CN101263685A

CN101263685A - Radio communication terminal and network side communication apparatus

Info

Publication number: CN101263685A
Application number: CNA2006800330819A
Authority: CN
Inventors: 平野纯; 高添明; 吴振华; 陈必耀; 荒牧隆
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2005-09-09
Filing date: 2006-09-08
Publication date: 2008-09-10

Abstract

A technology is disclosed for achieving fast and reliable handover. According to this technology, in the network composition where a network coverage area of the cellular base station 105 and network coverage areas of plural WLAN AP (Wireless LAN access point) 110, 115, 120 and 130 overlaps, the roaming mobile node (mobile terminal) 100 stores the listened beacon information from each WLAN AP. The mobile node can promptly perform the handover procedures without waiting for listening to the next beacon by acquiring the beacon information of WLAN AP which is a handover target from the stored information at the instant of determining to do handover to a new WLAN AP. Furthermore, the mobile node can store information on stability of the network connection if it would be connected to each WLAN AP, and determine which WLAN AP is suitable for a handover target by considering the stability.

Description

Wireless communication terminal and network side communication apparatus

Technical field

The present invention relates to wireless communication terminal (being also referred to as portable terminal or mobile node) and network side communication apparatus about the communication in packet switched data communication networks.More specifically, its wireless communication terminal and network side communication apparatus about having dissimilar a plurality of access interfaces.

Background technology

Be currently included in the mobile computing that is linked into the internet in moving and become more general.Cell-phone constantly increases in the use of functional and WLAN, and the internet constantly increases.Current, increasing portable terminal device has the ability of using access technology widely and being connected to the internet, and described access technology is the third generation (3G) Cellular Networks, GPRS (GPRS), IEEE 802.11a/b/g and bluetooth for example.Mobility refers to: even when node motion, network connects also available.

Have and strengthen various portable computings network capabilities, for example hand held mobile phone, kneetop computer and PDA(Personal Digital Assistant) and increased requirement for seamless communication in wired and wireless network.For example the use of the increase of the content of multimedia of video conference makes seamless communication become essence in move connecting and required feature.Actual mobile management should provide seamless handoff, and wherein the user can not observe communication disruption.Current mobile data network is made up of the network of supporting different data transfer rates and the geographical some no line overlaps that cover usually, and only can insert via the specific air interface of medium.

When mobile node changes sub-district, subnet or network, must between each serving access node, switch covering responsiveness (responsibility).In order to be provided at the seamless roam in these heterogeneous networks, mobile node must can be connected to various access networks.In addition, agreed mutually comprehensively global mobile communication network configuration need be managed huge amount of movement.Simultaneously, by available wireless access technology widely, the portable data assistance (multimode node) with multiple access interface begins to occur.These comprise single/double mode hand-hold phone, kneetop computer and personal digital assistant.

In various files, described constantly or even use different access technologies to be connected to the serviceability of internet simultaneously in difference.But the agreement that embeds in the available multimode node in current consumer market is not provided at the seamless switching between the disparate interface.Also there are some problems that when seamless switching between disparate interface, will be solved.Because the diversity of overlapping available wireless network is considered from the angle of mobile node, the network availability of being considered can be temporary transient or stable.

For example, when mobile node during along the roaming of the edge of wireless network, even do not guarantee the stability of actual use, the temporary transient character of the network coverage also can cause falseness between network and Media Interface Connector and unnecessary handover.The expense that causes in such handover will be interrupted user's experience and the unnecessary load of cost on network.

A solution of following patent document 1 has proposed when portable terminal is roamed among this locality or the overlay area of global service at wireless network by triggering, has supported service to continue the scheme of (resumption).When keeping via different gateway, can continue global service with the getting in touch of same server.

Another solution of following patent document 2 is used the mobile switching centre in network, duplicated frame is sent to the roaming mobile terminal with synchronization timing, so that influence soft handover.Also handle and remove the duplicated frame that sends from terminal by mobile switching centre.

In addition, the honeycomb timing receiver that another solution of following patent document 3 has proposed to install in Wireless LAN access point is so that cellular network and WLAN by synchronously, make and can carry out soft handover.

[patent document 1] U.S.Patent Publication 20030112789A1

[patent document 2] U.S.Patent Publication 20040213279A1

[patent document 3] U.S.Patent Publication 20030030101A1

But, above-mentioned in patent document 1 disclosed solution do not optimize handover and handle and suffer previously described edge roaming problem.But, above-mentioned in patent document 2 disclosed solution can not cross over heterogeneous network work, if particularly network belongs to different range of management or service provider.But, above-mentioned in patent document 3 disclosed solution will require the honeycomb that participates in and wireless lan network by synchronously, thereby reduced total user capacity.In addition, as above-mentioned in patent document 2 situation of disclosed solution, cross over when different range of managements realizes this solution and also may have problems.

