40results about How to "Increase low frequency gain" patented technology

The invention relates to a high gain broadband dielectric lens Vivaldi antenna. The array antenna comprises a substrate, a radiation slot, a dielectric lens and a Chebychev tapered strip line feeder. According to the high gain broadband dielectric lens Vivaldi antenna, through changing the structural size of the dielectric lens, the fluctuation of antenna radiation impedance can be effectively improved so as to obtain better impedance matching, the transmission speed of an electromagnetic wave in the slot can be reduced according to the high dielectric constant of the lens, the current distribution on an antenna aperture is improved, thus a spherical wave is a nearly a plane wave, the antenna radiation efficiency is raised, and a higher antenna gain is obtained. According to a Chebychev tapered strip line, the impedance matching of the antenna can be improved further, and the working band is broadened. The array antenna in the invention has the characteristics of high gain and broad band and is suitable for a radiation unit of wideband array antennas of the field of mobile communication and a military radar.

The invention discloses a transconductance-enhanced recovery current folded MOS (metal oxide semiconductor) transistor cascade amplifier, belonging to the design field of analogue integrated circuits. The amplifier comprises a transconductance-enhanced input stage, an intermediate stage for amplifying a recovery current and a rail-to-rail output stage, wherein the transconductance-enhanced input stage is formed by four shunted PMOS (P-channel metal oxide semiconductor) transistors and four (two pairs of) PMOS transistors constituting negative resistance enhanced transconductance, and used forconverting input voltage signals into four paths of currents and multiplying transconductance of input tubes; the intermediate stage for amplifying the recovery current mainly comprises two low-voltage current mirrors and is used for realizing the amplification of the recovery current; and the rail-to-rail output stage mainly comprises two PMOS transistors and two NMOS (N-channel metal oxide semiconductor) transistors and is used for realizing the rail-to-rail output of signals. The amplifier is capable of improving the bandwidth capability by over two times under the condition of not increasing power consumption, greatly increases low-frequency gains and large-signal slew rate, improves phase margin and enhances performances of a circuit.

The invention is a high speed phase splitting circuit. In the circuit, a source follower is connected with a phase splitting amplifier which is connected with a lossy integrator; the source follower is used for carrying out level shift on the signal output by a transimpedance amplifier; the phase splitting amplifier is used for transforming the input single-ended signal into double-ended differential signal and amplifying the double-ended differential signal in a higher speed; two input ends of the lossy integrator are respectively connected with output ends of the phase splitting amplifier, and the common mode voltage difference of the phase splitting amplifier controls the output of the integrator; the output voltage of the integrator is connected on the reverse input end of the phase splitting amplifier, and the common mode voltage thereof changes with the common mode voltage of the input signal.

The invention discloses a balance antipodal Vivaldi antenna adopting unsymmetrical medium rejection and mixed grooving and relates to the field of antennas. While low cross polarization of a traditional balance antipodal Vivaldi antenna is kept as an advantage, the problem that due to asymmetry of the traditional balance antipodal Vivaldi antenna, a main lobe of the E face of the antenna deviates is solved. Each floor metal layer is attached to the lower surface of a medium substrate layer, a conductor metal layer is attached to the upper surface of the lower medium substrate layer, the conductor metal layer and the floor metal layers extend to the two sides respectively to form metal arms, the metal arms formed by the floor metal layers and the metal arm formed by the conductor metal layer are symmetrical in structure, the outer sides and the inner sides of the metal arms are of curve structures, the lower medium substrate layer located between the curve on the inner side of the conductor metal layer and the curve on the inner side of the lower floor metal layer is rejected, and the rejected lower medium substrate layer is provided with one more medium section compared with the curves on the inner sides of the floor metal layers. The balance antipodal Vivaldi antenna is used for working within the working frequency of 10-40 GHz.

