264results about "Time pulses" patented technology

The invention discloses a method and corresponding device for taming crystal oscillation frequency of a time-keeping device, which comprises the following steps of: step 1, acquiring the standard time pulse A that is located and output by a navigation satellite; step 2, acquiring the standard time pulse B output by device crystal oscillation fractional frequency; step 3, measuring the clock difference between the standard time pulse A and the standard time pulse B; and step 4, if clock difference exists between A and B, adjusting the crystal oscillation frequency of the device to make the clock difference be in the allowed scope. For the time-keeping equipment with pressure control and temperature compensating crystal oscillation or pressure control crystal oscillation, the frequency deviation of the corrected crystal oscillation can be detected in real time by the method provided by the invention to eliminate the time-keeping error caused by crystal oscillation frequency deviation and avoid accumulation of error. Therefore, the invention is suitable for various satellite navigation systems, such as GPS, Beidou first generation navigation satellite, Beidou second generation navigation satellite, GLONASS, GALILEO and other satellite navigation systems.

A chronometric identification and location tag for an animal, such as a dog, that incorporates a variety of detection and sensing functions as well as communication capacities. Assembled in a compact form that allows ready transport on a trainable animal, such as a dog, the chronometer identification and location tag enables the location of the associated animal, as well as the transmission and reception of information and data. Specific embodiments include the use of GPS to provide location data, as well as an alternative location system using temporary or permanent antenna installations. Hazardous material, visual, and acoustic detectors and other sensors and/or generators may be used in conjunction with transmission facilities for providing data regarding the animal's environment. Information and signals may be transmitted to the central controller by a receiver and a speaker can provide for audio signaling to the animal or others close to the animal in an audible range of the speaker.

A transmitted time signal carries time information encoded bit-wise by signal variations in a succession of constant duration time frames, with at least one bit in each time frame. A signal quality is determined and allocated to a respective bit, e.g. depending on the extent of deviation of an actual duration from prescribed durations of a signal variation representing the bit. Thus, a respective signal quality may be allocated to a respective decoded data bit per time frame. Successive data bits can be categorized as interference-free or interference-burdened, and a signal quality of the received time signal can alternatively be determined from the number or ratio of the interference-free bits and the interference-burdened bits. A radio-controlled clock circuit includes a receiving circuit, a bit value decoding arrangement and a signal quality evaluating arrangement.

A method and apparatus to correct a periodic signal, such as a frequency reference, based upon another frequency reference. A lower accuracy frequency signal generator (104) provides an uncorrected frequency reference signal (122) to a frequency corrector (106). Frequency corrector (106) counts cycles of a frequency reference signal (124), as generated by a higher accuracy reference generator (102) for a time period derived from the uncorrected frequency signal. Based upon the cycles counted, pulses are added or removed from the uncorrected frequency signal (122) to produce a corrected frequency signal (126). A ratio of pulses to be removed from the uncorrected frequency signal (122) is determined from the number of cycles counted and a counter arrangement is provided to automatically remove the required ratio of pulses from the uncorrected frequency signal (122).

Methods and systems for providing accurate time-keeping on battery-powered communication devices used in AMI systems, mesh networks, and multi-channel radio networks. One embodiment allows the use of low power (and low cost) crystals in battery-powered endpoints by periodically correcting the poor timing of these crystals using communications with a nearby, non-battery-powered device. Such communications allow the battery-powered devices to align their timing with that of their non-battery neighbors, among other things.

The present invention is a novel method and apparatus for implementing a high-precision timer utilizing a non-optimal oscillator and a high-speed oscillator wherein only one oscillator is enabled at a given moment in time. The high-precision timer method and apparatus comprises a timer and an error-correction technique. In one embodiment, the timer of the present invention is constructed from a high-speed oscillator and a low-speed non-optimal oscillator. The timer operates from the high-speed oscillator during on-the-air modes of operation and from the low-speed non-optimal oscillator during sleep modes of operation. The present inventive method corrects errors that are introduced by the non-optimal oscillator and a swallow counter. The errors are corrected using an error-correction technique having two steps: an error-determination step and an error-correction step. In the preferred embodiment of the error-determination step, a total error for a time interval is determined by performing the following steps: (1) calculating an individual error that occurs at each pulse; (2) multiplying the individual error by the number of pulses occurring during the time interval; and (3) adjusting for a non-optimal counter. Once an error has been determined, the error-correction step adjusts a clock counter accordingly. Depending upon the error-correction technique used, the error-correction step can correct the total error at one of several locations within a timer counter chain that is used to practice the present invention. The implementation of the present invention allows a straightforward realization of multiple timers.

