Qualcomm Incorporated

Samir Kapoor

Rajiv Laroia

Vincent Douglas Park

M Scott Corson

Junyi Li

Alexei Yurievitch Gorokhov

Avneesh Agrawal

Mathew Scott Corson

Arthur Stephens

Transmission techniques using configurable channels for the downlink and/or uplink are described. In one aspect, the downlink channel and/or uplink channel may be independently selected for a terminal. The terminal may establish a connection with a base station on default downlink and uplink channels. Another downlink channel and/or another uplink channel may be selected based on various factors such as channel quality, loading, and interference. The terminal would then switch to the new downlink and/or uplink channel for communication. In another aspect, the base stations broadcast sector information used by the terminals for communication and/or channel selection. The sector information may include various types of information such as the available downlink and uplink channels, the frequencies of the available channels, the loading on the available channels, and QoS information. The terminals may select a sector, a downlink channel, and/or an uplink channel based on the sector information.

Configurable downlink and uplink channels for improving transmission of data by switching duplex nominal frequency spacing according to conditions

The invention described herein enables a form of downlink macro-diversity in packet-switched cellular networks. It allows packets to be selectively delivered from a network/internetwork to an end node, e.g., a wireless communication device or terminal, over a set of available link-layer connections to/from the end node, through one or more access nodes, e.g., base stations. Downlink macro-diversity is particularly important when the link-layer connections between the end node and the corresponding access node, e.g., the access links, are subject to independent or partially correlated time variations in signal strength and interference. In accordance with the invention, the end node dynamically selects the downlink to be used out of a set of available access links on a per packet basis subject to prevailing channel conditions, availability of air-link resources and other constraints. The invention improves the robustness and efficiency of communication, overall utilization of air-link resources, and quality of service experienced by the end node.

Methods and apparatus for downlink macro-diversity in cellular networks

Techniques for mitigating temporary loss of synchronization in a wireless communication system are described. In an aspect, a cell may periodically broadcast a mode indicator to indicate synchronous operation or asynchronous operation by the cell. The cell may also broadcast its cell identity (ID), which may omit the mode indicator and would then remain unchanged when the cell switches between asynchronous and synchronous operation. In another aspect, the cell may send system time information indicative of its updated system time when switching from asynchronous operation to synchronous operation. The updated system time may be used for communication with terminals after the switch to synchronous operation. In yet another aspect, the cell may decrease its transmit power prior to switching synchronization mode, switch synchronization mode when its transmit power reaches a predetermined power level, and thereafter increase its transmit power.

Method and apparatus for mitigating temporary loss of synchronization in a wireless communication system

A method and apparatus for providing uplink macro-diversity in packet-switched networks that allows packets and/or portions of packets, e.g., frames, to be selectively sent from an end node, e.g., wireless communication device or mobile terminal, over a set of multiple communication connections, e.g., physical-layer or link-layer connections, to one or more access nodes, e.g., base stations. Uplink macro-diversity is achieved in part through intelligent selective forwarding over multiple communication connections, where the forwarding decision is controlled by the end node based on a variety of factors, e.g., physical-layer channel conditions and/or higher layer policy. The forwarding decision is executed on a rapid timescale, e.g., on a per packet basis, to adapt to the dynamically varying conditions of the set of communication connections.

Methods and apparatus for uplink macro-diversity in packet-switched cellular networks

Techniques for supporting fault tolerance in communications systems are described. Fault notification messages are communicated which may be affected by a detected/reported service disruption. End nodes receiving a fault notification message determine if the message indicates a disruption in a node that is critical to the end node receiving the message. If the indicated disruption is in a critical node, the end node takes action to ameliorate the effect of the reported condition. Fault notification messages indicating disruptions in nodes which are not critical to the end node receiving the fault notification message may be ignored once it is determined that the indicated disruption is in a node which is not critical to the end node receiving the message. The invention described herein minimizes service disruption following fault, failure or outage of critical network nodes, improving overall system robustness and resiliency.

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Doylestown, PA, United States of America

Samir Kapoor