136results about How to "Improve Phase Consistency" patented technology

The invention discloses a frequency changing method of digital middle-frequency signals used in a repeater station system, which comprises two steps of an up frequency changing process and a down frequency changing process: in the down frequency changing process, the middle-frequency signals after digital analog conversion are processed by digital wave filtering processes such as an extraction process, a bandpass compensation, a signal shaping process, etc. after a digital frequency mixing process, the middle-frequency signals can be moved to a zero middle-frequency, a digital signal with the high speed rate can extracted as two-channel quadrature digital baseband I, Q signal with a low speed rate; in the up frequency changing process, the digital baseband I, Q signals acquired from the down frequency changing process are processed by an interpolation filtering process, then processed by I, Q modulation process and a secondary frequency mixing process, and the signals can be processed by a gain adjustment and control, finally high speed digital middle-frequency signals are outputted. Correspondingly, the invention also discloses a frequency changing system thereof. The invention can be achieved by using PLC units such as FPGA, CPLD, EPLD and DSP, etc., which can improve the integration degree of repeater station equipment; meanwhile, an ASIC chip is removed to decrease heating capacity and to improve the reliability.

The invention provides a compact antenna feed calibration network, and aims at providing the highly-versatile and reliable integrated feed calibration network used for antennas of a base station. According to the compact antenna feed calibration network, an upper-layer antenna metal floor (1) as a top layer is provided with a corresponding intermediate-layer antenna combiner feed network (2) and embedded grooves, combiner modules are embedded into the embedded grooves, the embedded grooves are arranged in a staggered manner at the same interval, combiners are connected antenna ports and ports corresponding to a lower-layer antenna calibration network (3) via four different model design modules, two combiners needed by dual polarization of every two unit subarrays serve as one module, and the modules are fastened and combined with the upper-layer antenna metal floor in a modularized installation way. the intermediate-layer antenna combiner feed network for connecting an antenna unit with the lower-layer antenna calibration network is formed, the lower-layer antenna calibration network is of a strip line structure, and 32 parallel coupling linear directional couplers (15) and a 1-to-32 power divider (14) are distributed in an H-shaped PCB of the lower-layer antenna calibration network.

The invention belonging to the field of the millimeter wave technology discloses a millimeter-wave broadband ridged probe radial waveguide power divider / combiner. The radial waveguide power divider / combiner comprises a coaxial input waveguide, a transition structure, a radial waveguide, and an N-path ridged probe coupled output array. According to the invention, with the broadband low-reflection transition structure for the coaxial waveguide to the radial waveguide, a matched circular ring structure, and the power distribution mode of the ridge probe, the working bandwidth of the power divider / combiner is increased; the radial waveguide power divider completes power distribution by one-time operation, so that the path losses of the power distribution is reduced; and because of the circumferential symmetry of the structure and the radial waveguide working mode, the amplitude-phase consistency of all paths of signals after distribution is guaranteed, so that the high power synthesis efficiency of the power combiner is realized.

The invention relates to an arbitrary polarized wave generation and calibration method. The generation method comprises the following steps: generating digital signals in a base band, and carrying out amplitude-phase adjustment and compensation on two paths of orthogonal digital signals; and converting the digital signals into analog signals, up-converting the analog signals into radio frequency signals, carrying out power amplification and distribution on the radio frequency signals through two transmitters, and synthesizing polarized waves in arbitrary polarization directions in an ortho-mode coupler by two signals. In the design of polarized signal calibration, the calibration method includes steps of coupling two paths of a few signals from two paths of transmission signals to enter calibration channels; comparing the consistency of signals in the two channels and searching the minimum difference of two phases of polarization signals by using an optimization algorithm; and comparing the differences of the two paths of signals, feeding the differences back to a polarized wave generation unit, and measuring and compensating the generated signals so as to ensure the consistency of the signals in the two channels.