The invention relates to a high-precision GPS (Global Positioning System) 1pps (1 Pulse Per Second) timer of a spacecraft. Time is recorded by a system timer according to relevant pulse signals with a hardware latch technology. For the first time, a pulse receiving module, a timer latch control module, a register block, a timing module and a timer are all utilized for timing of the pulse signals. Signal timing is realized by a hardware latch mode instead of a traditional software interrupt way. A time error is only limited to a hardware transmission error, and the hardware transmission error can be neglected in comparison to interrupt response time. The accuracy and the stability of the utilization of the GPS 1pps signal in timing are largely improved, and the requirement of the spacecraft on high precision signal timing is met.

The invention relates to an intelligent ammeter clock calibration method aims at utilizing conventional resources of a single chip microcomputer to realize wide-range high-precision error correction. The technical scheme includes: a, measuring frequency deviation values of different temperature points, and simulating a temperature-frequency deviation curve; b, determining a minimum correction value of coarse tuning, and utilizing a formula obtained in step a to calculate out frequency deviation at current temperature as a compensation value; c, if the compensation value is smaller than the minimum correction value of the coarse tuning, executing step g, or executing step d; d, if M is 2, 3, 4 or 5, executing step e, or executing step f; e, using an internal pulse counter to perform pulse counting to signals output by a crystal oscillator, coarse tuning, and executing step g; f, performing frequency multiplication or frequency demultiplication to the signals output by the crystal oscillator to obtain a signal Ft; and g, arranging a controllable capacitor array at an output end of the crystal oscillator.

A vibration gyro sensor is provided which is capable of generating time information and detecting an angular velocity. A driving signal for driving a tuning fork piezoelectric vibrating reed is generated based on an excitation signal generated by an oscillation circuit. An angular velocity signal is obtained based on a detection signal generated by a detection electrode of the tuning fork piezoelectric vibration reed. The excitation signal generated by the oscillation circuit is input to a divider such that a timer clock signal is generated.

The invention relates to an adaptive time synchronization method based on temperature compensation, belonging to the technical field of wireless sensor networks. In consideration of the large influence of the environmental temperature on a clock crystal oscillator frequency, the method includes the following steps: firstly, a temperature-crystal oscillator frequency model is established by using the correlation between the clock drift and temperature, and nodes can compensate for the offset of a clock according to the temperature changes under the model to improve the accuracy of synchronization between the nodes; and secondly, in the case that the network delay is a Gaussian model, and in combination with the relevant theory of probability time synchronization, the nodes can compensate for the current time according to a maximum synchronization error allowed by the network and the accumulated clock offset, and estimate a corresponding resynchronization interval. According to the method, the nodes can reduce the energy consumption to the greatest extent on the basis of meeting the specific synchronization accuracy, and the network load can be reduced.

The present invention provides an oscillation circuit which enables a further decrease of power consumption. The oscillation circuit comprises a piezoelectric oscillator, such as a quartz oscillator, for generating voltage that oscillates at a natural frequency, an inverter for amplifying this oscillation voltage, a Schmitt trigger circuit for shaping the waveform of the output of the inverter and outputting oscillation output signals, and a constant current source which is connected to a power supply line from a battery and supplies current to the power supply of the inverter and the Schmitt trigger circuit.

An oscillator includes oscillator circuitry (8) including a transconductance stage (2) and a resonator (3). A comparator (10) produces first (CLK) and second (/CLK) clock signals which indicate the timing of positive and negative phases of a differential output signal (V_IN⁺-V_IN⁻) produced by the transconductance circuit in response to the resonator. A synchronous rectifier (14) converts the differential output signal to a current (I_RECT) in response to the first and second clock signals. A switched capacitor notch filter (15) filters the current in response to the first and second clock signals. A control current (I_CONTROL) which controls the transconductance of the transconductance circuit is generated in response to the notch filter. The resonator may be a MEMS resonator.

A method and a device for calibrating an interior clock generator installed inside a power monitoring unit of a rechargeable battery. The device includes an input pin for inputting an external clock signal from an exterior clock generator installed outside the power monitoring unit. A calibration timer control circuit is connected to the input pin. A register is connected to the calibration timer control circuit for outputting a start signal to activate the calibration timer control circuit. A counter and a timer are controlled by the calibration timer control circuit to be activated simultaneously therewith to count the outside clock signal and an internal clock signal generated from the interior clock generator, respectively. Such that the timer stops counting while the counter stops counting, a first count of the timer is compared to a second count of the counter to calibrate the interior clock generator.