195 results about "Vertical handover" patented technology

A service advisor detects the availability of a wireless communication service, communication being consistent with one or more protocols (e.g., IEEE 802.11 MAC layer) each having a plurality of packet formats. The service advisor includes an interface, a receiver, and an engine. The interface couples the service advisor to a provided consumer electronics product-(e.g., a cell phone or personal digital assistant (PDA)) having an annunciator (e.g., a display, speaker, or vibrator). The receiver receives communication by scanning a plurality of channels. The engine, coupled to the receiver and to the product via the interface, recognizes in response to the communication, only a limited set of packet formats of the plurality of formats; determines, from a packet having a format of the set, indicia of an available service; and facilitates operation of the annunciator in accordance with the indicia of available service. Use of the available service by the product involves recognizing a packet format not included in the set. In one implementation, the provided product includes a transmitter for use of the available service. Power consumption by the product may be reduced when desired communication services are not available. Another service advisor discovers services for purposes of horizontal and vertical handover.

A coding approach for a robust and flexible network communication protocol is described. By using coding, it is possible to eliminate the need to track packet identities, and hence, it is possible to reduce coordination overhead associated with many conventional protocols. The method and system described herein takes advantage of multiple paths, interfaces, mediums, servers, and storage locations available in a network. The proposed protocol allows quick response to congestion by load balancing over different network resources. The method also enables soft vertical hand-overs across heterogeneous networks. In one embodiment, a media file is divided into chunks and transmitted using a transport protocol tailored to meet delay requirements of media streaming applications. Also described are different coding strategies for chunk delivery based upon an urgency level of each chunk.

An apparatus and method for implementing a vertical handoff between a WLAN and a broadband wireless communication network are provided. The vertical handoff apparatus includes a base station (BS) of the broadband wireless network and at least one access point (AP) of the WLAN within the cell coverage area of the BS, and a switch for forwarding packets between the BS and the at least one AP and processing a handoff between the BS and the at least one AP.

A vertical handover method in a heterogeneous overlay network communication system is provided. A vertical handover method for an overlay communication system including a plurality of base stations each serving at least one communication network technology to a mobile terminal includes determining whether a mobile terminal is located in a measurement region with reference to a vertical handover map in relation to a serving base station; detecting reachable base stations by activating all network interfaces when the mobile terminal locates in a measurement region; selecting one of the reachable base stations as a handover target base station; determining if the mobile terminal is located in a handover region with reference to the vertical handover map; and performing a handover if the mobile terminal is located in a handover region.

The present invention provides a method for wireless telecommunication using a wireless telecommunications network that includes a mobile unit and first and second wireless connection points. The first and second wireless connection points are communicatively coupled. The method includes forming a first wireless communication link between the mobile unit and the first wireless connection point and forming, concurrently with the first wireless communication link, a second wireless communication link between the mobile unit and the second wireless connection point. The method also includes selecting at least one of the first and second wireless communication links.

The present invention relates to a vertical handoff method. According to the present invention, a serving network of a mobile station is determined. Herein, the mobile station that can access a first network having relatively wide service coverage and a second network having relatively narrow service coverage in an area where service coverages of heterogeneous networks are overlapped. When accessing the serving network of the first network, it is determined whether a received signal strength received from the second network is greater than a first threshold value. In addition, a first vertical handoff is decided by using a result of prediction of a transition pattern of the received signal strength that is greater than the first threshold value. When the serving network is the second network, it is determined whether the received signal strength received from the second network is less than a second threshold value. By using a result of prediction of a transition pattern of the received signal strength that is less than the second threshold value, a second vertical handoff is decided. Herein, the first threshold value is greater than the second threshold value.

A method and system for terminal switching in a wireless communication system are disclosed. A terminal accesses a packet data network through a packet data network gateway, when the terminal switches between gateways, the target gateway to which the terminal switches allocates a new Routing Identifier (RID) to the terminal, and stores a mapping relationship between the Access Identifier (AID) and the new RID of the terminal. The target gateway or the target mobility management entity (MME) of the terminal initiates a registration update request including the new RID of the terminal to the home Identity Location Register (ILR) of the terminal. After receiving the request, the home ILR of the terminal updates the stored AID-RID mapping information of the terminal according to the new RID of the terminal, and initiates a notification for updating the RID of the terminal to the opposite gateway and/or the opposite MME.

To improve network coverage or reduce false handover triggering, at least one client terminal is set to operate as a virtual access point (VAP) in a first wireless network by an AP controller. If a mobile device detects that a signal quality estimate of communications via an AP of the first wireless network is below a first value, the mobile device performs a handover procedure to the VAP. While maintaining the call via the VAP, if the mobile device detects that the signal quality estimate is back above the first value, the mobile device performs a handover procedure back to the AP of the first wireless network. On the other hand, if the mobile device detects that the signal quality estimate is below a second value which is less than the first value, the mobile device performs a vertical handover procedure from the VAP to a base station of a second wireless network.

An inter-network packet transmission method and system in a vertical handover between the two different technology networks is provided. An inter-network packet transmission method includes tunneling between gateways of heterogeneous networks though an interface, updating a routing table of at least one of the gateways by exchanging information through the interface, and transmitting packets to a user equipment based the at least one updated routing table.