Can the above prior art of following summary.

Portable terminal can not keep seamless connectivity, particularly when crossing over heterogeneous network execution handover.

Portable terminal is difficult to determine that access network is for temporary transient still stable, so that carry out effective handover of whole network.

The edge roaming problem of unnecessary handover appears causing, particularly when mobile node when the edge of the network coverage is roamed.

Summary of the invention

Therefore, the purpose of this invention is to provide: wireless communication terminal, that its fast interface that can obtain to be used for seamless delivering switches and ,/or carry out effective handover and do not have unnecessary handover, and the stability that can improve the communication (particularly, link connects) of wireless communication terminal; And network side communication apparatus.

In order to obtain purpose of the present invention, the present invention provide a kind of wireless communication terminal to comprise:

A plurality of wireless communication interface parts, each of a plurality of wireless communication interface parts can be connected to one or more base stations,

Beacon (beacon) information stores parts are used for storing the information that is included in beacon signal, and wherein, periodically send from described base station and receive described beacon signal by each of described a plurality of wireless communication interface parts,

The beacon message searching part is used for being included in from the retrieval of described beacon message memory unit the information of beacon signal, according to predetermined trigger, and by receiving described beacon signal with the corresponding wireless communication interface parts of described predetermined trigger, and

Communication control unit is used for using the information that is included in beacon signal to control beginning and communicates by letter on described wireless communication interface parts, wherein retrieves described beacon signal by described beacon message searching part.

According to this structure, may obtain to be used for the fast interface switching of seamless delivering.

In addition, except above-mentioned structure, wireless communication terminal also comprises communication switching controls parts, be used for when on any one of described a plurality of wireless communication interface parts, beginning to communicate by letter or when on any one of described a plurality of wireless communication interface parts, switching attachment point, predetermined trigger is provided to described beacon message searching part, wherein said predetermined trigger with begin to communicate by letter or to switch the wireless communication interface parts of the base station that will connect corresponding.

In a single day according to this structure,, may obtain the fast interface switching by retrieving previous institute canned data in case begin communication or carry out the handover processing via wireless communication interface.

In addition, except above-mentioned structure, wireless communication terminal of the present invention also comprises the information stores control assembly, be used for based on the beginning of communicating by letter on the described wireless communication interface regularly, on described wireless communication interface, be connected to the switching timing of base station and about any one of the strategy of electrical power, control monitoring about the beacon signal of described wireless communication interface, maybe will be included in information stores in the beacon signal in the beacon message memory unit.

According to this structure, may store the information in the beacon signal that is included in based on as the timetable of communication beginning or switching timing or the ability of storage and saving electrical power.

In addition, except above-mentioned structure, wireless communication terminal of the present invention also comprises:

Stability information stores parts, be used to store about with the information of the stability of base station communication, each of wherein said a plurality of wireless communication interface parts can be connected to described base station, and

Stability is determined parts, is used for based on the information about stability that is stored in described stable information stores parts, and determining whether can be with described base station selected candidate for being used to communicate by letter.

According to this structure, the fast interface that may obtain to be used for seamless delivering switches, and carries out effective handover and do not have unnecessary handover.

In addition, except above-mentioned structure, wireless communication terminal of the present invention also comprises the stability assessment parts, be used for based on each beacon signal that receives from the base station by described a plurality of wireless communication interface parts or based on information about the stability of between other wireless communication terminals and base station, communicating by letter, be evaluated at the stability of communicating by letter between each and the base station of described a plurality of wireless communication interface parts, wherein, notify described information from described other wireless communication terminals.

According to this structure, wireless communication terminal may based on the beacon signal that receives from the base station or with other wireless communication terminal exchange, about with the information of the stability of base station communication, assess stability with base station communication.

In addition,, in wireless communication terminal of the present invention, described stability assessment parts are arranged to except above-mentioned structure: based on the information relevant with the stability of communication or the frequency of detected beacon signals the time become pattern, come to be sorted in the base station.

According to this structure, the wireless communication terminal stability of communicating by letter with each base station that may sort.

The message transmit block is used for becoming the base station that is lower than predetermined threshold level to its stability and sending the message that request improves the stability of communication by with reference to the information about stability that is stored in described stable information stores parts.

According to this structure, may improve the stability of the communication of wireless communication terminal.

In addition, except above-mentioned structure, in wireless communication terminal of the present invention, described message comprise at least the base station identifying information, wireless communication terminal identifying information and about with the communication feature information of communicating by letter of base station.

