Patent ID: 8064363

Claim:
A node device ( 601 ) for a wireless sensor network, comprising: a receiver ( 651 ) for receiving transmissions from other nodes in said wireless sensor network, a controller ( 641 ) configured to selectively switch on said receiver ( 651 ) according to a timetable known to said controller ( 641 ), and a memory ( 642 ) configured to store information about other nodes in said wireless sensor network; wherein said node device ( 601 ) is configured to maintain synchronization with and receive beacon transmissions from another node in said wireless sensor network, said beacon transmissions conveying information related to controlling of network connections and data transfer between nodes, characterized in that said controller ( 641 ) is configured to read from received beacon transmissions information about neighboring nodes with which said node device ( 601 ) does not maintain synchronization, which information includes time information that describes timing of beacon transmissions from neighboring nodes in relation to the timing of beacon transmissions from the node with which the node device ( 601 ) received said beacon transmission, and to store such information into said memory ( 642 ), and said controller ( 641 ) is configured to utilize such stored information to selectively switch on said receiver ( 651 ) to attempt receiving a beacon transmission from such a neighboring node as a response to an observed failure in previously maintained synchronization.