Abstract: A replacement bumper for a snowmobile ski is provided and methods for using the same. The replacement bumper has an abutment surface that makes contact with a spindle of a snowmobile in order to increase the contact surface area of a rear portion of a snowmobile ski and the ground and/or increase the weight being distributed on the rear portion of the snowmobile ski, which prevents the darting or tracking of the snowmobile ski. Also, includes is a method for removing an OEM bumper from a snowmobile ski assembly and installing a replacement bumper into said snowmobile ski assembly.

Abstract: A replacement bumper for a snowmobile ski is provided and methods for using the same. The replacement bumper has an abutment surface that makes contact with a spindle of a snowmobile in order to increase the contact surface area of a rear portion of a snowmobile ski and the ground and/or increase the weight being distributed on the rear portion of the snowmobile ski, which prevents the darting or tracking of the snowmobile ski. Also, includes is a method for removing an OEM bumper from a snowmobile ski assembly and installing a replacement bumper into said snowmobile ski assembly.

Abstract: A replacement bumper for a snowmobile ski is provided and methods for using the same. The replacement bumper has an abutment surface that makes contact with a spindle of a snowmobile in order to increase the contact surface area of a rear portion of a snowmobile ski and the ground and/or increase the weight being distributed on the rear portion of the snowmobile ski, which prevents the darting or tracking of the snowmobile ski. Also, includes is a method for removing an OEM bumper from a snowmobile ski assembly and installing a replacement bumper into said snowmobile ski assembly.

Abstract: A replacement bumper for a snowmobile ski is provided and methods for using the same. The replacement bumper has an abutment surface that makes contact with a spindle of a snowmobile in order to increase the contact surface area of a rear portion of a snowmobile ski and the ground and/or increase the weight being distributed on the rear portion of the snowmobile ski, which prevents the darting or tracking of the snowmobile ski. Also, includes is a method for removing an OEM bumper from a snowmobile ski assembly and installing a replacement bumper into said snowmobile ski assembly.

Abstract: A high speed data transfer system includes a WAU (201) which is utilized to provide high speed access to satellite transferred data. The system is configured such that a plurality of data utilization (205) may access the high speed data via wireless links to the WAU (201). Advantageously, high speed data services may be provided to users without the users requiring individual satellite antennas.

Abstract: Apparatus are provided for a communication signal processing apparatus having a channel estimator configured to generate a first channel estimation at a first time point, a linear predictor coupled to the channel estimator, and an adaptive filter coupled with the linear predictor. The linear predictor is configured to predict a second channel estimation based on a second time point and a channel frequency. The second time point is concurrent or subsequent to the first time point. The second channel estimation includes a first coefficient. The linear predictor includes a first predictor having a sample time point. The first predictor is configured to generate the first coefficient of the second channel estimation based on the sample time point and the second time point. The sample time point is prior to the second time point. The adaptive filter is configured to recursively determine the second channel estimation.

Abstract: An embodiment of a method for parameterizing an input signal includes non-linearly transforming the input signal, removing higher order terms by passing the input signal through a low pass filter to produce a linear combination of data symbols and DC components, solving for the DC components, separating a plurality of mixed baseband signals from the input signal, and coordinate transforming each of the separated signals from polar coordinates to Cartesian coordinates. An embodiment of a receiver includes a non-linear transform operator receiving a digitized input signal and adapted to produce a linear combination of data symbols, DC components, and carrier effects; a low-pass filter for removing higher order terms; a separator unit for separating the plurality of mixed baseband signals; and a coordinate transform for converting the separated signals from polar coordinates to Cartesian coordinates.

Abstract: Methods and apparatus are provided for distributed polyphase spread spectrum communication and non-contiguous spectrum underlay. The method includes polyphase channelizing a direct sequence spread spectrum (DSSS) signal, determining available spectrum in an observed frequency range having a noise floor based on detection of polyphase users below the noise floor, distributing the polyphase channelized signal among the available spectrum, and interference mitigation using a combination of standard signal detection and cyclostationary feature detection methods.

Abstract: A rotary cutter and end bit therefore is provided for cleaning and clearing debris and roots from a pipe. The cutter comprises a support housing having a plurality of radially extending skid fins, which help position the chain root cutter in the center of the pipe. The support housing carries a rotor and the rotor rotates relative thereto. A motor supported by the support housing is adapted to rotate the rotor. A plurality of linkages extends radially from the rotor and attaches at least one end bit to the rotor of the chain root cutter. The end bit comprises a hard wear resistant material, such as carbide, that faces radially outward and increases the wear life of the end bit. The wear resistant material may comprise carbide chips that continuously provide sharp edges over the life of the end bit.

Abstract: A wear rod for a snowmobile ski is provided that contains multiple wear edges. The wear rod includes a longitudinally extending host bar having longitudinally extending grooves. Strips of a harder second material are integrally mounted in the grooves to increase the wear resistance of the wear rod. The strips define wear edges that contact the trail surface as the snowmobile turns or moves in a straight direction. The wear edges are located such that as the snowmobile ski turns, the wear rod cants and a portion of the load of the snowmobile shifts from one wear edge to another wear edge. The wear edges are also arranged such that the wear edges are self-sharpening to maintain the functional life of the wear rod.

