whole building or building group yet, communication between Pico BS 201, comprise the switching control information between base station, and in region between access point the user plane information of user mutual, all have to pass through after PDN/SDH 203 routes to the ASN-GW 204 of central machine room node, be linked into CSN 205 again, be sent to target BS after treatment, this bandwidth for SDH/PDH network is a waste greatly.Simultaneously owing to needing the deterioration bringing the performance such as time delay and shake through public network route, user's impression is one and reduces greatly.In CBD (central business district) region of commercial building and big-and-middle capacity, the service switchover of most users occurs between floors, floor and the overlapping coverage areas such as escalator, aisle, and the demand switched has larger frequency, in traditional Pico B/S framework, Pico BS needs to support twisted-pair feeder, optical fiber or the interface such as coaxial, configuration gps antenna is needed to solve stationary problem, this brings larger difficulty to the deployment of indoor, be unfavorable for the optimization of network performance, and a lot of scene cannot solve or cost is very large.

In scheme 2: one overlay areas, adopt Pico/Micro/Pico BS to provide information source, by passive distributed system, distribute RF signal to multiple antenna element, the power of each antenna element is equivalent to the power of access point.Be the in-door covering network based on information source base station+distributed passive antenna system framework, be applicable to small-scale in-door covering network.

The network configuration of the program as shown in Figure 3, Signal Source BS (signal source base station) 301 may be Micro BS (microcell base station), also be likely Pico BS, concrete needs determine according to the scale of in-door covering and network topology situation.Information source base station provides RF (Radio frequency, radio frequency) signal to Power Divider (power splitter) 302 and Coupler (coupler) 303.By distributing layer by layer, output signal to ceiling mount antenna 304 and the wall aerial 305 of overlay area, the type selecting of concrete antenna is determined according to indoor landform and the network planning.The difference of power splitter 302 and coupler 303 is, power splitter 302 realizes power decile, and coupler 303 can realize the proportions of power to different port as requested.Adopt Pico/Micro/Pico BS to provide information source, by passive distributed system, distribute RF signal to multiple antenna element, the power of each antenna element is equivalent to the power of access point.The problem of this programme is exactly the power needing information source base station to provide larger, because the loss of passive distributed system is larger, so be not suitable for medium and large-scale indoor covering system networking, be exactly cell capacity-enlarging in addition, need larger engineering construction and deployment workload.

In scheme 3: one overlay areas, adopt Pico/Micro/Pico BS (indicating 501) to provide information source, by active distributed system, distribute RF signal to multiple antenna element, the power of each antenna element is equivalent to the power of access point.The in-door covering network based on information source base station+Distributed Active Antennas system architecture, large-scale in-door covering networking in being applicable to.

The network configuration of the program as shown in Figure 4, the connected mode of signal source base station 401, power splitter 402, coupler 403 and ceiling mount antenna 404 and wall aerial 405 and function, identical with the in-door covering network of the framework of passive antenna system shown in Fig. 3.Active distributed system shown in Fig. 4 and the maximum difference of passive distributed system are, in the intermediate trunk position that signal attenuation is larger, can dispose Trunk Amplifier (trunk amplifier) 404, the loss that opposing circuit transport tape comes.Because 802.16e is TDD system, require strict for time synchronized, trunk amplifier 404 can extract transmitting-receiving timing synchronization signal, compensates the symbol transmitting-receiving sequential that different circuit time delay is brought.Adopt Pico/Micro/Pico BS to provide information source, by active distributed system, distribute RF signal to multiple antenna element, the power of each antenna element is equivalent to the power of access point.This programme needs in the middle of transmission line, increase trunk amplifier 404 and carrys out compensated line loss, is suitable for the in-door covering network of big-and-middle scale.But shortcoming is the capacity extension being unfavorable for the later stage, be exactly the coexistence problems that TDD system needs solution and existed system in addition, increase with the intermediate node cost brought, cost, the workload of maintenance and dilatation besides all can be comparatively large, also can bring the relevant issues such as system reliability.

Though above for Wimax system, there is following shortcoming in wireless access system and the method for other existing in-door covering scene or indoor and outdoor mixing covering scene too:

1) demand for inside plant resource is higher, needs sufficient optical fiber, twisted-pair feeder or coaxial cable distributed system; Part operator (particularly at the multinational operator of emerging market) did not both have fiber resource at most building, did not have twisted-pair feeder resource yet, was difficult to quick networking and reduced lower deployment cost;

2) operator of the existing 2G/3G in-door covering of part, if consider to share existing distributed system, consider the particularity of TDD system, need the significantly transformation of domestic aerial, filter etc., quantities is huge, and transformation can interrupt existing Network, the smooth upgrade of network can not be realized;

3) newly-built independently indoor distribution engineering, disposes difficulty comparatively greatly, also needs to transform existing space structure, there is Engineering concordance difficulty;

4) take Pico BS GP configuring S mode, for big-and-middle capacity in-door covering scene, if dispose multiple Pico BS, huge in installing engineering amount, maintenance cost is also very high.

5) independent Pico BS access point there is problem of management and local maintenance problem, performance of handoffs reduce problem;

6) information interaction of independent Pico BS access point brings efficiency of transmission to reduce;

7) performance bottleneck at centralized network management place and scaling concern time independent Pico BS access point brings performance statistics, edition upgrading;

8) there is dilatation problem, scale and performance issue in indoor distributed system.

Summary of the invention

The another technical problem that the present invention will solve is to provide a kind of synchronous method of layered radio access system, can realize clock synchronous between access point administrative unit and access point, ensures system worked well.

In order to solve the problems of the technologies described above, the invention provides a kind of synchronous method of layered radio access system, be applied to the layered radio access system comprising and be positioned at the access point administrative unit of Access Layer and the access point of lower extension thereof, described access point administrative unit has a timing applications, described access point has a timing client, described timing applications produces timing information and is distributed to the timing client of each access point of lower extension, described timing client recovers described timing information, as the timing reference signal of this locality.

Further, above-mentioned synchronous method also can have following characteristics:

Described timing applications is grouping timing applications and ToP server, and described timing client is grouping timing client and ToP client; The timing reference signal that described ToP server is used for exporting according to GPS receiver module or external synchronization clock source produces hardware timestamping, according to the address information of each access point, send grouping timing information bag to each ToP client by the network interface of described access point administrative unit side and access point side; Described ToP client recovers timing information after receiving described timing information bag, and sends to the base band in described access point and radio-frequency module, as the timing reference signal of described base band and radio-frequency module.

Described access point administrative unit is the main access point administrative unit with IAD function, described main access point administrative unit and and its lower to hang between access point with the communications cable or power line as transmission medium; Or

Described access point administrative unit comprise the main access point administrative unit with IAD function and be connected with described main access point administrative unit one or more from access point administrative unit, the main access point administrative unit be directly connected with lower extension access point and have power line modulation /demodulation function from access point administrative unit, adopts power line as the transmission medium of the lower extension access point to directly connection.

In described timing applications with timing client be identical with real time business by the service quality QoS type configuration of described timing information or higher than the priority of real time business, perform scheduling strategy corresponding to this QoS type in access point administrative unit and access point side respectively, carry out timing information distribution and route according to requirement that is identical with real time business or that be better than real time business.

Between described access point administrative unit and access point, realize flow control mechanism end to end, time asynchronous between access point and access point administrative unit, just start described flow control mechanism, after synchronization, then send data according to normal flow.

Further, above-mentioned synchronous method also can have following characteristics: described layered radio access system also adopt in the method for following raising net synchronization capability one or more:

During power-up initializing, the timing applications in described access point administrative unit hangs access point transmission timing information data with the shortest little wrapping in subnet downwards with the form of broadcast;

Newly add the access point of network at initial access state, only and between described access point administrative unit transmit basic timing information bag and state configuration information; Described access point administrative unit is according to the feedback of access point Synchronization Status Message, and whether control access point can normal electrifying startup;

Adopt the shake in the algorithm filtering Ethernet of loosely coupled PLL, narrow band loop device and sef-adapting filter and float; Adaptive maintenance HOLDOVER algorithm is adopted automatically to detect the synchronizing quality at networking, and the controling parameters under automatic Memory net synchronization capability optimal situation; When network quality worsens, automatically switch to holdover state, utilize the controling parameters of memory to refresh current controling parameters;

Described access point administrative unit, when all node-node transmission data bandwidth occupation rates are lower than the threshold value set, regulates the transmission frequency of ToP infomational message, optimized synchronization performance;

Realize the continuous measurement of speed in described access point administrative unit, do not having under congestion situation, normal route data packets is to each access point, once congested generation, implements the packet drop mechanism based on strategy, and ensures that the business of high priority obtains performance guarantee.

The another technical problem that the present invention will solve is to provide a kind of flow control methods of layered radio access system, can control flow, ensures system worked well.

In order to solve the problems of the technologies described above, the invention provides the flow control methods in a kind of layered radio access system, described layered radio access system comprises and is positioned at the access point administrative unit of Access Layer and the access point of lower extension thereof, and this flow control methods comprises:

When media packet data bag arrives described access point administrative unit, packet is classified and marks, enter the queue of each access point according to destination address and be sent to corresponding access point, and set up flow control end to end between described access point administrative unit and each access point.