According to this structure, can grasp communication feature between source and destination by Reference News.

In addition, except above-mentioned structure, wireless communication terminal of the present invention also comprises: the stability assessment parts, be used for based on each beacon signal that receives from the base station by described a plurality of wireless communication interface parts or based on information about the stability of between other wireless communication terminals and base station, communicating by letter, be evaluated at the stability of communicating by letter between each and the base station of described a plurality of wireless communication interface parts, wherein, notify described information from described other wireless communication terminals.

According to this structure, the wireless communication terminal stability with each base station communication that may sort.

In addition, in order to obtain purpose of the present invention, the invention provides a kind of wireless communication terminal and comprise:

Stability is determined parts, is used for based on the information about stability that is stored in described stable information stores parts, determines whether to begin between described wireless communication interface parts and base station communication.

According to this structure, may carry out effective handover and do not have unnecessary handover.

In addition, except above-mentioned structure, in wireless communication terminal of the present invention, described message comprise at least the base station identifying information, wireless communication terminal identifying information with about with the communication feature information of communicating by letter of base station.

In addition,, the invention provides a kind of network side communication apparatus that cooperates wireless communication terminal, comprising in order to obtain purpose of the present invention:

The wireless communication interface parts are used for communicating by letter with described wireless communication terminal,

Information receiving parts is used for via the wireless communication interface parts, from the message of wireless communication terminal reception request improvement with the stability of communicating by letter of wireless communication terminal, and

Communication stability improves parts, is used for operation by control wireless communication interface parts and improves the stability of communicating by letter with described wireless communication terminal, and wherein said wireless communication terminal is the source of described message.

According to this structure, may improve the stability of the communication between network side communication apparatus and wireless communication terminal.

In addition, except above-mentioned structure, in network side communication apparatus of the present invention, described communication stability is improved parts be arranged to:, increase transmitted power or adjusting directional characteristic towards described wireless communication terminal as the controlled operation of described wireless communication interface parts.

According to this structure, network side communication apparatus can be by increasing transmitted power or regulating directional characteristic and improve the stability of communicating by letter with wireless communication terminal.

The present invention who comprises said structure has the fast interface that obtains to be used for seamless delivering and switches and/or carry out effective handover but not the advantage of unwanted handover.The present invention also has the advantage of the stability of the communication (especially, link connects) that improves wireless communication terminal.

Description of drawings

Fig. 1 illustrates the figure of vertical view of network that in an embodiment of the present invention wherein mobile node is crossed over the overlapping region roaming of a plurality of network coverages;

Fig. 2 is the block diagram that the topology example of mobile node in an embodiment of the present invention is shown;

Fig. 3 is the state diagram that fast interface handover operation in an embodiment of the present invention is shown;

Fig. 4 is the state diagram that reliable interface handover operation in an embodiment of the present invention is shown;

Fig. 5 is the state diagram that quick and reliable interface handover operation in an embodiment of the present invention is shown;

Fig. 6 is the figure near the information element example notice (Proximity Notification) message that sends from mobile node that is included in that illustrates in an embodiment of the present invention;

Fig. 7 is the block diagram that the topology example of network node (potential attachment point) in an embodiment of the present invention is shown; And

Fig. 8 be illustrate in an embodiment of the present invention about state diagram near the operation example of notification message.

Embodiment

Provide description below with reference to accompanying drawing about embodiments of the invention.Fig. 1 has described the typical case that mobile node 100 is roamed in having the neighborhood of a plurality of overlapping regions of the network coverage of cellular basestation 105 and WLAN AP 110,115,120,125 and 130 for example.In description, cellular basestation only is called the base station.Mobile node 100 may adopt route 135, thus, its in remaining on its cellular network overlay area in, by the edge of overlapping wlan network overlay area.In order to obtain rapid and reliable handover, system can comprise some key features.

Switch for fast interface, system of the present invention should have some and be used for preserving even about the method in the broadcast message of current communication un-activation or the interface that comprises.Therefore as example, the WLAN interface can be by the beacon (beacon) of contiguous access point or any broadcasting of the passive monitoring of couple in router.The beacon message that storage is received.

According to the ability of device, the beacon message of storage can be placed in the tabulation or continuous information (up-to-date information) replacement by nearest reception.Therefore, the node with strict power and/or message storage requirement can only be stored the beacon message of up-to-date reception, can store the more beacon message of big figure and have those nodes of not being strict with.Under base band was in by the situation in the zone of two or more access points or router covering, the storage beacon message may be useful.

For the device of storage, may be useful according to source sign storage beacon more than a beacon message.Like this, only store from the nearest beacon message in each source and be not stored in the whole beacon messages of short beacon time period from single source.