The invention discloses a high-gain and high-isolation millimeter wave double-balance passive subharmonic mixer. The passive subharmonic mixer comprises an active balun radio-frequency input stage, apassive balun local oscillator input stage, a passive subharmonic mixing stage and a transimpedance output stage. Radio-frequency signals amplified by an active balun and local oscillator differentialsignals generated by a passive balun are subjected to subharmonic mixing, and intermediate-frequency signals are output through a transimpedance amplifier. In the mixing stage, local oscillator signals are injected from the source of a transistor, and radio-frequency signals are injected from the grid of the transistor, so that the conversion gain is increased. In the active balun, a cross coupling tube is added on the basis of a cascade differential pair structure to improve the amplitude and phase consistency. In the transimpedance amplifier, a cross coupling structure is utilized to increase the gain, decrease the input and output impedance, improve the input current amplification capability and the output drive capability and further increase the conversion gain. The passive subharmonic mixer has the advantages of being high in conversion gain, high in port isolation and the like, and is suitable for the application scenarios of mixing with single-ended input and differential output.

The invention relates to the field of radar communication, in particular, a low profile miniaturized phased array antenna is realized in a three-dimensional integrated manner, comprises an antenna TRmodule and a power supply and differentiator module, the high frequency signal interconnection between the antenna tr module and the power supply and differentiator module is implemented using radio frequency vertical interconnection, A low frequency interconnect is implement using a low frequency pin, the antenna TR module comprises an antenna TR module cavity, Antenna TR module printed circuit board and wave control PCB board, A printed circuit board of the antenna TR module and a waveform control PCB are respectively arranged on both sides of the cavity of the antenna TR module, As that microwave multilayer PCB board is use, the vertical interconnection between layers is realize, thereby realizing ultra-small longitudinal dimension integration, vertical interconnection blind insertion mode is adopted between the soft substrate part of the summer module and the prin circuit board of the antenna TR module, and the radio frequency traces are reduced by using the vertical interconnection between layers inside the microwave multilayer board.

The invention provides an active millimeter wave imaging security detection system and a security detection method. The security detection system comprises a millimeter wave signal receiving-transmitting integrated machine for generating and sending a millimeter wave signal needed by a detected object and receiving and processing an echo signal returned by the detected object, and a one-dimensional scanning platform for installing and driving the millimeter wave signal receiving-transmitting integrated machine to be moved along a Z-axis direction. The active millimeter wave imaging security detection system uses a synthetic aperture radar imaging principle, the front and back faces of the detected object are rapidly imaged, the imaging resolution ratio is high, and the great convenience isprovided to the detected object and a security person. The detected object only needs to stand in a security detector for 2 seconds, and the security person only needs to detect a suspicious object according to a suspicious object identification result displayed by an image display module, so a problem that the security person uses a security detection device to be backwards and forwards moved ona body of the detected object so as to produce the inconvenience can be solved.

The invention discloses an autonomous extracting method for a non-stable low-frequency line spectrum of ship noise. The method comprises the following steps of (1), performing ship noise long-integration power spectrum line spectrum first detection, and obtaining a suspected line spectrum; (2), for aiming at the suspected line spectrum, setting the number of segments in segmented power spectrum analysis and the interval length of the integration domain; (3), for aiming at the suspected line spectrum, setting the integration domain starting point in analysis of each segmented power spectrum; (4), performing ship noise secondary power spectrum estimation according to the preset integration domain starting point and the interval length; and (5), performing continuous spectrum automatic offsetand line spectrum autonomous identification extraction. The method aims at a difficulty of autonomous extraction for the non-stable low-frequency line spectrum of the ship noise; through automatic analysis for a non-stable characteristic of the low-frequency line spectrum of the ship noise, adaptive adjustment is performed on the number of segments in segmented power spectrum analysis, the integration domain starting point and the interval length, thereby improving tolerance of the power spectrum to the line spectrum non-stable characteristic, improving signal-to-noise ratio of the line spectrum, and realizing autonomous extraction to the non-stable low-frequency line spectrum of the ship noise through automatic continuous spectrum offset and autonomous line spectrum identification.

The invention discloses a method and a system for generating Ka band multi-path millimeter wave signals, and belongs to the technical field of electronics. The method comprises the following steps of: doubling frequencies of low-frequency local oscillation signals to a Ku band by adopting a single frequency doubling chain, dividing the power of the local oscillation signals into N paths in the Kuband, then doubling the frequencies of the selected M paths with good amplitude and phase consistency to a Ka band, and performing frequency conversion to the Ka band meeting the application requirement through a frequency mixer after filtering. The method can generate multiple paths of Ka band millimeter wave signals with good amplitude and phase consistency to meet the application requirement of a Ka band millimeter wave complete system, meanwhile, is easy to implement, and has the characteristics of relatively simple circuits and relatively low cost.

