128results about How to "Improved Gain Flatness" patented technology

The invention discloses a drive power amplifier with the adjustable gain of a 0.1-3GHz CMOS. The drive power amplifier comprises an input match circuit, an ultra-wideband drive stage amplifying circuit, a gain-adjustable amplifying circuit, an ultra-wideband power amplifying circuit and an output blocking circuit. A first ultra-wideband drive stage is used for achieving preceding-stage gain and ensuring ultra-wideband input match of the whole circuit. A gain control circuit is used for controlling power gain of wideband radio frequency signals and the good inter-ultra-wideband matching property. A third ultra-wideband drive power stage is used for ensuring large power output of the whole circuit and the good wideband output matching property. A three-stage stacking structure is combined with a compensation capacitance circuit, and the area of a chip is small. In the whole circuit, parameters of an adopted component can be determined according to indexes of items such as the whole circuit gain, the wideband and the output power, and therefore the adjustable gain, the high-linearity and the high drive power within the 0.1-3GHz can be achieved.

A series-fed E-shaped patch antenna array has co-polarized parasitic patches to improve aperture efficiency. Each of microstrip parasitic patches is inserted between a plurality of microstrip E-shaped patch antennas. The parasitic patches are co-polarized with the E-shaped patch antennas so that the current flows in the parasitic patches and the E-shaped patch antennas have the same polarity. Additional radiation from the co-polarized microstrip parasitic patches significantly improves gain flatness, gain and aperture efficiency due to offset resonance frequency.

The invention discloses an ultra-wideband miniaturized radio frequency module. An input signal passing a low pass filter A (1) and a limiter (2) and a calibration signal passing a single knife doublethrow switch A (3) are selected by a single knife double throw switch B (4), and then selected through a single knife four throw switch A (5); then power control is performed through a low noise amplifier A (6), a low noise amplifier B (7), a direct connector (8) and one of the four ways of a fixed attenuator; then power adjustment is performed through a single knife four throw switch B (10), a numerical attenuator (11) and an amplifier A (12); then selection is carried out by a single knife six throw switch A (13), and frequency selection is carried out through one of the six ways of a band-pass filter; and a local oscillator signal passes a mixer (26) and a low pass filter B (27) to obtain an intermediate frequency signal. The ultra-wideband miniaturized radio frequency module solves theproblems of the ultra-wideband low noise design, the gain flatness control, the anti-interference and the miniaturization.

The invention discloses an ultra-wideband planar monopole antenna. The ultra-wideband planar monopole antenna comprises a dielectric substrate, a monopole radiation patch, a lumped device and a grounding plate, wherein the monopole radiation patch is formed by loading a monopole antenna main body and a top end, a part, near to the grounding plate, of the monopole radiation patch employs a triangular corner and is mainly used for impedance matching of a high-frequency part. A lumped component loaded by the antenna main body is mainly used for reducing a working frequency band of the antenna andgain of a smooth antenna in the whole frequency band, a plurality of rectangular open-circuit branches are loaded at a top end of a monopole, the capacitance between the antenna and floor is improved, and the working frequency band of the antenna is further reduced. By loading the lumped component and additionally arranging open-circuit branches on ground, the antenna size is effectively reducedas well as favorable ultra-wideband characteristic is maintained, and the application of the antenna in the monitoring field is facilitated.

The invention relates to the technical field of short-wave wireless communication and provides a short-wave high-linearity balance structure power amplifier. The short-wave high-linearity balance structure power amplifier comprises an input Balun, two same amplification circuit modules, an adjustable DC bias circuit module and an output Balun, wherein radio frequency input signals are coupled to two balance signals having a phase difference of 180 degrees through the input Balun, the two balance signals are respectively input to the two amplification circuit modules, output signals of the two amplification circuit modules are coupled to single-signal output through the output Balun, and the adjustable DC bias circuit module is used for providing DC bias for the two amplification circuit modules; each amplification circuit modules comprises an amplification circuit and a negative feedback circuit, each amplification circuit is composed of two transistors through cascading by use of a common-emitter and common-base mode, each negative feedback circuit is composed of a directional coupler, and the negative feedback circuits are connected with the input ends and the output ends of the amplification circuits. The power amplifier employs a balance structure, is simple in structure and also has the advantages of high linearity and high output power.