For supporting that for example LINK_GOING_UP is (from the trigger of Media Interface Connector, it is available that it indicates new link to become) or LINK_GOING_DOWN (from the trigger of Media Interface Connector, it is unavailable that it indicates current link to become) lower level prompting or the node of incident, can further strengthen previously described method.The example of such low layer Media Interface Connector incident those examples that the medium independence handover function that defines in IEEE802.21 provides of can serving as reasons.Can will be tied in the monitoring of finishing on the total interface that current link lost efficacy (go down) or the reception of trigger warning when detecting potential new link, therefore preserve the limited power of mobile node.

When causing mobile node decision handoff links or interface when the link of current use is unavailable or owing to the specific policy decision, mobile node must select alternative interfaces or link to utilize.Except any other strategy was considered, this selection can be by the availability impact of previous described stored information.When successful option interface, come into operation immediately about any stored information of selected interface, and like this, the connectivity of mobile node can be by Fast Reconstruction.

Figure 2 illustrates the required functional structure of such system.Mobile node 100 comprises Media Interface Connector 200,205 and 210.Media Interface Connector 200,205 and 210 is a logic interfacing, and it can be regarded as, and node uses and the physical interface card of external network communication.For example, Media Interface Connector 200,205 and 210 comprises WLAN card, GSM card or even modulator-demodulator.

Media Interface Connector 200,205 and 210 also can be represented the link of different attachment point.For example, the blue tooth interface that is connected to the peer (peer) of two separation can be considered two corresponding Media Interface Connectors, and each peer uses one.Media Interface Connector 200,205 can be communicated by letter with 260 via corresponding message pathway 250,255 and is configured with 210 by management entity 215.

Management entity 215 is a master controller, the various types of network functions of its management node.In addition, management entity 215 should comprise Stability Control unit 220 and configuration control unit 225 at least.It also can comprise other function, for example determines and control those functions of the handover from an attachment point to another.Strategy controller 230 is via message pathway 265, will be provided to management entity 215 from its input information of strategy, forms with the decision that helps it.Replacedly, management entity 215 can be directed to related parameter, comes query strategy controller 230 via message pathway 280.

Management entity 215 also has to the access passage (access) of two logical data bases (stable information database 235 and configuration information database 240) at least.Management entity 215 can write or retrieving information from these databases respectively via

message pathway

270 and 275.

Stability information database 235 keep belonging to any near or the information of the stability of the current potential network attachment point that runs into.The example of canned data comprises that the type of the access technology that is used to connect, the identifier of attachment point, its detected signal strength signal intensity and bit error rate (BER) or certain describes the module of the stability of attachment point.

Media Interface Connector 200,205 and 210 can realize being used for the measuring ability of detection signal strength or bit error rate, and, based on the beacon signal that receives from the base station, the testing result of for example signal strength signal intensity or bit error rate can be stored as in order to indicate the module of stability.The base station that can be connected to Media Interface Connector 200,205 and 210 can send above module to mobile node, with the stability that in beacon signal, embeds of indication (for example, the information of the state of indication attachment point), and mobile node can be with information stores in its stable information database 235.In addition, if exchange module among mobile node, then each mobile node can obtain module each attachment point, that be used to indicate stability.Based on the module that is used in stable information database 235 indication stability, by the stability of mobile node 100 ordering (classification) each attachment point.In the case, for example, mobile node 100 stability of can classifying makes that the attachment point ordering with better communication quality is higher, or feasible consideration pattern or the trend attachment point that sorts.Above pattern refers to detect the time trend that is used to indicate stable module.About pattern, for example, if along with the stability of effluxion, attachment point increases gradually, then preferably, this attachment point ordering is higher.Above trend refers to be used to indicate the detection frequency of stable module.About trend, for example, if the frequency of the detection of the module of attachment point increases in the given time period, then preferably, this attachment point ordering is higher.

Configuration information database 240 keeps from any configuration information of all potential attachment point acquisitions.According to the memory space relation, this information can be for the order tabulation of each attachment point or only is the nearest information that receives.The example of each information can be the beacon message from the WLAN access point, it can comprise such information, as: following beacon interval, the data transfer rate of being supported, parameter setting and performance information or the higher layer information such as the router advertisement message that comprises prefix information (Router Advertisementmessage) and other Service Notification of on layer 2 link, carrying.Preferably, determine the information storage function of unit by being placed on medium access between network insertion unit (comprising PHY (physical layer), MAC (medium access control), LLC (logic link control) etc.) and the higher level (layer 3 and more than), realize stable information database 235 and configuration information database 240.