The invention relates to a terahertz substrate integrated waveguide multi-channel power divider adopting an air lens, suitable for terahertz (THz) frequency band. Input and output adopt substrate integrated waveguide H-surface horn antennas for feeding and receiving energy; a medium substrate layer is slotted to form the air lens and finite periodic air phase gratings, which can be effectively used for conversion and distribution of wave beam; by reasonably designing the air lens and the finite periodic air phase gratings, the single-layer double-channel power division output can be performed, and by using N (N is a natural number) layers of medium substrates, the 2*N-channel array power division / synthesis can be performed; the signal transmission loss is reduced to the maximum extent. The multi-channel power divider has excellent characteristics of high efficiency, miniaturization, stable performance, good input standing-wave ratio and the like, has the advantages of good consistency of signal amplitudes / phases of power division output ports and the like, is mainly used for THz power synthesis amplification systems, phased-array antenna feed networks and the like, and has a wide application prospect in THz systems of communication, radar, measurement and control and the like.

The invention discloses a space frequency two-dimensional spectrum estimation method based on a compressed sampling array, which mainly solves a problem that data storage is enabled to become extremely difficult because a surprising amount of data in conditions of a high sampling rate and multiple channels. Implementation of the method comprises the steps of 1) using signals acquired by receives of N1 antennas to act as an input signal matrix X; 2) generating an observation matrix Y according to the input signal matrix X; 3) constructing frequency domain basis matrix F, and setting a time domain compression matrix Phib and joint sparse matrix Zf according to the observation matrix Y, and establishing a signal model Y<T>=PhibFZf; 4) solving the signal model so as to acquire the joint sparse matrix Zf, and acquiring a non-zero support set Gamma according the joint sparse matrix; and 5) solving a space frequency two-dimensional spectrum Zp according to the non-zero support set Gamma. The method disclosed by the invention reduce the number of channels and the time domain sampling rate of the system, improves the transient signal receiving bandwidth and the direction finding precision, and can be applied to a radar and reconnaissance integration system.

The invention provides an S-band continuous-wave solid-state high power amplification device. The S-band continuous-wave solid-state high power amplification device consists of an S-band solid-state high power amplifier A, an S-band solid-state high power amplifier B, a switching unit and a power transmitting unit, wherein the switching unit comprises a coaxial electric switch, a waveguide electric switch and an electric switch controller; the input ends of the S-band solid-state high power amplifier A and the S-band solid-state high power amplifier B are connected with the coaxial electric switch respectively; the output ends of the S-band solid-state high power amplifier A and the S-band solid-state high power amplifier B are connected with one end of the waveguide electric switch respectively; the other end of the waveguide electric switch is connected with the power transmitting unit; the input end of the electric switch controller is connected with the output end of the power transmitting unit; and the output end of the electric switch controller is connected with the S-band solid-state high power amplifier A and the S-band solid-state high power amplifier B respectively. The S-band continuous-wave solid-state high power amplification device has the advantages of large instantaneous bandwidth, no tuning requirements, high efficiency, high reliability, easiness in operation, long service lifetime, low failure rate and the like.

The present invention relates to a method for implementing clock redundancy backup in base station of WCDMA system and its equipment. Said equipment includes two clock plates and service plates. The system reference source input signal can be simultaneously transferred into the described two clock plates, said described two clock plates can respectively utilize a clock bus to transfer the produced 30.72MHz working clock signal into service plate. The working clock signal outputted by main / backup clock plates adopting said method can be produced by using clock signal of same clock plate as reference double frequency, when switching, the phases of all the service plates can be smoothly transited and can continuously retain synchronization, and the phase change rate can be accurately controlled, so that it can implement clock redundancy backup and quick and smooth switching.