The invention discloses a KU wave-band low noise amplifier. The KU wave-band low noise amplifier comprises a first-stage cascade-inductance-source-stage negative feedback structure, an inter-stage matching network and a second-stage cascade-inductance-source-stage negative feedback structure; the first-stage cascade-inductance-source-stage negative feedback structure is connected with the second-stage cascade-inductance-source-stage negative feedback structure through the inter-stage matching network. The KU wave-band low noise amplifier has the advantages that (1) the work frequency band ranges from 12 GHz to 18 GHz; (2) the minimum value of the gain (S21) is 20 dB, and the good gain flatness is achieved; (3) the noise factor of an input matching S11 and the noise factor of an output matching S22 are smaller than -10 dB in the work bandwidth; (4) K is larger than 1 in a wave band; in other words, the circuit meets the requirements of the unconditional stability.

These glasses incorporate a combination of F and Al2O3 to achieve even wider fluorescence and improved gain flatness. In addition, SPCVD incorporates large amounts of N into low-loss fiber whose high charge has an impact on rare earth behavior. The Surface Plasma Chemical Vapor Deposition (SPCVD) produces fiber preforms with high levels of F, Al2O3, and N. These heavily fluorinated glasses provide much broader Er3+ emission than Type I or Type II silica for enhanced multichannel amplifiers. SPCVD successfully fluorinates silica with losses below 5 dB/km and increased Er3+ emission width.

The invention discloses a low-noise frequency mixer circuit. The low-noise frequency mixer circuit comprises a noise elimination trans-conductance input stage, a switch mixing stage and an output load stage, wherein the noise elimination trans-conductance input stage receives a RF voltage signal and converts the RF voltage signal into a current signal; the switch mixing stage is controlled through a local oscillator LO to periodically reverse the current signal and convert the frequency into an intermediate frequency from a radio frequency to finish the frequency conversion; the output load stage carries out filter suppression on a high-frequency signal and converts the corresponding intermediate-frequency signal into an output IF voltage signal. The low-noise frequency mixer circuit improves the effective input trans-conductance of the trans-conductance stage through using a cross coupling method at the noise elimination trans-conductance input stage so as to lower the power consumption of the circuit and achieve low noise.

The invention discloses a single-end input and double-end output gain adjustable low noise amplifier. The amplifier comprises a single-end input end, a single-to-differential amplification circuit (100), a first level buffer circuit (200), a second level buffer circuit (300), a first differential output end and a second differential output end. The single-end input end is used for inputting single-end input signals; the single-to-differential amplification circuit (100) is used for carrying out differential amplification to the single-end input signals; the first level buffer circuit (200) is used for filtering and amplifying the differential signals output by the single-to-differential amplification circuit (100); the second level buffer circuit (300) is used for further amplifying and carrying out phase and amplitude adjustment to the differential signals output by the first level buffer circuit (200); and the first differential output end and the second differential output end are used for selectively outputting the differential output signals of the low noise amplifier. According to the amplifier, the circuit gain is adjustable; and output signal balance and gain flatness are realized.

The invention provides a one-dimensional wide-angle scanning phased array based on a rectangular patch TM20 mode, and relates to the technical field of microwave antennas. The structure of the phasedarray provided by the invention is mainly composed of an array antenna patch, a feeding part and a dielectric substrate, and the array is composed of 8 identical units arranged at equal intervals. Since the performance of the phased array has a great relationship with the array units, the invention makes an improvement based on the rectangular patch TM20 mode, expands the unit beam, and further broadens the phased array scanning range. Under the premise of ensuring the same polarization in the scanning process, through miniaturization technology, the unit size is reduced, the unit spacing is increased to a certain extent, the mutual coupling effect among the units is reduced, and a good impedance matching effect in the beam scanning process is ensured.

The invention discloses a multi-channel feedback type broadband low-noise amplifier which comprises an input module electrically connected with an input end RFin of the low-noise amplifier and used for receiving and processing an input signal of the low-noise amplifier; an amplification module electrically connected with the input module and is used for receiving and amplifying the signal output by the input module to obtain an amplified signal; and an output module electrically connected with the amplification module and the output end RFout of the low-noise amplifier, and is used for processing the amplified signal and outputting the processed amplified signal. According to the low-noise amplifier designed by the invention, the cascaded amplifying circuit is adopted. The problem that a low-noise amplifier achieves low noise in a wide frequency band and the problem that a broadband low-noise amplifier has gain roll-off in a high frequency are solved in different amplifying circuits, good noise and gain response in a broadband are achieved, meanwhile, the design pressure of each stage of circuit is relieved, and the performance performance of the whole amplifier is improved.

The invention discloses a broadband harmonic suppression amplifier, which belongs to the technical field of integrated circuits and comprises an input matching network, a broadband current multiplexing amplification network, a first active bias network, a harmonic suppression balance matching network, a broadband common-source amplification network, a second active bias network and an output matching network. The broadband current multiplexing and common-source amplification network is adopted, the grid-source RLC parallel negative feedback circuit is matched, the characteristics of broadband, high gain and low power consumption are achieved, the harmonic suppression balance matching network is adopted between stages, the harmonic suppression degree of the amplifier is improved, meanwhile, impedance matching and gain flatness can be considered, and the power consumption is reduced. The antenna has the advantages of wide working frequency band, low noise coefficient, high gain, high harmonic suppression degree, low power consumption and the like.