Reside in the classification of the stability of Stability Control unit 220 its peers of control in the management entity 215.Its handles the information received, and storage or from stable information database 235 retrievals they.It can be configured to the scope of receive threshold or parameter, so that classify potential attachment point.It also can be responsible for selecting to appear at node potential link or interface in front, selects next handoff target with stability metric standard and any threshold parameter based on them.

225 controls of configuration control unit are from the storage and the retrieval of the configuration information of any reception of Media Interface Connector 200,205 and 210.It also can be responsible for: in case finish the selection of handoff target, just the configuration information that will receive from handoff target recently is delivered to node.

State at Fig. 3 there is shown the operation that is used for the fast interface switching.In Fig. 3, mobile node 100 begins (step 300) with idle condition.Shown in step 305, according to its power policy, the information (step 310) about near potential attachment point can be collected and store to portable terminal on one's own initiative, or only just begin its monitoring and stores processor (step 320) when handover immediately.

When determining that (or indication) beginning handover is handled, call handover rapidly and handle (step 325).When mobile node has selected to be used for interface that handover arrives or link, will be delivered to mobile node (step 330) about the information (previous institute canned data) of selected interface or link, do not wait for the beacon of next broadcasting so that handle handover immediately.Mobile node is discerned finish (step 335) of any handover process that other needs, and will use normal operating process afterwards, returns initial condition (idle condition of step 300) then.If do not store information about selected interface or link (for example, determining that the beginning handover can not collect under the situation of the information that needs before handling), will get back to normal processes, will be delivered to mobile node from the information of the beacon collection of next broadcasting then.

When mobile node 100 during, consider that from the angle of mobile node 100 availability of network in essence may be for temporary transient along the roaming of overlapping network covers edge.In order to prevent to cause the selection of the temporary transient interface link of unwanted handover, the system that is used for based on network stability influence interface selection is desired.This system is used for according to the classify solid interface switched system of usable interface or link of the history of incident.

During the collection of above-mentioned information, mobile node 100 also should keep the recording of information about various interface that received.This record provides the history about the various possibility links of interface.These are different with previously described information-storing device, and this is because be not that the information that all obtains from any broadcasting that receives all needs to be stored.This record keeps following the tracks of the various resources of broadcast message, and attempts link is categorized as stable and temporary transient classification.

Can come more new record by handling broadcasting, prompting, incident, trigger that is received or any out of Memory that obtains in addition about near the potential attachment point mobile node 100.For example, if the constant period of the beacon that is received then can be supposed to provide with the beacon of intermittent another access point that receives only from its access point that sends beacon and compare metastable the connection.

When node is being chosen the replaceable attachment point of network, can not report that the potential attachment point with temporary transient or unsettled record is so that consider (being thought of as the candidate of handover target).Be used to determine whether to report that the certain threshold level of potential link is that medium is specific, and can or can not share that to be used for record sort be stable similar value.Example can be: use the average signal strength that receives beacon to determine whether to this link of node report.Another example of threshold value can be the percentage of the erroneous packet that is received.

State at Fig. 4 there is shown the operation that is used for reliable interface switching.Mobile node 100 begins (step 400) with idle condition.Shown in step 405, according to its power policy, the information about near potential attachment point can be collected and store to mobile node 100 on one's own initiative, and according to the stability link (step 410) of classifying, or only when handover (step 415) immediately, just begin its monitoring and stores processor and according to the stability link (step 420) of classifying.

When determining that (or indication) beginning handover is handled, call handover rapidly and handle (step 425).When mobile node is selected interface that handover arrives or link, reference is about the various possible attachment point information on total interface, and those that only will pass through any threshold are delivered to mobile node 100 so that be thought of as candidate's (step 430) of handover target.Mobile node 100 is selected one and is used for handover from the candidate who is received.Then, mobile node identifies finish (step 435) of any handover process that other needs, and is following afterwards and will use normal operating process, then, turns back to initial condition (idle condition of step 400).If (for example do not store as yet about the information of selected interface or link, before handling, definite beginning handover can not collect under the situation of the information that needs), to get back to normal processes, then, will be delivered to mobile node from the information of the beacon collection of next broadcasting.

State at Fig. 5 there is shown the operation that is used for reliable interface switching.Mobile node 100 begins (step 500) with idle condition.Shown in step 505, according to its power policy, the information about near potential attachment point can be collected and store to mobile node 100 on one's own initiative, and according to Stability Classification link (step 510), or only when handover (step 515) immediately, just begin its monitoring and stores processor and according to Stability Classification link (step 520).Note, about near the information processing of potential attachment point with via from they the information that broadcasting received be stored as the processing that separates, and can manage by different strategies.Therefore, mobile node 100 is process information all the time, and potential attachment point is categorized as different stable grades, and only in handover just storage of active information immediately the time.

