40results about How to "Fast frequency hopping" patented technology

A method and apparatus for generating a carrier frequency signal is disclosed. The method includes generating a first frequency signal; injecting a modulation signal at a first point of the two-point modulation architecture; 5 generating a second frequency signal from the modulation signal; introducing the second frequency signal by mixing the first frequency signal and the second frequency signal to generate a mixed frequency signal and outputting the carrier frequency signal selected from the mixed frequency signal.

The invention discloses a multistandard I / Q (In-Phase / Quadrature-Phase) carrier generating device based on a fractional frequency-dividing frequency synthesizer. The device comprises a three-order differential loop filter (10), a preset module (11), a full-differential quadrature voltage-controlled oscillator (12), a switch type bumper (13), a continuous two-dividing frequency divider module (14), a multimode frequency divider (15), a frequency and phase discriminator / charge pump (16), a nonvolatile memory (17) and a digital processor (18). By utilizing the invention, the frequency can continuously cover the range from 0.7GHz to 6GHz by reasonable frequency distribution, and the rapid frequency hopping is realized by presetting the frequency by the digital processor with strong function.

The invention discloses a self-accelerating locked phase-locked loop, which comprises a frequency and phase detector, a charge pump, a low-pass filter, a voltage-controlled oscillator, a frequency divider, a rectifier, a filter, and a bandwidth control circuit. The frequency and phase detector, the charge pump, the low-pass filter, and the voltage-controlled oscillator are connected in sequence, and the output of the voltage-controlled oscillator is fed back to one input terminal of the frequency and phase detector through the frequency divider, and the other of the frequency and phase detector One input terminal is connected to a reference frequency source. The output terminal of the frequency and phase detector is also connected to the input terminal of the rectifier, and the rectifier, filter, and bandwidth control circuit are connected in sequence, and the bandwidth control circuit is used to generate a control word signal proportional to the output signal of the frequency and phase detector and input it to the low The pass filter controls the number of capacitors connected in the parallel capacitor array of the low-pass filter to control the bandwidth, so as to realize the accelerated locking of the phase-locked loop to the reference frequency.

The invention relates to a short-wave pre-and-post-selector, which comprises a digital control circuit, transmitting-receiving switching circuits, band switching circuits, frequency hopping filters, a decoder, a broadband low noise amplifier and a receiving protection circuit, wherein the digital control circuit is electrically connected with an external short-wave radio station control unit through a control interface; serial codes sent by the short-wave radio station control unit are received by the digital control circuit and converted into parallel tuning codes respectively used for controlling the frequency hopping filters, the band switching circuits and the transmitting-receiving switching circuits so as to realize transmission on carrier signals different in frequency point and rapidly perform switching on carrier frequencies of useful signals; the transmitting-receiving switching circuits comprise a first transmitting-receiving switching circuit, a second transmitting-receiving switching circuit, a third transmitting-receiving switching circuit and a fourth transmitting-receiving switching circuit; the band switching circuits comprise a first band switching circuit and a second band switching circuit; the frequency hopping filters comprise a first frequency hopping filter and a second frequency hopping filter. The short-wave pre-and-post-selector disclosed by the invention has the advantages of being reasonable in structure, stable and reliable to use, strong in anti-jamming capability, low in cost, simple to control, fast in frequency hopping speed, low in power consumption, small in bottom noise and the like.

The invention relates to a frequency-modulated continuous-wave radar based on a numerically controlled oscillator, and belongs to the technical field of integrated circuits. The frequency-modulated continuous-wave radar comprises a low noise amplifier, a mixer, an intermediate frequency amplifier, a filter, a signal processor, a power amplifier and a phase-locked loop, wherein the phase-locked loop comprises a digital control module, a numerically controlled oscillator, a phase discriminator and a low-pass filter. The frequency-modulated continuous-wave radar adopts an open-loop structure of the phase-locked loop composed of the numerically controlled oscillator and the like as a radar system signal source, effectively increases frequency scanning speed of the signal source, enables the frequency change time interval to reach nanosecond order, enhances system performance, and has the advantages of rapid signal source frequency change, high universality, simple structure, easy implementation, small unit size, high integratable density and the like, and is suitable for chip SOC.

The invention discloses a frequency generating device comprising: a base frequency generating circuit, used to generate a reference frequency; a frequency synthesis circuit, connected to the base frequency generation circuit, used to generate a corresponding synthesized frequency according to the configuration parameters of the reference frequency and the frequency synthesis circuit; Frequency; frequency extraction circuit, connected with frequency synthesis circuit, used to extract high-order image frequency from synthesized frequency; phase-locked loop circuit, connected with frequency extraction circuit, used for configuration parameters according to high-order image frequency and phase-locked loop circuit Output the corresponding output frequency. The invention also discloses a frequency generating method. Through the above method, the present invention can reduce phase noise and spurs while realizing fast frequency hopping and high frequency resolution.