44results about How to "Large return loss" patented technology

The invention discloses a substrate integrated waveguide leaky-wave antenna with a big circular polarization beam scanning range, belongs to the field of microwave antenna engineering, and solves a problem that a conventional circular polarization leaky-wave antenna is small in circular polarization beam scanning range. The antenna is of a three-layer structure, wherein the top and the bottom are metal layers, and the central part is a dielectric base material layer. The top metal layer and the bottom metal layer are electrically connected through two rows of metalized via holes, and the top metal layer forms a microstrip, a substrate integrated waveguide converter and N antenna units through etching. Each antenna unit comprises one longitudinal seam and a pair of lateral seams, and the longitudinal seam and the lateral seam pair respectively provide the loading of parallel capacitance and series inductance, can achieve the inhibition of the stop band of the leaky-wave antenna, and achieve the backward, lateral and forwarding continuous scanning of a beam. The longitudinal seam and the lateral seam pair also respectively provide independent controllable lateral polarization and longitudinal polarization radiation, thereby achieving the big circular polarization beam scanning range.

The invention discloses a large-mode-area single-mode fiber connector and a manufacture method. The large-mode-area single-mode fiber connector comprises an insertion pin; a connecting and fixing head is arranged at the periphery of the insertion pin; a single-mode fiber is formed in the center hole of the insertion pin; the single-mode fiber is fused with a graded-refractive-index lens, wherein the graded-refractive-index lens is made by carrying out thermal diffusion on a step-type multimode fiber; and a color ring is formed on a rubber tail sleeve of the single-mode fiber. The manufacture method of the large-mode-area single-mode fiber connector comprises the following steps of: carrying out thermal diffusion on the step-type multimode fiber so as to achieve the element doping of a fiber core, and forming the graded-refractive-index lens with a refractive index reducing outwards along the radial direction; fusing the graded-refractive-index lens with the single-mode fiber, cutting the graded-refractive-index lens and fixedly connecting the graded-refractive-index lens into the center hole of the insertion pin, aligning the outer end of the graded-refractive-index lens with the end face of the insertion, grinding and polishing the end face of the insertion pin; and printing the color ring on the rubber tail sleeve, and configuring the connecting and fixing head for the insertion pin. The large-mode-area single-mode fiber connector and the manufacture method have the advantages that: the large-mode-area single-mode fiber connector is simple in structure and easy to manufacture, the end face of the large-mode-area single-mode fiber connector is easily ensured to be clean, the light-passing area is large, and the matching connection with the traditional other fiber movable connectors can be achieved.

The invention relates to a 2*2MEMS optical switch based on a double optical fiber elliptical light spot collimator. The optical switch is characterized in that: (1) the optical switch is formed by coupling a pair of the double optical fiber elliptical light spot collimators with an MEMS micro-mirror; (2) a beam waist light spot of an exit light beam of the double optical fiber elliptical light spot collimator is an elliptical light spot, that is, the radii of the light spots in two vertical directions are unequal; (3) a collimating lens of the optical fiber collimator comprises a cylindrical surface, and a circular light spot is changed into the elliptical light spot; (4) the surface of the collimating lens is plated with an anti-reflection film to increase return loss; (5) the elliptical light spot collimator is a double optical fiber collimator, and an input optical fiber is a double optical fiber; (6) the MEMS micro-mirror is an MEMS comb drive actuated micro-mirror; and (7) the MEMS micro-mirror is arranged at the beam waist of the exit light beam of the elliptical light spot collimator, and the drive direction corresponds with the minor axis of the light spot. In the optical switch, the requirement of the 2*2 optical switch for the MEMS micro-mirror drive stroke can be greatly reduced, and the stroke of microns can immediately obtain sufficiently low optical signal crosstalk.

The invention discloses a narrow-band difference band-pass filter based on a terminal short circuit self-coupling annular resonator. The narrow-band difference band-pass filter comprises a terminal short circuit self-coupling annular resonator and two coupling micro band lines. Micro band line design with distribution parameters is adopted. The narrow-band difference band-pass filter has the advantages of light weight, high reliability, excellent property, good temperature stability, large-scale production, low cost, and the like, is wide in application prospect in radar of different frequency bands, communication and future high-velocity data wireless communication, and can be particularly used in corresponding systems with harsh requirements on weight, property and reliability.

