37results about How to "Fast frequency conversion" patented technology

The invention provides a noise waveform signal generating device and belongs to the technical field of signal generators. The invention aims to provide the noise waveform signal generating device which can generate conventional signals and noise signals and has output signals with stable stability, wide range and high resolution ratio. With the adoption of the technical scheme, the noise waveform signal generating device comprises a single chip microcomputer, a D / A (Digital / Analogue) conversion module and a signal processing module; a signal output end of the single chip microcomputer is connected with the D / A conversion module; a signal output end of the D / A conversion module is connected with signal input ends a1 and a2 of the signal processing module; and signal output ends of the signal processing module are b1 and b2; and the single chip microcomputer is further connected with a keyboard and a display screen. The noise waveform signal generating device is applied to relevant fields of automatic control, scientific tests, electronic circuits and the like.

The invention discloses a method and a system of parallel emission of multichannel carrier light signals. The system drives a direct numerical frequency synthesizer chip to generate a square signal through intellectualized control of a control terminal, wherein frequency and phase positions of the square signal are continuous and controllable, and the system outputs the square signal to control a light emitting diode (LED) to flicker in fixed frequency. During the working process of the LED, an LED drive module and an optical feedback module act together and enable the LED to output carrier light signals which are stable in power in long power mode, the optical feedback module feeds received LED power instability fluctuation back by using a photovoltaic conversion diode and restrains power fluctuation by being combined with the LED drive module, and furthermore the multichannel carrier light signals which are controllable in frequency and phase position are generated by arranging a multichannel square signal generator and an LED module in parallel. The whole system is intelligent and controllable, high in integration level, low in power consumption, stable and reliable in work, and wide in application scope, can be extended in multiple channels, and is an integrated carrier light generating system.

The invention discloses high-stability combined region time service frequency generation equipment and aims to provide time service frequency generation equipment with high reliability, high length stability and a wide application range. The invention adopts the technical scheme that a receiving switching unit inputs two paths of selected satellite second signals from different sources into a locking unit to carry out frequency locking, two paths of phase-locked standard frequency signals generated by the locking unit and are respectively output to a signal processing unit A and a signal processing unit B; one path of satellite second signal is also used for carrying out frequency correction on a rubidium clock connected in parallel between a three-selection two-open device and a first analog phase-locked loop PLL_A, and one path of standard frequency signal is generated and transmitted to a signal processing unit C; and the signal processing units carry out signal shaping, amplification, shunting and coding on three paths of standard frequency signals from different sources, the obtained signals are subjected to frequency division, output to a far-end time service unit and are converted into optical signals by an optical-electrical converter, and the optical signals are transmitted to an equipment machine room by one or multiple paths of optical fibers and then are converted into electric signals, and the electric signals are transmitted by an antenna so as to complete a clock time service of a receiving end.

The invention discloses a quick acquiring method for multi-frequency-point bioelectrical impedance. A multi-frequency-point composite excitation source Vin is realized based on a DDS (direct digital synthesizer) principle by means of FPGA (field-programmable gate array) programming, the composite excitation source Vin is loaded onto reference resistance Rref and to-be-tested organism electric impedance Zx simultaneously, corresponding amplitudes Ampref and Ampx and phase angles Degref and Degx of the Vref and Vx on frequency points can be acquired accurately by reasonably selecting sampling frequency fs and points N of DFT (digital Fourier transform) and by only performing DFT on the Vref and Vx on the several needed frequency points, and further amplitudes of the to-be-tested organism electric impedance Zx on the frequency points are acquired. The quick acquiring method has the advantages of high impedance acquisition accuracy, small operation amount, high anti-jamming capability, short scanning time and the like.

The invention relates to a novel noise signal generator, which belongs to the technical field of a signal generator and aims at solving the technical problems to provide the novel noise signal generator with the advantages that conventional signals and noise signals can be generated, in addition, the frequency of output signals is stable, the range is wide, and the resolution is high. The novel noise signal generator has the technical scheme that the novel noise signal generator comprises a signal generating circuit and a signal processing circuit, wherein the signal output ends a1 and a2 of the signal generating circuit are respectively connected with the signal input ends b1 and b2 of the signal processing circuit, and the signal output ends of the signal processing circuit are c1 and c2. The novel noise signal generator is applied to the relevant fields of automatic control, scientific tests, electronic circuits and the like.

The invention discloses an output device of different sources of frequencies, and aims at providing the frequency source device of fast switching, high reliability and accuracy and high length stability. Two paths of satellite second signals, of different sources, are processed by a locking unit to generate two paths of phase-locked standard frequency signals, the two paths of standard frequency signals are output to an amplification output unit A and an amplification output unit B, one path of the signals is provided for a rubidium clock connected, in parallel, between a two-of-three switch and a first analog phase-locked loop PLL_A for frequency calibration, a rubidium clock clean up unit generates one path of standard frequency signals and transmits the path of signals to an amplification output unit c, two clean up oscillators in parallel connection lock signals of themselves in signals which take rubidium clock frequency signals as reference, output signals of the rubidium clock clean up is transmitted to the amplification output unit c, and thus, three paths of standard frequency signals of different sources are output.

The invention relates to a calibration system of a servo equivalent device. The system comprises a bus measurement and control host, a signal adaptive box, and an ultra-low frequency signal generator;the bus measurement and control host comprises a bus controller module, a digital multimeter module, an oscilloscope module and a data communication module; the bus controller module is connected with input ends of the signal adaptive box and the ultra-low frequency signal generator through the data communication module; an output end of the ultra-low frequency signal generator is connected withthe input end of the signal adaptive box, the digital multimeter module and the oscilloscope module are connected with the input end of the signal adaptive box, and the output end of the signal adaptive box is connected with a telemetering interface and a control interface of the servo equivalent device. The calibration system of the servo equivalent device provided by the invention constructs a novel ultra-low frequency response analyzer, realizes the automatic calibration of the servo unit equivalent device, and simplifies the calibration operation, thereby avoiding the importing of the artificial error.

The present invention relates to a kind of S-band segmented multi-ary system chirp modulation wireless communication system, comprising a transmitter and a receiver, and the receiver receives a transmission signal from the transmitter; the transmitter includes an FPGA, a system clock, a high-speed DDS unit, a radio frequency Local oscillator unit, mixer, power amplifier, antenna; FPGA drives high-speed DDS unit to generate chirp coded signal, RF local oscillator unit generates local oscillator signal, chirp coded signal and local oscillator signal are mixed by mixer, and mixed Frequency processing moves the spectrum of the chirp coded signal to the 2-4GHz frequency band, and sends it to the power amplifier for amplification after frequency mixing processing, and the amplified signal is transmitted by the antenna; FPGA, according to the user-defined data requirements, performs coding and selects the transmission bandwidth and frequency band interval; user-defined data includes digital system, encoding bandwidth, encoding segmentation interval and transmitting frequency band; system clock provides clock frequency for high-speed DDS unit and FPGA.