51results about How to "No dielectric loss" patented technology

The invention discloses an air dielectric cylindrical lens antenna. The air dielectric cylindrical lens antenna comprises a metal disc-shaped parallel plate waveguide, a feed source antenna and arc-shaped metal support plates, wherein the metal disc-shaped parallel plate waveguide comprises an upper metal disc and a lower metal disc, the upper and the lower inner surfaces of the metal disc-shaped parallel plate waveguide are planes or arc-shaped surfaces, a central cavity of the metal disc-shaped parallel plate waveguide forms an air dielectric cylindrical lens, an annular boss is arranged below the edge of the upper disc of the metal disc-shaped parallel plate waveguide, the annular boss is arranged above the edge of the lower disc of the metal disc-shaped parallel plate waveguide, the feed source antenna is arranged between the two annular bosses, the feed source antenna is embedded in an arc-shaped groove between the arc-shaped metal support plates on the edges of the two metal discs, and the arc-shaped metal support plates are connected with the two metal discs through screws. The feed source antenna is a horizontal polarization gradient groove antenna or a horizontal polarization gradient groove antenna array.

The invention discloses a high-isolation small-sized radial power distributor/synthesizer. The high-isolation small-sized radial power distributor/synthesizer comprises a radial power distributor/synthesizer of an inserted resistor diaphragm and a rectangular waveguide-circular waveguide mode conversion structure, wherein the radial power distributor/synthesizer of the inserted resistor diaphragm comprises an input circular waveguide port, an impedance transformation structure and more than one output rectangular waveguide; the three structures are connected in sequence; the rectangular waveguide-circular waveguide mode conversion structure comprises an input rectangular waveguide, a one-into-four power distribution network, a waveguide expansion transition structure and an output circular waveguide which are connected sequentially. The power distributor/synthesizer can realize power multiplexing, wide band, low loss, small size, easy assembly and power distribution/synchronization of port isolation.

The invention provides an ultra-wide band multi-path coaxial power distribution synthesis structure based on a high-odor oval function curve. A coaxial gradual change structure based on the high-odor oval function curve is adopted, an input signal enters a high-odor oval function curve coaxial gradual change structure from an input end coaxial connector, and is distributed onto a circular disc in a uniform-amplitude and same-phase way, multi-path coaxial probes in uniform distribution are led out from the edge of the circular disc to be coupled onto a plurality of independent amplifier assemblies corresponding to the multi-path coaxial probes for respectively carrying out power amplification, each coaxial probe adopts a step cylinder structure with the wider upper part and the narrower lower part, the amplified multi-path signal is synthesized and output through a structure completely identical to a power splitter structure. The ultra-wide band multi-path coaxial power distribution synthesis structure has the advantages that the difficult problem of high-power synthesis of the ultra-wide frequency band is solved, the high-odor oval function curve coaxial gradual change structure is adopted, in addition, the step coupling probe conversion is carried out, the signal energy high-efficiency distribution and synthesis of the ultra-wide frequency band are realized, the structure is compact and symmetrical, the heat radiation performance is good, the high-degree modular design is adopted, the processing and the assembly are simple, and the reliability is high.

A multi-purpose solar energy air conditioner is disclosed. The left and right pressure tanks containing liquid ammonia and installed on heat absorbing plate have upper ports communicated with inlet of condenser whose outlet is communicated with inlet of heat exchanger via pressure reducing valve. The outlet of heat exchanger is communicated to the lower ports of said pressure tanks. The case of heat exchanger is connected via three-way valve to lower port of evaporator. The another way of said three-way valve is linked to water return inlet of solar heat collector. The hot water outlet of said collector is communicated with heat accumulator communicated with vapour tank. Its advantages include simple structure, low cost, long service life and high efficiency.

A mobile terminal antenna employing a metal frame as a radiation body comprises the metal frame, a system floor, a first metal connection strip, a second metal connection strip, a lumped inductor anda coaxial feeding port, wherein the system floor is rectangular, a left side and a right side are long sides, an upper side and a lower side are short sides, the system floor is encircled by the metalframe, a gap exists between the metal frame and the system floor, the metal frame is connected with the first metal connection strip, the second metal connection strip and the system floor, the lumped inductor is welded onto the second metal connection strip, an outer conductor of the coaxial feeding port is welded onto the system floor, and an inner conductor crosses the gap and is welded onto the metal frame. The antenna is of a pure metal structure, no dielectric loss is generated, and high radiation efficiency is achieved; the metal frame is used as the radiation body, a traditional antenna structure is not needed, and the internal space of the mobile terminal is almost not occupied; and the mobile terminal antenna is applicable to various small-size mobile terminals with representative of a mobile phone.

The invention discloses a halogen-free flame-retardant low-pressure packaging material with ultra-low dielectric property and a preparation method thereof. The halogen-free flame-retardant low-pressure packaging material is prepared from dimer acid, dibasic acid, diamine, polyether diamine, difunctional polyphenylene ether, diisocyanate, a halogen-free flame retardant, an antioxidant, a hydrolysisstabilizer, a UV stabilizer, a colorant, phosphoric acid, and dibutytin laurate. The invention also discloses a preparation method of the halogen-free flame-retardant low-pressure packaging materialwith ultra-low dielectric property. The packaging material disclosed by the invention has ultra-low dielectric loss and halogen-free flame retardant performance, and is suitable for electronic components which are manufactured with low-pressure injection molding process and can be applied to the field of high-frequency communication, and especially suitable for the field of fast and efficient packaging of sensitive high-frequency electronic components.

