5704 results about "Signal frequency" patented technology

An apparatus and method for establishing closed dielectrophoretic potential cages and precise displacement thereof comprising a first array of selectively addressable electrodes, lying on a substantially planar substrate and facing toward a second array comprising one electrode. The arrays define the upper and lower bounds of a micro-chamber where particles are placed in liquid suspension. By applying in-phase and counter-phase periodic signals to electrodes, one or more independent potential cages are established which cause particles to be attracted to or repelled from cages according to signal frequency and the dielectric characteristics of the particles and suspending medium. By properly applying voltage signal patterns into arrays, cages may trap one or more particles, thus permitting them to levitate steadily and/or move. In the preferred embodiment, where one array is integrated on a semiconductor substrate, displacement of particles can be monitored by embedded sensors.

Described are apparatus and methods for electrically modulating a nerve in a mammal. An electrical signal that includes a signal intensity pattern and a signal frequency pattern is delivered to a nerve. The combination of the signal intensity pattern and the signal frequency pattern is effective to result in weight loss, fat loss, and/or lean-mass gain, in a mammal. In some embodiments the nerve is modulated in response to a physiological parameter. In some embodiments, the physiological parameter is measured by a sensor.

A method for dynamically updating at least one pre-defined value of a parameter used to identify at least one operational mode of an object for user interaction with a digitizer sensor during interaction with the digitizer sensor comprises detecting signal outputs from a plurality of sensing elements of a digitizer sensor during user interaction with the digitizer sensor; characterizing a pattern formed by the signal outputs from the plurality of sensing elements; identifying a pre-defined event associated with an operational mode of the object based on the pattern; determining a value of the parameter from the signal outputs in response to identification of the pre-defined event; and updating the pre-defined value used to identify the operational mode based on the value of the parameter determined from the identified event.

Client signals to be transported in a transmission network, particularly an optical transmission network, may have different payload envelope rates and are digitally mapped on the client egress side into first transport frames (also referred to as iDTF frames, or intra-node or internal digital transport frames), at the client side for intra-transport within terminal network elements (NEs) and further digitally mapped into second transport frames (also referred to as DTFs or digital transport frames) for inter-transport across the network or a link which, through byte stuffing carried out in the first transport frames so that they always have the same frame size. As a result, the system of framers provides for a DTF format to always have a uniformly universal frame rate throughout the network supporting any client signal frequency, whether a standard client payload or a proprietary client payload, as long as its rate is below payload envelope rate of the client signal. At the client signal ingress side, the signal are digitally demapped from the second transport frames (DTF format) into the first transport frames where the stuff bytes are removed and accordingly processed at an intermediate node element before further transport, or digitally demapped from the first transport frames (iDTF format) to reproduce or reassemble the client signal or signals comprising the client payload at the client payload envelope rate for reception at the client's equipment. Among various features disclosed, two predominate features are (1) a single channel or network rate for transport of all signals between network elements (NEs) and end terminal network elements and (2) the digitally wrapping of different types of payloads into N client side or first frames using stuff bytes to render each client side frame size equal to a predetermined value. Then the stuffed first frames are wrapped into line side or second frames for transport over the network at the same high speed line rate for all digitally wrapped client signals. The client side framers may be, for example, running at the lowest signal rate encountered, to digitally wrap then into parallel N client signals or digitally wrap a client signal multi-sected into N parts, where these two different client signals have different payload rates.

The invention discloses a bearing fault detection method based on a manner of controlling stochastic resonance by an external periodic signal. According to the method provided in the invention, after a bearing fault signal is converted by a variable metric method, the converted signal is input in a bistable system; meanwhile, an external single frequency periodic signal is taken as a control signal to act directly on the system; contact barrier height of the bistable system and an escape rate of Kramers are changed by continuously adjusting an amplitude of the control signal. Therefore, stochastic resonance can be generated or increased artificially; a spectral value of an output power spectrum at the position of an input signal frequency can be effectively improved; and thus a characteristic signal of a bearing fault can be detected accurately at last. The detection method provided in the invention enables the effective control of the stochastic resonance to be realized, thereby providing a novel method for early detection of equipment faults.

A direct sequence spread spectrum receiver samples an incoming signal and stores the sample in memory. Prior to sampling and storage, the incoming signal is translated to an IF signal. Also prior to storage, the IF signal is corrected for a frequency offset signal. The frequency offset may be caused by many sources, Doppler shift or local oscillator error, for example. Once the signal is corrected for the frequency offset, the signal sample is stored in memory. The signal sample is read from memory as necessary to process the signal. Such a receiver is useful in global positioning satellite (GPS) signal processing where the incoming signal contains several satellite transmissions encoded with CDMA encoding.

A method and device for managing and controlling a scanning system that incorporates multiple oscillating scanners is provided by the present invention. In accordance with the preferred embodiment, a resonant frequency is determined for each of the scanners. A drive signal for driving the oscillating scanners is generated based upon the determined resonant frequencies. An amplitude adjustment circuit determines the difference between the drive signal frequency and the resonant frequency of each oscillating scanner and adjusts the amplitude of the drive signal provided to that particular oscillating scanner such that scan amplitude of each oscillating scanner is approximately equal. The offset from the resonant frequency is also used to calculate a phase adjustment for the drive signal to insure that the oscillating scanners are operating in tandem.

