Abstract: A node (101) using a contention-based access scheme will monitor a channel for a predetermined condition. If the predetermined condition is detected, the node will defect from the contention-based access scheme, where any generated messages will be immediately transmitted. Should a second condition be met, the node will again follow the contention-based access scheme.

Abstract: When a candidate node (104) wishes to join a network (100), network access is either allowed or denied based on the candidate node's physical location. More particularly, a plurality of nodes associated with the network aide in locating the candidate node. Once located, a decision is made to either allow or deny network access based on the candidate node's physical location.

Abstract: A method (500) and system for compensation of frequency offset between a first transceiver (102) and a second transceiver (104) in wireless communication are disclosed. The compensation of the frequency offset between two or more transceivers (102, 104) is achieved by transmitting a set of frequency synchronization bursts. These bursts contain information about the frequency offset. The frequency synchronization bursts are transmitted by the first transceiver at a range of frequencies above and below its carrier frequency (502). When system conditions permit, a subset of the set of frequency synchronization bursts may be transmitted instead of transmitting the full set of frequency synchronization bursts.

Abstract: The invention is a routing method for data in a personal area network. The personal area network includes a plurality of nodes. The method includes receiving a frame at a node, determining whether the node contains a routing table entry for the frame destination, and when the node contains a routing table entry, determining a route for the frame based on a first routing protocol. The method further includes, when the node does not contain a routing table entry for the frame destination, determining whether a route should be discovered for the frame destination, and when a route should not be discovered, determining a route for the frame based on a second routing protocol.

Abstract: A direct sequence spread spectrum (DSSS) receiver (100) consistent with certain embodiments has a frequency generator (112) that generates a local oscillator signal without use of a piezoelectric crystal. A frequency converter (108) receives the local oscillator signal and mixes the local oscillator signal with a received DSSS signal to produce a down-converted signal. The received DSSS signal is encoded using a first set of DSSS code. A differential chip detector (116) receives the down-converted signal and converts the down-converted signal to a differentially detected signal. A correlator (120) receives the differentially detected signal and correlates the detected signal with a set of DSSS codes that are time-shifted from the first set of DSSS codes. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.

Abstract: An “identical beacons” field (401) is inserted near the beginning of a transmitted beacon (403) that contains either an integer equal to the number of consecutive identical beacons sent (i.e., identical to the one presently being transmitted) or a repetition bit indicating whether or not the beacon contains changed information when compared to a prior-sent beacon. After sleeping awhile, a node (302-304) wakes up, receives a first portion of the beacon containing the identical beacons field, and analyzes the identical beacons field. Based on the analysis, the node makes a decision on whether to remain “awake” for reception of the remaining beacon or to return to sleep.

Abstract: The present invention provides a multimode receiver design for mitigation of frequency offset by selective demodulation of an input modulated signal. The receiver (103) comprises a plurality of demodulators (207). Each of the plurality of demodulators (207) has the same functionality but different receiver sensitivity versus frequency-offset mitigation characteristics. Each of these demodulators incorporates a different demodulation technique. A suitable demodulator is selected to demodulate the received signal. The choice of a suitable demodulator is based on the value of the frequency offset (305, 307).

Abstract: A method (500) and system for compensation of frequency offset between a first transceiver (102) and a second transceiver (104) in wireless communication are disclosed. The compensation of the frequency offset between two or more transceivers (102, 104) is achieved using frequency synchronization bursts. These bursts contain information about the frequency offset. The frequency synchronization bursts are transmitted by the first transceiver at a range of frequencies above and below its carrier frequency (502). A second transceiver that receives at least one of these bursts (504) determines the frequency offset (504), and adjusts its frequency to match the frequency of the first transceiver (508). Thereafter, the second transceiver may enter a low power sleep mode (510) in order to reduce its power consumption. The second transceiver returns to active mode (512) just before the start of the transmission of the data packets (514).