46 results about "Comb generator" patented technology

A jammer for jamming communications in a communications system where the communications system operates with digital bursts having burst periods measured in time and occurring in a communication frequency band such as GSM having a transmit band and a receive band. The jammer includes a tone comb generator for providing repetitions of jamming signals for the communication frequency band where the jamming signals have jamming signal intervals providing frequency separation between the jamming signals. The jamming signals are generated with a dwell time substantially less than a burst period for the communications system. The jamming signals are generated concurrently for the transmit band and the receive band and are transmitted as RF jamming signals to jam communications for mobile stations.

A vectorial network analyzer including n test ports. With the connection of several different calibration standards to the test ports, several calibration measurements are implemented. For the calibration, different measurements are implemented. Initially, in n calibration measurements, a comb-generator signal is supplied via a direct connection successively to all n test ports. Using a measuring point at the output of the comb generator and the measuring point associated with the respective test port, phase measurements are implemented at all of the frequencies forming the comb-generator signal. A frequency-dependent phase offset is determined from the phase measurements. Moreover, in at least one measurement, all n test ports are terminated successively in each case using known, input impedances, identical within one measurement, of arbitrary transmission properties, wherein successively, all n test ports are excited using a transmission oscillator successively with all frequencies of the comb-generator signal.

A scheme for reconstructing multiband signals that occupy a small part of a given broad frequency range under the constraint of a small number of sampling channels. The multirate sampling scheme (MRS) entails gathering samples at several different rates whose sum is significantly lower than the Nyquist sampling rate. The number of channels does not depend on any characteristics of a signal. The reconstruction method may or may not rely on the synchronization between different sampling channels. The scheme can be implemented easily with optical sampling systems. The optical pulses required for the under-sampling are generated by a combination of an electrical comb generator and an electro-absorption optical modulator

The invention discloses a dual-channel microwave frequency comb generator which comprises a signal generator module, an optoelectronic feedback module and a control module. The signal generator module comprises a 850nm vertical cavity surface emitting laser VCSEL, a temperature controller, a current controller, an aspheric lens, an isolator, a half-wave piece and a polarization beam splitter. The optoelectronic feedback module comprises a photodetector, a power amplifier, a power attenuator and a radio frequency bias. The control module comprises a data acquisition card which is connected with the signal generator module and the optoelectronic feedback module and a computer, and is used for adjusting external parameters of a laser system and acquiring data. The microwave frequency comb generator uses the VCSEL as a core device, has the advantages of small whole system volume, easy integration and low cost, and can acquire dual-channel microwave frequency comb signals.

A frequency comb generator fabricated on a chip with elimination of a disadvantageous reflow process, includes an ultra-high Q disk resonator having a waveguide that is a part of a wedge structure fabricated from a silicon dioxide layer of the chip. The disk resonator allows generation of a frequency comb with a mode spacing as low as 2.6 GHz and up to 220 GHz. A surface-loss-limited behavior of the disk resonator decouples a strong dependence of pumping threshold on repetition rate.

The invention discloses an active resonant cavity based self-similarity ultrashort pulse amplification system and a working method therefor. The self-similarity ultrashort pulse amplification system is characterized by comprising an optical frequency comb-shaped generator, a pre-chirping management apparatus, an active optical resonant cavity and a dispersion compensation apparatus that are connected in sequence, wherein the active optical resonant cavity is also connected with an electronic control circuit and a pump laser. The active resonant cavity based self-similarity ultrashort pulse amplification system has the advantages that an outer cavity enhancement technique is adopted, so that the self-similarity amplification for the ultrashort pulse is realized by using solid gain mediums, and the gain narrowing is overcome; the nonlinear widening of spectrum in the amplification process is realized, the pulse contract ratio is improved, and the problems of unstable modes, self-focusing and the like existing in the high-power amplification process of an optical fiber amplifier are effectively restrained; and the self-similarity ultrashort pulse amplification system is used as a reliable scientific research tool for researching high-field laser physics and non-linear optics.

An optical comb generator includes frequency-shifting elements of a particular type that we refer to as a “frequency mirror.” A frequency mirror mixes input light at a signal frequency and a reference frequency to produce output light at a third frequency that lies in contraposition to the signal frequency relative to the reference frequency. The comb generator includes at least two frequency mirrors, having respective reference frequencies F₁ and F₂. At least some of the power of a light beam is shifted by the first frequency mirror from an input frequency to a frequency that lies in contraposition thereto relative to F₁, and then light at the shifted frequency is shifted to yet a new frequency by the second frequency mirror. The resulting twice-shifted frequency lies in contraposition to the once-shifted frequency, relative to F₂. The result is that a difference of 2(F₂−F₁) separates the twice-shifted frequency from the input frequency. This process is repeatable to generate a comb of equally spaced, shifted frequencies. In specific embodiments of the invention, the frequency mirror is a periodically poled lithium niobate (PPLN) device pumped by laser radiation at the pertinent reference frequency.

