Abstract: A method and apparatus for re-modulating an RF carrier modulated signal using a Nyquist folding frequency modulation technique. The method modulates a digitized RF carrier modulated signal with a digital sequence of {1, −1, 1, −1, . . . }, where the center frequency of the RF carrier modulated signal is at a first frequency and the sample rate of the modulating signal is at a second frequency. When the second frequency is four times the first frequency, the output of the digital modulation process is a spectrum-inverted copy of the source RF carrier modulated signal. For all other frequencies, the remodulated RF carrier modulated signal has a center frequency equal to the carrier frequency minus one-half the sample rate of the modulating signal. A spectrum inversion is then performed to recreate the spectrum of the source RF carrier modulated signal, which is now located at a different center frequency. The apparatus comprises a modulating signal source and a digital modulator.

Abstract: A digital method and apparatus modulates a stream of digitized samples from a source, by a digital representation of a carrier to provide, for example, a 6 MHz bandwidth television signal selectively centered either at 63 MHz (Channel 3), 69 MHz (Channel 4) or 5.38 MHz IF (baseband). More particularly the method includes first resampling the stream of digitized samples and then modulating the resampled stream of samples with a repeating short sequence of complex values, which complex values represent a digitized exponential carrier.

Abstract: A poppet valve assembly having a spring for holding the valve in a closed position and permitting opening of the valve in response to air pressure including valve stem alignment provided by a sleeve in engagement with the spring and having a cross pin supporting surface for engagement with the pin in shear to avoid bending.

Abstract: A distributed battery control network (14) for a battery string (12) has a plurality of sensing modules (SM) each associated with one of the batteries in the battery string (12). Each of the sensing modules has a respective sequencing input (SI) and a sequencing output (50). Said plurality modules have a sequencing input with a predetermined signature type, storing said address in a particular one of said plurality modules with said sequencing input equal to said signature type, and generating an identifying signature at an output of said particular one of plurality modules with said sequencing input equal to said signature type. A network (22) is coupled to each of the sending modules. A controller (24) is coupled to the bus and communicates with each of the sensing modules. The controller (24) loads each of the sensing modules with an address and a signature type.

Abstract: The disclosed filter structure employs parallel first and second input signal data paths. The first data path includes a digital Finite Impulse Response (FIR) filter having a small number of non-zero multiplier coefficients to define its theoretical impulse frequency response. The second data path includes plural series filters including (1) a digital FIR or Infinite Impulse Response (IIR) filter including a reduced-number of designer-chosen non-zero multiplier coefficients that tend to introduce error sources in the physical-realized filter structure's impulse frequency response and (2) a set of one or more frequency stop filters, each of which permits zero signal transmission therethrough at a different selected frequency.

Abstract: Regulating a user of a computer-based service includes receiving input about a first user from at least one other user of the computer-based service, determining a degree to which the at least one other user can influence a parameter associated with the first user, and modifying the first user's parameter based on the received input and the determined degree of influence. The first user's parameter, for example, can relate to the first user's ability to use the computer-based service.

Abstract: A method and means for self-policing and automatically rate-limiting multiple-user online forums. The preferred embodiment of the invention includes a set of rules that permit users to censure other users. A censured user has one or more “privileges” (which may include access to the online computer system or the effective message rate of a communications connection) taken away or diminished; the privilege is gradually restored if the censured user behaves. The censuring participant and other pertinent participants are notified of the effect of the censuring on the censured user. In another aspect of the invention, the online computer system automatically tracks the rate at which a user sends certain types of messages, and can message rate limit a user who uses too many system resources by sending a large number of messages in rapid succession.

Abstract: A method and means for self-policing and automatically rate-limiting multiple-user online forums. The preferred embodiment of the invention includes a set of rules that permit users to censure other users. A censured user has one or more “privileges” (which may include access to the online computer system or the effective message rate of a communications connection) taken away or diminished; the privilege is gradually restored if the censured user behaves. The censuring participant and other pertinent participants are notified of the effect of the censuring on the censured user. In another aspect of the invention, the online computer system automatically tracks the rate at which a user sends certain types of messages, and can message rate limit a user who uses too many system resources by sending a large number of messages in rapid succession.

Abstract: Regulating a user of a computer-based service includes receiving input about a first user from at least one other user of the computer-based service, determining a degree to which the at least one other user can influence a parameter associated with the first user, and modifying the first user's parameter based on the received input and the determined degree of influence. The first user's parameter, for example, can relate to the first user's ability to use the computer-based service.

Abstract: Digital remodulation systems typically include digital to analog converters which have an inherent undesirable sin(x)/x frequency response. Digital remodulated signals are typically high frequency and thus not conducive to sin(x)/x pre-correction prior to digital to analog conversion. Described herein is apparatus and a method for pre-correcting the sin(x)/x roll off of the digital to analog converter in the digital signal path prior to the digital modulator which precedes the digital to analog converter. This apparatus corresponds to a cascading of spectrally symmetric and anti-symmetric transversal filters designed to compensate a relatively small portion of the frequency response of the resulting analog signal.

Abstract: A method for generating digital carrier signals for application as the carrier to a digital modulator includes providing a first repeating sequence of complex values occurring at a given sample rate and upsampling these values to a higher sample rate. A second repeating sequence of complex values is provided, wherein respective complex values in the second repeating sequence occur at the higher sample rate. The second sequence of complex values is employed to modulate the upsampled first sequence of complex values and thereby provide the complex carrier signal.

