Abstract: Disclosed is a novel method and system for efficiently synchronizing, transmitting, and receiving data between a base station and a plurality of customer premises. A MAC coprocessor (MCP) is implemented, which works in conjunction with the MAC in order to produce a robust, high throughput communication system. The MAC coprocessor performs many of the tasks typically performed by prior art MAC's, including: during a downlink, storing a data frame, sorting the data frame according to modulation type or other criteria, determining when the data frame is full, and appending a set of CPE settings to the data frame. During an uplink, the MAC coprocessor receives all data and routes the data either to the MAC or a network backhaul. A MAC coprocessor may be used in both the base station and Customer Premises. In both the downlink and uplink processes, having a MAC coprocessor working in conjunction with the MAC may significantly increase the communication system's throughput.

Abstract: Disclosed is a novel method and system for efficiently synchronizing, transmitting, and receiving data between a base station and a plurality of customer premises. A MAC coprocessor (MCP) is implemented, which works in conjunction with the MAC in order to produce a robust, high throughput communication system. The MAC coprocessor performs many of the tasks typically performed by prior art MAC's, including: during a downlink, storing a data frame, sorting the data frame according to modulation type or other criteria, determining when the data frame is full, and appending a set of CPE settings to the data frame. During an uplink, the MAC coprocessor receives all data and routes the data either to the MAC or a network backhaul. A MAC coprocessor may be used in both the base station and Customer Premises. In both the downlink and uplink processes, having a MAC coprocessor working in conjunction with the MAC may significantly increase the communication system's throughput.

Abstract: 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.

Abstract: A system and method for mapping a combined frequency division duplexing (FDD) Time Division Multiplexing (TDM)/Time Division Multiple Access (TDMA) downlink subframe for use with half-duplex and full-duplex terminals in a communication system. Embodiments of the downlink subframe vary Forward Error Correction (FEC) types for a given modulation scheme as well as support the implementation of a smart antennae at a base station in the communication system. Embodiments of the system are also used in a TDD communication system to support the implementation of smart antennae. A scheduling algorithm allows TDM and TDMA portions of a downlink to efficiently co-exist in the same downlink subframe and simultaneously support full and half-duplex terminals. The algorithm further allows the TDM of multiple terminals in a TDMA burst to minimize the number of map entries in a downlink map.

Abstract: 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.

Abstract: A method for allocating fractional bandwidth in a fixed-frame communication system is described. The method includes calculating the integral cells per frame required at a connection, calculating the fractional cells per second required at the connection, setting a counter, adding the fractional cells per second to the counter, determining if the counter is above a preset limit, allocating an additional cell when the counter exceeds the preset limit, and reducing the counter a predetermined amount to reflect allocating the cell.

Abstract: A method and system for using half-duplex base stations and half-duplex nodes in a Frequency Division Duplexing region to provide wireless connectivity between the half-duplex base stations and customers in multiple sectors of a cell. The method and system can use two physical channels to form two logical channels. Each logical channel shares both physical channels during alternating frames of time. The half-duplex nodes can include a millimeter-wave band frequency synthesizer configured to transmit and receive on different channels to and from the half-duplex base station. Re-use patterns of the physical channels are used for deployment of half-duplex base stations and half-duplex nodes in the FDD region to minimize co-channel interference and interference due to uncorrelated rain fade. Additional methods and systems utilize full-duplex base stations and smart antenna to communicate with the half-duplex nodes.

Abstract: A method and apparatus for adaptively obtaining bandwidth requests in a broadband wireless communication system. The method and apparatus includes dynamically varying technique combinations enabling a plurality of users to efficiently request bandwidth from a shared base station. A user may “piggyback” a new bandwidth request upon, or set a “poll-me bit” within, presently allocated bandwidth. A base station may poll users, individually or in groups, by allocating unrequested bandwidth for new requests. Polling may respond to a “poll-me bit,” and/or it may be adaptively periodic at a rate based on communication status parameters, such as recent communication activity and connection QoS levels. Group polling permits a possibility of collisions. Polling policies may be established for dynamically varying user groups, or may be determined for each user. Dynamic selection of appropriate polling techniques makes use of efficiency benefits associated with each technique.

Abstract: Base stations having potentially interfering terminal stations that are geographically located on the same or similar diagonal or Line of Sight (relative to the base station) operate on a first set of time frames (e.g., “even” time frames). Similarly, base stations having potentially interfering terminal stations that are not geographically located on the same or similar diagonals operate on a second set of time frames (e.g., “odd” time frames). By alternating in their use of the even and odd frames, the potential for co-channel interference between terminal stations is minimized. Systems and methods are disclosed which reduce co-channel and adjacent channel interference between terminal stations of different cells as well as adjacent channel interference between terminal stations of adjacent cells. The methods and systems so described can be used during the deployment or expansion of a communication system in a region.

Abstract: A method and apparatus for requesting and allocating bandwidth in a broadband wireless communication system. The inventive method and apparatus includes a combination of techniques that allow a plurality of CPEs to communicate their bandwidth request messages to respective base stations. One technique includes a “polling” method whereby a base station polls CPEs individually or in groups and allocates bandwidth specifically for the purpose of allowing the CPEs to respond with bandwidth requests. The polling of the CPEs by the base station may be in response to a CPE setting a “poll-me bit” or, alternatively, it may be periodic. Another technique comprises “piggybacking” bandwidth requests on bandwidth already allocated to a CPE. In accordance with this technique, currently active CPEs request bandwidth using previously unused portions of uplink bandwidth that is already allocated to the CPE.