16results about How to "Improved Gain Flatness" patented technology

The invention discloses a radio frequency transceiver gain flatness adaptive calibration circuit and method, and relates to the technical field of radio frequency circuits. According to the invention, the gain flatness self-adaptive calibration circuit is introduced into the radio frequency receiving or transmitting channel, so that after the circuit is manufactured, the gain flatness of the radio frequency channel can be automatically detected and calibrated, and the adverse effects of process deviation, power supply voltage change and temperature fluctuation (PVT) on the gain flatness of the radio frequency receiving or transmitting channel are improved.

The invention provides a low-noise amplifier and a radio frequency front-end module, and the low-noise amplifier comprises an input matching circuit, a first-stage power amplification circuit, an inter-stage matching circuit, a second-stage power amplification circuit and an output matching circuit. The inter-stage matching circuit comprises a first inductor, a second inductor and a first capacitor; the second-stage power amplification circuit is of a cascode structure; and the output matching circuit comprises a third inductor and a fourth inductor which are coupled with each other. According to the low-noise amplifier, the high-frequency gain, the in-band gain flatness, the isolation degree, the stability and the output matching bandwidth of the low-noise amplifier can be improved.

A variable-gain multistage broadband low-noise amplifier comprises N (N > = 2) stages of amplifying circuits, the first stage of amplifying circuit and the second stage of amplifying circuit are connected through a first inter-stage matching circuit, a main circuit switch and an inter-stage matching circuit are sequentially connected between the subsequent stages of amplifying circuits in series, the input end is connected with an input matching circuit in series to be connected to the first stage of amplifying circuit, and the second stage of amplifying circuit is connected with a second stage of amplifying circuit. The Nth-stage amplification circuit is connected in series with a main switch and an output matching circuit in sequence to a signal output end; from the second stage, each stage of amplifying circuit and the main switch are integrally connected with a bypass switch in parallel; a source degeneration inductance scheme is adopted for input matching, and the noise performance is optimized; the overall gain flatness is improved through inter-stage matching; a multi-stage LC structure is adopted for output matching, and broadband matching in different gain modes is achieved; according to the invention, control of each switch is realized through logic level signals, switching of multiple gain modes is realized, the designed bandwidth reaches more than 10GHz, and the overall gain flatness and the noise coefficient in different gain modes are kept consistent.

An embodiment of the present disclosure provides a signal amplification circuit and an electronic device, wherein the signal amplification circuit comprises: a first signal input terminal of a first operational amplifier is connected to one terminal of a first coupling circuit, and a first differential signal of a signal to be amplified is input to the other terminal of the first coupling circuit; a first signal input terminal of a second operational amplifier is connected to one terminal of a second coupling circuit, and a second differential signal of a signal to be amplified is input to the other terminal of the second coupling circuit; an output terminal of the second operational amplifier is respectively connected to a corresponding signal input terminal of a third operational amplifier; wherein the second signal input terminal of the first operational amplifier and the second signal input terminal of the second operational amplifier are respectively connected to a digital-to-analog converter via a voltage divider circuit; and an output terminal of the third operational amplifier is connected to the second signal input terminals of the first operational amplifier and the second operational amplifier via a third feedback network.

The present invention is applicable to the field of electronic circuit technology, and provides an amplifier and a radio frequency integrated circuit, wherein the amplifier comprises: an amplifying unit, a first biasing unit, a second biasing unit and a first feedback unit; wherein the amplifying unit comprises a first field effect transistor and a second field effect transistor; the first field effect transistor and the second field effect transistor are connected in series; the first biasing unit provides a bias voltage for the first field effect transistor, and the second biasing unit provides a bias voltage for the second field effect transistor; the first feedback unit provides a feedback voltage signal for the first field effect transistor; the amplifying unit of the present invention adopts a common source and common gate structure, and at the same time introduces a feedback signal through the first feedback unit, so that the amplifier has low noise and has good gain flatness in a wider frequency band, and at the same time meets the requirements of low noise, wide frequency band and high gain.

The invention provides a numerical analysis zero point reconfigurable method for designing a sub-array directional diagram, which comprises the following steps of: 1, designing a 40% relative bandwidth sub-array, and respectively extracting two orthogonal plane directional diagrams of a highest frequency band, a center frequency band and a lowest frequency band; step 2, performing numerical analysis on the sub-array radiation pattern, extracting influence parameters of the zero position and the null depth of the pattern, and adjusting corresponding parameters for designing the sub-array pattern, so that the zero position of the sub-array pattern needs to correspond to the array factor grating lobe position, and the zero position of the sub-array pattern needs to correspond to the array factor grating lobe position; the zero point of the sub-array directional diagram and the array factor grating lobe can be mutually counteracted by the null depth; and step 3, determining a structural feed network of the phase shifter capable of realizing 0-degree and 68-degree phase adjustability, wherein the structural feed network is used for realizing independent regulation and control on the phase difference of the two units in the subarray. According to the invention, + / -30-degree grating lobe-free scanning of the array with the array element center-to-center distance of 1 lambda can be realized, and good gain flatness can be maintained.