Further, above-mentioned flow control methods also can have following characteristics:

Described access point administrative unit is provided with the guarantee bandwidth sum maximum available bandwidth of the down link of each lower extension access point;

When the flow of described access point administrative unit to down link controls, identify and add up the flow based on each lower extension access point, if the statistic flow of its lower extension access point is in the guarantee bandwidth range of setting, then the data of normal storage and this lower extension access point of forwarding; Ensure bandwidth range if its lower statistic flow hanging access point is greater than but is less than maximum available bandwidth, weighted fairness algorithm is then taked remaining bandwidth to be distributed to the lower extension access point queue of overload, if the statistic flow of lower extension access point still overloads afterwards, then preferentially abandon the packet of power BE service queue as possible of this access point.

Described access point administrative unit is provided with the guarantee bandwidth sum maximum available bandwidth of the up link of each lower extension access point;

The flow of described access point to up link controls, and when distributing each end user bandwidth by upstream bandwidth, ensures that the uplink traffic of distributing is no more than described maximum available bandwidth;

When described access point administrative unit detects that total upstream bandwidth exceedes the load threshold of its disposal ability, the access point exceeding up guarantee bandwidth to uplink traffic sends flow control message, is reduced in the scope of described guarantee bandwidth by upstream bandwidth after described access point receives described flow control message.

The another technical problem that the present invention will solve is to provide the dispatching method based on synchronous regime in a kind of layered radio access system, can reduce the requirement to synchronization accuracy, improves system robustness.

In order to solve the problems of the technologies described above, the invention provides the dispatching method based on synchronous regime in a kind of layered radio access system, described layered radio access system comprises and is positioned at the access point administrative unit of Access Layer and the access point of lower extension thereof, and this dispatching method comprises:

Described access point configures the scheduling mode of multiple synchronization state and correspondence thereof, and is configured with the decision condition relevant to timing accuracy of each synchronous regime;

After described access point receives the packet of the timing information of described access point administrative unit distribution, recover timing information wherein and detect current timing accuracy, determine current synchronous regime in conjunction with described decision condition, then carry out uplink and downlink scheduling according to the scheduling mode that current sync state is corresponding.

Further, above-mentioned dispatching method also can have following characteristics:

Described synchronous regime comprises lock-out state, free-running operation and at least one intermediateness, and timing accuracy corresponding to described intermediateness is between lock-out state and free-running operation;

Described access point determine current synchronous regime be timing accuracy meet the demands lock-out state time, carry out normal uplink and downlink scheduling;

Described access point determine that current synchronous regime is the free-running operation that cannot normally work and there is adjacent area in it time, turn off transceiver, but the link maintained between this access point and affiliated access point administrative unit normally works;

Described access point determine that current synchronous regime is intermediateness and there is adjacent area in it time, up, be not up state by a last n sign flag, n=1,2,3....

Described intermediateness is at least divided into again the first state and the second state, and described second state is the state entered after the first state maintains the cycle of a setting;

Described access point determine that current synchronous regime is the first state and there is adjacent area in it time, in upper last or the multiple sign flag of being about to for not up state, dispatch normally descending;

Described access point determine that current synchronous regime is the second state and there is adjacent area in it time, be about to last N number of sign flag for not up state upper, under be about to maximum transmission power and be set to derate state.

Described access point is when judging that timing accuracy is greater than or is more than or equal to a timing precision threshold, or after described second state maintains the cycle of another setting, judges freedom of entry oscillatory regime.

Described layered radio access system is WiMAX tdd systems, and described access point is femto base station and Pico BS, n=1.

When described access point starts, first do not comprise power-on self-test and the normal boot process of the minimum system of transmitter section, then detect current synchronous regime according to the convergence situation of timing client timing algorithm and marked;

Afterwards, described access point timing carries out detection and the renewal of synchronous regime, carries out renewal and the execution of scheduling strategy according to the current sync state detected simultaneously.

Synchronous regime is also reported affiliated main access point administrative unit by described access point, the neighboring BS information of each access point is informed to the access point of lower extension by described main access point administrative unit, and described neighboring BS information comprises the Synchronization Status Message that whether there is adjacent area and adjacent area.

The another technical problem that the present invention will solve is to provide the distributed network management system in a kind of layered radio access system, can be inner at localized network by most of flow control, saves webmaster and transmission bandwidth.

In order to solve the problems of the technologies described above, the invention provides the distributed network management system in a kind of layered radio access system, comprising Element management system and network management center, wherein:

The Access Layer network element that described network management system manages is based on layer architecture, comprise and be positioned at the main access point administrative unit of Access Layer and the access point of lower extension thereof, described network management system comprises and resides in the first OAMAgent module in main access point administrative unit and resident the second OAMAgent module on an access point, wherein:

Described first OAMAgent module be used for and the access point of Element management system and lower extension mutual, realize the Network Management Function of the access point to this main access point administrative unit and lower extension thereof;

Described second OAMAgent module is used for described access point administrative unit mutual, realizes the Network Management Function to this access point.

The another technical problem that the present invention will solve is to provide the distributed network management in a kind of layered radio access system, can reduce the load of Element management system and backbone network, improves the Performance And Reliability of network management simultaneously.

In order to solve the problems of the technologies described above, the invention provides a kind of network management based on above-mentioned network management system, in main access point administrative unit side and access point side achievement unit subnetwork management function, described main access point administrative unit and Element management system Internet management information, realize the Network Management Function to this main access point administrative unit, simultaneously described main access point administrative unit with and lower extension access point Internet management information, realize the Network Management Function of the access point to lower extension.

Further, above-mentioned network management also can have following characteristics:

Described network management comprises administering and maintaining of software version, the administering and maintaining of described software version comprise in following process one or more:

At described main access point administrative unit and each access point, preserve its system configuration data with document form, described file is imported and derives operation, also preserve the copy of described file at Element management system;

Operation maintenance personnel are configured described main access point administrative unit and access point and upgrade at the scene, and the new configuration file of formation uploads to Element management system;

Operation maintenance personnel upgrade at the long-range version to described main access point administrative unit and/or access point system, the content of redaction is issued to the main access point administrative unit of target by Element management system unification, and controlling version distributed and activation process, the content of the redaction relevant with access point is issued to the access point of lower extension again by described main access point administrative unit;

Operation maintenance personnel, in long-range employing virtual private net mode access network element management system client or the system configuration directly checking described main access-in management unit in Element management system client, upgrade system configuration;

Described main access point administrative unit stores two system versions, when remote update failure, automatically rolls back to previous available edition.

Described network management comprises performance statistics, described performance statistics comprise in following process one or more:

Mount the ruuning situation of the service wireless resource into dot system under described main access-in management unit real-time collecting, dynamically observe and tracking system resource and customer service service condition;

Described main access-in management unit checks the applicable cases of radio frequency resource on certain access point, checks and upgrades radio-frequency emission power;

Described main access-in management unit is according to the ruuning situation of Radio Resource in performance statistic, automatically carry out data analysis: if certain access point occur in durations wireless resource utility efficiency overload and congested, then send power system capacity alarm notification to Element management system.

Described network management comprises warning information process, described warning information process comprise in following process one or more:

Hang the system running state information of access point under described main access-in management unit real-time collecting, once detect exception, abnormal information is recorded to file and abnormal data is uploaded to Element management system; Described Element management system is according to relevant alarm and abnormal reporting information diagnostic system mistake;

Between described main access-in management unit and described Element management system arrange have alarm shield function filter, the shielding of non-emergent warning information is stored at described main access-in management unit, only has great alert options just to notify described Element management system;

The main access-in management unit of described Element management system poll appointed area, described main access-in management unit is in stipulated time reporting fault information.

The another technical problem that the present invention will solve is to provide the frequency allocation method in a kind of layered radio access system, can realize main access point administrative unit assist under frequency automation configuration and management.

In order to solve the problems of the technologies described above, the invention provides the frequency allocation method in a kind of layered radio access system, described layered radio access system comprises and is positioned at the access point administrative unit of Access Layer and the access point of lower extension thereof, and this frequency allocation method comprises:

After access point startup and normally work, to affiliated access point administrative unit application frequency resource;

Described access point administrative unit, according to the neighbouring relations between each access point, is determined candidate's frequency of each access point and sends to corresponding access point;

After access point receives the candidate's frequency of oneself, the signal quality of described candidate's frequency is detected, do not pass through if detected, notify that described access point administrative unit reselects frequency, return previous step, pass through if detected, enter normal workflow, terminate.

Further, said frequencies distribution method also can have following characteristics:

When described access point starts, first carry out the power-on self-test of minimum system and normally to start, be then initiated to described access point administrative unit handshake authentication flow process, apply for legal frequency resource; After receiving candidate's frequency that affiliated access point administrative unit issues, open receiver and carry out received signal strength indicator and RSSI input, if the interference signal of described candidate's frequency is less than or is less than or equal to predetermined threshold value, then judge that detection is passed through, otherwise, judge to detect and do not pass through.

Described access point administrative unit is when taking part to use subchannel segmentation and PUSC Segment mode networking, in the following ways for access point selects candidate's frequency and segmentation: the Neighboring Cell List first obtaining each access point, choose the simplest access point of neighboring BS relationship, for its Stochastic choice frequency and segmentation, then be the access point selection frequency in its Neighboring Cell List and segmentation, for access point that is adjacent and that can occur to disturb distributes different frequencies and segmentation, be followed successively by each access point in a manner described and select candidate's frequency and segmentation.

