58results about How to "Insensitive to temperature changes" patented technology

The invention relates to the technical field of radar, in particular to a millimeter-wave quasi-optical integrated dielectric lens antenna and an array thereof. The array consists of a microstrip integrated antenna, a dielectric lens, an objective lens, an array base, a reflecting mirror, a protective cover and a beam transfer switch; one end face of the dielectric lens is a hemisphere or an ellipsoid, while the other end face is a cylindrical section; the microstrip integrated antenna is generated by an dielectric substrate, the front surface of the dielectric substrate is closely adhered tothe cylindrical section of the dielectric lens and serves as a feed source, and the back surface is grounded; the hemispherical or ellipsoidal end face of the dielectric lens is an antenna radiating surface; the length of the cylindrical part of the dielectric lens can be changed; the antenna array is arranged into a linear array or an area array; the array base and the reflecting mirror have conical quasi-optical reflecting mirror surfaces; the focus of the objective lens of the linear array or the area array aligns with the central line of the dielectric lens; the protective cover is arranged outside; and the antenna array is controlled by the beam transfer switch. The antenna structure has strong shock resistance and dust prevention, and is suitable for millimeter-wave radars for planes, automobiles and ships, and receiving / emitting sensing of communication equipment.

A tunable micro-lens and micro-lens array for use in optical communications are disclosed. The micro-lens uses thermo optical material and a temperature controller to adjust the temperature and, hence, the index of refraction of the thermo optical material. In one embodiment, a single temperature controller is used to maintain an array of micro-lenses at a desired temperature. In an alternate embodiment, the individual lenses in an array are separately tunable. The invention may be used with either 2D or 3D lenses, and is well suited for use with existing planar lightwave circuit (PLC) technology.

This invention provides a radiation dosimeter and new method of operation which comprise two types of the metal-oxide-semiconductor field-effect transistor (MOSFET) circuits allowing to amplify the threshold voltage changes due to radiation and provide temperature compensation. The first type dosimeter is a radiation integrated circuit (RADIC) which includes two radiation field-effect transistors (RADFET) and two MOSFETs, integrated into the same substrate. The second type of radiation circuit includes two RADFETs, integrated into the same substrate, and two resistors. The amplification of the threshold voltage change is achieved by using amplification principles of an MOSFET inverter. In both cases, under the ionizing irradiation, the gate of first RADFET is forward biased and the gate of second RADFET is biased off. In the reading mode the amplified differential threshold voltage change is measured. The increased radiation sensitivity allows to measure of the milli-rad doses. The temperature effect and drift is substantially eliminated. These radiation integrated circuits can be used as a personal dosimeter in the nuclear, industrial and medical fields.

The invention relates to a SiGe bipolar complementary metal oxide semiconductor (BiCMOS) radio-frequency power amplifier. The amplifier comprises a first-stage pre-amplification transistor, a second-stage power amplification transistor, a first-stage biasing circuit, a second-stage biasing circuit, an input matching network and an impedance conversion network. The circuit structure of the invention consists of a first-stage pre-amplification circuit and a second-stage power amplification circuit which are connected with each other through a coupling capacitor. The first-stage pre-amplification transistor is a standard SiGe transistor, and the linearity of the circuit is enhanced by a remote control (RC) serial feedback circuit; and the second-stage power amplification transistor is a high-voltage SiGe transistor and can reach relatively high output power. Both the first biasing circuit and the second biasing circuit have bipolar transistor current mirror structures, and temperature stability is enhanced by temperature negative feedback technology. The amplifier has high linearity and relatively high output power.