Abstract: A high speed data transfer system includes a WAU (201) which is utilized to provide high speed data access to satellite transferred data. The system is configured such that a plurality of data utilization devices (205) may access the high speed data via wireless links to the WAU (201). Advantageously, high speed data services may be provided to users without the users requiring individual satellite antennas.

Abstract: A high speed data transfer system includes a WAU (201) which is utilized to provide high speed data access to satellite transferred data. The system is configured such that a plurality of data utilization devices (205) may access the high speed data via wireless links to the WAU (201). Advantageously, high speed data services may be provided to users without the users requiring individual satellite antennas.

Abstract: An orthogonal frequency division multiplexed wideband communication system provides improved time and frequency synchronization by inserting an unevenly spaced pilot sequence within the constellation data. A receive correlates the received data using the unevenly spaced pilot sequence. The pilot sequence is generated with a maximum length pseudo random noise code and inserted into frequency bins having prime numbers.

Abstract: An apparatus is disclosed for continuous load optimization of wireless communication networks by making use of statistical data about both the communication medium characteristics and the characteristics of messages that users desire to send over the network. The network comprises a network control base station (20) and a plurality of slave stations (22). One or more applications (72, 104) are associated with each station which are used to generate the messages in digital format. Each application is coupled to a protocol stack (88) that defines the required characteristics of the data and changes to the data that occur during the communication process. An interface (90) is coupled to the layers of each protocol stack (88) to allow tuning of the message characteristics to maximize successful transmission with minimum message latency.

Abstract: A non-linear signal classifier (26) includes a polynomial expansion unit for expanding signal feature vectors determined by a feature extraction unit (25) for a received signal. The expanded signal feature vectors are each combined with a plurality of signal classification models that are stored in a model memory (76). The signal classification models are each associated with a particular signal type that is recognized by the non-linear signal classifier. A scoring unit (72) generates a score for each of the signal classification models based on the result of the combination. The scores are analyzed by a selection unit (74) which determines which of the signal classification models (i.e., which of the signal types) most likely represents the received signal. Training equipment (60) is also provided for training the non-linear signal classifier (26) to recognize new signal types.

Abstract: The invention relates to a communication system (300) having a receiver (304) that is capable of performing targeted interference suppression. An interference classifier (314) within the receiver (304) analyzes a signal received from a channel (306) and identifies and classifies interference components within the signal. An interference suppressor (316) then suppresses the interference components in the signal based on interference type. In one embodiment, the interference suppressor (316) includes a plurality of interference suppression modules that are each optimal for suppressing certain interference types. The interference suppressor (316) selects one of the interference suppression modules based on the type of interference present in the received signal. In another embodiment, a hybrid interference mitigation system (10) is provided by combining targeted interference suppression, frequency hopping adaptation, and processing gain adaptation.

Abstract: The invention relates to a communication system (300) having a receiver (304) that is capable of performing targeted interference suppression. An interference classifier (314) within the receiver (304) analyzes a signal received from a channel (306) and identifies and classifies interference components within the signal. An interference suppressor (316) then suppresses the interference components in the signal based on interference type. The interference suppressor (316) includes a plurality of interference suppression modules that are each optimal for suppressing certain interference types. In one embodiment, one or more of the interference suppression modules perform interference suppression using modal moment estimates to identify different modes within the signal.

Abstract: The invention relates to a communication system (300) having a receiver (304) that is capable of performing targeted interference suppression. An interference classifier (314) within the receiver (304) analyzes a signal received from a channel (306) and identifies and classifies interference components within the signal. An interference suppressor (316) then suppresses the interference components in the signal based on interference type. In one embodiment, the interference suppressor (316) includes a plurality of interference suppression modules that are each optimal for suppressing certain interference types. The interference suppressor (316) selects one of the interference suppression modules based on the type of interference present in the received signal. In another embodiment, a hybrid interference mitigation system (10) is provided by combining targeted interference suppression, frequency hopping adaptation, and processing gain adaptation.

Abstract: The present invention relates to a communications system (100) that is capable of adapting to an unknown or varying spectral environment in a channel (14) between two communications units (12, 16). The system (100) maintains a spectral profile of the channel (14) and uses the spectral profile to determine appropriate transmit parameters for the system (100). The system (100) can be programmed to provide an optimal transmit signal for achieving a predetermined performance goal (such as, for example, maximum data rate at a given bit error rate (BER)) in light of the spectral environment in the channel (14). In one embodiment, the spectral profile is maintained in a spectrum table memory (27) that is periodically (or continuously) updated.

Abstract: A sound monitoring system includes a resonator platform comprised of musician support plate, a base plate, and at least one transducer. The musician support plate acts as a surface upon which the user may stand or sit. In response to high-frequency filtered and amplified electrical signals from a sound source, the transducer of the resonator platform imparts vibrational energy to the musician support plate, which in turn acts as a diaphragm to impart low frequency sounds to the musician by touch without generating appreciable audible energy. The base and musician support plates may have various geometric shapes and sizes, and are composed of materials suitable for transmitting vibrational energy.