A voltage-controlled oscillator device includes first and second voltage-controlled oscillators, a first switch group including two first switches, and a second switch group including two second switches. The first voltage-controlled oscillator includes a first inductor group, a first negative resistance circuit and a first voltage output terminal group. The second voltage-controlled oscillator includes a second inductor group, a second negative resistance circuit and a second voltage output terminal group. For the first switch group, first control terminals are electrically connected to the first voltage output terminal group, first input terminals are electrically connected to the second voltage output terminal group, first output terminals are electrically connected. For the second switch group, second control terminals are electrically connected to the second voltage output terminal group, second input terminals are electrically connected to the first voltage output terminal group, second output terminals are electrically connected.

Systems, methods, and circuits are provided for facilitating negative resistance margin testing in an oscillator circuit. An example oscillator circuit includes amplifier circuitry configured to be coupled in parallel with a resonator and variable resistance circuitry configured to, in response to a resistance control signal, adjust a resistance of the oscillator circuit.

An electromagnetic wave transmission apparatus of the present invention includes a transmission unit whose voltage-current characteristics have a local maximum value and a local minimum value located on a higher voltage side than the local maximum value and which transmits an electromagnetic wave indicating a modulation signal, an acquisition unit which acquires a digital signal, and a modulation unit which modulates the digital signal into the modulation signal which is a signal using voltage values of three levels or more in an oscillation region which is a voltage region that is equal to or more than a voltage of the local maximum voltage and equal to or less than a voltage of the local minimum voltage. The transmission unit preferably transmits a synchronization signal as at least a part of the modulation signal. In this case, the synchronization signal preferably includes a maximum value and a minimum value among the voltage values of three levels or more, and includes a pattern in which the voltage value transitions from one of the maximum value and the minimum value to the other.

An electromagnetic wave transmission apparatus of the present invention includes a transmission unit whose voltage-current characteristics have a local maximum value and a local minimum value located on a higher voltage side than the local maximum value and which transmits an electromagnetic wave indicating a modulation signal, an acquisition unit which acquires a digital signal, and a modulation unit which modulates the digital signal into the modulation signal which is a signal using voltage values of three levels or more in an oscillation region which is a voltage region that is equal to or more than a voltage of the local maximum voltage and equal to or less than a voltage of the local minimum voltage. The transmission unit preferably transmits a synchronization signal as at least a part of the modulation signal. In this case, the synchronization signal preferably includes a maximum value and a minimum value among the voltage values of three levels or more, and includes a pattern in which the voltage value transitions from one of the maximum value and the minimum value to the other.

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.

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.

One aspect of the present disclosure provides a terahertz-wave detector including a semiconductor substrate, an active element formed on the semiconductor substrate and a first resistive portion electrically connected in parallel with the active element.

One aspect of the present disclosure provides a terahertz-wave detector including a semiconductor substrate, an active element formed on the semiconductor substrate and a first resistive portion electrically connected in parallel with the active element.

An integrated circuit includes a semiconductor substrate and a plurality of circuit elements in or on the substrate. The circuit elements are defined by standard layout cells selected from a cell library. The circuit elements including a plurality of flip-flops. Each flip-flop has a data input terminal, a data output terminal, a clock input terminal, and a clock output terminal. A first one of the flip-flops directly abuts a second flip-flop such that the clock output terminal of the first flip-flop electrically connects with the clock input terminal of the second flip-flop.

An electromagnetic wave transmission apparatus of the present invention includes a transmission unit whose voltage-current characteristics have a local maximum value and a local minimum value located on a higher voltage side than the local maximum value and which transmits an electromagnetic wave indicating a modulation signal, an acquisition unit which acquires a digital signal, and a modulation unit which modulates the digital signal into the modulation signal which is a signal using voltage values of three levels or more in an oscillation region which is a voltage region that is equal to or more than a voltage of the local maximum voltage and equal to or less than a voltage of the local minimum voltage. The transmission unit preferably transmits a synchronization signal as at least a part of the modulation signal. In this case, the synchronization signal preferably includes a maximum value and a minimum value among the voltage values of three levels or more, and includes a pattern in which the voltage value transitions from one of the maximum value and the minimum value to the other.