The invention relates to the technical field of microwave antennas, in particular to a broadband end-fire antenna on the basis of surface wave waveguide and high-impedance surfaces. The broadband end-fire antenna comprises a first dielectric substrate, a second dielectric substrate, a surface wave waveguide portion, a high-impedance surface portion and a surface wave exciter portion. The broadbandend-fire antenna which is a panel end-fire antenna has the advantages that end-fire effects can be realized by surface wave conduction and suppression functions of the surface wave waveguide and thehigh-impedance surfaces, and the broadband end-fire antenna is excellent in characteristics such as radiation gain, front-to-back ratio and gain flatness; two resonant modes in the surface wave waveguide can be excited, the high-impedance surfaces with the broad stop band characteristics are adopted, accordingly, the broadband end-fire antenna has a broadband function, and the relative central bandwidths can reach 33.5%; the panel antenna has the end-fire radiation performance and broad impedance bandwidth functions, and is simple in structure and easy to implement and integrate, and the performance of the antenna can be effectively enhanced when the broadband end-fire antenna is applied to radar, communication, remote sensing and measuring, electronic countermeasures and the like.

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 discloses a broadband big power test clamp. The broadband big power test clamp comprises a circuit sheet fixed on a structure member; a microwave coaxial connector is welded on the circuit sheet through an insulator to form a microwave signal path; an impedance conversion line, a DC offset line and a grounding line are manufactured on a circuit sheet; the DC power supply pedestal is welded on the circuit sheet through a lead; chip-type microwave broadband capacitors are arranged on an input end and an output end of the clamp; a filtering capacitor is connected between the DC offset line and the grounding line of the circuit sheet through a scolding tin welding mode; and a chip-type resistor and an electrolytic capacitor are arranged on the circuit sheet through the soldering tin welding mode. Compared with the prior art, the beneficial effects of the broadband big power test clamp are that: through analogue simulation of ADS software, an in-band gain sink of the broadband big power test clamp can be effectively eliminated and the gain flatness can be improved. The broadband big power test clamp can effectively inhibit the in-band sink of the broadband big power test clamp and improves the in-band gain flatness.

The invention discloses a conformal spherical antenna array with a good shielding effect. The antenna array comprises a radome (13), an antenna array (14), a shield cover (15) and a base plate (16). The antenna array (14) is arranged on the base plate (16). The shield cover (15) is located between the antenna array (14) and the base plate (16). The antenna array (14) is covered by the radome (13). The base plate (16) is provided with an annular groove (18). The lower edge of the radome (13) is inserted into the annular groove (18) and is positioned by a locking positioning mechanism. The antenna array (14) comprises a first skeleton (1), a second skeleton (2), a third skeleton (3), an antenna (11) and a positioning device (10). The conformal spherical antenna array provided by the invention has the advantages of high antenna radiation uniformity, high structural strength and good shielding effect.

The invention relates to a PCB (Printed Circuit Board) dual-frequency communication antenna. The PCB dual-frequency communication antenna comprises a PCB, a radiating body, a feed-in part and a grounding part, wherein the radiating body and the feed-in part are embedded into the front side of the PCB; the radiating body is connected with the feed-in part, and is used for receiving and transmitting an electromagnetic wave signal; the grounding part is embedded into the back side of the PCB, and is positioned on the same side as the feed-in part. In the PCB dual-frequency communication antenna, a PCB dual-ring series-connection structure is adopted, so that 2.4G and 5.8G are designed integrally, and the antenna is minimized; the working bandwidth of the antenna is extended by an arc-shaped recess between a radiating body projection and a floor, and high gain flatness is achieved; a printed molding antenna technology is adopted, so that the antenna is easy to machine.

The invention discloses an S wave band GaN MMIC low noise amplifier. The circuit structure includes a first-stage field effect transistor amplifier, an input matching network, a first-stage gate biasnetwork, a first-stage drain resistor, a first-stage drain bias network, an inter-stage matching network, a second-stage gate resistor, a second-stage field effect transistor amplifier, an output-stage matching network, a second-stage drain bias network, a second-stage drain resistor and a second-stage gate bias network are included. The negative feedback network formed by the resistor enhances the stability of the circuit, adjusts the gain of the circuit, and improves the linearity of the low-noise amplifier. Performance of large radio frequency input signals, low noise coefficient and good gain flatness in a working band of the low-noise amplifier can be realized.