Described access point administrative unit is when there being newly-increased access point, the adjacent area frequency point information of this newly-increased access point and alternative frequency resource is obtained, for described newly-increased access point selects a frequency different from the adjacent area frequency of this newly-increased access point according to the neighborhood region correlation chart of newly-increased access point.

Described access point administrative unit is when taking part to use the whole subchannel of subchannel and PUSC All subchannel mode networking, in the following ways for access point selects candidate's frequency: the Neighboring Cell List first obtaining each access point, choose the simplest access point of neighboring BS relationship, for its Stochastic choice frequency, then be the access point selection frequency in its Neighboring Cell List, for access point that is adjacent and that can occur to disturb distributes different frequencies, be followed successively by each access point in a manner described and select candidate's frequency.

Described access point administrative unit preserves lower frequency point information of hanging access point, under mount and occur abnormal and after restarting, the history frequency point information of preserving this access point is fed back to this access point.

In sum, the technical scheme that the present invention proposes comprises following technological merit:

Support the network management framework of layering, provide AGW-Lite to be integrated in the mechanism of BMU, substantially increase expandability and the network performance of system, be beneficial to witched-capacity network construction.The Delamination Transmission of network management information, and the local routing hanging access point internal information under BMU, most of flow control is inner at localized network, saves webmaster and transmission bandwidth.Improve the impression that user in the area of coverage accesses internal resource, comprise access delay, handover delay and shake, reduce the requirement for transmission;

Interface and form of medium flexibly can be taked between access point and BMU, support the BMU+Pico B/S framework of the medium flexible access such as twisted-pair feeder, optical fiber and power line, be applicable to different application scenarioss, be beneficial to project plan and quick networking, be preferably and adopt power line as transmission medium.When taking the access point based on power line, distributing antenna system for no reason at all can be disposed nearby, not need to increase trunk amplifier, and the transformation of filter.

The ToP clock distribution mechanisms based on BMU layer architecture can be adopted, access point shares the gps clock of BMU configuration, support that timing information is by twisted-pair feeder, cable, optical fiber or even power line transmission, in the recovery of access point completion timing information, configure GPS module without the need to each access point and fix up an aerial wire, reduce engineering difficulty and cost, reduce CAPEX and OPEX of operator;

Due to the uncertain characteristic that the interference signal of powerline systems is introduced, the present invention can support the quality recovered according to Link State and timing signal, realizes the self-adapting intelligent scheduling mechanism of system, the work of safeguards system stalwartness, greatly improve the adaptive capacity to environment of system, elevator system availability.

The centralized agents function of local network management can be realized on the main BMU of layering, facilitate system maintenance, improve system maintainability, reliability and extensibility by distributed network management

The dual-homed mechanism based on AGW-Lite and centralized ASN-GW can be provided, the reliability of safeguards system; Under normal condition, the Pico BS of in-door covering belongs to AGW-Lite gateway, can automatically switch to the ASN-GW of centrostigma under abnormal conditions;

BMU supports the load monitoring of subordinate Pico BS and management, at networking initial stage configuration PUSCSegment networking mode, can smooth upgrade to PUSC All Subchannel, the expansion of back-up system capacity.

Summary of drawings

Fig. 1 is WiMAX mobile network architecture schematic diagram.

Fig. 2 is the in-door covering network diagram based on conventional P ico B/S framework.

Fig. 3 is based on information source base station+distributed passive antenna system framework in-door covering network diagram.

Fig. 4 is based on information source base station+Distributed Active Antennas system architecture in-door covering network diagram.

Fig. 5 is the WiMAX network structural representation of the embodiment of the present invention based on BMU layer architecture.

Fig. 6 A is the schematic diagram of an embodiment based on the WiMAX access point management system of twisted-pair feeder/optical fiber.

Fig. 6 B is the functional block diagram in Fig. 6 A in BMU.

Fig. 6 C is the WiMAX access point management system schematic diagram of another embodiment based on power line transmission.

Fig. 6 D is another schematic diagram of WiMAX access point management system in Fig. 6 B, particularly illustrates the module composition of master and slave BMU, and from the power line connected mode between BMU and Pico BS.

Fig. 7 is the schematic diagram of the timing subsystem realizing timing mechanism between BMU and Pico BS.

Fig. 8 A is the schematic diagram of the adjacent base station networking of the present invention's application example.

Fig. 8 B is the schematic diagram of the indoor covering system definition required precision based on power line transmission.

Fig. 9 is the frame structure schematic diagram based on 802.16e WiMAX TDD system.

Figure 10 is the schematic flow sheet of the dispatching method of synchronous regime based on power line transmission.

Figure 11 is the schematic diagram of flow control between BMU and Pico BS.

Figure 12 is the schematic diagram of the network management system of WiMAX access point based on layering.

Figure 13 is the charging policy schematic diagram of wireless access system of the present invention.

Figure 14 is the flow chart that the Pico BS automatic frequency of the embodiment of the present invention distributes.

Better embodiment of the present invention

Below in conjunction with accompanying drawing and better embodiment, the present invention will be further described in detail.It should be noted that, though hereafter for WIMAX, but the present invention is not only applicable to WiMAX system, also other TDD based on OFDMA (orthogonal frequency-time multiple access) and FDD system is applicable to, such as LTE (Long Term Evolution, Long Term Evolution), TD-SCDMA (TD SDMA) and UMB (Ultra Mobile Broadband, Ultra-Mobile Broadband) etc., and all wireless indoor soverlay techniques can be widely used in.Applicable scene contains covering limitation scene, capacity constraint scene, realizes flexibly covering from the initial stage smooth upgrade being limited to later stage capacity constraint, and protect existing equipment investment, maintenance upgrade only realizes at BMU centrostigma, reduces maintenance cost.

Before discussion the present embodiment, several concept is had to need clear and definite:

Access point, because emphasis between the area of coverage is indoor, the present embodiment is WiMAX base station, the main mode adopting Pico BS, but also can be the base station of other system or the access point of other form.

Access point administrative unit, the present invention is also referred to as building management system (Building Management Unit BMU), do not belong to existing building management system, be exclusively used in the centralized management functional entity as indoor Pico BS, be integrated with the function of the IAD (Light ASN-GW, hereinafter referred to as AGW-Lite) of low capacity simultaneously.

Layering, refers to that WiMAX overall network is disposed and is divided into CSN, ASN; Several levels such as centralized ASN-GW, distributed AGW-Lite, base station and ustomer premises access equipment are divided into again in ASN inside.

Power line transmission, refers to the powerline network providing ac low-voltage power supply (110VAC/220VAC) in building to room illumination, electrical equipment and aisle.

First the framework of the present embodiment WiMAX access network is described:

Fig. 5 is the WiMAX access network based on BMU layer architecture that the present invention proposes, mainly be applicable to in-door covering scene in the present invention, also be applicable to the indoor and outdoor mixing covering scene of regional area, elaboration below mainly launches to describe for in-door covering primary base station type Pico BS.

As shown in the figure, ASN adopts layer architecture, comprises ustomer premises access equipment CPE 501, access point Pico BS502, access point administrative unit BMU and centralized ASN-GW 507 4 levels; Wherein BMU is divided into again main BMU 503 (Master BMU) and from BMU 504 (Slave BMU), supports from BMU504 by subtending port or the mode extended network scale directly accessing main BMU 503.Pico BS and main BMU 503 and from the R6 interface between BMU 504 being standard, (R3 is logic interfacing to adopt the Interface R3 of standard to connect between main BMU503 and CSN206, main BMU and CSN is connected by SDH or PDN network), between multiple main BMU 203 and adopt the Interface R4 of standard to connect (in figure slightly) between main BMU and centralized ASN-GW507.From between BMU 204 and from the R6 interface adopting standard between BMU204 and main BMU 203.Optional from BMU.PDN/SDH505, CSN (connectivity serving network) 506 and centralized ASN-GW 507 is convergence and backbone layer network element.

Various network construction form can be supported more neatly between master and slave BMU, comprise the star net forming structure shown in Fig. 7, and communication link protection, tree-like mixed networking.Adopt the communications cables such as optical fiber, twisted-pair feeder, coaxial cable as transmission medium between master and slave BMU of the present invention.The transmission mediums such as optical fiber, twisted-pair feeder, coaxial cable and power line are adopted between master and slave BMU and PicoBS.

Because ASN-GW belongs to centrostigma and the Controlling vertex of the protocol terminations of wireless access side, realize RRM, handover management, paging management and and the function such as Routing Protocol process of IP network, generally take in traditional scheme to concentrate the mode of disposing, under which, ASN-GW is positioned at convergence and backbone layer.In the framework of network design, propose the deployment way of layering in the present invention, in the in-door covering region of emphasis, BMU is near base station deployment, and adopt distributed framework, installation site is positioned at Access Layer; BMU is integrated with the ASN-GW functional module (in order to distinguish, hereinafter referred to as AGW-Lite with the ASN-GW of concentrated deployment) of Small And Medium Capacity.The data of BMU to access point process and routing forwarding, also carry out network management to access point.The present invention considers the demand of seamless coverage simultaneously, disposes centralized ASN-GW in convergence-level or backbone layer.

