Abstract:
PROBLEM TO BE SOLVED: To provide methods for reducing the amount of time required to complete a handoff in a system which uses different frequency bands.SOLUTION: A mobile station sends a handoff request to a current BS sector, which forwards the request to a new BS sector. The new BS sector processes the request assigning dedicated resources, e.g., dedicated resources to an identifier, and dedicated uplink segments to an identifier. Information identifying the allocated resources is conveyed to the mobile station. The mobile station determines the time of the allocated dedicated segments on the basis of a received beacon signal from the new BS sector with given timing relationships to dedicated segments. The mobile station breaks an original wireless link just prior to the time of the first assigned dedicated segment. The mobile station communicates information on the assigned dedicated segments to perform registration operations, e.g., timing synchronization and power control, establishing a new wireless link.
Abstract:
PROBLEM TO BE SOLVED: To implement soft handoffs without the need to duplicate data transmissions to multiple base stations.SOLUTION: Methods and apparatus which allow a wireless terminal to simultaneously maintain connections with multiple base stations are provided. Each wireless terminal 302 is capable of supporting multiple separate timing loops and/or other control loops for each base station connection thereby allowing the connections to operate independently and in parallel. Different control signals and/or data are transmitted on each connection that is established with base stations 304, 306. In this manner, the base stations 304, 306 receive different data allowing asynchronous data transmission. The data received by the base stations 304, 306 can be supplied to a wired asynchronous network without the need to combine the received data prior to supplying it to the wired network.
Abstract:
PROBLEM TO BE SOLVED: To provide methods and apparatus for supporting efficient paging in a wireless communications system supporting both access node based communications and peer to peer communications.SOLUTION: Paging timing intervals are set aside in the timing structure such that multi-mode wireless terminals can monitor, e.g., in an infrastructure band, for pages from a base station whether the wireless terminal is operating in a base station attachment point mode or is operating in a peer to peer communications mode. Wireless terminals operating in a peer to peer mode, e.g., using a non-infrastructure band, suspends peer to peer communications during the paging intervals. The time periods in which the wireless terminal checks pages are predetermined, so that both the wireless terminal and the base station are synchronized when a page is delivered. This synchronization helps reduce the wastage of session time in the peer to peer sessions.
Abstract:
PROBLEM TO BE SOLVED: To mitigate interference between multiple peer-to-peer devices.SOLUTION: To mitigate interference between multiple peer-to-peer devices, a plurality of receiver chains in a receiver device are configured with beamforming coefficients so as to focus reception in the direction of an intended signal from a transmitter device while minimizing reception from other directions. Similarly, the receiver device also uses a plurality of antennas and a transmitter chain to beamform in the direction of the transmitter device, thereby focusing its transmission toward the transmitter device. The receiver device also notifies nearby devices that it is employing a plurality of receive antennas. This information can be used by the nearby devices to more intelligently perform transmitter abandonment. By utilizing beamforming information to make the transmitter abandonment and/or receiver abandonment decision, better interference mitigation may be achieved.
Abstract:
PROBLEM TO BE SOLVED: To provide systems and methodologies that enable identification of peers based upon encoded signals during peer discovery in a peer-to-peer network.SOLUTION: Direct signaling that partitions a time-frequency resource into a number of segments is utilized to communicate an identifier within a peer discovery interval. A particular segment selected for transmission can signal a portion of the identifier, while the remainder can be signaled based upon tones communicated within the selected segment. Moreover, a subset of symbols within the resource is reserved (e.g., unused) to enable identification and/or correction of a timing offset (1002).
Abstract:
PROBLEM TO BE SOLVED: To provide a protocol that facilitates downlink concurrent peer-to-peer communications (within a time slot or traffic slot) between one device and many terminals as well as uplink concurrent peer-to-peer communications (within a time slot or traffic slot) between a plurality of terminals and one device.SOLUTION: The concurrent peer-to-peer communications may take place within an ad hoc network of devices. To facilitate such operation, a time-frequency structure is provided within a control channel that allows the devices and terminals to identify the peer-to-peer connections. This time-frequency structure also allows the terminals to identify other sibling terminals that have a connection with the same device, thereby allowing more efficient interference mitigation. That is, sibling peer-to-peer connections with the same device are not regarded as interferences in calculation of a signal-to-interference ratio of a certain kind of peer-to-peer connection.
Abstract:
PROBLEM TO BE SOLVED: To provide novel and improved methods for portable wireless terminal to generate and transmit a beacon signal in a wireless system in which network infrastructures are not available.SOLUTION: The beacon signal includes a sequence of beacon signal bursts, each beacon signal burst including one or more beacon symbols. A beacon symbol is transmitted using the air link resources of a beacon symbol transmission unit at a relatively high transmission power level with respect to user data symbols transmitted from the same wireless terminal, thus enabling easy detection by other wireless terminals. The beacon symbols of the beacon signal occupy a small fraction of the total available air link resources. Beacon signals can, and sometimes do, convey wireless terminal identification information, via the location of the beacon symbols within the portion of the air link resource reserved for beacon symbol transmission units.
Abstract:
PROBLEM TO BE SOLVED: To provide a method and apparatus for communication resource assignment information and for using the assignment information in a wireless communications system.SOLUTION: A mobile is assigned an identifier and a mask value as a part of a state transition message. The mobile uses the assigned identifier and/or the assigned mask value in determining whether traffic channel assignment messages are directed to a wireless terminal. Predetermined associations between assigned slots, assigned segments, and/or the mask values are utilized to limit control signaling overhead. Different groups of segments are available for assignment to different wireless terminals as a function of mask values. Different types of assignment messages use different amounts of information bits to convey the assignment. Some types of assignments use a wireless terminal identifier, while other types of assignments use a wireless terminal identifier and a mask identifier.
Abstract:
PROBLEM TO BE SOLVED: To provide a method and apparatus for antenna control in a wireless terminal.SOLUTION: Base stations transmit strip signals using strip signal segments and self-supporting modulation scheme techniques facilitating a rapid channel estimate. A strip segment occupies one OFDM symbol time interval and uses a set of downlink tones; some of the tones are left unused facilitating SIR measurement. Connected wireless terminals including multiple antennas used in combination, an antenna duplex module, a single RF receiver chain and a single RF transmitter chain, switch antenna coefficient combinations based on strip signal segment timing. The wireless terminal determines an independent downlink channel quality measurement. The wireless terminal compares channel quality measurements and selects an antenna coefficient combination to be used during non-strip signaling intervals obtaining very good antenna gain.
Abstract:
PROBLEM TO BE SOLVED: To provide a method and an apparatus supporting peer to peer communications.SOLUTION: A base station, serving as an access node for wireless terminals also communicates information supporting peer to peer communications. A base station transmits a beacon signal conveying information about a peer to peer frequency band and also receives user data from a plurality of wireless terminals using the base station as a current point of network attachment. In some embodiments, the beacon signal is transmitted into the same frequency band being used for access node based communications and identifies a different frequency band which is to be used as a peer to peer frequency band. Alternatively, or in addition, in support of peer to peer communications, a beacon signal transmission apparatus, a free standing device which does not transmit user data, transmits a sequence of beacon signal bursts, each beacon signal burst including at least one high power beacon symbol.