摘要:
An apparatus and method for determining a current state of charge of a battery are disclosed. The apparatus includes a battery signal developer, a threshold developer, a comparator, and a bi-directional integrating device. The battery signal developer receives a battery voltage and develops a corresponding battery signal. The threshold developer receives an integration result signal based on an integration value representative of the current state of charge of the battery, and develops a threshold signal based on the integration value. The comparator provides first and second comparison signals, respectively, when the battery signal magnitude is greater than and less than the threshold signal magnitude. The integrating device accumulates the integration value and receives a comparison result signal based on the first and second comparison signals. The integrating device adjusts the integration value in first and second opposite directions, respectively, when the first and second comparison signals are being provided by the comparator to reflect both increases and decreases in the current state of charge of the battery.
摘要:
Apparatus is disclosed for controlling the speed of an electric motor by selectively connecting a field weakening resistor across the field winding of an electric motor. A first means is provided for comparing the field voltage to a fixed reference voltage and for generating a first signal in response to the field voltage falling below a first predetermined value and a second signal in response to the field voltage rising above a second predetermined value. A second means responsive to the first and second signals is provided for selectively connecting a field weakening resistor across the field winding of the motor in response to the field voltage falling below the first predetermined value. The second means responsive also disconnects the field weakening resistor in response to the field voltage rising above the second predetermined value.
摘要:
A wafer antenna comprises a wafer substrate, a plurality of antenna elements integrated on the wafer substrate for radiating and receiving a radio frequency signal, an electrical connection integrated on the wafer substrate; a feed network integrated on the wafer substrate for distributing the RF signal from the electrical connection to the antenna elements and from the antenna elements to the electrical connection, and a plurality of tunable dielectric phase shifters integrated on the wafer substrate with each of the tunable dielectric phase shifters coupled to a corresponding one of the antenna elements and controlling the phase of the RF signal coupled to the corresponding one of the antenna elements.
摘要:
A capacitive element includes two or more voltage-variable capacitors (varactors). The varactors are configured so that they are coupled in series with respect to an applied AC signal and are coupled in parallel with respect to an applied DC bias voltage. The effective capacitance of the overall capacitive element can be tuned by varying the DC bias voltage.
摘要:
A quasi-optical power combining array provides broadband, well heat sinked performance by means of coupling an array of parallel slotline transition modules between a input waveguide and an output waveguide. Each slotline transition module is comprised of a heat sinked ceramic substrate upon which a pair of tapered slot transitions is defined, each of which lead to a quasi-optical element such as an amplifier, which in turn is coupled to a corresponding pair of tapered slot transitions leading to the output waveguide. Each slotline module is symmetrically formed to maximize input and output tuning and selectively balanced operation.
摘要:
A circuit topology is configured to flatten out a phase- and amplitude-response over a specified range of frequencies. The circuit topology also provides a large cumulative phase-shift. In one embodiment, the circuit topology cascades a plurality of all-pass sections, with the center-frequencies of each all-pass section staggered to create a substantially flat phase-response over a frequency range. Further, in one embodiment the plurality of all-pass sections has at least one all-pass section that is different from another all-pass section. Each all-pass section includes a tunable capacitor and has a center-frequency that can be varied by electronically tuning the capacitor. Each center frequency is selected to obtain substantially constant amplitude and phase response over a desired frequency range and capacitance tuning range.
摘要:
This invention exploits the synchronization properties of coupled, nonlinear oscillators arrays to perform power combining, beam steering, and beam shaping. This architecture utilizes interactions between nonlinear active elements to generate beam patterns. A nonlinear array integrates the signal processing concurrently with the transduction of the signal. This architecture differs fundamentally from passive transducer arrays in three ways: 1) the unit cells are nonlinear, 2) the array purposely couples the unit cells together, and 3) the signal processing (beam steering and shaping) is done via dynamic interactions between unit cells. The architecture extends to both 1- and 2-dimensional arrays.
摘要:
A microelectromechanical switch is disclosed comprising a conductor, a dielectric layer disposed on the conductor, a metal cap disposed on the dielectric layer and a bridge disposed proximate to the metal cap such that an electrical potential applied between the bridge and conductor causes the bridge to deform and contact the metal cap.
摘要:
An array of coupled microwave oscillators operate at equally spaced output frequencies to produce a train of high-power RF pulses. Each oscillator is embedded in a printed planar radiating structure so that they form a classical antenna array. The oscillators are coupled through weak radiative interactions and by adjusting the frequencies of the oscillators so that adjacent devices operate at equally spaced frequencies, the output from the array is a frequency spectrum of equally spaced pulses. The pulses have a pulse repetition rate which is determined by the frequency spacing and the pulse duration and peak power are a function of the square of the number of oscillators in the array. In addition, the signal scans repetitively through space above the array.
摘要:
A high-powered, solid state microwave and millimeter wave, power combiner and divider is provided by using a plurality of radially oriented tapered slotline cards disposed in a center cylindrical coaxial section between its inner and outer conductors. The cylindrical coaxial section in turn is coupled to a conical input coaxial section that couples and distributes the input signal among the plurality of cards, and an output coaxial section that combines the output signal from the plurality of cards to an output coaxial terminal. The device is compact with broadband performance and provides a natural heat sink for a plurality of lower powered devices, which enables the power combiner to use a large number of lower powered devices to meet larger power requirements.