Abstract: Multiple Input Multiple Output (MIMO) technology in conjunction with the IEEE 802.11 standard enables simultaneous communication of data packets to or from multiple users in the same frequency. Spatial divisional multiple access (SDMA) is thus provided. In this way, system capacity can be increased to an extent that depends on available antenna resources and the multipath characteristics of the communication channel. Doubling or quadrupling of network throughput can be achieved.

Abstract: An expandable coupling arrangement for coupling first and second tubulars includes a male thread portion on an end of the first tubular and a female thread portion on an end of the second tubular. The thread portions comprise dovetail threads having flanks, roots and crests, wherein the flanks are inclined at an angle of greater than 10°.

Abstract: The MAC layer of a wireless communication standard is modified to facilitate MIMO (multiple input multiple output) processing and thereby increase capacity and/or spectral efficiency. In one implementation, the IEEE 802.11a standard is modified in this way. A contention free period (CFP) is divided between MIMO communications and non-MIMO communications. An access point may maintain a list of nodes operating in MIMO mode and nodes operating in non-MIMO mode.

Abstract: Methods, apparatuses and systems directed to providing location services in a wireless network. According to one implementation of the present invention, the wireless network infrastructure provides high-accuracy location information via location services to wireless clients. In one embodiment, during an advertisement phase, a location server provides a list of available location services to wireless clients via a central controller. In another embodiment, during a presentation phase, a driver of the wireless client presents the available location services to one or more applications of the wireless client. In another embodiment, during a request phase, the driver transmits a location service request to the central controller, which passes the location service request to the location server.

Abstract: Methods, apparatuses, and systems directed to facilitating troubleshooting wireless connectivity issues in a wireless network. In accordance with one embodiment of the present invention, either a diagnostic supplicant in the wireless client or a diagnostic manager initiates a troubleshooting protocol between the diagnostic supplicant and the diagnostic manager over a diagnostic link in response to one or more events. In one embodiment, after the diagnostic supplicant establishes a link to a diagnostic manager via a diagnostic link, the diagnostic supplicant generates and transmits a problem report to the diagnostic manager. The problem report initiates a troubleshooting protocol between the diagnostic manager and the diagnostic supplicant.

Abstract: Methods, apparatuses, and systems directed to reliably providing emergency services to wireless clients. In one embodiment, a wireless client determines if an attempt to transmit an emergency message exists. If so, the wireless client determines if one or more wireless access points support expedited bandwidth capabilities. If so, the wireless client notifies one of the wireless access points that the wireless client has an expedited bandwidth request.

Abstract: A tubing expansion device is adapted to be advanced axially, without rotation, through tubing to be expanded. The device comprises a body and a plurality of expansion members mounted on the body, the expansion members being independently radially movable. The expansion members may be rotatable, or may be non-rotating.

Abstract: A method, apparatus, and software containing computer readable code to implement the method implemented in a first wireless device. The method includes, for a particular network identifier active in a wireless network, transmitting frames configured to advertise the infrastructure network of the particular network identifier. The transmitting of off-channel beacons is in a provided channel different than the channel in which the access point of the infrastructure wireless of the particular network identifier transmits beacon frames. The transmitting of off-channel beacons further is at a rate higher than the beacon rate frame at which the access point of the infrastructure wireless of the particular network identifier transmits beacon frames.

Abstract: A discrete multitone stacked-carrier spread spectrum communication method is based on frequency domain spreading including multiplication of a baseband signal by a set of superimposed, or stacked, complex sinusoid carrier waves. In a preferred embodiment, the spreading involves energizing the bins of a large Fast Fourier transform (FFT). This provides a considerable savings in computational complexity for moderate output FFT sizes. Point-to-multipoint and multipoint-to-multipoint (nodeless) network topologies are possible. A code-nulling method is included for interference cancellation and enhanced signal separation by exploiting the spectral diversity of the various sources. The basic method may be extended to include multielement antenna array nulling methods for interference cancellation and enhanced signal separation using spatial separation. Such methods permit directive and retrodirective transmission systems that adapt or can be adapted to the radio environment.

Abstract: A tubing expansion device (20) is adapted to be advanced axially, without rotation, through tubing (10) to be expanded. The device (20) comprises a body (22) and a plurality of expansion members (30,32,34) mounted on the body (22), the expansion members (30,32,34) being independently radially movable. The expansion members may be rotatable, or may be non-rotating.

Abstract: A discrete multitone stacked-carrier spread spectrum communication method is based on frequency domain spreading including multiplication of a baseband signal by a set of superimposed, or stacked, complex sinusoid carrier waves. In a preferred embodiment, the spreading involves energizing the bins of a large Fast Fourier transform (FFT). This provides a considerable savings in computational complexity for moderate output FFT sizes. Point-to-multipoint and multipoint-to-multipoint (nodeless) network topologies are possible. A code-nulling method is included for interference cancellation and enhanced signal separation by exploiting the spectral diversity of the various sources. The basic method may be extended to include multielement antenna array nulling methods for interference cancellation and enhanced signal separation using spatial separation. Such methods permit directive and retrodirective transmission systems that adapt or can be adapted to the radio environment.