Embodiments of the invention are a novel splicing detection scheme that detects the spliced images by distinguishing image features that are extracted by exploiting both magnitude and phase information of a given image. The image features include the statistical moments of characteristic functions of wavelet subbands of a test image and a prediction-error image. In addition, the approximation (LL) subband at different levels is individually erased by forcing the wavelet coefficients to zero and the inverse wavelet transform is applied in order to produce reconstructed image with enhanced high frequency components. Further, the moments of the characteristic functions of these reconstructed images provide additional image features. Moreover, the statistics (mean, variance, skewness and kurtosis) of 2-D phase congruency array associated with the reconstructed images provide additional image features for splicing detection. These inputs provide a 120 dimensional image feature vector that includes 96 moment features and 24 phase features.

The invention provides a phase-locked loop circuit, a system with multiple phase-locked loops and an output phase synchronization method thereof. The invention includes a frequency divider for frequency division of an output signal, a sampler which samples the frequency-divided signal based on the output signal to obtain a feedback signal to ensure that the phase of the feedback signal is consistent with the phase of the output signal, a phase frequency detector which determines the phase difference between the feedback signal output by the sampler and the input crystal oscillator signal to generate a pulse signal, a charge pump which generates tuning voltages based on the pulse signal, and a voltage controlled oscillator which adjusts the frequency of the output signal based on the tuningvoltages. In the invention, a sampling method is adopted to realize the phase consistency of the feedback signal and the output signal of the phase-locked loop circuits. Thus the phase consistency between the output signal and the input crystal oscillator signal is greatly improved. Besides, in the system with multiple phase-locked loops, the phase of the output signals of all phase-locked loop circuits is ensured to be consistent so as to improve the system performance.

The invention relates to a quasi-planar high-isolation multi-path power divider. An input radio-frequency signal is subjected to multi-path power allocating and input impedance matching through an upper-level power dividing network. Meanwhile, the insulating characteristics and the output VSWR at all output ports are ensured to be excellent through a lower-level isolating network and an isolation resistor. The upper-level power dividing network and the lower-level isolating network are connected via metallized through holes. According to the technical scheme of the invention, the advantages of a quasi-planar structure, including multiple ports, high isolation, low insertion loss, good input / output standing wave ratio, wide band, small volume, good consistency of signal amplitudes / phases at all output ports, and the like, are realized. Meanwhile, the quasi-planar high-isolation multi-path power divider is convenient to design and the infinite multi-path power distribution can be realized theoretically. The quasi-planar high-isolation multi-path power divider is mainly applied to microwave and millimeter wave power synthesis and amplification systems, phased array antenna feed networks and the like. The quasi-planar high-isolation multi-path power divider has a wide application prospect in the fields of microwave and millimeter wave systems for communication, radar, measurement, control and the like.

The invention discloses a compact Wilkinson power divider, which comprises an input port, a first output port and a second output port, wherein the input port is connected with the first output port through an input line, a first transmission line and a first output line which are sequentially connected in series; the input port is connected with the second output port through the input line, a second transmission line and a second output line which are sequentially connected in series; the intersected common end of the first transmission line and the second transmission line is connected witha grounded first capacitor in parallel, the other end of the first transmission line is connected with a grounded second capacitor in parallel and the other end of the second transmission line is connected with a grounded third capacitor in parallel; and a direct isolation resistor is connected between the first transmission line and the second transmission line. The problem of relatively large area of a traditional Wilkinson power divider is solved, meanwhile, the function of equal power distribution is achieved, and the compact Wilkinson power divider is suitable for PCB-level applicationsand integrated circuit applications.

The invention relates to a broadband one-to-five power divider / synthesizer for a hybrid circuit. According to the broadband one-to-five power divider / synthesizer, a circuit board is arranged in an aluminum shielding box; the top layer of the circuit board comprises an input port circuit, a transmission line circuit, five output port circuits and a large-area grounding circuit; the middle of the circuit board is a dielectric layer; the bottom layer of the circuit board comprises a transmission line circuit and a large-area grounding circuit; and a transmission line circuit comprises a one-to-two non-equally-divided power divider with a power ratio of 3: 2, a one-to-three power divider and a one-to-two power divider, wherein the output impedance of the one-to-two non-equally-divided power divider is 40.8 ohm and 61.2 ohm, and the one-to-two non-equally-divided power divider is separately connected with the one-to-three power divider and the one-to-two power divider. According to the invention, the transmission line circuit adopts two different forms of conventional coplanar waveguide and grounded coplanar waveguide, and various hybrid circuits are formed through different combination modes. By controlling three variables, namely transmission line width, transmission line length and slot width of the coplanar waveguide, the impedance, amplitude and phase of each circuit section in the circuit are respectively designed on the basis of overall design, and the indexes of low loss, equal output power, high isolation, high phase consistency, larger power bearing and the like of the broadband one-to-five power divider are realized.