The invention relates to a detection circuit for a magnet-hydro-dynamics (MHD) angular-rate sensor. The detection circuit is formed by function modules: a differential amplification module, a bandwidth expansion module and a band-pass filtering module and the like, and can control noise level of the sensor effectively, improve weak signal detection capability and expand work bandwidth. Besides, the detection circuit can achieve the effect of suppressing zero position bias and zero position temperature drift of the sensor under the condition of not adding a special zero position bias adjusting module and a zero position temperature drift compensation module.

An embodiment of the invention discloses an integrated signal extraction method, an integrated signal extraction device, integrated signal extraction equipment, and a computer readable storage medium.The integrated signal extraction method comprises the steps of: S1, dividing a low-pass filtering time constant by a preset value to obtain a first order inertia time constant; S2, performing first order inertia operation on an input signal for the preset value number of times according to the first order inertia time constant, so as to obtain a preset value number of output signals; S3, averaging the preset value number of output signals to obtain a filtered signal, and outputting the filtered signal; S4, and performing additive operation on the input signal and the filtered signal, regarding a result of the operation as an input signal, and returning to the step S2. Compared with the prior art, the integrated signal extraction method provided by the invention effectively improves the efficiency of steady state deviation tracking of integral control, and is easy in engineering application.

The invention discloses a transconductance enhancement mode low voltage transconductance amplifier realized based on a complementary metal oxide semiconductor (CMOS) device, belonging to the field of design of analog integrated circuits. The amplifier comprises a differential input pair comprising a group of P-channel metal oxide semiconductor (PMOS) pipe and used for converting an input voltage signal into a current signal, a positive feedback diode comprising a group of N-channel metal oxide semiconductor (NMOS) pipe and used for enhancing transconductance through positive feedback, two groups of high-speed current mirrors used for copying an enhanced small signal current, and an output stage comprising NMOS and PMOS pipes and used for providing an output impedance and driving capability. The transconductance enhancement mode low voltage transconductance amplifier has the capability of working at low voltage, can increase the bandwidth by about at least two times compared with an original amplifier, and can save half power consumption, and low frequency gain also has a corresponding enhancement effect. The transconductance enhancement mode low voltage transconductance amplifier realized based on the CMOS device has a good practical prospect, and can be applied to multiple circuit modules, such as signal amplification circuits, AD/DA circuits and so on.

A compensating method for a ripple compensation circuit of a power supply is provided. The power supply includes an LLC resonant converter. The LLC resonant converter receives an input voltage and generates an output voltage. Firstly, the output voltage is subtracted from a reference voltage, so that a first error signal is generated. Then, a digital filter is provided to increase a low frequency gain of the first error signal, so that a second error signal is generated. Then, the first error signal and the second signal are added, so that a modulated error signal is generated. Then, a compensation signal is generated to control the LLC resonant converter according to the modulated error signal. Consequently, a low frequency gain of the input voltage is increased and a low frequency ripple of the output voltage is suppressed by an increased voltage loop compensator response.

The invention discloses a low-scattering broadband dual-polarized probe antenna based on a reverse four-ridge structure. The low-scattering broadband dual-polarized probe antenna comprises a circularopening waveguide, an axial ripple, the reverse four-ridge structure, a bottom supporting block and a feed coaxial line. A first end of the circular opening waveguide is closed, and the second end isprovided with an opening. The openings are arranged in the two ends of the axial ripple. The reverse four-ridge structure is a cross-shaped structure; an outer side of each ridge plate comprises a curve changing section and an impedance adjusting section; an outer ridge line of the curve change section is a three-order Bessel function; and the outer ridge line of the impedance adjusting section isa straight line. The bottom supporting block is a cross-shaped structure composed of four trapezoidal blocks, and the reverse four-ridge structure is connected with the circular opening waveguide through the bottom supporting block. And the feed coaxial line is electrically connected with the reverse four-ridge structure through a through hole in a side wall of the circular opening waveguide. Inthe invention, a bandwidth of the circular opening waveguide antenna is improved, and the antenna has advantages of a high cross polarization identification degree, a high port isolation degree, a smooth in-band gain change and a low scattering effect.