No matter the 4G network in existing 2/3G network or future, the important area that indoor service traffics often occur, in the statistics of existing network, NTT DoCoMo shows that in user distribution, indoor use has accounted for 70%; And the behavior of this part indoor user is generally static, low speed moves; Adopting the mode of distributed deployment AGW-Lite, belonging to data between base station that same main BMU (comprise its cascade from BMU) manages and chain of command Signalling exchange directly by BMU process with forward, without the need to being routed to center CSN node.By WiMAX protocol terminations at each access point building, directly access IP data network, greatly can reduce the capacity requirement concentrated and dispose ASN-GW.

Cover building or group user for enterprise network, emphasis, the important area of service traffics generation often, in intranet user, the flow of significant proportion occurs between the interior user of net simultaneously; According to the data flux statistics of ZTE Corporation's internal enterprising network, nearly the flow generation enterprise network of 50% is inner; Network service adopts the BMU framework of layering and the deployment of AGW-Lite, and by WiMAX protocol terminations at each access point building, the digestion of this partial discharge is inner at AGW-Lite, decreases the pressure for transmission network.If take traditional centralized ASN-GW deployment scheme, the taking of transmission bandwidth will to increase by 50% nearly with operating cost.

The present invention supports that Pico BS can be dual-homed to AGW-Lite and centralized ASN-GW, improves the reliability of system; Under default conditions, Pico BS belongs to the built-in AGW-Lite of BMU; When AGW-Lite fault, the flow of Pico BS identifies fault automatically by the mode of online R6 link detecting, is switched to centralized ASN-GW.

Fig. 6 A is by the BMU deployment solution under scene, for the FDD system of WiMAX, and the wireless access system of other non-WiMAX, also can realizing with this framework of Fig. 6 to access point based on twisted-pair feeder/fiber resource of proposing of the present embodiment.

This wireless access system mainly comprises Pico BS 601, the main access point administrative unit BMU603 concentrated, connected by the LAN (comprising switch 602a) of inside buildings between Pico BS 601 and main BMU 603, the R6 interface of employing standard, physical interface can adopt electrical interface or optical interface, and physical rate can be 100Mbps or 1000Mbps.Bearing medium can be optical fiber, also can be twisted-pair feeder.Under this solution, only need configuration BMU 603, i.e. main BMU, the expansion between network can adopt general switch, does not need configuration from BMU.BMU 603 is generally deployed in the building at place, WiMAX base station nearby as in building, but this is only an example, and BMU mounts under also can being deployed in an accessible place of cable resource.In addition, for smaller and adjacent building, also a BMU can be set in multiple building.

As shown in Figure 6B, functional module in this main BMU comprises master control Switching Module 6031, the IAD functional module 6035 be connected with master control Switching Module 6031, divide into groups timing applications (ToP Server, TP and Timing Over Packet) 6033 and centralized network management functional module 6032, the clock source 6034 be connected with ToP server 6033.Wherein:

Master control Switching Module 6031, have and the access point hung under described access point administrative unit and/or the mutual communication interface of other master control Switching Modules, for hanging the data (comprising user face data, clock data etc.) of base station and the process of Signalling exchange and forwarding under completing this BMU.If multiple base station needs the WiMAX channel binding a formation logic, then what master control Switching Module also completed the MAC of this logic channel and layer 3 agreement focuses on function.

Centralized network management functional module 6032, also referred to as OAMAgent module, for completing the Operation and Maintenance information processing of BMU.

Clock source 6034 can be built-in GPS, also can configure other clock module at BMU and replace GPS receiver module, produce timing information, or produce timing information by input external synchronization clock source.Namely this module is optional.

ToP server function module 6033, also referred to as ToP server, for distributing clock information to multiple ToP client.Certain the present invention also can adopt other timing applications.

IAD (AGW-Lite) functional module 6035, also referred to as low capacity IAD, be integrated in main BMU 603 alternatively, its function is similar to centralized IAD, for completing the convergence and tunnel protocol process etc. of base station access information, there is provided Interface R3 to arrive core net CSN and the Internet, provide route handoff relevant information to corresponding centralized IAD simultaneously.AGW-Lite be also responsible for local wireless sources processing capacity and local flow from routing function.AGW-Lite also completes the finalization process for the tunnel process of lower extension base station, for traffic shaping and the flow control of multiple lower extension base station, and based on the data stream scheduling process of base station.

Under this scene, the Pico BS of floor N and floor N+1 is according to user's traffic statistic and deployment, PUSC (Partially Used Subchannel can be adopted, part uses subchannel) configuration mode of Segment (segmentation), also can adopt the configuration mode of the whole subchannel of PUSC; For covering confined area, the networking of PUSC Segment mode can be adopted, improve spectrum utilization efficiency.The subchannel method of salary distribution between Pico BS, automatically can generate according to the relative position relation between Pico BS in BMU side, reduce the engineering opening and preventive maintenance time that configure separately at each Pico BS, be convenient to the economy of operator and quick networking, reduce the OPEX (Operating Expense, operation cost) of operator.

The present embodiment supports that physically separated multiple Pico BS forms logic district group, such as can suppose that Pico BS A, Pico BS B in Fig. 6, Pico BS C form the cell set 1 of logic; Pico BS D, Pico BS E form the cell set 2 of logic, and the Pico BS in cell set shares the different subchannels of same WiMAXChannel (channel), and different districts component joins different WiMAX Channel; BMU carries out the distribution of subchannel according to the position relationship between cell set 1,2 subordinate Pico BS, ensures that the interference between Pico BS A ~ E is reduced to minimum simultaneously.

For covering limited region, Pico base station can also be adopted as information source, coverage is expanded, coupler or radio frequency cable can be adopted to be connected between power splitter 604 with passive distributed antenna system 605 by coupler or power splitter 604 and passive distributed antenna system 605.

Fig. 6 C is that another embodiment disposes schematic diagram using power line as transfer resource to the BMU under access point scene, the possibility based on power line transmission is provided between Pico BS and BMU, form complementary solution with Fig. 6 A, use when being applicable to newly increase the Pico BS access point position routing to planning.

Under this solution, the subtending port of main BMU 603 is connected with one from BMU 602c, should from BMU 602c can also more successively level be associated with one or more BMU 602c, certainly also support other star and tree-like networking mode.From BMU for realize main BMU and this BMU manage the route forwarding function of power line transmission relay function between Pico BS and data, timing information.The multiple available transfer resource interconnection such as optical fiber or twisted-pair feeder is adopted between master and slave BMU.Power line is adopted to be connected between BMU and the Pico BS of its management.The same with a upper embodiment, the present embodiment also supports that physically separated multiple Pico BS forms logic district group, repeats no more here.If when lower mounting point is less, also can not arrange from BMU, directly between main BMU and lower extension access point, power line is adopted to be transmission medium.

Fig. 6 D is also the WiMAX access point management system in Fig. 6 B, particularly illustrates the module composition of master and slave BMU, and from the power line connected mode between BMU and Pico BS.Pico BS 601 can be installed near supply socket 606 nearby, all carries at power line 608 medium from the transfer of data between BMU and Pico BS and power supply.Consider the complexity that indoor power line is disposed, different rooms and floor may access different electricity mutually, and the three-phase electricity under same transformer adopts coupler 607 to be coupled, and is convenient to the fast simple deployment of engineering.

The functional module configured in main BMU comprises: master control Switching Module 6031, the low capacity IAD 6035 be connected with master control Switching Module 6031, ToP server 6033, OAMAgent module 6032 and power line transmission interface module 6036, and the clock source 6034 be connected with ToP server 6033.Compare with the main BMU in a upper embodiment and Fig. 6 B, add a power line transmission interface module 6036, this module modulation /demodulation main equipment realizes, be connected between master control Switching Module and power line, for completing power line transmission function, link detecting and self-adaptive processing function, and provide synchronous regime as the foundation of subsequent treatment to master control Switching Module.In addition, master control Switching Module 6031 need increase the cascade function between BMU on the basis of a upper embodiment.ToP server also can be used for receiving Synchronization Status Message that each ToP client sends and neighbor synchronization state information is distributed to each ToP client.Other functions of modules are see a upper embodiment.

From BMU 602c compared with main BMU 603, do not comprise OAMAgent module 6032 and low capacity IAD 6035, namely the functional module of its configuration only comprises: master control Switching Module 6031, the ToP server 6033 be connected with master control Switching Module 6031 and power line transmission interface module 6036, alternatively, the clock source 6034 be connected with ToP server 6033 is comprised.Each functions of modules is see main BMU.

Based on the above-mentioned network architecture, below synchronous method of the present invention is described in detail.

In order to reduce Pico BS for the requirement of process installation and maintenance and cost, the present embodiment in BMU side GP configuring S clock generating module as GPS, for generation of PP1S (industrial signal measurement conversion device) timing information.By configuring GPS module at BMU, decreasing the installation difficulty and the installation cost that configure GPS in base station side, being conducive to arranging net and reducing initial outlay fast and reduce maintenance cost.The timing information produced is distributed to each Pico BS, Pico BS by Ethernet grouping bag and recovers timing information again.Particularly, for the scene based on power line transmission between BMU and base station, the ToP timing information bag that TOP server sends through master control switch and modulation /demodulation master transmissions to Pico BS.For the scene based on optical fiber or Double-strand transmission between BMU and base station, the ToP timing information bag that TOP server sends is transferred to Pico BS through master control switch and switch.