The invention provides a novel millimeter wave waveguide radial power synthesis circuit. According to the invention, eight rectangular waveguide Y branches are utilized for integrating eight fan-shaped waveguide based power combiner arranged in radial direction into one. Compared with a traditional round waveguide radial structure based power combiner, the amplitude and phase consistence of branch ports is better. Besides, the circuit has characteristics of small size and wide frequency band and can be used for meeting requirements for millimeter wave multi-channel high-efficient high power synthesis.

The invention discloses a millimeter wave multichannel receiving-transmitting circuit module and power division network high density integrated circuit, and provides the high density integrated circuit with compact routing, low frequency control, and a power supply which does not take up spaces of chip and network layers. According to a technical scheme disclosed by the invention: a chip attachment interface of the multichannel receiving-transmitting circuit module, and a power division network are positioned on a same layer; one-to-two power dividers are adopted to carry out rectangle arraying on mirror symmetrical two-channel receiving-transmitting circuit modules, wherein the attachment interfaces of an amplifier chip and a phase shifter chip are integrated with the power division network to a same medium layer, thereby finishing transmission of radio frequency signals; a radio frequency port and a low frequency port are connected to an antenna unit and a wave controller via an elastic touch manner; and low frequency control pins of the amplifier chip and the phase shifter chip located on the attachment interfaces, and the pins of the power supply are connected with corresponding low frequency control pads (4) and power supply pads (5) on a medium substrate via a gold wire bonding manner, and are arranged around the medium substrate.

The invention discloses a compact linear polarization tracker, and relates to the technical field of satellite communication antennas. The tracker comprises an equiphase orthogonal mode coupler, a rotating orthogonal mode coupler, an L-shaped waveguide rotating joint and a stepping motor drive assembly; the L-shaped waveguide rotating joint comprises a moving waveguide with a gear arranged at one end and a waveguide with a base, and a miniature bearing cavity is machined on one corner of a mounting flange of the waveguide with the seat; the stepping motor drive assembly comprises two pinions and a transmission rod, the pinions are installed on the two sides of the miniature bearing cavity respectively through the transmission rod, one of the pinions is meshed with a drive gear, and the other one of the pinions is meshed with the gear of the moving waveguide of the L-shaped waveguide rotating joint. According to the compact linear polarization tracker, the stepping motor drive assembly drives the rotating orthogonal mode coupler to rotate around the axis of the rotating orthogonal mode coupler by 360 degrees, it is guaranteed that the electric field direction of a straight-through port of the rotating orthogonal mode coupler is matched with the electric field direction in a public port of the equiphase orthogonal mode coupler at a certain angle, and therefore the linear polarization tracking capacity is achieved.

The invention relates to the technical field of simulation systems. The invention discloses a method for improving radio frequency semi-physical simulation broadband signal angle simulation precision.According to the method, an angle simulation precision system is adopted; the system comprises a signal simulation unit, an antenna array feed channel unit and a measurement unit, the signal simulation unit is composed of a signal resolving module, an intermediate frequency generation module and a radio frequency generation module and used for simulating and generating broadband radio frequency signals for simulation, and the amplitude and phase of the signals can be controlled according to needs; an antenna array feed channel is composed of a power amplifier, a switch matrix, a radio frequency cable and the like, and is used for transmitting the broadband signals generated by the signal simulation unit to different radiation positions of the antenna array. By optimizing the radio frequency link structure of a traditional radio frequency simulation system, digital amplitude and phase calibration of radar signals under the broadband condition is achieved, operability is good, efficiency is high, and the radio frequency semi-physical simulation broadband signal angle simulation precision can be remarkably improved.