The invention provides a high-linearity amplifier with a filtering function. The high-linearity amplifier comprises an input matching network, a bias network A, a bias network B, a feedback network, a filtering network, an amplifying circuit and an output matching network, a Cascode circuit structure is adopted to form an amplifying circuit, and gain flatness and good input and output matching are guaranteed through an RC feedback network. Transistor bias voltage which slightly fluctuates along with temperature change is provided for the amplifier through the bias network A and the bias network B, so that stability of static current of the whole amplifier along with temperature change is guaranteed. The low-pass filtering function is achieved by introducing the filtering network into the amplifier, high-frequency harmonic and clutter suppression of the amplifier is improved, meanwhile, the linearity of an amplification circuit is improved by optimizing the structures of the bias network A, the bias network B and the filtering network, and the design flexibility of the amplifier is improved.

The present application relates to the field of optical communication technology, in particular to a kind of optical fiber dispersion compensation adaptive amplification method and device thereof, comprising: obtaining the dispersion compensation value of dispersion compensation module;According to the total gain of dispersion compensation module, the dispersion compensation value is redistributed to multiple fiber amplifiers;According to the gain of each fiber amplifier after redistribution, the first expected attenuation value of the variable optical attenuator arranged in each fiber amplifier is calculated respectively, and the attenuation compensation amount of each variable optical attenuator is calculated according to the dispersion compensation value;According to the first expected attenuation value and attenuation compensation amount, the second expected attenuation value is calculated;According to the probe power of the first input end of variable optical attenuator and the probe power of the first output end, the actual attenuation value is calculated;Actual attenuation value and second expected attenuation value are compared, if consistent, then stop adjusting variable optical attenuator;Otherwise, continue to adjust.

The application discloses a wide-angle frequency scanning antenna based on a dual-band coupling filter, comprising a power divider module, a dual-band filter module and an antenna radiation unit. The power divider module is used for power distribution of an input signal; the dual-band filter module is used for phase modulation of the output signal of the power divider; and the antenna radiation unit is used for signal radiation of the dual-band. The application adopts the dual-band filter to modulate the signal phase, realizes two groups of different phase distributions changing with frequency in the specified two frequency bands respectively, and covers different angle ranges in the positive and negative directions respectively, so that the wide-angle scanning from-60° to 60° is realized finally. The dual-band design reduces the design pressure of the single-band scheme. With the flexible bandwidth design function of the filter, the frequency scanning antenna can be customized according to the actual demand. The wide-angle frequency scanning antenna realized by the application has the advantages of large scanning range, small scanning gain fluctuation and customizable frequency band range.

The invention discloses a high-gain flatness miniaturized broadband electric field probe based on a three-stage transition structure. The three-stage transition structure is composed of a symmetrical arc transition structure of a coupling part, a symmetrical bevel edge transition structure of a transmission part and a gradually-changed transition improved coplanar waveguide of an output part. The improved induction tip formed by the symmetrical arc transition structure and the circular detection structure can effectively increase the coupling capacitance between the electric field probe and a to-be-detected piece and improve the transmission gain of the electric field probe at a low frequency band. The symmetrical bevel edge transition structure can enable expected energy of an induction signal to be transmitted to the output part in a more concentrated manner, restrain resonance, ringing-like ripples and surge ripples of the electric field probe in a middle-high frequency band, and improve gain flatness of the middle-high frequency band. The gradual transition improved coplanar waveguide ensures that the characteristic impedance of the contact part of the central conductor and the miniature coaxial connector is 50 ohms.

The invention discloses an LNA (low noise amplifier) with high gain flatness and multi-band adjustment for aerospace information acquisition. Comprising a first low-noise amplification module, a first radio frequency switch, a first filtering module, a second radio frequency switch, a first adjustable attenuation module, a second low-noise amplification module, a second adjustable attenuation module, a third low-noise amplification module, a third radio frequency switch, a second filtering module and a fourth radio frequency switch which are connected in sequence. Each of the first filtering module and the second filtering module comprises a plurality of signal paths with different frequency response characteristics; a signal path of the first filtering module comprises an equalizer and a band-pass filter, and a signal path of the second filtering module comprises a band-pass filter; and the first radio frequency switch, the second radio frequency switch, the third radio frequency switch and the fourth radio frequency switch are used for selecting signal paths, so that the technical problems that in the prior art, extremely low noise and high and flat power gain are difficult to maintain in a wide frequency band, and switching in different frequency bands cannot be flexible are solved.

