74results about How to "Wide operating frequency" patented technology

A calibration system is provided for calibrating frequency domain reflectometers in the field by using both the scattering parameters of the multi-port junction determined at the factory and changing the offset and gain terms used in generating a complex reflection coefficient by using internal calibrated loads so that heavy, cumbersome external calibrated transmission lines are not required. In one embodiment the internal calibrated loads include RLC circuits and in another embodiment the internal calibrated loads include attenuators. Further, retesting or recalibration does not necessitate reconnecting the cable under test, which may remain connected to the reflectometer's test port throughout the procedure.

A high-efficiency intelligent high-side electronic load switch with wide voltage adaptability comprises a power supply module, a core control module, a self-boosting module, a voltage detection module, a current detection module and a switching module. The core control module is used for signal acquisition, information processing and storage and logic control; firstly, the core control module receives an external switch control input signal and detection signals output by the current detection module and the voltage detection module and processes and analyzes monitoring data according to an internally stored program to control the switching module to complete corresponding actions; secondly, the core control module provides a PWM control signal for the self-boosting module. The voltage detection module and the current detection module are used for detecting the real-time operating voltage and current of the switching module and transmitting data to the core control module for processing and analysis. The self-boosting module is used for providing a driving voltage for a switching tube in the switching module. The switching module is used for executing the on-off actions of a load. The high-efficiency intelligent high-side electronic load switch is wide in operating voltage range, high in operating frequency, high in efficiency, low in loss, safe, reliable and programmable.

A method for improving the data acquisition efficiency of low voltage power line broadband carrier waves comprises the following steps: in a system constructed by a concentrator, acquirers and electric energy meters, the concentrator is in communication connection with the acquirers and the electric energy meters respectively and executes the steps of physical relation construction, concurrent acquisition and acquirer traversal; data acquisition is carried out by adopting a traditional data acquisition scheme when a physical topology relation table is not established; and after the physical topology relation table is established, the electric energy meters connected with different acquirers simultaneously execute a concurrent meter reading treatment technology and an asynchronous communication technology in order to make the concentrator simultaneously acquire data of the electric energy meters externally connected with N acquirers in a same zone area. The method for improving the data acquisition efficiency of low voltage power line broadband carrier waves has the concurrent meter reading treatment technology and the asynchronous communication technology and adopts a scheme for simultaneous parallel acquisition of the electric energy meter data by the different acquirers to substitute a traditional scheme for acquiring one by one according to the sequence of the electric energy meters, so the data acquisition efficiency is substantially improved.

The disclosed stripline resonator comprises two parallel metal ground plates 4, an inner conductor 5 between two plates 4, a metal short-circuit board 6 connected to with two ends of plate 4, and two coupling loops 7 on proper position of connected part of plate 4 and conductor 5 for input/output of microwave signal. The electromagnet parameter testing device for microwave film material comprises: a microwave signal source 1, a stripline resonator 2 with broad work frequency and small volume and testing error, and a SNA 3. This device can test the parameters in different microwave frequency range.

The invention discloses a high electromagnetic transmission composite structure for reducing the transmission loss of an electromagnetic wave. The high electromagnetic transmission composite structure includes a first composite structure layer, a second composite structure layer, and a first buffer layer. The first composite structure layer has a first thickness and a first dielectric constant. The second composite structure layer has a second thickness and a second dielectric constant. The first buffer is disposed between the first composite structure layer and the second composite structure layer and has a third thickness and a third dielectric constant. The transmission loss of the electromagnetism wave can be adjusted by adjusting the first thickness, the first dielectric constant, the second thickness, the second dielectric constant, the third thickness, and the third dielectric constant.

The invention provides a method for converting a digital signal to a synchro/rotary transformer signal. A circuit for realizing the method comprises a digital/sine-cosine signal converting circuit and an electronic SCOTT transformer. The digital/sine-cosine signal converting circuit receives 16-bit natural binary digital angle measurement and a reference signal with a frequency of DC-1 kHz, generates a high-precision 6.81-V sine-cosine signal, and sends the high-precision 6.81-V sine-cosine signal to the electronic SCOTT transformer; a line-line voltage 11.8-V synchro signal, a line-line voltage 11.8-V rotary transformer signal or a line-ground voltage 6.18-V sine-cosine signal is output by the electronic SCOTT transformer in different jumper manners; a conversion precision is +/-1 arc minute, and a signal frequency is DC-1 kHz; and a type of the output signal is a synchro/rotary transformer/sine-cosine signal programmable type. The method provided by the invention has the advantages of reasonable design, high precision, more output types, wide working frequency, strong adaptability and the like.