When determining that (or indication) beginning handover is handled, call handover rapidly and handle (step 525).When mobile node is selected interface that handover arrives or link, with reference to about the various possible attachment point information on total interface, and only will pass through any threshold those be delivered to mobile node 100 (step 535) so that be thought of as candidate's (step 530) of handover target.Subsequently, mobile node 100 is selected one and is used for handover from the candidate who is received.Mobile node is discerned finish (step 540) of any handover process that other needs, and is following afterwards and will use normal operating process, returns initial condition (idle condition of step 500) then.If do not store information about selected interface or link (for example, determining that the beginning handover can not collect under the situation of the information that needs before handling), will get back to normal processes, then, will be delivered to mobile node from the information of the beacon collection of next broadcasting.

According to prior art, when mobile node 100 along the path 135 whens roaming, because it touches the network coverage of WLAN AP 110,115,120,125 and 130, so mobile node 100 will be continuously 105 be handed over to WLAN AP 110,115,120,125 and 130 from the base station.Because mobile node reconfigures self,, also cause dissatisfactory user's experience of continuous interruption so this has wasted Internet resources.

On the other hand, following step of the present invention, when mobile node 100 roamings, it at first begins to connect via base station 105.Interface detects near the WLAN AP 110 the A of position and 115 appearance in Fig. 1.But, because mobile node 100 causes these WLANAP 110 and 115 both signal strength signal intensities very low at the edge of their covering, so, 200 their appearance of record of Stability Control unit, but they are not presented to the candidate of mobile node 100 as handover.

When mobile node 100 repeats above-mentioned incident when WLAN AP 110,115,120 and 125 roams.Configuration control unit 225 will be stored any from these WLAN AP 110,115,120 and 125 broadcast messages (for example beacon) that receive, but Stability Control unit 220 is not delivered to the higher level in mobile node 100 with them so that be thought of as the candidate of handover.

When mobile node 100 roams into the covering of WLAN AP 130, the stability of the signal that Stability Control unit 220 identification is received, and, will be delivered to the information that WLAN AP 130 is considered as the handover candidate higher level in the mobile node 100.Suppose the strategy decision handover of mobile node 100, then dispose control unit 225 for example any broadcast message of the higher level configuration information that received of the previous beacon that receives and (if there is) be delivered to higher level.Then, mobile node 100 will dispose and himself utilize WLAN AP 130, and not wait for from next beacon or the information of WLAN AP 130 broadcasting.This allows to cause the handover of higher network efficiency and better network experience.

When mobile node 100 resided in the network's coverage area of this potential attachment point, mobile node 100 can send the Remote triggering device, is improved to the connection stability (reliability) of specific potential attachment point with request.By receiving this Remote triggering device, potential attachment point is by for example increasing electrical power or adjusting the directional characteristic of wireless signal, is improved to the connection stability as the mobile node 100 in the source of Remote triggering device.The improvement that mobile node 100 is discerned about the stability of received signal, and, the result, mobile node 100 will be connected to this potential attachment point probably.

Although receiving remote trigger, potential attachment point always must not be improved to the connection stability as the mobile node 100 in the source of Remote triggering device yet.Potential attachment point can be improved to the stability as all mobile nodes in the source of Remote triggering device.Potential attachment point can be improved to as the connection stability of the part of the mobile node in the source of Remote triggering device (for example, described mobile node satisfies some other requirements or selected at random), but ignores the Remote triggering device from other mobile node.

When mobile node 100 during along route shown in Figure 1 135 roaming, in case detect WLANAP110,115,120,125 and 130 (potential attachment point), mobile node 100 just takes to washability Remote triggering device (next is near notification message) is sent to the further action of selected potential attachment point.

In Fig. 6, illustrate in an embodiment of the present invention, be included in the example that sends from mobile node near the information element the notification message.Typically, send to potential attachment point with graphic among Fig. 6 near notification message by mobile node 100.Should be by receiving near notification message, potential attachment point can be carried out the operation about mobile node 100.

For example, by receiving near notification message, but but potential attachment point executable operations is so that stablize executable operations more to strengthen communication link so that set up communication link (promptly with mobile node 100 with the current communication link of mobile node 100, so that guiding mobile node 100 connects) if or set up communication link with this mobile node 100, the active operation of any needs then can be carried out.

For more accurate, when receiving this near notification message, potential attachment point can increase the intensity (electrical power that signal sends) of transmission information.In addition, potential attachment point can turn to interface mobile node 100, so that when the indication a little less than mobile node 100 receives the signal strength signal intensity that is received, regulate the directional characteristic of wireless signal.