Fig. 7 is the schematic diagram of the timing subsystem realizing timing mechanism between BMU and Pico BS.Comprise gps clock generation module 701 in BMU 707, ToP server 702, the ToP server module that is connected with gps clock generation module 701 is connected with Pico BS by the network interface 704 of BMU side.The network interface 705 of interconnective Pico BS side between two, ToP receiver module (or being called ToP client) 703 is comprised, base band and radio frequency unit 706 in Pico BS 708, wherein:

Gps clock generation module 701 is as the timing base of whole system, and export timing reference signal to ToP server 702, wherein timing reference signal comprises PP1S signal and other relevant informations (such as TOD, positional information etc.).

TOP server 702 produces hardware timestamping according to timing reference signal, according to the address information of each Pico BS, sends ToP timing information bag to Pico BS by the network interface 704,705 of BMU side and Pico BS side;

The timing information bag that TOP receiver module 703 receives according to Pico BS side network interface 704, carries out shaking, the estimation of time delay, recovers timing signal, exports this timing signal to base band and radio-frequency module, as the timing reference signal of base band and radio-frequency module 706.

In figure, Fs states sample frequency; PP1S represents pps pulse per second signal; Ctrl represents control information, the information such as lock-out state, Link State of such as ToP module.

Above-mentioned timing recovery mechanism decreases the installation difficulty and the installation cost that configure GPS in each base station side, is conducive to arranging net and reducing initial outlay fast and reduce maintenance cost.

Further, the present embodiment can adopt following to one or more in the Optimized Measures of ToP synchronous method.

Network QoS (Quality of Service, service quality) ensures:

In order to ensure that the performance of Top receiver module side clock recovery reaches state that is stable and that optimize, at EMS (Element Management System, Element management system) server side setting QoS default policy time, the message priority that setting is relevant with ToP information is the same with real time data message priority or be set to limit priority, be synchronized to BMU side and Pico BS side, statistical significance ensure time delay and shake are at zone of reasonableness.In ToP module (comprising ToP server and ToP client), mark timing information is the QoS type of specifying, perform the scheduling strategy based on QoS label information at BMU and base station side guarantee respectively, carry out timing information distribution and route according to the requirement of real time business; Set the guaranteed bandwidth of each Pico BS node up-downgoing by webmaster, ensure there is enough bandwidth transmitting ToP information.Meanwhile, can special hardware co-processor be taked extract at Pico BS and process, to reduce the unpredictable time-delay and impact that software brings.

Optimize the convergence rate of ToP:

The impact that current IEEE1588 convergence rate is subject to network load is larger, therefore considers: for the optimization of the convergence rate of TOP, adopt following scheduling mechanism.The means that main employing is following: during power-up initializing, the TOP Server sync packet of BMU side sends with the form of broadcast with the shortest little wrapping in subnet.For such message, master control and the Switching Module processing policy of BMU have precedence over every other business; Simultaneously for the Pico BS node of specifying, as long as asynchronous between BMU side and Pico BS node, with regard to selective actuation flow control mechanism, reduce the shake caused because non-controlling surface information is congested and time delay as far as possible, ensure the transmitting of ToP information, ensure that TOP is when initial synchronisation, the load of network is in rational loading range (60% ~ 70%): also namely can not be subject to network burst message, the impact of network congestion; After synchronous, BMU and Pico BS sends packet according to normal flow.

Newly increase the synchronous processor system of SLAVE node:

Newly add the Pico BS SLAVE node of network in initial access state, only and between main BMU transmit basic ToP infomational message and state configuration information, do not transmit and carry medium surface data, guarantee there will not be congested, acceleration synchronization process; BMU side is according to the feedback of Pico BS Synchronization Status Message, and whether can normally electrifying startup, set up Media Stream passage if controlling base station; Main BMU, according to the net synchronization capability of all nodes in subnet, when all node-node transmission data bandwidth occupation rates are lower than the threshold value set, regulates the transmission frequency of ToP infomational message, optimized synchronization performance.

Adopt the algorithm optimization of digital synchronous phase-locked loop:

Adopt the algorithm of loosely coupled PLL and narrow band loop device and sef-adapting filter, shake large in filtering Ethernet and floating; And adaptive HOLDOVER (maintenance algorithm) algorithm, automatically detect the synchronizing quality at networking.Under network quality deterioration, automatically switch to holdover state.HOLDOVER algorithm adopts study and training method, the controling parameters under automatic Memory net synchronization capability optimal situation.The parameter utilizing these to remember under holdover state, refresh control parameter, makes system reach extraordinary maintenance performance.

The network management of net synchronization capability and treatment mechanism:

Because WIMAX system requires very high, if which node step-out to the net synchronization capability of network.Can because the sequential of TDD be chaotic, cause whole network interferences to increase, performance sharply worsens.Therefore Systematical control adopts the means of each synchronisation of nodes state of monitoring in real time, and webmaster foreground agency, when certain synchronisation of nodes hydraulic performance decline being detected, can adopt exception handling to this node, reduce the transmitting power of this node, contracting coverage radius of cell.The interference to adjacent cells can be reduced like this; At the appointed time, if Network Synchronization performance is not still recovered.To take to automatically shut down base station RF to export, alarm backstage, to notify that the relevant personnel process.

In addition, BMU according to network load situation, can initiate the initialize flow to this subnet abnormal nodes, accelerates its synchronous recovering process when idle (such as period in morning).

Flow control mechanism, will be explained in greater detail below.

In order to effectively complete the management by synchronization for base station, need at BMU local resident and store the neighboring BS information of subordinate base station, TTG (send out and receive change gap) and the information such as RTG (transmitting-receiving change gap) default parameter, base station derate power default parameter, these parameters are handed down to base station by BMU.Regular update Synchronization Status Message between BMU and base station, so that the subordinate base station of BMU is unified realize effective and reliable dispatch deal.BMU assists base station to complete dynamic dispatching, the TDD up-downgoing ratio of unified configurating base station and RTG/TTG time sequence parameter.Under normal circumstances, base station adopts general scheduling mechanism.

As shown in Figure 8 A, BS1 and BS2 is two adjacent indoor base stations, considers that the interference of identical networking adjacent area is inevitable, recommends the mode adopting inter-frequency networking; First suppose that each base station operation is in different frequencies, base station BS 1 is operated in f1 frequency, and base station BS 2 is operated in f2 frequency; MS1, MS2 are two terminal uses being in adjacent area, and MS1 accesses at BS1, and MS2 accesses at BS2.If base station BS 1 and BS2 is asynchronous or synchronization accuracy is lower, may occur that neighbor base station signal interferes with each other or even interfering with each other between terminal, cause system normally to work.

Described interference is divided into two types:

(1) clutter interference of neighbouring device, causes the sensitivity of adjacent base station to decline;

(2) strong jamming of neighbouring device, causes receiver to block because equipment room is asynchronous.

Concrete interference can be subdivided into following several situation:

(1) base station BS 1 causes descending interference for MS2;

(2) base station BS 1 causes the interference of uplink receiving link for BS2;

(3) base station BS 2 causes descending interference for MS1;

(4) base station BS 2 causes the interference of uplink receiving link for BS1;

(5) the transmitting-receiving interference between MS1 and MS2.

According to the situation analysis of various networking, 802.16e RCT test specification requires that the timing accuracy of adjacent base station can reach +/-1 μ s, and this just requires that all base stations must configure GPS.For in-door covering scene, be difficult to accomplish that GPS and antenna system are all disposed in all base stations.The concrete condition of covering scene in analysis room: indoor covering system, multipath transmisstion is abundanter, but multidiameter delay is general all smaller, and interval at 100m according to in-door covering radius, multidiameter delay is generally at 5 below μ s.According to RCT test specification regulation, for 5/10MHz system, RTG is arranged according to 60 μ s, and TTG is arranged according to 105.7142857 μ s, suitably can reduce the timing accuracy requirement of in-door covering base station like this, at least can be reduced to +/-20 μ s required precision.

In +/-20 μ s required precision situation, ToP method can be adopted to transmit between BMU and base station and recover timing information.When based on Ethernet transmission ToP timing information, timing can reach the precision of +/-(1 ~ 5) μ s, in link degradation situation, also in +/-20 μ s accuracy rating, can meet the requirement of systematic function and networking.Based in power line transmission ToP timing information situation, systematic function want relative complex some, link under normal circumstances, timing can reach the accuracy rating of +/-20 μ s, when link quality degradation, may in +/-(30 ~ 50) μ s accuracy rating, in this case, the RTG specified at RCT may cause system normally to work under being 60 μ s situations.As shown in Figure 8 B, although base station B1 and B2 uses different frequencies, consider the design principle of base station prefilter, when particularly an operator has continuous print frequency spectrum, the filter of B1 and B2 all can adopt the broadband filter of continuous bandwidth, up may the causing of MS2 is disturbed in the band to BS1, and that greatly can reduce system under serious conditions accepts sensitivity.