Abstract: A discrete multitone stacked-carrier spread spectrum communication method is based on frequency domain spreading including multiplication of a baseband signal by a set of superimposed, or stacked, complex sinusoid carrier waves. In a preferred embodiment, the spreading involves energizing the bins of a large Fast Fourier transform (FFT). This provides a considerable savings in computational complexity for moderate output FFT sizes. Point-to-multipoint and multipoint-to-multipoint (nodeless) network topologies are possible. A code-nulling method is included for interference cancellation and enhanced signal separation by exploiting the spectral diversity of the various sources. The basic method may be extended to include multielement antenna array nulling methods for interference cancellation and enhanced signal separation using spatial separation. Such methods permit directive and retrodirective transmission systems that adapt or can be adapted to the radio environment.

Abstract: According to a particular embodiment, a method for assisting in a handoff is provided that includes receiving signaling from one or more access points, which may transmit information to a mobile station. The information may be used to execute a handoff from an enterprise network to a cellular network or from the cellular network to the enterprise network.

Abstract: A method for evaluating number of additional admissible calls for use in call admission control includes tracking a percentage of channel busy time and transmission time of downlink and uplink voice packets, receiving a call admission request, and calculating the number of admissible calls. The number of admissible calls is calculated based on a channel bandwidth requirement determined from the percentage of channel busy time and a voice packet queuing requirement determined from the transmission time of downlink and uplink voice packets. The call admission request is approved if the number of admissible calls is greater than one and rejected if the number of admissible calls is less than one.

Abstract: An apparatus and method for switching a mobile processing device from communicating over a wireless connection with a first base unit to a second base unit based upon latency. In accordance with this invention, the mobile processing device determines latency information for packets being transmitted over the wireless connection to and from a base unit. The latency information is compared to a threshold value. If the latency information is greater than the threshold value, the mobile processing device adjusts parameters of the wireless connection between the mobile processing device and the network.

Abstract: A technique for network planning that includes an interface for guiding a network user through the network allocation process, such as defining groups of clients based on their capabilities. Portions of the wireless local area network infrastructure, e.g., access points, are allocated among the groups. When a client attempts to associate with an access point, the access point determines the client capabilities. If the client is supported by the access point, the access point allows the client to associate and sends the client a message that contains a prioritized list of other nearby access points allocated to service that client, otherwise the access point sends a prioritized roaming list of nearby access points to the client that are allocated to serve that type of client. Feedback is provided by the network infrastructure enabling a network user or the network to automatically reallocate resources based on the feedback.

Abstract: An expandable coupling arrangement for coupling first and second tubulars includes a male thread portion on an end of the first tubular and a female thread portion on an end of the second tubular. The thread portions comprise dovetail threads having flanks, roots and crests, wherein the flanks are inclined at an angle of greater than 10°.

Abstract: Interferometric apparatus and methods for reducing the effects of coherent artifacts in interferometers. Fringe contrast in interferograms is preserved while coherent artifacts that would otherwise be present in the interferogram because of coherent superposition of unwanted radiation generated in the interferometer are suppressed. Use is made of illumination and interferogrammetric imaging architectures that generate individual interferograms of the selected characteristics of a test surface from the perspective of different off-axis locations of illumination in an interferometer and then combine them to preserve fringe contrast while at the same time arranging for artifacts to exist at different field locations so that their contribution in the combined interferogram is diluted.

Abstract: A discrete multitone stacked-carrier spread spectrum communication method is based on frequency domain spreading including multiplication of a baseband signal by a set of superimposed, or stacked, complex sinusoid carrier waves. In a preferred embodiment, the spreading involves energizing the bins of a large Fast Fourier transform (FFT). This provides a considerable savings in computational complexity for moderate output FFT sizes. Point-to-multipoint and multipoint-to-multipoint (nodeless) network topologies are possible. A code-nulling method is included for interference cancellation and enhanced signal separation by exploiting the spectral diversity of the various sources. The basic method may be extended to include multielement antenna array nulling methods for interference cancellation and enhanced signal separation using spatial separation. Such methods permit directive and retrodirective transmission systems that adapt or can be adapted to the radio environment.

Abstract: A tubing expansion device (20) is adapted to be advanced axially, without rotation, through tubing (10) to be expanded. The device (20) comprises a body (22) and a plurality of expansion members (30,32,34) mounted on the body (22), the expansion members (30,32,34) being independently radially movable. The expansion members may be rotatable, or may be non-rotating.