The invention relates to a bi-piezoelectric stack driving type precision rotary driving device, and belongs to the technical field of precision engineering. The bi-piezoelectric stack driving type precision rotary driving device comprises a support base, a rotary table, a stator assembly, a bearing and the like; the support base and the rotary table are connected through the bearing in a matched manner; the support base and the stator assembly are connected through a bolt; the rotary table and the stator assembly are contacted and matched through the front end of a driving foot; and the bearing, the support base and the rotary table are in interference fit. When an exciting electric signal acts on a stack type piezoelectric component, the stack type piezoelectric component performs axial elongation based on the inverse piezoelectric effect; therefore, the driving foot performs tangential displacement, so that the rotary table is driven to perform rotational motion; and the direction and the time sequence of driving voltage are changed, so that the rotary table can be controlled to perform forward rotation, inverse rotation and positioning stillness. The bi-piezoelectric stack driving type precision rotary driving device disclosed by the invention has the technical advantages of being simple in structure, high in positioning precision, large in stroke, rapid in response speed and the like, and has wide application prospect in the technical field of precision engineering.

The invention discloses an intelligent remote upgrade method of a collector in an electric meter collecting system. The method comprises the following steps of making a main station send a starting upgrade command to the collector; making the collector extract detection information from a command frame in the starting upgrade command; making the collector send a tentative frame to an electricity meter within a domination area, executing the next step if an effective frame is successfully collected, or exiting upgrade if the effective frame is not successfully collected; making the main station send an upgrade message to the collector; making the collector extract new software version information from the upgrade message, comparing the new software version with a current software version, executing the next step if the new software version number is higher than the current software version number, or exiting upgrade if the new software version number is not higher than the current software version number; making the collector send a response frame to the main station, exiting upgrade if a follow-up frame is not received within an effective time range, decompressing the received frame and afterwards storing the frame in external storage equipment if the frame is normally collected, and sending an upgraded frame after an upgrade message tail frame is received. According to the intelligent remote upgrade method of the collector in the electric meter collecting system, the collectors with addresses and without addresses can be subjected to intelligent remote upgrading.

A phase-locked loop (PLL) circuit including a voltage-controlled oscillator (VCO) with a variable gain is provided. A phase frequency detector (PFD) detects a phase difference between a reference signal and a PLL feedback signal. A charge pump and a loop filter sequentially process an output signal of the PFD. A VCO has different gains according to a mode transition. A control voltage applied to the VCO is selected from an output signal of the loop filter and an additional control signal according to the mode transition.

The invention discloses broadband radio frequency sampling mixer, and belongs to the technical field of radio frequency. The mixer comprises a pulse generator, a microstrip line-trough line conversion Balun and a sampling gate diode circuit. The pulse generator in the mixer provided by the invention makes an input 50MHz local oscillator signal generate abundant harmonic components needed by sampling, harmonic frequency covers 2MHz-6GHz, the generated pulse signal is high in signal amplitude and good in phase noise, meanwhile the pulse signal can be prevented from returning back to the input end of an local oscillator, and isolation degrees of the local oscillator, radio frequency and intermediate frequency are improved; the microstrip line/trough line Balun adopts a microstrip line and trough line conversion structure, as the 1/4 wave length trough line forming circuit is used, the microstrip line/trough line Balun has an extremely small insertion loss and standing-wave coefficient, reflection of the microwave pulse signal is reduced, and transmission of the microwave pulse signal is more facilitated; an intermediate frequency signal generated by sampling and mixing is high in signal amplitude and good in signal purity; the whole circuit can be integrated onto a printed circuit board, so that the volume is small and the cost is low.

The invention relates to a bionic multi-degree of freedom precise piezoelectric driving device and belongs to the precise machining field. The multi-degree of freedom precise piezoelectric driving device is formed by a rotor and a stator; the stator comprises a first layer, a second layer and a third layer which form into an integral structure through flexible hinges; a thin wall flexible hinge, a rotation driving mechanism and a straight line driving mechanism are packed inside the stator. According to the multi-degree of freedom precise piezoelectric driving device, stepping forward and reverse 360-degree continuous rotational motion and straight line motion of the rotor are achieved based on a loopworm movement principle through the forward reasoning function of piezoelectric stack, the reverse elastic function of the flexible hinges and the clamping function of the flexible hinges. The multi-degree of freedom precise piezoelectric driving device has the advantages of being compact in structure, compact, high in displacement control accuracy, rapid in response, low in driving power, wide in working frequency and high in benefit, applied to fields such as ultraprecise machine tools, micro electro mechanical systems, precision optics, aerospace and robots and wide in development prospect and application values.

The invention discloses an air repeater for an LTE base station. The air repeater comprises a forwarding unit, a radio frequency front end and a transmitting/receiving antenna. Signals are forwarded after distortion-free spectrum shifting and amplification in air, and then the received spectra are restored on the ground to realize forwarding of the LTE signals. Moreover, the system has the advantages of low cost, simple erection, strong maintainability, low power consumption, high reliability and the like, and the air forwarding unit is flexible in erection position, thereby solving the problem that the erection cost of the base station in blind area coverage as well as some remote regions and regions with few users is too high; a variable gain amplifier with a large dynamic range is integrated inside to achieve long-distance and near-distance coverage; the transmitting and receiving time slots are automatically switched, the switching time can be ignored, and data loss caused by the switching delay will not occur; and the variable range of the frequency of each part in the system is wide, the frequency band is convenient to change for forwarding, only the filter frequency band needs to be correspondingly changed, and the expandability and the universality are strong.

