摘要:
Systems and methods for forming a compact gas sensor include using a lithographically fabricated high Q resonator coupled to at least one of a Gunn diode and an IMPATT diode. The resonator may include a plurality of cavities filled with a sample gas. A detector coupled to the resonator may measure the amplitude of the emitted mm wave radiation.
摘要:
A voltage controlled oscillator comprises a negative resistance, a first inductor, a fixed capacitor, and a frequency control component. The frequency control component comprises at least one varactor and at least a second inductor connected in series with the at least one varactor. A magnitude of an inductance of the second inductor is selected such that the frequency control component has an effective capacitance range larger than a capacitance range of the at least one varactor.
摘要:
An oscillator circuit that includes a voltage source, a resistor, a capacitor, and a nonlinear device. The capacitor and the nonlinear device may be coupled in parallel with one another. The resistor may be coupled in series with the capacitor and the nonlinear device. The voltage source may be coupled in series with the resistor. The voltage source may supply the oscillator circuit with a direct current input signal. The nonlinear device may include an active layer coupled to a first electrode and a second electrode. In response to the direct current input signal, the oscillator circuit may output a spike train including a spike bunch.
摘要:
A frequency synthesizer device provides amplitude control. Using switch circuit operating in a first mode, a charge voltage is applied to an oscillator circuit that an inductive-capacitive (LC) tank circuit. The LC tank circuit has a capacitive element, and an inductive element that is connected to the capacitive element. Using the switch circuit operating in a second mode, the LC tank circuit is enabled to oscillate. Using driver circuits that are response to a voltage applied to the tank circuit, current is reinforced in the LC tank, and the reinforcement is based upon a transconductance gain of the driver circuits. Using a calibration circuit, an amplitude of an output signal from the oscillator circuit is detected. In response to the detected amplitude, the transconductance gain is adjusted by enabling or disabling auxiliary circuits from plurality of auxiliary circuits.
摘要:
A novel and useful oscillator topology demonstrating an improved phase noise performance that exploits the time-variant phase noise model with insights into the phase noise conversion mechanisms. The oscillator is based on enforcing a pseudo-square voltage waveform around an LC tank by increasing the third-harmonic of the fundamental oscillation voltage through an additional impedance peak. Alternatively, the oscillator is based on enforcing clipped oscillation waveform by increasing the second harmonic of the fundamental oscillation voltage through an additional impedance peak. This auxiliary impedance peak is realized by a transformer with moderately coupled resonating windings. As a result, the effective impulse sensitivity function (ISF) decreases thus reducing the oscillator's effective noise factor such that a significant improvement in the oscillator phase noise and power efficiency are achieved.
摘要:
An embodiment of the voltage controlled oscillator is provided. The oscillator comprises a first inductor set, a second inductor set, a second capacitor, a voltage source and a negative resistance element. The inductance of the second inductor set is k times the inductance of the first inductor set. The voltage source applies an ac voltage to the second inductor set. The negative resistance element is coupled to the second inductor set to provide a negative resistance to resonate the second capacitor at the second inductor set.
摘要:
Disclosed herein are embodiments of an LC-type VCO with multiple operational frequency bands having reasonably similar frequency vs. control signal slopes.
摘要:
A voltage controlled oscillator of the present invention comprises a reference voltage generation section 114 for generating a plurality of reference voltage based on a power supply voltage. A first to a third reference voltages Vref1, Vref2, and Vref3 are inputted to a first to a third variable capacitance circuits A, B, and C, respectively, at each one of terminals of each of the first to the third variable capacitance circuits A, B, and C. The first to the third reference voltages Vref1, Vref2, and Vref3 each has a fixed value, and a difference between the first reference voltage Vref1 and the second reference voltage Vref2 and a difference between the second reference voltage Vref2 and the third reference voltage Vref3 represent values different from each other. A control voltage Vt for feedback-controlling an oscillation frequency is inputted to each of the other of the terminals of the variable capacitance element of each of the n variable capacitance circuits such that the control voltage Vt having the same value is inputted to said each of the other of the terminals.
摘要:
A voltage controlled oscillator 100 comprises an inductor circuit including inductors 101, 102; a variable capacitance circuit 110 which includes variable capacitance elements 111, 112 for changing a capacitance value in accordance with a voltage difference between both of two terminals thereof and capacitive elements 113, 114 for cutting a DC component, and which is connected in parallel to the inductor circuit; a negative resistance circuit including cross-coupled oscillating transistors 103, 104; and a time-switched level shift circuit 108 for shifting a reference voltage to be output to two or more levels in accordance with time. A connection point A of the variable capacitance elements is supplied with a control voltage Vt for controlling an oscillation frequency, and connection points B, C of the variable capacitance elements and the capacitive elements are supplied with a reference voltage Vref output from the time-switched level shift circuit 108 via resistors 115, 116.