Abstract:
PROBLEM TO BE SOLVED: To determine a restricted association indicator from a broadcast signal to determine an accessible access point and establish communication therewith.SOLUTION: A restricted association indicator is determined from a received broadcast signal, such as a beacon and a pilot signal (602), and an access point group identifier is obtained on the basis of the indicator (604). It is determined whether the group identifier is in a maintained list of accessible group identifiers (606). Communication is established with a related access point where the identifier is in the maintained list (608).
Abstract:
PROBLEM TO BE SOLVED: To reduce a number of handover-related failures that occur in a communication system.SOLUTION: Criteria for radio link failure detection and access terminal-controlled mobility take into account access point parameters related to neighboring cells that may be available as mobility targets. Filtering mechanisms for detecting radio link failure on the basis of radio layer problem reports also take into account the availability of various neighbor access points and their measured signal strengths. A handover command is sent earlier than in conventional systems and includes an indication that instructs the access terminal to delay handover until a specified condition is met. Handover may be delayed until the target access point becomes stronger than the source access point.
Abstract:
PROBLEM TO BE SOLVED: To provide a method for synchronizing a wireless communication system.SOLUTION: Silence duration for a base station is determined based on the time required for a neighbor base station to obtain or maintain synchronization. All transmissions from the base station are ceased for the silence duration. Levels of multiple base stations may cease transmissions at the same time, thus mitigating interference.
Abstract:
PROBLEM TO BE SOLVED: To facilitate applying offsets and/or selectable hysteresis values to favor access points in cell reselection.SOLUTION: In measuring and ranking surrounding access points in reselection, offsets are applied to favorable access points to facilitate cell reselection thereto. The offset can positively affect measurements, and thus ranking as well, in some cases. Negative offsets can also be applied to lower measurements of some access points. Hysteresis values can be applied in measuring current cells to prevent frequent reselection. The hysteresis values can be selected on the basis of a type of the current cell or related access point to expand the coverage area where desired.
Abstract:
PROBLEM TO BE SOLVED: To resolve confusion resulting from assigning the same identifier to multiple nodes.SOLUTION: A network may provide a time gap during which an access terminal may temporarily cease monitoring transmissions from a source node so that the access terminal may acquire a unique identifier from a target node. An access terminal may commence handover operations at a target node after determining whether the access terminal is allowed to access the target node. A source node may prepare several target nodes for potential handover in the event confusion is detected or likely. The source node may send information relating to the preparation of the potential target nodes to the access terminal, and thereby the access terminal initiates handover at that target node.
Abstract:
PROBLEM TO BE SOLVED: To provide a method for synchronizing base stations in a wireless communication system.SOLUTION: A silence duration for a base station is determined based on the time required for a neighbor base station to obtain or maintain synchronization. All transmissions from the base station are ceased for the silence duration. Multiple levels of base stations may cease transmissions at the same time, thus mitigating interference.
Abstract:
PROBLEM TO BE SOLVED: To provide a method and apparatus for secure data transmission in a mobile communication system.SOLUTION: There are provided a method and apparatus for secure transmissions. Each user is provided a registration key. A long-time updated broadcast key is encrypted using the registration key and provided periodically to a user. A short-time updated key is encrypted using the broadcast key and provided periodically to a user. Broadcasts are then encrypted using the short-time key, in which the user decrypts the broadcast message using the short-time key. One embodiment provides link layer content encryption. Another embodiment provides end-to-end encryption.
Abstract:
relatórios sobre falhas em rádio-enlace um nó de comunicação determina que uma falha de rádio-enlace ocorreu durante a mobilidade no estado de conexão de um terminal de acesso e relata a falha de rádio-enlace a outro nó de comunicação. por exemplo, um ponto de acesso-alvo pode determinar que a falha de rádio-enlace ocorreu durante o handover de um terminal de acesso e enviar uma mensagem de relatório sobre falha de rádio-enlace ao ponto de acesso que estava servindo anteriormente o terminal de acesso ou a algum outro nó (um nó de rede, por exemplo). no primeiro caso, o ponto de acesso servidor pode ajustar os parâmetros de mobilidade com base nestas informações sobre falha de rádio-enlace e, opcionalmente, outras informações sobre falha de rádio-enlace relatadas. no segundo caso, o outro nó pode enviar uma mensagem de relatório sobre falha de rádio-enlace ao ponto de acesso servidor, ou o outro nó pode ajustar os parâmetros de mobilidade com base nestas informações sobre falha de rádio-enlace (e, opcionalmente, outras informações sobre falha de rádio-enlace relatadas) e enviar os parâmetros de mobilidade ajustados ao ponto de acesso servidor.
Abstract:
sincronização de rede sem fio. sistemas e métodos que facilitam a sincronização de temporização entre nós sem fio em uma rede de comunicação sem fio são descritos. um nó sem fio de rastreamento pode sincronizar com um sinal do sistema de posicionamento global (gps), se disponível. alternativamente, o nó sem fio de rastreamento pode receber medidas de qualidade relacionadas a um ou mais nós alvo. as medidas de qualidade podem estar relacionadas a parâmetros que podem ser utilizados para avaliar o nó alvo quanto a sincronização de temporização. com base nas medidas de qualidade, o nó sem fio de rastreamento pode selecionar um nó sem fio alvo para sincronização de temporização. o nó sem fio de rastreamento pode subsequentemente sincronizar a temporização com o nó sem fio alvo. além disso, o no sem fio de rastreamento pode avaliar continuamente os nós sem fio vizinhos para detectar se outros nós sem fio possuem medidas de qualidade mais altas do que os nós sem fio alvo atuais, e podem então re-sincronizar adequadamente com nós possuindo medidas mais altas.