Fig. 9 illustrates based on the frame format of 802.16e WiMAX TDD system.Frame format is according to time and frequency (subcarrier) two dimension definition.According to time dimension, in 802.16e agreement, a frame has the optional definition of the frame lengths such as 2ms, 5ms, 10ms usually.According to different channel width (such as 5MHz, 10MHz), there is again different number of subcarriers definition (512 corresponding 5MHz bandwidth of subcarrier, 1024 corresponding 10MHz bandwidth of subcarrier).Subcarrier is according to certain displacement patterns composition groups of subchannels, and 1 sub-channels comprises the number of subcarriers of some, and such as 10MHz, 1 downlink sub-channels comprises 24 data subcarriers, 4 pilot sub-carriers, and available subchannel data is 30; Uplink frame is 35 sub-channels, every sub-channels 24 subcarriers; Up-downgoing is remaining is all protection subcarrier.

Owing to being TDD system, same channel up-downgoing adopts same frequency, takes time division multiplexing mode, and according to different symbols ratio, the symbol bandwidth of up-downgoing is different.Consideration system and end-on needs, transceiver devices function pattern switch the characteristics such as needs and radio transmission, the base station transceiver signal transition period, need to reserve RTG and TTG, so that the normal switch operating of system.At 802.16e RCT (Radio Conformance Test Specification, RF consistency test specification) in, regulation is for 5/10MHz system, and RTG is arranged according to 60 μ s (microsecond), and TTG is arranged according to 105.7142857 μ s.

As shown in the figure, in downlink frame, first symbol is Preamble prefix area, and system fixed overhead uses for terminal synchronizes; Downlink frame, under PUSC (part uses sub-channelizing) displacement patterns, except first preamble region, other regions form a Slot time slot according to 2 symbol * 1 sub-channels; Slot is the base unit that downlink system carries out multi-subscriber dispatching; According to size and the qos requirement of difference PDU to be transmitted (protocol Data Unit), system assignment is combined into different descending Burst (burst), meets system performance requirements.Uplink frame, adopts similar mode, only under up PUSC displacement patterns, forms a Slot time slot according to 3 symbol * 1 sub-channels.

Based under the scene of power line transmission, adopt the self adaptation uplink scheduling algorithm optimized, based on the flow control mechanism of base station and BMU, and QoS is machine-processed end to end between base station and BMU, can in signal quality deteriorates situation, marking last N number of symbol is down state, avoids in the end N number of symbol slot section distributing terminals to launch up burst Burst signal.So, maximum system transmitting-receiving protection is spaced apart Min (TTG, RTG+N*T _symbol), reduce the requirement for timing precision, thus avoid the probability that between terminal, between terminal and base station, disturbed condition occurs, ensured the reliability of timing information, substantially increased the robustness of system.

For the 802.16e system of 5MHz/10MHz, under adopting 5ms frame condition, in 1/8CP (Cyclic Prefix) situation, T _symbolbe 102.8571 μ s; If symbol is more descending than adopting: in upper behavior 31: 16 situation, desirable N=1 namely protects and is spaced apart Min (TTG, RTG+1*T _symbol)=TTG=105.7142857 μ s; Removing outside 1 uplink symbol free time do not dispatch, can also have the scheduling of descending 31 symbols and up 15 symbols, meet PUSC displacement patterns, uplink spectrum efficiency aspect there is no large change simultaneously.For other symbols than in situation, N value can also get larger value, but meaning is little, and TTG has limited further expanding of protection interval.After adopting adaptive scheduling algorithm, the tolerable maximum timing accuracy of base station system can reach 50 μ s, substantially increases the antijamming capability of system.

Figure 10 is an example of the dispatching method based on power line clock recovery performance.First to configure the scheduling mode of multiple synchronization state and correspondence thereof on base station, and the decision condition relevant to timing accuracy of each synchronous regime need be configured.In this example, be divided into multiple by the synchronous regime (synchronous regime also referred to as base station) of base station timing client clock restore circuit, the method for each state and judgement thereof is as follows:

If timing algorithm Complete Convergence, timing accuracy (the convergence situation according to timing algorithm can calculate timing accuracy) is better than t ₁(t ₁default to 20 μ s), be judged to be lock-out state, now base station is synchronous with BMU in other words, as being other state, then thinks that base station is asynchronous with BMU;

If timing algorithm is non-Complete Convergence also, timing accuracy is worse than t ₁but, be better than t ₂(t ₂> t ₁, t ₂default to 50 μ s), be judged to be the lock-out state that degrades;

The lock-out state that degrades maintains some cycles T ₁afterwards, judge to enter hold mode;

Hold mode maintains another certain cycle T ₂afterwards, freedom of entry oscillatory regime is judged.

If timing accuracy is worse than t ₂, directly judge freedom of entry oscillatory regime.

As shown in Figure 10, the dispatching method of power line clock recovery performance comprises the following steps:

Steps A 10, time base station initiated, first carries out power-on self-test and the normal boot process of minimum system, transmits comprising employing ToP method and recovers timing information between BMU and base station;

Minimum system does not comprise the transmitter section of base station, adopts irrational frequency to produce interference to other base stations when mainly preventing from powering on.

Steps A 11, after minimum system normally works, the synchronous regime of ToP client is detected in base station, if be in the lock state, goes to step A12, otherwise goes to step A13;

Steps A 12, is labeled as lock-out state by synchronous regime, then performs steps A 18;

Steps A 13, base station judges whether the synchronous regime of ToP client is the lock-out state that degrades, if be the lock-out state that degrades, goes to step A14, otherwise goes to step A15 further;

Steps A 14, is labeled as synchronous regime the locking that degrades, and scheduling mechanism is set to conservative scheduling, performs up conservative scheduling flow, then performs steps A 18;

Steps A 15, judges whether the synchronous regime of ToP client is hold mode further, if be hold mode, go to step A16, otherwise goes to step A17;

Steps A 16, is labeled as maintenance by synchronous regime, and scheduling mechanism is set to conservative scheduling, performs up conservative scheduling flow, then performs steps A 18;

Steps A 17, is labeled as free-running operation by synchronous regime, and Base Transmitter link defaults to shutoff, maintains R6 interface network link communication normal, timely report and alarm information, so that network management personnel carries out fault location and system maintenance, performs steps A 18;

Steps A 18, state information report is given main BMU by base station simultaneously, and the neighboring BS information of this base station is informed to the base station of subordinate by main BMU, and described neighboring BS information is except with or without except the information of adjacent area, also can comprise neighbor synchronization state information, for the Synchronization Status Message of synchronous adjacent base station;

Base station, after receiving neighboring BS information, performs following flow process:

Steps A 19, judges whether this base station is in the lock state, if so, then goes to step A20, otherwise go to step A21;

Steps A 20, carry out normal uplink and downlink scheduling flow, all uplink symbol are upstate, and receiving-transmitting chain normally works, and then perform steps A 27;

Steps A 21, judges whether this base station has adjacent area further, if not, goes to step A20, otherwise go to step A22;

Steps A 22, judges whether base station is the lock-out state that degrades, and if it is goes to step A26, otherwise goes to step A23 further;

Steps A 23, judges whether base station is in hold mode, if it is goes to step A24 further, otherwise goes to step A25;

Steps A 24, arranging maximum transmission power is derate state, such as reduces 6dB (decibel), and specific strategy can configure on backstage, then performs steps A 26;

Steps A 25, if system is neither be operated in island state, synchronous regime is again free-run mode, then turn off transceiver, maintains R6 interface link and normally works, and return steps A 11 and continue to perform, waiting system recovers normal;

Steps A 26, base station down scheduling flow is normal, and up last N number of sign flag be not up state, enters up conservative scheduling flow, then execution steps A 27;

Steps A 27, continues monitoring system clock status, returns steps A 11.

In above-mentioned steps A19, A22, A23 and A25 after judging the synchronous regime of base station, if different from the synchronous regime before base station, also tackle synchronous regime and upgrade.

Above-mentioned state-detection is that timing is carried out, and is the minimum execution cycle frame by frame, carries out renewal and the execution of dispatch deal strategy.

Realize above-mentioned scheduling, the TOP client in access point need comprise:

Configuration information storage unit, for the scheduling mode information of the multiple synchronization state and correspondence thereof of preserving configuration, and the decision condition relevant to timing accuracy of each synchronous regime;

Timing signal recovery unit, for recovering timing signal according to the timing information bag received, exporting base band and radio-frequency module to, exporting the convergence situation of timing algorithm to synchronous regime identifying unit simultaneously;

Synchronous regime identifying unit, determines current timing accuracy for the convergence situation according to timing algorithm, in conjunction with the synchronous regime decision condition arranged, determines current synchronous regime and outputs to dispatch control unit;

Dispatch control unit, for determining corresponding scheduling mode and performing according to current synchronous regime.

As can be seen from above-mentioned dispatching method example, under power line transmission continuous quality abnormal conditions, base station there will be the decline of timing accuracy, in this case BMU side United Dispatching strategy, coordinate the scheduling mechanism of the WiMAX base station of administration, ensure that the interference between base station is reduced to minimum, ensure transmission reliability.Hang the service feature improvement between base station under BMU, greatly improve the KPI (Key Performance Indicator) of in-door covering network, comprise time delay minimizing, shake minimizing and handoff and deadline minimizing, promote user satisfaction.Under local timing's precision extreme degradation or unavailable situation, take reduce transmitting power or even turn off base station manner, avoid the decline causing global network quality.