Should be noted that when exchange between mobile node 100 and its potential attachment point when other data, control or management plane message (plane message), can create and separately or backpack ground send near notification message.

Comprise that near notice (Proximity Notification) message 4 fields are to insert information element (destination id field 601, source id field 602, messaging parameter field 603 and extra information field 604), as shown in Figure 6.

Destination id field 601 comprises describes this identifier near the target of notification message.The example of this identifier can be the APID of IEEE802 access point or the MAC ID of IEEE802 node.

Source id field 602 comprises this identifier near the node of notification message of transmission, and the example of this identifier can be and sending this MAC ID near the interface on the mobile node 100 of notification message.

Messaging parameter field 603 comprises the information of the description communications status of structure, as physical communication characteristic between destination and source node and logic communication characteristic.Mobile node 100 can send such information, as detected intensity or quality from the signal that potential attachment point received.In another was realized, messaging parameter field 603 also can be wrapped the messaging parameter of mobile node 100, for example electric current transmitted power and maximum the setting.

Extra information field 604 is the Optional Fields for potential attachment point, and it can comprise information, for example from the information relevant with checking, position or mobility of mobile node 100.

In order to send to potential attachment point near notification message, must strengthen the function of graphic mobile node 100 in Fig. 2 with above-mentioned.When management entity 215 receives potential attachment point when not satisfying the notice of stability criterion from Stability Control unit 220, according to the strategy that obtains via strategy controller 230, management entity 215 can send to potential attachment point with above-mentioned near notification message via relevant Media Interface Connector 200,205 and 210.

Be implemented in the function of describing among Fig. 7 in order to handle above-mentioned near notification message, potential attachment point (network node 700).Fig. 7 illustrates the block diagram of the topology example of network node (potential attachment point) in an embodiment of the present invention.

Network node 700 comprises one or more Media Interface Connectors 710.When receiving near notification message from mobile node 100, relevant Media Interface Connector 710 should carry out: should send to management entity 705 via message pathway 720 near notification message.

Management entity 705 retrieval is included near the information in the notification message, and, communicate information to strategy controller 715 to consult the suitable action that will carry out via message pathway 730 with strategy controller 715.The policy service that provides from strategy controller 715 is provided management entity 705.When the action determining based on this policy service to carry out, management entity 705 can send to relevant Media Interface Connector 710 via order path 725 with order, correspondingly taking appropriate steps, as be used to improve with the processing of the stability of the communication of mobile node 100 with make mobile node 100 be connected the initiatives of (beginning communication) rapidly.In concrete example, management entity 705 can be indicated near the determined Media Interface Connector 710 of notification message, to be increased in the stability of the signal that is received on mobile node 100 sides.

Management entity 705 is arranged in the network node 700 of Fig. 7, but management entity 705 can be positioned at the outside (physically being in the another location) of network node 700.For example, management entity 705 can be arranged in the couple in router of a plurality of access points of management.Similarly, strategy controller 715 can be positioned at the outside of network node 700.

When management entity 705 is positioned at network node 700 outside, can transmit policy service by use be used for communicating by letter to the message pathway 730 of network path alternate figures 7 of the management entity 705 that resides in the network node outside by TCP/IP (TCP).

Fig. 8 is the state diagram that illustrates in an embodiment of the present invention about near the operation example of notification message.In the state diagram of Fig. 8, described about having the summary of transmission near the additional work situation (behavior) of the mobile node 100 of the function of notification message.

In Fig. 8, the information about whole interfaces is always monitored, collected to mobile node 100, and classification link (based on the stability link of classifying) (step 800).In addition, whether mobile node 100 monitoring links stablize (step 810).When thinking that link is stablized, as change shown in 805 and 815 the loop, mobile node 100 is not carried out specific operation, and continues the monitoring link state.

But, (for example stablize if the discovery link is insufficient, be classified as stable link become be lower than specific grade (certain threshold level)), then the management entity 214 of mobile node 100 can determine, to send near notification message (step 820) to selected potential attachment point.To send to potential attachment point from mobile node 100 near notification message, then via conversion 825 return link monitored states once more.

In description, though illustrate and described the present invention with preferred embodiment to be considered to most realistic, but it should be appreciated by those skilled in the art that, can make the modification of various design detailss and parameter, the for example change in the design of the management entity among management entity 215, Fig. 7 715 or other construction package among Fig. 2, and do not deviate from scope of the present invention and boundary.