The utility model relates to the technical field of optical detection, in particular to an optical acquisition circuit, an optical time domain reflectometer and a laser radar. Comprising a power supply module, a filtering module, a current-limiting module and an acquisition module. The voltage input end of the filtering module is connected with the voltage output end of the power supply module, the voltage input end of the current limiting module is connected with the voltage output end of the filtering module, and the voltage input end of the acquisition module is connected with the voltage output end of the current limiting module. The photoelectric conversion module is used for converting photoelectric signals and amplifying converted electric signals according to bias voltage; by adding the filtering module at the voltage input end of the current limiting module, the current limiting module can be used for protecting the acquisition module, and meanwhile, the filtering module can be used for filtering high-frequency noise, so that the problem that the acquisition module is easy to damage when the input end is high-power light is avoided; and the gain flatness of the light acquisition circuit can be effectively improved, the linearity of the acquired signal is improved, and the signal-to-noise ratio of the acquired signal is improved.

The invention belongs to the technical field of optical fiber communication, and particularly discloses an annular pump cavity multiplexing module and a broadband optical fiber amplification system thereof, specifically, a pump supply unit in the annular pump cavity multiplexing module provides a plurality of wave bands of pump light required by each optical fiber amplification module; the pump light coupling unit controls the transmission direction of pump light and splits the pump light, one part of the pump light enters the pump light circulating unit, and the other part of the pump light enters the pump distribution unit; the pumping distribution unit provides pumping light for each optical fiber amplification module according to wavelength and power; the pump light circulation unit compensates the absorption and loss of the pump light; and after the signal light of each optical fiber amplification module is amplified by the gain optical fiber, the pump light recovery unit recovers the residual pump light to the pump light coupling unit so as to be reused by the system. According to the broadband optical fiber amplifier, the cyclic utilization rate of the pump light is increased, fluctuation of the power of the pump light is reduced, and high-gain and low-noise integrated flat amplification of the broadband optical fiber amplifier can be achieved.

The invention discloses a radio-frequency power supply circuit, a radio-frequency power supply circuit system and a radio-frequency power supply, and belongs to the technical field of radio-frequency power supply circuit design, the radio-frequency power supply circuit comprises a driving circuit, the driving circuit comprises an input end and at least two broadband power amplifiers, and the input end is connected with the adjacent broadband power amplifiers through a power supply. Corresponding pi-attenuation circuits are arranged between any two adjacent broadband power amplifiers, each pi-attenuation circuit comprises three resistors, the second ends of the two resistors are grounded, and the first ends of the two resistors are connected with the first end and the second end of the third resistor respectively. According to the radio frequency power supply circuit, self-excitation oscillation of the driving circuit can be effectively suppressed, so that the quiescent current of the radio frequency power supply is stabilized, the gain flatness of the radio frequency power supply is improved, and the effect of improving the stability of the radio frequency power supply is achieved.

This invention discloses a high-bandwidth, notch-free hybrid magnetocurrent sensor circuit, comprising a low-frequency path, a high-frequency path, a differential amplifier, a compensation path, and a dual-to-single converter. The low-frequency path utilizes a Hall effect sensor and auxiliary bias circuitry to detect the low-frequency component of the current, and simultaneously suppresses sensitivity drift and common-mode drift by replicating a negative temperature coefficient voltage. In the high-frequency path, the integrator consists of two paths with the same gain-bandwidth product but different low-frequency gains, and gain flatness is improved through compensation technology. The servo loop employs active capacitor amplification technology, using small-area resistors and capacitors to achieve ultra-low-frequency poles. The outputs of the high- and low-frequency paths are combined via a differential amplifier and then pass through a subtractor and a high-pass filter to form a compensation path for eliminating chopper ripple. Finally, the signals are converged in the dual-to-single converter to obtain a notch-free broadband output. This invention simultaneously solves problems such as chopper notch, gain unevenness caused by pole-zero mismatch, and the use of large-area passive components.

The utility model provides a circularly polarized ultra-wideband microstrip patch antenna based on a metasurface. The circularly polarized ultra-wideband microstrip patch antenna based on the metasurface comprises a dielectric substrate I, low-loss dielectric foam, a dielectric substrate II, a metal ground layer, the metasurface, a slotted circular patch, a metalized through hole and a feed port, the slotted circular patch is arranged on the upper surface of the dielectric substrate I in parallel, the low-loss dielectric foam is arranged between the dielectric substrate I and the dielectric substrate II, and the metasurface is arranged on the upper surface of the dielectric substrate II in parallel; the metal ground layer is located on the lower surface of the first dielectric substrate, four rectangular grooves are etched in the metal ground layer, the metalized through hole is used for connecting the slotted circular patch and the metal ground layer, and the metalized through hole forms a feed port through a coaxial line. According to the ultra-wideband circularly polarized antenna, ultra-wideband circularly polarized radiation is realized through a simple planar structure, and the ultra-wideband circularly polarized antenna has the characteristics of low profile and small size, and is convenient for further processing and integration.