It should be noted that, above-mentioned state is arranged and corresponding scheduling mode is only a kind of example, in other embodiments, also can to lock degrading and hold mode is combined into one, in this case by up last N number of sign flag for using.And the title of above state is also not limited to the title of above-described embodiment, because title is just in order to distinguish the different state of several timing accuracy.

Flow control

For the scene based on power line transmission, consider that the Pico BS hung from BMU is actually the mechanism (such as TDMA or CSMA technology) of shared powerline bandwidth, and there is the possibility of bursty interference.And between BMU and network side, be healthy and strong transmission network, therefore between R3/R4 interface and R6 interface, there is potential asymmetric feature in high bandwidth and high reliability.If under certain Pico BS exists larger burst flow situation, the flow of other base stations hung under may blocking BMU, causes periods of network disruption.

In order to ensure timing information, chain of command information and the user plane information performance at Ethernet and power line transmission better, need to support flow control function at main BMU and Pico BS, and the coupling of the strategy definition of synchronous ethernet QoS and power line QoS, ensureing can the reliable and prioritised transmission of effective guarantee ToP packets of information in the treatment mechanism of power line network and ethernet network.According to system index and performance requirement, at BMU side and Pico BS side configuration flow control parameter, and the parameter such as configuration timing, chain of command, QoS information that user face data is corresponding.Flow control end to end can be realized at Pico BS and BMU side; Test proves, after realizing flow control mechanism, can be good at the transmission performance ensureing R6 interface; Can be good at the transmission performance ensureing timing information simultaneously.

The method of flow control between BMU and Pico BS is described below by an example.Figure 11 shows that BMU and Pico BS flow control schematic diagram.BMU takes the fairness doctrine, ensures lower equalization of hanging Pico BS shared network bandwidth opportunity, and under network congestion, ensures that the business of high priority obtains performance guarantee.When media packet data arrives BMU, packet is classified and marks, and enters the queue of each Pico BS according to destination address.Realize the continuous measurement of speed at the distribution module of BMU, do not having under congestion situation, normal route data packets is to each Pico BS; Once congested generation, implement the packet drop mechanism based on strategy, specifically describe as follows:

Up link and the down link guarantee bandwidth sum maximum available bandwidth separately of each Pico BS base station are set in EMS side;

Flow control for down link performs in BMU side, and BMU identifies and adds up the flow based on each Pico BS base station, if the statistic flow of Pico BS is in the guarantee bandwidth range of setting, and normal storage and the data forwarding this Pico BS; Ensure bandwidth range if the statistic flow of Pico BS is greater than but is less than maximum available bandwidth, weighted fairness algorithm is taked to distribute to the Pico BS queue of overload according to the maximum residual bandwidth of BMU statistics (as equal the descending maximum of BMU and deduct BMU and use downlink bandwidth, or equal to deduct after descending maximum is multiplied by a load threshold in units of percentage to use downlink bandwidth); If the flow of this Pico BS still overloads, preferentially abandon the data message of this base station BE (doing one's best) service queue;

Bandwidth for up link controls to perform at Pico BS, the same downlink processing of basic principle, unlike: when Pico BS distributes each end user bandwidth by upstream bandwidth, the uplink traffic that strict guarantee distributes is no more than maximum available bandwidth.If BMU side finds that the load threshold that total upstream bandwidth exceedes its disposal ability (configures by EMS, according to algorithm simulating and actual test empirical value, generally be set to 70% ~ 75% interval proper) time, identify the candidate Pico BS list exceeding up guarantee bandwidth, send flow control message to the Pico BS in list, in Pico BS side, bandwidth is reduced in the guarantee bandwidth range of setting.

Through actual test verification, based on the flow control policy of BMU and Pico BS, can effectively avoid the congested of whole net, substantially increase the robustness of system.

Network management

Figure 12 is the WiMAX access point network management system based on layering.Due to indoor covering system, often a website (such as skyscraper, CBD Business Building) needs deployment more than 10 even dozens of Pico BS 801; A city often needs to dispose up to ten thousand Pico BS; Traditional network management framework takes centralized architecture: EMS (Element Management System, Element management system) server is positioned at central machine room, considers that reliability takes the backup configuration mode of long-distance disaster; Consider the autgmentability of performance, take the high performance EMS server of multiple stage to take the mode of load sharing to realize cascade and expansion.If network network management scheme traditionally, the performance requirement for centralized network management is high, comprises processing capability in real time, network storm rejection ability and storage capacity.

The present invention proposes a kind of distributed network management system, based on the BMU framework of layering, in BMU and Pico BS side achievement unit subnetwork management function.

Network management of the present invention divides four parts, the local network management function (being realized by the OAMAgent module on Pico BS) of Pico BS, the local centralized network management agent function module (being realized by the OAMAgent module of BMU) of BMU, the network management function of EMS server side, and the NMC of network management center (Network Management Center, network management center) network management function.

In order to reduce the requirement of Pico BS Operation and Maintenance for EMS server, on BMU and Pico BS foreground, resident OAMAgent module realizes OAMAgent function, OAMAgent module on BMU be used for and the OAMAgent module of EMS and lower extension access point mutual, realize the Network Management Function of the access point to this main access point administrative unit and lower extension thereof.OAMAgent module on described Pico BS is used for BMU mutual, realizes the Network Management Function of this access point.Described Network Management Function comprise in performance statistics, the administering and maintaining of software version, warning information process, the function such as configuration management and failure diagnosis one or more.Wherein:

Version management and maintenance mainly comprise following several aspect:

1) preserve its system configuration data with document form in BMU and each Pico BS, this file can be imported into and derive.Long-range operation maintenance system and EMS and NMC preserve the portion copy of this file, and operation maintenance personnel can be configured BMU and Pico BS at the scene, have configured the configuration file that rear formation is new, and this configuration file will be uploaded in EMS.In addition, operation maintenance personnel also long-range employing VPN mode can access EMS client in machine room local network management and figure, or check the system configuration of BMU in EMS client, if the system configuration of BMU has problem, can long-rangely upgrade system configuration.

2) BMU operation maintenance system provides local and remote version updating function.Operation maintenance personnel can upgrade to the version of system at the scene, also can the system version of remote update BMU.BMU is upper can store two system versions, and when remote update failure, BMU, by automatically rolling back to previous available edition, greatly enhances system availability.

3), during remote update version, issue the content of redaction to target BMU by EMS unification, and control version distributed and activation process.

The network management framework of layering, relative to traditional integrated network management system framework, improves the efficiency of upgrading, is with 10000 Pico BS, according to the access point architecture of layering, supposes there is 500BMU under such as EMS, is with 20 Pico BS under each BMU; If EMS directly supports the edition upgrading for 10000 base stations, need distribution 10000 parts of edition datas; And the network architecture of layering, only need distribution 500 parts of edition datas.After being issued to BMU, the content of the redaction relevant with Pico BS is issued to the Pico BS of lower extension again by BMU; Load for backbone transport network decreases 95%, and the local area network (LAN) most load being controlled to form at BMU and Pico BS is inner, and the inner bandwidth often of local area network (LAN) is had more than needed and QoS can ensure; Therefore Performance And Reliability is substantially increased from version management angle analysis.

Performance statistics mainly comprises:

1) BMU can hang the ruuning situation of the service wireless resource of base station system under real-time collecting, dynamically observes and the business service condition of tracking system resource and user, is convenient to the control and management to system resource.

2) BMU can check the applicable cases of radio frequency resource on certain Pico BS, checks and upgrades radio-frequency emission power, suitably can adjust coverage according to networking requirements.

2) according to the ruuning situation of Radio Resource in above-mentioned performance statistic, BMU carries out data analysis automatically: if in durations, (this cycle configures by EMS in certain base station, default recommendation is 7 ~ 15 days) occur wireless resource utility efficiency overload and congested, send power system capacity alarm notification, be convenient to the important decision foundation whether network manager optimizes radio-resource-configuration.

Warning information pack processing contains:

1) hang the system running state information of base station under BMU real-time collecting, once detect exception, abnormal information is recorded to file and abnormal data is uploaded to EMS, operation maintenance personnel can at the scene or remote detection abnormal information diagnosing.EMS is by alarm relevant for basis and abnormal reporting information diagnostic system mistake.

2) in order to Suppression network alarm windstorm, the filter (being arranged between EMS and BMU) by EMS arranges alarm shield option, stores, the shielding of non-emergent warning information just only have great alert options to notify EMS in BMU side; According to the demand of fault location, ask the BMU of appointed area in stipulated time reporting fault information at EMS side wheel, reduce load and the disposal ability requirement of EMS server to greatest extent.

Certificate server (Radius Server), for realizing the location management function for Pico BS, ensures legal Pico BS access network.

Consider fail safe, between network management center (EMS and NMC) and BMU, take IPSEC (Internet Protocol Security, the Internet protocol security) mode to carry network management information, in network management center to public network direction configuring firewalls.

The network method that the present invention proposes, can be good at realizing multi-zone supervision function, Suppression network storm, realizes distributed webmaster capacity extension scheme.