To in above-mentioned embodiment of the present invention, use each functional block to be embodied as LSI (large scale integrated circuit) as integrated circuit.Can respectively functional block be treated to the 1-chip, and part or all of functional block can be treated to the 1-chip, so that be included in the 1-chip.According to integration class, above LSI can be described as IC (integrated circuit), system LSI or super LSI.

In addition, the method that is treated to integrated circuit not only generates special circuit or general processor in addition for making LSI.Produce LSI, FPGA (field programmable gate array) for the processor that maybe can weigh able to programme for after resetting, can realize the connection or the configuration of circuit unit.

In addition, if because the establishment of development of semiconductor or another technology replaces another new integrated technology of LSI to occur, then functional block certainly can be integrated by using new technology.For example, biotechnology can be described new technology.

Industrial applicibility

The present invention have the fast interface that to be used for seamless delivering switch and/or carry out effective handover and Communication stability (especially, the link of the advantage of non-unwanted handover and improvement wireless communication terminal Connection) advantage. The present invention can be applicable to the communications field of packet switched data communication networks.

Claims

1. wireless communication terminal comprises:

The beacon message memory unit is used for storing the information that is included in beacon signal, and wherein, periodically send from described base station and receive described beacon signal by each of described a plurality of wireless communication interface parts,

2. wireless communication terminal as claimed in claim 1, comprise communication switching controls parts, be used for when on any one of described a plurality of wireless communication interface parts, beginning to communicate by letter or when on any one of described a plurality of wireless communication interface parts, switching attachment point, predetermined trigger is provided to described beacon message searching part, wherein said predetermined trigger with begin to communicate by letter or to switch the wireless communication interface parts of the base station that will connect corresponding.

3. wireless communication terminal as claimed in claim 1, comprise the information stores control assembly, be used for based on the beginning of communicating by letter on the described wireless communication interface regularly, on described wireless communication interface, be connected to the switching timing of base station and about any one of the strategy of electrical power, control monitoring about the beacon signal of described wireless communication interface, maybe will be included in information stores in the beacon signal in the beacon message memory unit.

4. wireless communication terminal as claimed in claim 1 comprises:

5. wireless communication terminal as claimed in claim 4, comprise the stability assessment parts, be used for based on each beacon signal that receives from the base station by described a plurality of wireless communication interface parts or based on information about the stability of between other wireless communication terminals and base station, communicating by letter, be evaluated at the stability of communicating by letter between each and the base station of described a plurality of wireless communication interface parts, wherein, notify described information from described other wireless communication terminals.

6. wireless communication terminal as claimed in claim 5 wherein, is arranged to described stability assessment parts: based on the information relevant with the stability of communication or the frequency of detected beacon signals the time become pattern, come to be sorted in the base station.

7. wireless communication terminal as claimed in claim 1 comprises:

8. wireless communication terminal as claimed in claim 7, wherein, described message comprise at least the base station identifying information, wireless communication terminal identifying information and about with the communication feature information of communicating by letter of base station.

9. wireless communication terminal as claimed in claim 7, comprise the stability assessment parts, be used for based on each beacon signal that receives from the base station by described a plurality of wireless communication interface parts or based on information about the stability of between other wireless communication terminals and base station, communicating by letter, be evaluated at the stability of communicating by letter between each and the base station of described a plurality of wireless communication interface parts, wherein, notify described information from described other wireless communication terminals.

10. wireless communication terminal as claimed in claim 9 wherein, is arranged to described stability assessment parts: based on the information relevant with the stability of communication or the frequency of detected beacon signals the time become pattern, come to be sorted in the base station.

11. a wireless communication terminal comprises:

12. wireless communication terminal as claimed in claim 11, comprise the stability assessment parts, be used for based on each beacon signal that receives from the base station by described a plurality of wireless communication interface parts or based on information about the stability of between other wireless communication terminals and base station, communicating by letter, be evaluated at the stability of communicating by letter between each and the base station of described a plurality of wireless communication interface parts, wherein, notify described information from described other wireless communication terminals.

13. wireless communication terminal as claimed in claim 12 wherein, is arranged to described stability assessment parts: based on the information relevant with the stability of communication or the frequency of detected beacon signals the time become pattern, come to be sorted in the base station.

14. a wireless communication terminal comprises:

15. wireless communication terminal as claimed in claim 14, wherein, described message comprise at least the base station identifying information, wireless communication terminal identifying information with about with the communication feature information of communicating by letter of base station.

16. a network side communication apparatus that is applicable to wireless communication terminal comprises:

17. network side communication apparatus as claimed in claim 16, wherein, described communication stability is improved parts to be arranged to: as the controlled operation of described wireless communication interface parts, increase transmitted power or the adjusting directional characteristic towards described wireless communication terminal.