The invention discloses an electronically-controlled adjustable optical attenuator. On the basis of the microfluidic technology, a sandwich structure is adopted; the first layer is a cover plate (1), an outlet (10) for a power line (9) is left, and piezoelectric ceramic (6) is embedded in an inner groove (12), and the piezoelectric ceramic (6) is bonded with the cover plate (1); the second layer is a square transparent dielectric layer (2) and comprises a microfluidic channel (3) on the diagonal line, an incident fiber collimator (4), an emergent light fiber collimator (5), the piezoelectric ceramic (6), an insulated piston sheet (7) bonded with the piezoelectric ceramic together, a liquid storage pipe (8) and the power line (9), the upper end of the microfluidic channel (3) is sealed with air by using an elastic thin film, the other end is filled with liquid and communicated with the liquid storage pipe (8), and the liquid refractive index is the same as or similar with that of the square transparent dielectric layer (2); and the third layer is a base (11). The piezoelectric ceramic is controlled to be extended and retracted by voltage, the matching liquid in the microfluidic channel (3) is driven to flow, the position of the matching liquid in the microfluidic channel (3) is controlled, the light intensity coupling efficiency between two fiber collimators is thus mediated, and controllable attenuation adjustment on the light is realized.

The invention discloses a 5G broadband Wilkinson power divider, and relates to the technical field of microwave transmission devices. The 5G broadband Wilkinson power divider positioned on a dielectric layer comprises an input port and first and second output ports arranged in the dielectric layer, an input and output matched first branch line is arranged between the input port and the first output port, an input and output matched second branch line is arranged between the input port and the second output port, and first, second and third isolating resistors are arranged successively along the signal transmission direction between the first and second branch lines. The Wilkinson power divider works in the frequency band of 1.45GHz-5.35GHz, the bandwidth of the Wilkinson power divider canbe broadened effectively, and 5G work frequency band can be covered.

The invention relates to a multichannel 2x2 photoswitch. A relay is inlaid in a bottom box; plug holes are respectively formed in two opposite side surfaces of the bottom box; an N-core optical collimator is fixedly arranged in each plug hole; N can be 4, 8, 12 or 16; and the central axes of the collimators on the two sides of the bottom box are superposed to each other. The rear end of a swinging plate hinged to the relay is positioned above a coil; a cantilever arm is fixed at the front end of the swinging plate; and n=N/4 prisms are fixedly arranged at the front end of the cantilever arm. When the multichannel 2x2 photoswitch is in an initial state, the prisms are positioned below light paths of the collimators, and light paths of the collimators at an inputting end and an outputting end are communicated to each other directly. When the relay is electrified, the swinging plate is raised, the prisms on the cantilever arms are placed in the light paths of the optical collimators, outputting light of the optical collimator of the inputting end is refracted and reflected by the prisms and then enters another light path of the outputting end, and each prism can switch 4 light paths. Each optical collimator is inserted in a plug tube fixedly connected to the corresponding plug hole and is fixed, and a plug sleeve sleeves each optical collimator so as to protect the optical collimator. The bottom box is closed by a cover plate, various seams are sealed in a metalized manner, and the bottom box is filled with nitrogen. The multichannel 2x2 photoswitch is simple in structure, low in loss, convenient to adjust, high in precision and long in service life.

The invention relates to a cable, particularly relates to a radio frequency coaxial cable, and belongs to the technical field of cable manufacturing. The radio frequency coaxial cable comprises an internal conductor, insulating layers, an external conductor and a sheath. The internal conductor is a silver-plated copper wire. The conductor is extruded by the insulating layers. There are two insulating layers, wherein the internal layer is solid perfluorinated ethylene-propylene, and the external layer is solid polyethylene. The external diameter of the insulating layers is 1.90-5.08cm. The insulating layers are longitudinally wrapped by the aluminum foil external conductor which is provided with, from inside to outside, a copper wire braiding shielding layer, a copper tape shielding layer and a copper wire braiding shielding layer. The external copper wire braiding shielding layer is extruded by the sheath. The cable is excellent in shielding performance, wide in use frequency band, stable in performance and attenuation is low.

An integrated system for optical fiber testing equipment is provided with an optical switch, three sets of equipment connection ports and two sets of sample connection ports. electrical connection. Each group of device connection ports is composed of a device data input lead fiber and a device data output lead fiber, and one end of the device data input lead fiber and the device data output lead fiber is respectively connected to the optical switch. Each group of sample connection ports is composed of a sample test signal input lead fiber and a sample test signal output lead fiber, and one end of the sample test signal input lead fiber and the sample test signal output lead fiber is respectively connected to the optical switch. Through the reasonable integration of resources through the optical path switching mode, multiple instruments can be connected to each other, and the optical fiber is connected at one time, and the tests of different optical fiber indicators are completed successively, which can improve the work efficiency of operators and the use efficiency of test equipment.