Ntt Docomo, Inc.

Xia Gao

Gang Wu

Fujio Watanabe

Moo Ryong Jeong

Ravi Kumar Jain

Toshiro Kawahara

A method supports scalable and reliable multicast in a wireless network with a large bandwidth-delay product. In this method, acknowledgement packets from different receivers experiencing the same number of data packets lost are assigned the same time slots. This method can be combined with other loss recovery techniques, such as forward error correction (FEC) recovery, proactive protection, feedback suppression and collision detection. Scalability is achieved as bandwidth usage relates only to the number of packets transmitted, rather than the number of receivers.

Method for supporting scalable and reliable multicast in TDMA/TDD systems using feedback suppression techniques

Methods for increasing power saving in a station that sends or receives frames in an ad hoc wireless network (e.g., IBSS), while allowing the station to enter a power-saving mode quickly upon completion of scheduled tasks. At the same time, a method of the present invention allows two stations in the ad hoc wireless network to infer each other's power management mode without requiring an ATIM/ACK exchange between the STAs within an ATIM window. Consequently, a station may enter a power-saving mode promptly without impairing the station's ability to receive packets. In one embodiment, a 'more data' field is used between stations to exchange information. Stations with various computation abilities provide information under different time constraints. The stations may enter power-saving modes that send multicast/broadcast frames or use promiscuous mode within an ATIM window.

Method and apparatus for power saving in beacon generation of wireless networks in ad hoc mode

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.

System and method for supporting quality of service in vertical handovers between heterogeneous networks

Channel scanning for wireless networks, such as Wireless Local Area Networks (WLANs), generally provides a wireless station with the information on the available WLAN resources, such as the frequency band and the maximum transmission power. The present invention provides safe and fast domain-aware channel scanning, enabling a wireless station to comply with applicable local regulations, in spite of the possibility of domain changes, with short channel-scanning time. Fast channel scanning is accomplished by active channel scanning if valid domain information is available and there is no possibility of domain change. Also, domain-independent channels, if any, are first scanned using active scan to get domain information faster.

System and method for channel scanning in wireless networks

Disclosed herein are systems and methods for communicating a number of data flows on a single communications channel. In one embodiment, a method of communicating a number of data flows on a shared communications channel includes the acts of (1) calculating a set of optimum goodput rates for the data flows, in order to maximize a total utility of the data flows, (2) calculating a set of optimum throughput rates for the data flows based on the optimum goodput rates, and (3) transmitting the data flows on the shared communications channel with the optimized throughput rates. Optimization is preferably done using utility functions that indicate the utility of the data flows as a function of their goodput rates. The method can additionally block temporarily a transport layer of at least one of the data flows if the transport layer of that data flow is bottlenecked.

Systems and methods for goodput guarantee through adaptive fair queuing

A method for maintaining a quality of service in a wireless communication network is introduced. A reservation is created in a first data path between a home agent and a first foreign agent for data flow between the home agent and a wireless terminal. When the wireless terminal associates with a second foreign agent, a quality of service supportive second data path may be created between the first foreign agent and the second foreign agent. The data flow may be routed over the first and second data paths to maintain the quality of service for the data flow. A wireless communication network may include first downstream and reverse tunnels coupling a home agent and a first foreign agent, each tunnel having a reservation to maintain a quality of service. Second downstream and reverse tunnels may couple a home agent and a second foreign agent. All or part of the resources reserved by the first tunnels may be shared with the second tunnels when a wireless terminal hands over from the first foreign agent to the second foreign agent.

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Cupertino, CA, United States of America

Xia Gao