The present invention relates to providing an improved phase controlled dimming LED driver circuitry, system and a method thereof, which is configured to enable dimming intensity of light generated by a light source, said phase controlled dimming driver circuitry being connected to a phase control dimmer that provides to it a regulated alternating current (AC) signal, wherein said phase controlled dimming driver circuitry does not include a microprocessor and pulse width modulates its output current, provided to said light source, at a frequency unrelated to the AC signal frequency. Further, the phase controlled dimming driver circuitry applies amplitude modulation (AM) and pulse width modulation (PWM) substantially simultaneously to the output current provided to the light source.

A wireless communication apparatus receives an quadrature modulated signal, generate a local signal having a frequency different from a center frequency of the quadrature modulated signal, performs quadrature demodulation on the quadrature modulated signal by using the local signal, to obtain an I channel signal and a Q channel signal, performs Fourier transform on the I channel signal and the Q channel signal, to obtain signals in a frequency domain, and calculates a first correction coefficient for correcting phase distortion and amplitude distortion caused by the quadrature demodulation by using pairs of signals among the signals, each of the pairs are located at symmetrical frequency positions with respect to the frequency of the local signal.

The invention discloses a power signal frequency detection method and a power signal frequency detection system based on phase modulation. The method comprises the steps: sampling a power signal according to preset signal time span and preset sampling frequency, so as to obtain an input signal sequence; measuring the frequency of the input signal sequence, so as to obtain the initial frequency of the power signal, and subtracting the input signal sequence and the plus or minus 1 Pi phase-shift sequence of the input signal sequence by using the initial frequency as reference frequency, so as to obtain two phase modulation sequences of which phases change along with the input signal frequency; respectively mixing, filtering and integrating the two phase modulation sequences, so as to obtain the phases of the two phase modulation phases for frequency measurement. By implementing the power signal frequency detection method and the power signal frequency detection system, frequency measurement results with higher accuracy can be obtained.

A self-interference signal cancellation circuit includes a transmitter for transmitting a transmit signal, a plurality of signal paths, a controller, and a receiver for receiving a signal. Each signal path includes a delay element and a variable attenuator having attenuation levels set by the controller. A combiner generates an output signal by combining outputs of the signal paths. The circuit computes a matrix based on first and second output signals associated with first and second attenuation levels. The controller concurrently varies the attenuation level of each signal path so that a product of the matrix and the attenuation levels of the signal paths is substantially equal to the received signal. The circuit may iteratively compute the matrix using different transmit signal frequencies or with an FFT. The controller iteratively varies the attenuation level of the attenuators until a sum of the product and the received signal satisfies a predefined condition.

An oscillating signal in an oscillator is caused to phase shift toward the phase of an input signal coupled to the oscillating signal. The resonant frequency of the oscillator is about equal to an integer multiple of the frequency of the input signal. The input signal may be generated in a pulse generator to have an input pulse duration less than or equal to that of the oscillating signal. The oscillator circuit may be used as a filter to filter pulse width variations or to filter jitter from a reference clock. The oscillator circuit may also serve as a buffer by amplifying the input signal. Phase interpolation can be obtained by coupling at least one input signal with at least one oscillating signal.

A Multi-carrier Switch Converter (“MCSC”) for multiplexing a plurality of input signals received at the MCSC into a single MCSC output signal is disclosed. The MCSC may include a Multi-port Selector Switch, wherein the Multi-port Selector Switch receives the plurality of input signals and produces a Multi-port Selector Switch output, wherein the Multi-port Selector Switch output includes a plurality of switched output signals and a frequency translation block in signal communication with the Multi-port Selector Switch, wherein the frequency translation block receives the Multi-port Selector Switch output and frequency translates each switched output signal of the plurality of switched output signals to plurality of translated signals, wherein each translated signal has a fixed carrier frequency. Additionally, the MCSC may include a combiner in signal communication with frequency translation block, wherein the combiner receives the plurality of frequency translated signals and combines them to produce the single MCSC signal.

Frequency modification circuitry may be employed as part of a crystal oscillator circuit to generate a reference signal with adjustable frequency. The frequency modification circuitry may be implemented as part of a crystal oscillator circuit that includes digitally controlled crystal oscillator (“DCXO”) circuitry and a crystal. The frequency modification circuitry may adjust the frequency of the reference signal in response to one or more frequency control signals. In one example, the frequency modification circuitry may include variable capacitors such as one or more continuously variable and/or discretely variable capacitors for providing coarse and/or fine adjustment of the reference signal frequency.

A circuit and method for controlling a switching regulator utilize a combination of variable off-time control (or frequency control) and variable peak current control to achieve high efficiency at a wide range of load conditions. A non-linear control circuit receives an error voltage and generates a first control signal for controlling a frequency control circuit and a second control signal for controlling a peak current control circuit. The frequency control circuit and the peak current control circuit operate in conjunction over the entire range of load conditions with the frequency control dominates at light load (or low power) conditions and the variable peak current control dominates at moderate to heavy load (or high power) conditions. The switching regulator transitions smoothly between frequency control and peak current control with continous loop gain throughout the transition region.