In this invention, a novel vertical handover control algorithm, consisting of a throughput-based mapping function, QoS-based dynamic handover thresholds, and performance-based trigger timers, are proposed to resolve uncommon pilot problem, QoS requirements, and ping-pong effects, respectively. An analytic model based on a finite state machine is developed to evaluate the proposed algorithm in terms of the handover frequency and achievable throughput. A numerical analysis is also provided to further quantify the performance impacts.

The invention discloses a heterogeneous network vertical handover method based on network joint effect optimization and load balancing and belongs to the technical field of wireless communication. According to the invention, load balancing and network joint effect maximization between access networks are realized through optimized vertical handover and access network selection of users of a commonly covered area of heterogeneous access networks. A user information matrix is established, a network joint effect function is modeled, and under the conditions of giving access network load balancing, joint network user handover times and the like, optimized user vertical handover and network election schemes are obtained through maximizing the network joint effect.According to the heterogeneous integration realizing network, user vertical handover and network selection schemes of access network load, user handover times, user business characteristics and other factors are comprehensively considered, the maximization of network comprehensive benefits and the enhancement of quality of service (QoS) for users are realized.

In the invention, a mobile relay station is added into the system; the radio self-networking mode is set in the dual-mode mobile terminal; as required, the dual-mode mobile terminal is switched into the radio self-networking mode from cellular network access mode or wideband radio access mode; under the radio self-networking mode, the dual-mode mobile terminal accesses the base station of mobile wideband radio access network or the base station of cellular network; the mobile relay station is used in relaying information between the dual-mode mobile terminal and the base station of wideband radio access network or the base station of cellular network, under the self-networking mode.

The invention discloses a self-adaptation vertical handover method based on an RSS (Really Simple Syndication) variation trend, belonging to the technical field of wireless networks. The self-adaptation vertical handover method comprises the following steps: setting a handover execution threshold value for each candidate network by setting a handover trigger threshold value for a current service network; then measuring the strength value of received signals of the current service network and all the candidate networks and a round-trip time delay value of the current service network, and generating a signal strength sequence and a time delay sequence through normalization processing; and then, respectively averaging the signal strength sequence and the time delay sequence, then updating network evaluation values of all networks, and optimizing the handover triggering threshold values and the handover execution threshold values to realize the self-adaptation vertical handover. In the method, a linear weighting method is used for evaluating a heterogeneous network, meanwhile, a handover judgment threshold value is regulated in a self-adaptation manner according to the variation trendof the strength of the received signals, and thus, rapid and accurate vertical handover is realized.

A method, system, and business model are disclosed for supporting handover between a mobile host and a corresponding node located in a heterogeneous network. Handover paths are established to accommodate a plurality of quality of service properties. Admission control is performed that considers the established handover paths and an established first reservation path. Gateways are contacted to determine a handover path to use. The determined handover path is used to support vertical handover. A second reservation path is established while maintaining the first reservation path and the handover path.

The invention relates to a multi-mode terminal vertical switching method in a heterogeneous network, and belongs to the technical field of communication. According to the method, a network resource monitoring module, a network selection module, a switching judging module and a switching execution module are used; the network resource monitoring module monitors and collects candidate network resource information in real time, and provides data sources for the network selection module and the switching judging module; in the network switching stage, the network resource monitoring module mainly detects the service access and the network state; the switching judging module is mainly used for switching application judgment, performing priority ranking on switching applications according to the current network state and service condition information provided by the network monitoring module, and performing switching judgment according to the priority; after the switching judgment, the operation enters the switching execution module to perform switching execution. The multi-mode terminal vertical switching method has the advantages that in the vertical switching process, the priority of different service switching applications is fully considered; the switching execution is performed according to the priority; the service quality of different services is guaranteed.

The invention relates to a group vertical handoff method in heterogeneous wireless environment, comprising the following steps: terminal side equipment collects various upper layer information and bottom layer information of an access network which the terminal side equipment belongs to, calculates to obtain included angle and distance of user target vector and network capacity vector; whether preset threshold value conditions are met is judged, if not, handover requests are sent to an access device; the access device forwards the handover requests to a decision-making server; the decision-making server, based on loading conditions and service conditions of each access network, processes the handover requests in a collective way and returns obtained handover decision-making results to corresponding terminal side equipment through access devices of the access networks; the terminal side equipment executes handover operation according to the handover decision-making results. The invention also relates to a vertical handoff system in a heterogeneous wireless environment. Proceeding from the whole system, the invention makes full of network heterogeneity to improve overall performance of the system and effectively improves resources utilization rate of the system.

An interworking network system between heterogeneous networks and a vertical hand-off method for supporting QoS are provided. WLAN (Wireless Local Area Network) and Wibro (Wireless Broadband) have a service range overlaid with that of the CDMA (Code Division Multiple Access) 2000 that has been provided over the whole area, and routers of the respective networks are hierarchically connected by setting the CDMA 2000 as a higher network, the WiBro as a middle network, and the WLAN as a lower network according to service area and transmission speed of the respective networks. Accordingly, a hierarchical interworking method has been provided as an integrating network of the CDMA 2000, WiBro, and WLAN independently providing a service so that it may minimize packet loss and delay.