The invention relates to a composite method for modifying a flax fabric via crystal lattice change. The method comprises the following steps: putting the flax fabric into an enclosed container; filling a modification medium; boosting to a modification pressure; releasing pressure momentarily; performing combined treatment of vacuum pumping, high-speed centrifugal rotary traction and microwave radiation, and removing the modification medium to obtain the flax fabric modified via crystal lattice change. The flax fabric modified via crystal lattice change has the advantages of increased pores, lower degree of crystallization and yarn softness, and the size stability, softness, dyeing performance and the like of a product are enhanced; a method for releasing pressure momentarily is adopted, so that the bulkiness and softness of the fabric are enhanced greatly; combined treatment of vacuum pumping, high-speed centrifugal rotary traction and microwave radiation is adopted, so that the quality of the fabric is further enhanced, and the modification efficiency is increased greatly.

The invention discloses a broadband frequency selection surface for planar dual-polarization millimeter waves, belongs to the technical field of antenna engineering, and relates to a dual-polarizationfrequency selection surface. The frequency selection surface is formed by splicing and combining frequency selection surface unit arrays. The frequency selection surface unit is of a metal square annular structure. Each side of the annular structure is provided with two strip-shaped dipoles which extend inwards: a first dipole and a second dipole, wherein the height of the first dipole is largerthan that of the second dipole, the included angles between the dipoles and the corresponding annular structure edges are the same and are not 90 degrees, and the opening directions of acute angles formed by the dipoles and the corresponding annular structure edges are consistent. A traditional annular unit is not suitable for an integrated connection structure and needs to be supported by a medium. A traditional dipole-shaped unit is small in passband width and high in in-band loss. By adopting the deformed square annular unit, the bandwidth similar to that of a traditional annular unit and the lower in-band loss are obtained, and the method can be achieved through metal machining.

The invention discloses a full metal circular polarization and liner polarization 8-shaped wave beam antenna of a millimeter wave. Two antenna radiation units are respectively mounted on two rectangular feed waveguides which are connected or not connected with each other; the two rectangular feed waveguides are connected with a double-T-shaped waveguide splitter; each antenna radiation unit is provided with a cross-shaped coupling gap; a pair of isosceles triangle radiation slots which are distributed in a central symmetry way are formed in the two diagonal line directions and positioned on the upper surface of a rectangular radiation cavity; the rectangular radiation cavity is fixed above the cross-shaped coupling gap; the arm E and the arm H of the double-T-shaped waveguide splitter are input ends; the two side arms are respectively connected with two hollow conducting cavities. According to the antenna disclosed by the invention, the 8-shaped wave beam shape and width are realized by adjusting an angle; full metal can be used for extremely harsh environments, such as low-temperature and high-temperature environments; meanwhile, the full metal circular polarization and liner polarization 8-shaped wave beam antenna of the millimeter wave has the advantages of compact structure, low side lobe and back lobe, wide application range, low requirement for machining precision, easiness in implementation, low cost and the like, and is very suitable for millimeter-wave band.

The invention relates to a compound crystal transition modification method of flax yarn. The flax yarn is arranged in a sealed container, a modification medium is injected in the container, the pressure is increased to the modification pressure, then the pressure is released instantly, vacuumizing, high speed centrifugation rotation traction and microwaves act jointly, the modification medium is removed, and the compound crystal transition modified flax yarn is obtained. The crystal transition modified flax yarn is larger in hole, lower in crystallinity and is soft, and improves the size stability, softness, dyeing property and the like of products. Through the method of releasing the pressure instantly, the fluffiness and softness of the yarn are largely improved. Through the joint action of vacuumizing, high speed centrifugation rotation traction and microwave radiation, the quality of the yarn is further improved, and the modification efficiency is largely improved.

The invention relates to a composite crystal change modification method of cotton/ramie blended fabrics. According to the method, the cotton/ramie blended fabrics are placed in a closed container, a modified medium is added into the container, pressure is raised to modification pressure, then, the pressure is released instantly, then the combined effect of vacuumization, high-speed centrifugal rotation and drafting and microwave is used for removing the modified medium, and therefore composite crystal change and modified cotton/ramie blended fabrics can be obtained. According to the crystal change and modified fabrics, pores are increased, degree of crystallinity is reduced, the fabrics are soft, and size stability, flexibility, dyeing performance and the like of products are improved; the method of pressure instant release is adopted, and therefore the fluffiness and flexibility of the fabrics are improved greatly; the combined effect of vacuumization, high-speed centrifugal rotation and drafting and microwave is adopted, quality of the fabrics is further improved, and modification efficiency is greatly improved.

The invention relates to a composite crystal change modification method of a cotton fabric. According to the method, the cotton fabric is placed in a closed container, a modification medium is added, pressure is raised to modification pressure, then, the pressure is released instantly, the combined effect of vacuumization, high-speed centrifugal rotation and drafting and microwave is used for removing the modified medium, and therefore a composite crystal change and modified cotton fabric can be obtained. According to the crystal change and modified cotton fabric, pores are increased, degree of crystallinity is reduced, the fabric is soft, and size stability, flexibility, dyeing performance and the like of products are improved; the method of pressure instant release is adopted, and the fluffiness and flexibility of the fabric are improved greatly; the combined effect of vacuumization, high-speed centrifugal rotation and drafting and microwave is adopted, therefore, fabric quality is further improved, and modification efficiency is greatly improved.