Figure 13 shows that the charging policy schematic diagram of wireless access system of the present invention.Based on the access point supervising the network framework of layering, at CSN side definable charging policy flexibly, wherein charging policy can comprise the charging policy based on user, the charging policy based on base station and the charging policy etc. based on BMU.Charging policy based on base station and the charging policy based on BMU are applicable to enterprise network application scenarios.According to operation scene and the management tactics of operator, different charging measures is defined at BMU and AAA (certification, authentication and accounting server), AGW-Lite module in BMU inside produces charge information, comprises user profile, the base station at user place and detailed telephone expenses list.Data message, temporal information, quality of service information and idle mode information etc. can be comprised in telephone expenses list.

Figure 14 is the flow chart that the automatic frequency of the Pico BS of the embodiment of the present invention distributes.Distribute with traditional Wifi automatic frequency, the main distinction conveniently can realize main BMU assist lower automation configuration and manage.

In base station side, the legal frequency resource list needing acquisition backstage EMS server to forward through BMU, correct parallel compensate work can be carried out, specifically comprise following steps:

Step 1201, when Pico BS system starts, first carries out power-on self-test and the normal boot process of minimum system; Wherein, minimum system does not comprise the transmitter section of base station, adopts irrational frequency to produce interference to other base stations when mainly preventing from powering on;

Step 1202, after minimum system normally works, base station system is initiated to the handshake authentication flow process of BMU, applies for legal frequency resource;

Step 1203, BMU assists side the frequency resource selection realizing each node of BMU subordinate, mainly selects according to the neighbouring relations between each base station, provides the Candidate Frequency of recommendation for base station reference;

BMU assists side the parallel compensate realizing base station, can consider following pooled applications scene: (1) is initial stage networking, takes the networking of PUSC Segment mode; (2) be the network capacity extension, increase base station number, how the base station newly increased and existing base station carry out redistributing of frequency resource; (3) be base station dilatation, from the upgrading of PUSC Segment to PUSC All subchannel mode; (4) exception of base station restarts flow process.

After first three kind scene needs and EMS have coordinated frequency to configure, be synchronized to BMU side, so that corresponding automatic processing policy is selected in BMU side.The processing policy of the 4th kind of scenario B MU employing is: the history frequency point information of preserving this base station is fed back to base station.

With the Neighborlist (BS that gives a definition _i) be the Neighboring Cell List of base station i; Freq (BS _i) be base station BS _ifreq/Seg (frequency and segmentation) configuration information; Freq (BMU) is the alternative all Freq/Seg resources of BMU.

The processing policy of scene (1) is: for BS during initial stage networking _n, first BMU obtains each base station BS _nneighborhood region correlation chart Neighborlist (BS _n); Choose the simplest base station BS of neighboring BS relationship _i, the base station of physical location opposite edges often, program Stochastic choice Freq/Seg (BS _i); Frequency assignment routine automatically performs, and determines Freq/Seg (the BS ∈ Neighborlist (BS of base station in this base station Neighboring Cell List _i)), principle is that adjacent base station adopts different frequency Freq/Seg; Iterative program performs until complete frequency and the segment information distribution of all base stations.

The processing policy of scene (2) is: for newly increasing base station BS _n, BMU is according to newly increasing base station BS _nneighborhood region correlation chart Neighborlist (BS _n), obtain BS _nadjacent area frequency point information Freq (Neighborlist (BS _n)); From Freq (BMU) ∩ Freq (Neighborlist (BS _n)) supplementary set Stochastic choice frequency send to BS _n.Namely the frequency point allocation that selection one is different from this adjacent area, base station frequency from BMU alternative all Freq/Seg gives this base station.

The processing policy of the processing policy of scene (3) same to scene (1) substantially, unique difference needs the frequency information distributed to change to frequency from the frequency of scene (1) and segmentation: for BS during initial stage networking _n, first BMU obtains each base station BS _nneighborhood region correlation chart Neighborlist (BS _n); Choose the simplest base station BS of neighboring BS relationship _i, the base station of physical location opposite edges often, program Stochastic choice Freq (BS _i); Frequency assignment routine automatically performs, and determines Freq (the BS ∈ Neighborlist (BS of base station in this base station Neighboring Cell List _i)), principle is for adjacent base station distributes different frequencies; Iterative program performs until the frequency information completing all base stations distributes.

Consider that part operator may not have a lot of frequency resources, the present invention is when arranging Neighboring Cell List, although although consider in planning physically adjacent between base station, adjacent area isolation is better, also thinks it is not adjacent area in logic when configuring.

Step 1204, starts RSSI (Received Signal Strength Indication, the received signal strength indicator) input that receiver carries out this frequency, performs step 1205;

Step 1205, if the interference signal of this frequency is less than predetermined threshold value, then illustrates that this frequency can be used, and performs step 1206; If find serious interference in interferer signal detection flow process, namely the interference signal of this frequency is greater than or is more than or equal to a predetermined threshold value, then enter frequency-selecting flow process again 1203;

Step 1206, system carries out normal workflow, opens the transceiver circuitry of base station,

Step 1207, starts the process carrying out down link and up link according to the wireless parameter configuration of webmaster, terminates.

The automatic allocation flow of said frequencies, the enable or inefficacy by network management interface, to adapt to the network environment of differing complexity.

Comprehensive description above, the present invention proposes a kind of layer architecture and concrete solution in the wireless access system based on in-door covering, has following technique effect:

1) interface and form of medium flexibly between Pico BS access point and BMU, be beneficial to project plan and quick networking;

2) support the network management framework of layering, substantially increase expandability and the network performance of system, be beneficial to witched-capacity network construction.The Delamination Transmission of network management information, and the local routing of BMU inside of base station information, most of flow control is inner at localized network, saves webmaster and transmission bandwidth;

3) BMU installs near Pico BS, Signalling exchange completes in local area network (LAN), and the medium surface interactive performance between BMU subordinate base station improves greatly, comprises turn-on time, time delay reduces, shake minimizing and handoff and deadline reduces, and promotes user satisfaction;

4) gps clock of BMU configuration is shared in base station, support that timing information is by twisted-pair feeder, cable, optical fiber or even power line transmission, in the recovery of base station completion timing information, configure GPS module without the need to each base station and fix up an aerial wire, reduce and lay inside plant resource and the engineering difficulty fixed up an aerial wire and cost, reduce CAPEX (capital expenditures) and the OPEX (profit approach) of operator.

5) due to uncertain characteristic that the interference signal of powerline systems is introduced, the present invention supports the quality recovered according to Link State and timing signal, realize the self-adapting intelligent scheduling mechanism of system, the work of safeguards system stalwartness, greatly improve the adaptive capacity to environment of system, elevator system availability.

6) upgrading from the whole groups of subchannels net mode of PUSC Segment to PUSC is supported;

7) Pico BS is at subrange by the combination of DAS (distributing antenna system) system, and antenna, can well improved system covering performance, simultaneously the ratio increase of high order modulation near subscriber unit, the average throughput of elevator system.

industrial applicibility

The present invention can answer land used wireless access system, solves indoor deployment difficulty, contradiction between quantities and maintenance management well, in centrostigma distribution gps clock packets of information to base station, achieves the indirect synchronization between base station.For the network quality of power line transmission, proposing the dynamic dispatching mechanism based on recovering timing quality, in the higher situation of timing accuracy, providing higher capacity of eating dishes without rice or wine, by reducing the reliability service of power system capacity safeguards system in timing accuracy reduction situation.

Claims

1. the frequency allocation method in layered radio access system, described layered radio access system comprises and is positioned at the access point administrative unit of Access Layer and the access point of lower extension thereof, and this frequency allocation method comprises:

2. frequency allocation method as claimed in claim 1, is characterized in that:

When described access point starts, first carry out the power-on self-test of minimum system and normal startup, be then initiated to the handshake authentication flow process of described access point administrative unit, apply for legal frequency resource; After receiving candidate's frequency that affiliated access point administrative unit issues, open receiver and carry out received signal strength indicator and RSSI input, if the interference signal of described candidate's frequency is less than or is less than or equal to predetermined threshold value, then judge that detection is passed through, otherwise, judge to detect and do not pass through.

3. frequency allocation method as claimed in claim 1 or 2, is characterized in that:

Described access point administrative unit is when taking part to use subchannel segmentation and PUSC Segment mode networking, in the following ways for access point selects candidate's frequency and segmentation: the Neighboring Cell List first obtaining each access point, choose the simplest access point of neighboring BS relationship, for its Stochastic choice frequency and segmentation, then be the access point selection frequency in its Neighboring Cell List and segmentation, must ensure as neighboring access point distributes different frequencies and segmentation, be followed successively by each access point in a manner described and select candidate's frequency and segmentation.

4. frequency allocation method as claimed in claim 1 or 2, is characterized in that:

5. frequency allocation method as claimed in claim 1 or 2, is characterized in that:

Described access point administrative unit is when taking part to use the whole subchannel of subchannel and PUSC All subchannel mode networking, in the following ways for access point selects candidate's frequency: the Neighboring Cell List first obtaining each access point, choose the simplest access point of neighboring BS relationship, for its Stochastic choice frequency, then be the access point selection frequency in its Neighboring Cell List, must ensure as neighboring access point distributes different frequencies, be followed successively by each access point in a manner described and select candidate's frequency.

6. frequency allocation method as claimed in claim 1 or 2, is characterized in that:

Described access point administrative unit preserves lower frequency point information of hanging access point, under mount and occur abnormal and after restarting, the history frequency point information of this access point preserved is fed back to this access point.