Wi-lan Inc.

Other

Cisco Technology, Inc.

Ensemble Communications, Inc.

Ofer Zimmerman

Kenneth L Stanwood

Brian Spinar

Yair Bourlas

Amir Serok

Peter Smith

Eli Arviv

David Gazelle

Penny Efraim

Christopher D Macy

Sheldon I Gilbert

A method and apparatus for allocating bandwidth in a broadband wireless communication system is disclosed. One embodiment uses a self-correcting bandwidth request/grant protocol. The self-correcting bandwidth request/grant protocol utilizes a combination of incremental and aggregate bandwidth requests. CPEs primarily transmit incremental bandwidth requests to their associated base stations, followed by periodic transmissions of aggregate bandwidth requests. The use of periodic aggregate bandwidth requests (that express the current state of their respective connection queues) allows the bandwidth allocation method and apparatus to be 'self-correcting'. Another embodiment utilizes an abridged bandwidth request/grant protocol to allocate bandwidth. The abridged bandwidth request/grant protocol system utilizes padding packets to request a reduction in bandwidth allocation to a CPE. A base station modem alerts a base station CPU when the BS modem receives a padding packet from a CPE. After alerting the BS CPU the method can reduce the associated CPE's bandwidth allocation.

Method and apparatus for bandwidth request/grant protocols in a wireless communication system

The invention relates to communication systems and to systems and methods for implementing adaptive call admission control (CAC) in such systems. Adaptive call admission control can determine what CPE to base station calls (connections) are allowed at any given time. CAC, coupled with precedence, can further determine what connections are suspended if less bandwidth is available than is currently committed. Multiple techniques are disclosed to select connections for suspension. These techniques include suspending enough connections through the affected CPE until there is enough bandwidth to meet the remaining commitment, randomly (or in a round robin fashion) choosing connection to suspend from the entire set of connection, and using precedence priority levels.

Adaptive call admission control for use in a wireless communication system

A self-correcting bandwidth request/grant protocol in a broadband wireless communication system. The protocol uses a combination of incremental and aggregate bandwidth requests. Stations primarily transmit incremental bandwidth requests to their associated base stations, followed by periodic transmissions of aggregate bandwidth requests. Risks are reduced that a base station erroneously issues duplicate bandwidth allocations to the same station for the same connection. Race conditions that may have occurred using only aggregate bandwidth requests are eliminated. Use of periodic aggregate bandwidth requests that express the current state of respective connection queues provides a 'self-correcting' property.

Method and apparatus for a self-correcting bandwidth request/grant protocol in a wireless communication system

A method and apparatus for packing management messages in a broadband wireless communication system. Management messages are sent across a link in packets addressed to a particular connection, where the address identifies messages which may be specially treated. Such special treatment may include recognition of an overall message conveyed in such packets as containing one or more implicit messages embedded within the overall message. Two methods are disclosed to efficiently convey such management messages. First, each packet of information sent across the link may include a message type identifier, in which case it need not be repeated in the payload of the packet, and a number of such messages may be sent within a packet. Second, a packet of information may contain mixed management messages, in which case the byte with the message type identifier should be included with each such message. In this case, an overall message may be constructed from individual management messages simply concatenated together. Using either method, the management messages are packed into packets so that messages in a first packet may be parsed and acted upon without a need for any subsequent packets which may be necessary to convey an entire message. This is accomplished by taking any message which will not fit in a first packet may be made to be ignored, such as by being replaced with a padding pattern. In this way, any subsequent packet will have management messages which begin at the start of the effective data payload. Padding may also be added before or after an end of message or trailer information which defines the end of an overall message.

Method and system for packing management messages in a communication system

A system that provides a wireless broadband connection between base stations and customer sites is described. The system includes indoor units within the base stations and customer sites and communicate across cables to outdoor units. The indoor units linked to routers, switches and other devices and services. The outdoor units transmit and receive wireless data and send it to the indoor units. The indoor units can store software instructions in the outdoor unit. This allows the indoor units to automatically detect problems with outdoor unit and download new software to them in case of an error.

Outdoor unit programming system

A method and apparatus for a self-correcting bandwidth request/grant protocol in a broadband wireless communication system is disclosed. The self-correcting bandwidth request/grant protocol utilizes a combination of incremental and aggregate bandwidth requests. In accordance with the present inventive protocol, CPEs primarily transmit incremental bandwidth requests to their associated base stations, followed by periodic transmissions of aggregate bandwidth requests. The use of incremental bandwidth requests reduces risks that a base station erroneously issues duplicate bandwidth allocations to the same CPE for the same connection. Race conditions that may have occurred using only aggregate bandwidth requests are eliminated by requiring the CPEs to request bandwidth in an incremental manner. However, use of periodic aggregate bandwidth requests (that express the current state of their respective connection queues) allows the present bandwidth allocation method and apparatus to be 'self-correcting.' The present method is self-correcting because errors that may have been introduced due to lost incremental bandwidth requests are corrected by the base stations when the aggregate bandwidth requests are received and processed. Upon receipt of the aggregate bandwidth requests, the base stations reset their records to correctly reflect the current bandwidth requirements of their associated CPEs. Periodic use of aggregate bandwidth requests provides a self-correcting bandwidth allocation protocol yet without the bandwidth overhead (e.g., bandwidth required to transmit acknowledgements) typically associated with the prior art protocols (such as the guaranteed delivery protocols).

A system that provides a wireless broadband connection between base stations and customer sites is described. The system includes indoor units within the base stations and customer sites and communicate across cables to outdoor units. The indoor units link to routers, switches and other devices and services. The outdoor units transmit and receive wireless data and send it to the indoor units. The indoor units can store software instructions in the outdoor unit. This allows the indoor units to automatically detect problems with outdoor unit and download new software to them in case of an error.

A method and apparatus for a self-correcting bandwidth request/grant protocol in a broadband wireless communication system is disclosed. The self-correcting bandwidth request/grant protocol utilizes a combination of incremental and aggregate bandwidth requests. In accordance with the present inventive protocol, CPEs primarily transmit incremental bandwidth requests to their associated base stations, followed by periodic transmissions of aggregate bandwidth requests. The use of incremental bandwidth requests reduces risks that a base station erroneously issues duplicate bandwidth allocations to the same CPE for the same connection. Race conditions that may have occurred using only aggregate bandwidth requests are eliminated by requiring the CPEs to request bandwidth in an incremental manner. However, use of periodic aggregate bandwidth requests (that express the current state of their respective connection queues) allows the present bandwidth allocation method and apparatus to be &ldquo;self-correcting&rdquo;. The present method is self-correcting because errors that may have been introduced due to lost incremental bandwidth requests are corrected by the base stations when the aggregate bandwidth requests are received and processed. Upon receipt of the aggregate bandwidth requests, the base stations reset their records to correctly reflect the current bandwidth requirements of their associated CPEs. Periodic use of aggregate bandwidth requests provides a self-correcting bandwidth allocation protocol yet without the bandwidth overhead (e.g., bandwidth required to transmit acknowledgements) typically associated with the prior art protocols (such as the guaranteed delivery protocols).

On embodiment of the system and method provides asymmetric adaptive modulation which allows uplink and downlink subframes of data to be transmitted between a base station and a CPE with different modulation schemes, thus increasing the efficiency of downlink transmissions while maintaining the stability of uplink transmissions. In systems with multiple CPEs, each CPE and base station pair can independently select their uplink and downlink modulation techniques. The system and method are also adaptive in that they adjust the modulation schemes based on, for example, signal to noise ratio measurements or bit error rate measurements.

Growing community of inventors

Modiin, Israel

Ofer Zimmerman