The present invention belongs to the back-cavity antenna design field and provides a low-frequency broadband high-efficiency low-profile back-cavity antenna. The objective of the invention is to solve problems in the prior art. According to the low-frequency broadband high-efficiency low-profile back-cavity antenna of the invention, a bow tie-shaped dipole and a feed Balun are arranged in a reflection cavity; the root portion of the feed Balun is connected with the bottom end surface of the reflection cavity; the top end of the feed Balun is connected with the feed end surface of the tie-shaped dipole; the other end surface of the tie-shaped dipole is connected with an H-shaped medium pull rod; the cavity connection end of the feed Balun is a connection port which is connected with the bottom end surface of the reflection cavity; the end surface of the cavity connection end of the feed Balun is parallel to the bottom surface of the reflection cavity; the dipole connection end of the feed Balun is a connection end which is infinitely closed to the feed end of the tie-shaped dipole; the end surface of the dipole connection end of the feed Balun is parallel to the bottom surface of the reflection cavity; and two ends of the H-shaped medium pull rod are respectively connected with two opposite edges of the opening end surface of the reflection cavity.

The invention provides an ultra wide band bridge based on a thick film manufacturing technology. The ultra wide band bridge comprises a thick film circuit substrate, a coaxial cable, a magnetic core and a capacitor. The ultra wide band bridge is externally provided with three mutually connected ports P1, P2 and P3, wherein the port P1 and the port P3 are two radio frequency ports connected to a resistor power distribution circuit and the port P2 is connected to the unbalanced end of a Balun. When signals are transmitted in a non-inverting mode, the port P1 serves as an input port, and after resistor power distribution, partial power is coupled to the port P3 to be output and partial power is directly output through the port P2. When the signals are transmitted in an inverting mode, the port P2 serves as the input port, the signals are converted by the Balun from being unbalanced to being balanced, two routes of signals which are equal in amplitude and opposite in phase are obtained at the balanced end, the two routes of signals are offset at the port P3 through power distribution circuits respectively, signal isolation is achieved for the port P3, and partial power is directly output through the port P1. By the adoption of the ultra wide band bridge based on the thick film manufacturing technology, the applicable frequency of the directional bridge based on the Balun and the resistor power distribution circuit can be improved to be in a millimeter wave band, a larger working bandwidth can be realized, and the ultra wide band bridge is simple in structure and convenient to integrate.

The invention belongs to the technical field of microwave communication, and particularly relates to an E-plane waveguide directional coupler and a 16-way waveguide power divider applying the coupler. The coupler comprises a first rectangular waveguide and a second rectangular waveguide which are constructed by E-plane coupling; and a ladder-shaped section for realizing a broadband phase supplementation function is arranged on the second rectangular waveguide, so that the low-amplitude volatility of each output port of a power divider with a high power division rate can be ensured. The 16-way waveguide power divider applying the coupler comprises two groups of waveguide E-plane power dividers, wherein a first E-plane waveguide directional coupler is arranged between the last-stage E-T branch waveguide of the first waveguide E-plane power divider and the previous three stages of power dividing networks, and a second E-plane waveguide directional coupler is arranged between two groups of waveguide E-plane power dividers, so that the amplitude uniformity and phase uniformity of the 16-way power divider can be effectively improved, the problem of large amplitude fluctuation of the power divider with a large power division rate can be synchronously solved, and a broadband designing requirement can be realized.

The invention discloses a broadband and wide-angle dual-circular polarization spaceborne antenna. The antenna is composed of two linear polarization double-slot Vivaldi antennas which are arranged ina crossed manner; two conventional Vivaldi antennas arranged side by side are combined together so as to form the linear polarization double-slot Vivaldi antenna; conductors of the antenna which are located at the center positions of the double-slot antennas partially intersect with each other; two sides of a dielectric plate are printed with metal plates, so that one Vivaldi antenna can be formed; an exponentially-graded metal patch is adopted as a radiating unit of the Vivaldi antenna; uniformly-spaced rectangular grids are designed at the side wings of the exponentially-graded metal patch;the direct-through port and coupling port of a 3dB directional coupler are respectively connected with the terminal open-circuited microstrips of the two double-slot Vivaldi antennas which are arranged in a crossed manner through microstrip power dividers; and the phase difference of two paths of signals is 90 degrees, so that circular polarization can be achieved. The antenna of the present invention can achieve a broadband and wide-angle dual-circular polarization characteristic and has the advantages of small size and light weight; the antenna can be produced in a batched manner with a printed circuit technology; and the antenna can be integrated with an active device and a circuit, so that a single module can be formed.