The invention discloses a self-calibrating device and method for reducing local oscillation leakage of a broadband frequency mixer. The device comprises an RF switch (1), the broadband frequency mixer (2), a broadband combiner (3), a broadband coupler (4), a broadband detector (5), a controller (6), a broadband phase shifter (7), an analog attenuator (8) and a broadband local-oscillation coupler (9). According to the invention, a feedforward technology is used, from the aspect of local oscillation, local oscillation signals same in the amplitude and opposite in phases are introduced intentionally in the output end of the frequency mixer, and local oscillation leakage is reduced; the device and method are suitable for any frequency conversion systems including frequency conversion related reception and emission systems, and application is wide; and the device and method also have the advantages including wide working frequency, high local oscillation inhibition performance, automatic calibration, small debugging amount of high productibility. On the original basis, local oscillation inhibition can be improved by more than 30dB, and the isolation performance of the broadband frequency mixer is improved.

The invention discloses a broadband end-fire antenna array for a millimeter wave communication system. A power division network is designed by using a substrate-integrated coaxial line (SICL), an electromagnetic dipole antenna with a broadband working range is selected as a radiating element, and a broadband and high-gain antenna array is achieved by adopting a planar L-shaped probe excitation antenna. The broadband power division network employing the SICL disclosed by the invention has a wider working bandwidth in a millimeter wave band in comparison with the power division network employinga substrate-integrated waveguide transmission structure design, and has lower losses in the millimeter wave band in comparison with the power division network employing a microstrip line and a coplanar waveguide transmission structure design. The end-fire antenna array disclosed by the invention has the advantages of wide impedance bandwidth and radiation pattern bandwidth.

The invention discloses a broadband multilayer microstrip Butler beamforming network matrix device, and belongs to the technical field of electronic communication in order to solve the defects, such as a narrow operating frequency, a large port phase shift error, and poor port amplitude flatness, of a current Butler matrix. The broadband multilayer microstrip Butler beamforming network matrix device is easy to manufacture, low in cost, high in port phase shift accuracy, small in port amplitude fluctuation, low in loss, wide in operating frequency and high in port isolation degree, can meet therequirements of modern civilian mobile communication systems and military radar systems for new-generation multi-beam array antennas and antenna testing.

The invention relates to a vibration type energy collector, which comprises a bias voltage generating device, at least two moving pole plates and an isolation device, wherein the moving pole plates are arranged in a laminated way; the isolation device is arranged between the two moving pole plates and is used for enabling the two adjacent moving pole plates to maintain the preset space under the external-force-free effect; each moving pole plate respectively comprises a support component, a moving mass block and an electrode layer; the support component is arranged on the periphery of the moving mass block and supports the moving mass block; the electrode layer is arranged on the surface, opposite to the adjacent moving pole plate, on each moving pole plate; the bias voltage generating device is positioned between the two moving pole plates and is arranged on the surface of one electrode layer; the bias voltage generating device is used for forming a fixed electric field between the two adjacent moving pole plates. The vibration type energy collector has the advantages that the work frequency is wide, so that the device has high energy collection efficiency in the frequency range. The invention also provides a preparation method of the vibration energy collector.

The invention provides a pneumatic precision positioning mechanism with a piezoelectric microdisplacement compensation function. The neumatic precision positioning mechanism consists of a cylinder, a piezo-ceramic displacement amplification mechanism, a second slider, a first slider, a guide rail 7, a glass ruler 9 of a grating sensor, a first reading head of a grating sensor, a second reading head of the grating sensor, a worktable, a first connecting piece, a second connecting piece, a sixth connecting piece, a fifth connecting piece, a seventh connecting piece and a third connecting piece, wherein the cylinder and the worktable are connected through the first connecting piece and the second connecting piece; the cylinder is connected with the piezo-ceramic displacement amplification mechanism and the first slider through the fourth connecting piece; the fourth connecting piece is connected with the first reading head of the grating sensor through the sixth connecting piece; a displacement output shaft of the piezo-ceramic displacement amplification mechanism is connected with the second slider through the fifth connecting piece; the fifth connecting piece is connected with the second reading head of the grating sensor through the seventh connecting piece; and the guide rail is connected with the worktable through the third connecting piece. According to the pneumatic precision positioning mechanism, microdisplacement output by piezo-ceramic is utilized to make up for output displacement accuracy of the cylinder, so that large-stroke high-precision positioning is realized.