Abstract: A sample rate conversion system converts data of a first sample rate to data of a different second sample rate. The system involves an interpolator, operating at the first sample rate and includes a first interpolation network and a delay network. The first interpolation network interpolates the first sample rate data to provide upsampled interpolated data samples according to a first sample spacing. The delay network interpolates the upsampled interpolated data to provide delayed upsampled interpolated data samples, according to a second sample spacing of higher resolution than the first sample spacing, and preceding and succeeding an original sample position. The system also includes a digital filter operating at the second sample rate for filtering the higher resolution data samples to provide the second sample rate data.

Abstract: A digital VSB modulator includes a modulator to which an ongoing sampled data stream of 1-sample-per-symbol successive PCM symbol signal samples are applied as a modulating signal. A sampled carrier stream, occurring at the rate of the signal samples, is applied as a carrier input to the modulator. The carrier stream is composed of, for example, a repeated 4-sample-sequence of 1, −1, −1, 1 sample values. The output of the modulator is applied to a bifurcated multiplexed N-tap root Nyquist FIR filter, which produces a VSB bifurcated complex output signal having a DC-centered real (±R) sampled data output stream of 1-sample-per-symbol sample values and a DC-centered imaginary (±I) sampled data output stream of 1-sample-per-symbol sample values.

Abstract: A method for balancing charge of a plurality of series-connected batteries includes alternately coupling each of a plurality of energy storage circuits across a respective one of the batteries and in parallel with each other. A charge balancing system comprises a plurality of series connected batteries and a plurality of energy storage circuits. The system also includes switching circuitry for alternately connecting each energy storage circuit across a respective one of the batteries and in parallel with each other. The switching circuitry can also be controlled to couple a plurality of the energy storage circuits across a relatively-highly-charged battery and then across a relatively-weakly-charged battery.

Abstract: A timing recovery system for a digital signal receiver receives a signal, representing successive symbols, from a transmitter. The symbols are subject to exhibiting multiple symbol rates. The system derives a sample enable signal from the received input signal and employs a single, fixed frequency oscillator. A source of samples representing the received signal are sampled at a fixed frequency. An interpolator is coupled to the sample source and is responsive to a control signal. The interpolator produces samples taken at times synchronized to the successive symbols from the transmitter. A phase error detector is coupled to the interpolator, detects a phase error between the sample times of the transmitter synchronized samples produced by the interpolator and times of the successive transmitter symbols, and supplies a phase error signal. The phase error signal is coupled to one input terminal of a summer and a source of a nominal delay signal is coupled to the other.

Abstract: A receiver is arranged for receiving a transmitted quadrature amplitude modulated (QAM) signal representing successive symbols, and including an in-phase (I) component and a quadrature (Q) component. In such a receiver, a timing recovery system includes a source of samples representing the QAM signal produced at a fixed frequency. A first chain of processing circuitry for the I component includes a first demodulator, coupled to the sample source, for demodulating the I component of the QAM signal to baseband; and a first interpolator, coupled to the first demodulator and responsive to a control signal, for producing I component samples taken at times synchronized to the transmitted symbols.

Abstract: A filtering circuit suitable for use in a video sample rate converter provides a constant direct current (DC) gain irrespective of realization errors, and reduces hardware requirements. The circuit includes an input terminal for receiving an input signal. A first delay unit delays the input signal to generate a first delayed signal. A subtracting unit subtracts the input signal from the first delayed signal to generate a difference signal. A second delay unit delays the difference signal to generate a second delayed signal. A reference delay unit delays the first delayed signal by a predetermined reference time period to generate a reference signal. A filtering unit filters the second delayed signal to generate a filtered signal. An adding unit adds the reference signal to the filtered signal to generate an output signal.

Abstract: Molds for injection molding tire components have controlled temperature passages leading to a manifold surrounding each mold cavity. The manifold is positioned to minimize weld lines in the injected tire component. In addition, a narrow gate opening between the manifold and mold cavity provides an elevated temperature of the injected material for decreasing the curing time of the tire component in the mold. Blade members may support and position tire components such as bead apex assemblies in the mold. These tire components may be unloaded by an unloader ring in communication with a source of vacuum for pulling the tire component out of the mold.

Abstract: A method and apparatus for testing semi-conductor chips is disclosed. The individual semiconductor chips have I/O contacts. The apparatus is provided with an interposer that has contacts corresponding to the contacts on the semiconductor chip. Both the chip and the interposer contacts can be any known type including metal ball, bumps, or tabs or may be provided with dendritic surfaces. The chip contacts are first brought into relative loose temporary contact with the contacts on the interposer and then a compressive force greater that 5 grams per chip contact is applied to the chip to force the chip contacts into good electrical contact with the interposer contacts. Testing of the chip is then performed. The tests may include heating of the chip as well as the application of signals to the chip contacts. After testing the chip is removed from the substrate.

Abstract: A method and apparatus for testing semi-conductor chips is disclosed. The individual semiconductor chips have I/O contacts. The apparatus is provided with an interposer that has contacts corresponding to the contacts on the semiconductor chip. Both the chip and the interposer contacts can be any known type including metal ball, bumps, or tabs or may be provided with dendritic surfaces. The chip contacts are first brought into relative loose temporary contact with the contacts on the interposer and then a compressive force greater that 5 grams per chip contact is applied to the chip to force the chip contacts into good electrical contact with the interposer contacts. Testing of the chip is then performed. The tests may include heating of the chip as well as the application of signals to the chip contacts. After testing the chip is removed from the substrate.