The invention discloses a Ku-frequency-range four-path radial waveguide power combiner which comprises a body, a base, a cover board and a probe. Four first waveguide ports are equidistantly arranged on the base in a circumferential direction. The top surface cover of the base is arranged on the base so that a first waveguide chamber is formed between the body and the base and the first waveguide ports can be communicated with the first waveguide chamber. The cover board covers the bottom surface of the body so that a second waveguide chamber is formed between the body and the cover board. The cover board is provided with a second waveguide port which is communicated with the second waveguide chamber. The bottom end of the probe is fixedly connected with the top surface of the base, and the bottom end successively penetrates through the first waveguide chamber and a central through hole on the body and extends into the second waveguide chamber. The probe is provided with a multi-step impedance conversion structure. The first waveguide ports and the second waveguide port are BJ140 standard waveguide ports. The Ku-frequency-range four-path radial waveguide power combiner has advantages of wide working frequency band, small insertion loss, high amplitude phase consistency, etc.

The invention provides a "V"-shaped radar radome structure and a preparation method thereof. The radome structure is obtained by co-curing of an antenna, a skin and a filling core layer, the skin andthe filling core layer are adhered by using an adhesive layer so as to form the radome, and the antenna and the filling core layer are adhered by using the adhesive layer and wrapped in the radome. The influence of multilayer reflection interference of the conventional interlayer radome surface can be weakened by the integral design of the radome and the antenna. Besides, compared with the multilayer skin core layer structure, only one skin is required, the wave permeability can be enhanced by the ultrathin skin design and the error of aiming can be greatly reduced. Meanwhile, the antenna pattern and phase consistency can be enhanced, and the problems of reduction of the wave permeability and pattern distortion under the broadband condition of the "V"-shaped radome can be solved, and the wave permeability, the pattern and the phase consistency of the "V"-shaped radome are enabled to meet the working requirements of the radar antenna.

The invention discloses a three-dimensional packaged surface antenna capable of seam phase calibration and relates to a horn antenna. The antenna comprises a metallized vertical via hole feeder line (1), a horn antenna (2) and seams (3), which are integrated on a medium substrate (4), the medium substrate (4) is arranged on the uppermost surface of a three-dimensional package (5), one end of the metallized vertical vial hole feeder line (1) is connected with an internal circuit (8), the horn antenna (2) is composed of a bottom metal plane (6), a top metal plane (9) and a metallized via hole side wall (11), a plurality of seams (3) are arranged in the bottom metal plane (6) and the top metal plane (9), and several sub-horns (16) are formed in the substrate integrated waveguide horn antenna (2) by the seams (3), one ends of the seams (3) face the short-circuit side (15), and the other ends of the seams (3) are arranged on an antenna aperture surface (12). Electromagnetic wave energy in the antenna can reach the antenna aperture surface (12) by the same phase. By the antenna, antenna aperture efficiency and gains can be improved.

Disclosed is a microwave photonics based multi-channel signal transmission system for an aperture synthesis radiometer. The system comprises multi-channel receiving front ends, multi-channel optical transmitters, multi-channel optical fibers and optical receivers. The multi-channel receiving front ends receive multi-channel radio frequency microwave radiation signals through antennas, and then amplify the received signals through low-noise amplification modules. The multi-channel optical transmitters modulate the amplified radio frequency signals to light, light signals are transmitted from all the optical transmitters to the optical receivers through the multi-channel optical fibers, then the optical receivers convert the light signals into radio frequency signals to be outputted, and transmission of the multi-channel radio frequency signals of the aperture synthesis microwave radiometer is completed. By adoption of microwave photonics technology, the radio frequency signals of the distributed receiving front ends of the aperture synthesis microwave radiometer are transmitted, amplitude and phase congruency of multi-channel radio frequency transmission are improved greatly. The method is simple to implement and high in reliability, and a critical foundation is laid to future application of the aperture synthesis microwave radiometer.