38results about How to "Small transmission attenuation" patented technology

The invention discloses an optical sensor capable of effectively detecting produced electric arc light and converting the electric arc light into an electric signal to be output when an outgoing wire or a bus of a switch cabinet has a short-circuit fault. The optical sensor comprises a light acquisition lens, a photoelectric converter and a plastic optical fiber, wherein two ends of the plastic optical fiber are provided with ST connectors, and the plastic optical fiber is connected with the light acquisition lens and the photoelectric converter through the ST connectors. Due to the fact that the light acquisition lens is a passive device, the light acquisition lens is connected with the active photovoltaic conversion portion through the plastic optical fiber, and a primary device of the switch cabinet is not influenced. The light acquisition lens only acquires light information of specific wave bands in arc light and can effectively filter interference of other light sources. An electrical signal only existing at the photovoltaic conversion portion of the sensor, the rest is light signals, and electromagnetic interference produced during actions of the switch cabinet can be effectively avoided. By adopting anti-static design achieved by a transient diode, the device reliability is improved, and the optical sensor can adapt to various assembling and usage environments.

The invention discloses an IEEE (Institute of Electrical and Electronic Engineers) 802.15.4g standard-based wireless monitoring communication protocol, and belongs to the technical field of embedded wireless monitoring. IEEE802.15.4g is a standard of a physical layer named SUN, which is established by Institute of Electrical and Electronic Engineers (IEEE) in recent two years, the physical layer is supplemented on the basis of an IEEE802.15.4 standard, and the IEEE802.15.4g standard is particularly suitable for battery powered infrastructure sensor networks which have ultralow power consumption, remote transmission and excellent anti-noise performance. Although IEEE802 is still standardized at present, a draft scale has been determined basically, so the set of standard is necessarily tracked and studied timely, and based on the underlying standard, a set of ultralow power consumption wireless upper-layer communication protocol applied to the field of smart grid monitoring is designed and developed. The protocol aims at a star network topological structure, working method steps for a network coordinator node and a sensor node are respectively designed, and the protocol has the characteristics of low velocity, ultralow power consumption, low complexity and the like.

The invention discloses a circular waveguide antenna feeder antenna system which comprises an antenna, a circular and flexible waveguide, an upper sealing section, a circular waveguide bend, a parasitic mode filter, a circular waveguide tube, a polarization expansion joint, a polarization rotating joint, a convertor, a polarization separator and a waveguide bend. The antenna, the circular and flexible waveguide, the upper sealing section, the circular waveguide bend, the parasitic mode filter, the circular waveguide tube, the polarization expansion joint, the polarization rotating joint, the convertor, the polarization separator and the waveguide bend are connected in sequence. The polarization separator and the waveguide bend are respectively connected with a rectangular flexible waveguide, a rectangular waveguide, a rectangular waveguide sealing section and a step convertor. As the circular waveguide is adopted in the circular waveguide antenna feeder antenna system to transmit information, the circular waveguide antenna feeder antenna system has the advantages that steering is convenient, information receiving is facilitated, power capacity for microwave transmission is larger and transmission attenuation is less.

The invention discloses a low-attenuation signal transmission cable. One of seven tin-coated copper wires is arranged at the center position, and other six tin-coated copper wires are stranded and arranged at the outer surface of the central tin-coated copper wire; a steel layer covers the outer surface of a first steel layer, and a second steel layer covers the outer surface of the steel layer; the first steel layer and the inner surface of the steel layer are connected in a sealed manner through a first alloy layer, and the second steel layer and the outer surface of the steel layer are connected in a sealed manner through a second alloy layer; an outer protection layer covers the outer surface of the second steel layer; and the second alloy layer is composed of 25% copper, 69% iron, 3% molybdenum, 2% chromium and 1% carbon. The low-attenuation signal transmission cable is capable of absorbing a magnetic field in an electromagnetic field, and the shielding performance of an electric field is improved after two times of absorption.