The invention belongs to the technical field of circuit control of piezoelectric ceramic actuators, and particularly relates to a driving method and driving circuit for a piezoelectric ceramic actuator. The method comprises the following steps: amplifying an input control signal to obtain a pre-amplification control signal V1; amplifying the sum of the V1 and a feedback signal V2 to obtain a voltage control signal V4, wherein the V2 is a signal obtained after voltage V0', which is output after a transformer T1 releases energy under the action of input voltage Vp, is divided by a resistor; calculating a PWM wave with a specific duty ratio by using a PWM control chip based on the V4 and feedback voltage V5, and allowing a primary coil to store energy or release energy under the action of the PWM wave and the inductance value of the transformer, wherein the voltage V0' is output during energy release, and the V5 is the voltage generated after current generated by the primary coil under the action of the Vp flows through a sampling resistor; and jointly controlling the unloading action of the voltage V0' by adopting the sum of V5 and V4 until the voltage V0 'reaches a target voltage. According to the method, in continuous adjustment of unloading action and boost control, the control precision of output voltage can be effectively improved, and output ripples can be reduced.

The invention provides a notch filter for a distributed power supply system, and belongs to the field of filters. The input end of the notch filter is connected with an inverter controller, the outputend of the notch filter is connected with an inverter filter, the input end of the inverter controller is connected with a grid-connected inverter, the output end of the inverter filter is connectedwith a grid-connected switch which is used for conducting and closing the distributed power supply system, the output end of the grid-connected switch is connected with a power grid meter, and the notch filter comprises a resonance circuit, the resonance circuit comprises a resistor R1, an inductor L1 connected with the resistor R1 in series, a capacitor C1 connected with the inductor L1 in series, the resistor R1 is connected with the inductor L1 in series, and the inductor L1 is connected with the capacitor C1 in series. The improved notch filter is adopted, the resonance peak of the inverter filter is suppressed, the stability of the distributed power supply system is kept, the distributed power supply system has small steady-state errors and enough stability margin, and the low-frequency-band gain is improved.

The invention discloses a current detection circuit and device applied to a load resistor. The current detection circuit comprises more than two groups of power supply processing circuits and a single-pole switch; each group of power supply processing circuit comprises a diode, a pull-up resistor and an MOS tube; the diode cathode of each group of power supply processing circuit is connected with one end of the single-pole switch, the anode is connected with the G pole of the MOS tube, the other end of the single-pole switch is grounded, one end of the pull-up resistor is connected with the positive end of an access power supply, the negative end of the access power supply is grounded, the S pole of the MOS tube is connected with the positive end of the access power supply, the D pole is connected with the positive end of an output power supply, and the negative end of the output power supply is grounded. The technical problems that a power supply control circuit of an electronic product with a multi-path input power supply uses a switch with a control end and a multi-path connecting end, so that the circuit is large in size, high in device cost and not beneficial to popularization and application are solved.

The application discloses a ripple wave compensating circuit for a power supply device and a compensating method therefor. The compensating method is suitable for the ripple wave compensating circuit for the power supply device. The power supply device comprises an LLC resonance oscillation converting circuit which is used for receiving input voltage and outputting output voltage. The compensating method comprises the following steps: (a) subtraction operation is performed on reference voltage and the output voltage, and therefore a first error signal is generated; (b) a digital filter is used for improving low frequency gain of the first error signal, and therefore a second error signal can be generated; (c) additive operation is performed on the first error signal and the second error signal, and therefore a modulation error signal is generated; (d) a compensation signal is generated correspondingly according to the modulation error signal so as to control the LLC resonance oscillation converting circuit, low frequency gain of LLC input voltage and response of a voltage loop compensation circuit can be increased, and the LLC resonance oscillation converting circuit is enabled to correspondingly output the output voltage for suppressing excessively low frequency ripple waves.