A variable frequency synthesizer and method of outputting the variable frequency is disclosed. The synthesizer comprises a first reference frequency, a direct digital synthesizer (DDS) receiving the first reference frequency and outputting a tuned frequency, a variable frequency comb generator receiving the tuned frequency and outputting a variable frequency comb comprised of a plurality of comb lines, a mixer receiving the variable frequency comb and a signal from an oscillator and outputting an intermediate frequency, a phase lock loop (PLL) receiving a second reference frequency and the intermediate frequency and outputting a phase lock signal, and the oscillator receiving the phase lock signal and outputting a variable synthesized frequency.

An optical comb generator for generating multiple optical wavelengths from a single source simultaneously for many optical channels on a semiconductor substrate. The comb generator provides narrow channel spacing using chirped Bragg grating with uniformly spaced grating pitches but with tapered waveguide to facilitate the fabrication process and generate laser comb channels with uniform line widths across all channels. The laser comb generator facilitates monolithic integration of many photonic integrated circuit elements.

The invention discloses a microwave frequency source component with low phase noise and high spurious suppression and a usage method thereof. The component comprises a crystal oscillator 1, a power splitter 2, a phase discriminator A3, a loop filter A4, a voltage controlled oscillator A5, a coupler A6, a filter A7, an amplifier A8, a filter B10, a filter C12, a phase discriminator B13, a loop filter B14, a voltage controlled oscillator B15, a coupler B16, an amplifier B17, a filter D18, a mixer 9 and a comb generator 11. The microwave frequency source component has the advantage of easiness inimplementation. A mixer phase-locked loop design technology is adopted, mixing processing is placed in a phase-locked loop, and feedback frequency is reduced by mixing, so that phase noise is reduced; mixing spuriousness is filtered by the phase-locked loop filter; and the microwave frequency source with low phase noise and high spurious suppression can be realized.

The invention provides a method for automatically acquiring YIG tuned filter compensation data and specifically relates to the technical field of signal analyzer dynamic non-linear compensation data acquisition. The method for automatically acquiring YIG tuned filter compensation data is applied to production debugging and calibration of signal analyzers and can achieve high-speed and high-precision linear tuning of a YIG tuned filter. In a production debugging or calibration process, a comb generator embedded in the front end of a radio frequency channel of a signal analyzer provides inspection input signals as a signal source. When YIG filter tuning is performed under a linear voltage or linear current (main tuning drive) , lag offsets vary with tuning frequency points, so that different comb wave signals with the same power do not have the same testing power after passing the a YIG filter. Proper compensation drive is provided for different tuning frequency points by invoking compensation data, so that a transient position of the YIG filter in a dynamic tuning process is consistent with that in static tuning and signal power testing is not influenced by a tuning process of the YIG filter.

An integrated electro-optic frequency comb generator based on ultralow loss integrated, e.g. thin-film lithium niobate, platform, which enables low power consumption comb generation spanning over a wider range of optical frequencies. The comb generator includes an intensity modulator, and at least one phase modulator, which provides a powerful technique to generate a broad high power comb, without using an optical resonator. A compact integrated electro-optic modulator based frequency comb generator, provides the benefits of integrated, e.g. lithium niobate, platform including low waveguide loss, high electro-optic modulation efficiency, small bending radius and flexible microwave design.

The present invention provides a method and device for determining the sideband ratio of a superconducting mixer using a comb generator. The method includes the steps of: (a) tentatively adjusting the sideband ratio of a mixer for calibration of an output of the comb generator; (b) determining the signal intensity of a pseudo-celestial signal oscillator for calibration of the output of the comb generator; (c) repeating the steps (a) and (b) to derive the relation between the sideband radio of the mixer for the comb-generator output calibration and the intensity of a pseudo-celestial signal; (d) calibrating the output of the comb generator; and (e) obtaining the sideband ratio of the mixer to be measured.

The current comb generator periodically applies current spikes to a power supply signal in the time domain to produce a series of current spikes at different frequencies in the frequency domain.

System and methods for the sampling of an optical signal by generating a plurality of copies of the spectrum of the said optical signal including at least one sampling block for the convolution between the optical input spectrum and an optical comb; wherein the said sampling block includes a modulator, and a bias voltage generator, the said sampling block is driven by an electrical comb generator and a phase shifter, the said electrical comb generator being configured to generate a number of N lines, with N from one to infinity, in the radio frequency domain, equally spaced in frequency and locked in phase, the said modulator being configured to generate a plurality of 2N+1 copies of the input spectrum from (i) the signal spectrum and (ii) a number of N lines provided by the said electrical comb generator.

A multi-tone multi-band tunable millimeter-wave synthesizer is provided. In some embodiments, the multi-tone multi-band tunable millimeter-wave synthesizer is configured to simultaneously generate multiple frequency tones for space-borne beacon transmitter for atmospheric radio wave propagation studies. The apparatus includes a comb generator, which puts out evenly spaced harmonic frequencies of the input signal, which are coherent, tunable, and the number of tones or combs is scalable over a wide range of frequencies. These harmonics or tones are amplified to the power level needed for radio wave propagation studies. The amplified signals are transmitted as beacon signals from a satellite to a ground receiving station.