The invention provides a detection method and device for the stable plug-in state of a plug-in card, and equipment. The method comprises the following steps that: a single board receives a differential signal from the plug-in card through a differential pair pin between the plug-in card and the single board; the single board determines whether the plug-in card which is plugged into the single board at present is under the stable plug-in state or not according to a judgment result which shows whether the quality of the differential signal meets a preset plug-in state or not, wherein the plug-instate condition is that alternating current impedance and direct current impedance between the single board and the plug-in card meet signal transmission impedance requirements. By use of the methodprovided by the invention, the accuracy of the stable plug-in detection of the stable plug-in card is greatly improved, in addition, when a serdes signal is transmitted between the single board and the stable plug-in card, serdes signal transmission quality can be guaranteed, serdes signal transmission attenuation is lowered, and meanwhile, the transmission quality of a direct current signal whendirect current transmission is carried out between boards can be guaranteed.

The invention discloses an anti-electromagnetic interference railway digital signal cable. The cable comprises 2-20 conductive wire groups wrapped by polyester bands. Each conductive wire group comprises four stranded single wire formed by stranding of seven tin-coated copper wires. The outer surface of the stranded single wire is provided with an inner insulating layer. A covering layer covers the outer surfaces of the 2-20 conductive wire groups. A first copper layer covers the outer surface of the inner insulating layer. A steel layer covers the outer surface of the first copper layer. A second copper layer covers the outer surface of the steel layer. The first copper layer and the inner surface of the steel layer are connected in a sealed manner through a first alloy layer, and a second copper layer and the outer surface of the steel layer are connected in a sealed manner through a second alloy layer. An outer protection layer covers the outer surface of the second copper layer. The first alloy layer is composed of 78% copper, 15% iron, 3% molybdenum, 3% chromium and 1% carbon. The anti-electromagnetic interference railway digital signal cable has the advantages that the transmission attenuation of the cable is reduced, and the adaptation and the mechanical force resistance are improved.

The invention discloses a multifunctional track traffic digital signal cable. The multifunctional track traffic digital signal cable is characterized in that a conductive wire group comprises four stranded signal wire formed by stranding of seven tin-coated copper wires, one of the seven tin-coated copper wires is arranged at the center position, and other six tin-coated copper wires are stranded and arranged at the outer surface of the central tin-coated copper wire; a first steel layer and the inner surface of a steel layer are connected in a sealed manner through a first alloy layer, and a second steel layer and the outer surface of the steel layer are connected in a sealed manner through a second alloy layer; an outer protection layer covers the outer surface of the second steel layer; and the second alloy layer is composed of 33% copper, 60% iron, 4% molybdenum, 2.2% chromium and 0.8% carbon. The multifunctional track traffic digital signal cable has the advantages that the transmission attenuation of the cable is reduced, the formability, the extensibility and the electrical conductivity are improved, and the tensile strength and the impact resistance are improved.

The invention relates to the technical field of a RG-6 copper-coated steel coaxial cable fabrication process, in particular to a RG-6 copper-coated steel coaxial cable. The RG-6 copper-coated steel coaxial cable comprises a copper-coated steel conductor, an inner skin layer, a foam layer and an outer skin layer, wherein the raw material for fabricating the inner skin layer comprises the followingconstituents based on parts by weight: 0.3-0.7 part of ethylene-ethylhexyl copolymer and 23-27 parts of low-density polyethylene, the raw material for fabricating the foam layer comprises the following constituents based on parts by weight: 23-27 parts of HDPE 2911, 23-27 parts of HMA, 23-27 parts of low-density polyethylene and 0.3-0.7 of nucleating agent, and the raw material for fabricating theouter skin layer comprises the following constituents based on parts by weight: 0.3-0.7 part of ethylene-ethylhexyl copolymer and 23-27 parts of low-density polyethylene. The fabricated RG-6 copper-coated steel coaxial cable has the advantage of small transmission attenuation, and the signal transmission quality of the coaxial cable is favorably improved.