摘要:
A directional coupler is formed with adjacent edges of its microstrips following curved paths having reversals in curvature such as a series of sine waves or half circles.
摘要:
A system includes a source of electromagnetic energy or power and an amplitude-sensitive circuit. An amplitude-limiting transmission line couples the source to the circuit. The transmission line includes a semiconductor in the field of the transmission line and a light source for illuminating the semiconductor with light responsive to the amplitude from the source. Application of energy or power to the light source illuminates the semiconductor, which produces a plasma. The plasma tends to attenuate the energy or power reaching the circuit.
摘要:
An RF phase shifter includes the cascade of active and passive RF phase shift bits, having different phase increments. The active phase shift bit includes a FET with source and drain. First and second RF single-pole, double throw switches have their common elements coupled to the source and drain, respectively, for selectively connecting one of the in-phase source signals and out-of-phase drain signals to a third switch, and for coupling the non-selected signal to a reference. The third switch outputs the available signal. Additional phase increments may be included to achieve phase shifts or differences other than 180°.
摘要:
A magnetic flux-enhanced control line for a superconducting flux flow transistor (SFFT). The SFFT includes a pair of superconducting electrodes which provide a voltage output, a region of weakened superconductor connecting the electrodes and a control line. The region of weakened superconductor carries a current I.sub.body and the control line carries a current I.sub.Control. The control line further has a portion thereof proximate the weakened region for providing a localized magnetic field through the weakened region as a function of I.sub.Control. The magnetic flux through the weakened region induces vortices therein which have a resistance r.sub.o. The proximate portion of the control line forms a tortuous current path whereby the magnetic flux through the weakened region is increased for increasing r.sub.o so that the output voltage of the transistor is increased without increasing I.sub.Control.
摘要:
A high-temperature superconductor (HT.sub.c S) in a microstrip configurat which is electrically related to a superconducting coupler and which is controlled by a heater disposed over the superconducting microstrip line. This limiter configuration is used in a series configuration with other circuitry and utilizes the low loss characteristics of the HT.sub.c S material and the wide bandwidth characteristics of microstrip. The structure itself is a five layer microstrip geometry which includes a normal metal ground plane; a dielectric substrate disposed on the metal ground plane; a superconducting microstrip transmission disposed on the substrate; a dielectric film layer disposed on the superconducting microstrip; and a heating element disposed on the dielectric film layer and over the superconducting microstrip.
摘要:
A frequency divider circuit includes a master-slave flip-flop having a master flip-flop and a slave flip-flop. The slave flip-flop is connected to the master flip-flop. The master flip-flop includes a first plurality of logic gates and is configured to receive a first clock signal. The slave flip-flop includes a second plurality of logic gates and is configured to receive a second clock signal. The second plurality of logic gates is implemented using single-ended diode-transistor logic (DTL).
摘要:
An antenna structure for solid-state fabrication includes a ground plane comprising a stack of a plurality of planar conductors, each having its broad surfaces adjacent to, but insulated from, adjacent planar conductors. At least one edge of each conductor of the stack is registered with like edges of other conductors to define a discontinuous surface. A radiating element is spaced from the surface. Through vias extend between the conductors of the stack to form a conductive matrix. A feed for the radiating element extends toward, but does not contact, the matrix.
摘要:
A Doppler radar speed measuring module, that is self-contained and handheld, is fabricated on a multilayer PCB (printed circuit board) containing at least one antenna array and electronic circuitry. In one embodiment the antenna array is located on a top side and electronic circuitry is located on a bottom side opposite the antenna, with a ground plane layer sandwiched between the antenna array and the circuitry. The electronic circuitry includes a dielectric resonator stabilized oscillator, a microwave amplifier, a microwave mixer, a microwave coupler, voltage regulators, mechanical switches, and a display to indicate the measured speed of a moving target. The oscillator generates a very stable microwave signal which is split with part of the signal fed to a mixer and part fed to a transmit antenna. In one embodiment plated through vias electrically connect the two sides together. A transmitted signal reflects off of a moving target and is received by a receive antenna. The receive signal is electrically conducted from the receive antenna to the opposite side by plated through vias and is mixed with the oscillator signal to produce a low frequency Doppler beat signal. The Doppler signal is amplified, filtered and digitized by the A/D. A microcontroller is programmed to determine the moving target speed from the Doppler signal frequency, and drive a display to show the result.
摘要:
A remote temperature sensor includes a microwave oscillator which generatesn output signal having a frequency which is proportional to the temperature of the environment in which it is located. The oscillator includes a relatively high transition temperature superconducting (HTSC) ring coupled to a transistor in a plurality of microstrip line oscillator configurations including those of a reaction oscillator, a transmission oscillator, a reflection oscillator and a parallel feedback oscillator. The superconducting ring operates below its transition temperature and in so doing, acts as a high Q resonator whose resonant frequency is proportional to temperature.
摘要:
An ambient condition sensor is embodied in an oscillator which generates an output signal having a frequency which is proportional to the ambient condition of the environment in which it is located. The oscillator includes a ring resonator consisting of a metallic ring located in the output plane of a grounded source gallium arsenide MESFET type transistor oscillator formed on a temperature sensitive dielectric substrate. The circumference of the ring is directly related to the ring resonator's resonant frequency. More particularly, the circumference of the ring is a multiple of the wavelength of the oscillator's output signal. Such a device permits unmanned, remote and inexpensive temperature sensing in places generally unsuited for operator presence.