A transformer based voltage controlled oscillator (VCO) is provided with a primary resonant circuit having a first inductor connected in parallel with a variable first capacitance circuit. A secondary resonant circuit is formed from a second inductor connected in parallel with a variable second capacitance circuit, and also includes a mode control circuit. The mode control circuit controls the direction of current flow through the secondary resonant circuit inductor. The first and second inductors are inductively mutually coupled in either an even mode or an odd mode in response to the mode control circuit. The VCO supplies a first resonant frequency in response to even mode operation, or a second resonant frequency, greater than the first resonant frequency, responsive to odd mode operation. The VCO may include a first electrically tunable varactor shunted across the first capacitance circuit and a second electrically tunable varactor shunted across the second capacitance circuit.

An electronic device may include a harmonic rejection mixer with a delay line, mixer array, and load. The delay line may generate LO phases. Each mixer in the array may have a first input that receives an LO phase and a second input coupled to an input switch and the first input of the next mixer circuit through an inter-mixer switch. The load may include a set of switches. In a transmit mode, the input switches and set of switches may be closed while the inter-mixer switches are open. In a self-calibration mode, the input switches and set of switches may be open while the inter-mixer switches are closed. A controller may sweep through phase codes for the programmable delay line while storing a digital output from the load. The controller may calibrate the phase code based on the digital output.

Systems and methods for forming a mm wave resonant filter include a lithographically fabricated high Q resonant structure. The resonant structure may include a plurality of cavities, each cavity having a characteristic frequency that defines its passband. A filter may include a plurality of resonant structures, and each resonant structure may include a plurality of cavities. These cavities and filters may be fabricated lithographically.

A small-size high-power terahertz oscillator achieves a stable oscillation in a terahertz frequency band even at room temperature. The high-power terahertz oscillator has a structure in which a bow-tie antenna is disposed on a substrate, a cavity resonator, which includes two cavities, is disposed at a power supply portion of the bow-tie antenna, and a resonant tunneling diode (RTD) is disposed along a bottom of a wall of the cavity resonator, which defines the two cavities, and stably oscillates waves in the terahertz frequency band at room temperature by using the RTD, the bow-tie antenna and the cavity resonator.

An electronic device may include a harmonic rejection mixer with a delay line, mixer array, and load. The delay line may generate LO phases. Each mixer in the array may have a first input that receives an LO phase and a second input coupled to an input switch and the first input of the next mixer circuit through an inter-mixer switch. The load may include a set of switches. In a transmit mode, the input switches and set of switches may be closed while the inter-mixer switches are open. In a self-calibration mode, the input switches and set of switches may be open while the inter-mixer switches are closed. A controller may sweep through phase codes for the programmable delay line while storing a digital output from the load. The controller may calibrate the phase code based on the digital output.

An electronic device may include a harmonic rejection mixer with a delay line, mixer array, and load. The delay line may generate LO phases. Each mixer in the array may have a first input that receives an LO phase and a second input coupled to an input switch and the first input of the next mixer circuit through an inter-mixer switch. The load may include a set of switches. In a transmit mode, the input switches and set of switches may be closed while the inter-mixer switches are open. In a self-calibration mode, the input switches and set of switches may be open while the inter-mixer switches are closed. A controller may sweep through phase codes for the programmable delay line while storing a digital output from the load. The controller may calibrate the phase code based on the digital output.

[Problem]

An object of the present invention is to provide a small-size high-power terahertz oscillator that achieves a stable oscillation in a terahertz frequency band even at a room temperature.

[Means for solving the problem]

The present invention is the high-power terahertz oscillator that has a structure in which a bow-tie antenna is disposed on a substrate, a cavity resonator which includes two cavities is disposed at a power supply portion of the bow-tie antenna and a RTD is disposed along a bottom of a wall of the cavity resonator which defines the two cavities, and stably oscillates waves in the terahertz frequency band at room temperature by using the RTD, the bow-tie antenna and the cavity resonator.

A voltage controlled oscillator (VCO) circuit employing digital amplitude control of the output oscillating signal and method of operation. The digital control is provided by an analog to digital converter (ADC) element that is shared among many other operating blocks in a system. In a configuration, the oscillator current is obtained by implementing transistors in a linear region and controlling them digitally. The optimum amplitude detection is performed by measuring the DC voltage at the common mode nodes in the oscillator, and is realized using reduced time compared to an extensive frequency measurement over a long time window. The digital control is implemented using an on-chip regulator, and employs digital controls for adjusting the current consumption which leads to low on-chip area overhead, low cost, and a scalable implementation. In an implementation, a one-time code can be obtained for optimum phase noise operation when providing the digital amplitude control.

A high frequency push-push oscillator is disclosed. The high frequency push-push oscillator includes a resonant circuit, including tank transmission lines or an inductor capacitor (LC) tank circuit, for generating a differential signal having a resonant frequency, and a Gm-core circuit for converting the differential signal to an output signal having an output frequency that is higher than the resonant frequency. The Gm-core circuit includes cross-coupled first and second transistors having first and second gates, drains, and sources, respectively, and first and second gate transmission lines. The first and second drains are in electrical communication with the resonant circuit. The first gate transmission line is joined with the first gate and the resonant circuit and the second gate transmission line is joined with the second gate and the resonant circuit. The Gm-core circuit includes a differential transmission line positioned between the first and second gates of the first and second transistors.

The present disclosure relates to an oscillator device (15) comprising an amplifier unit (16) and a tunable waveguide resonator (1) which in turn comprises a rectangular waveguide part (2) having electrically conducting inner walls (3) and a first waveguide port (4). The amplifier unit (16) is arranged to be electrically connected to the waveguide resonator (1) via the first waveguide port (4) by means of a first connector (17). The waveguide resonator (1) comprises at least one tuning element (6) positioned within the waveguide part (2), wherein each tuning element (6) comprises an electrically conducting body (7) and a holding rod (8a, 8b). The holding rod (8a, 8b) is attached to the electrically conducting body (7) and is movable from the outside of the waveguide resonator (1) such that the electrically conducting body (7) can be moved between a plurality of positions within the waveguide part (2) by means of the holding rod (8a, 8b).