A delta-sigma modulator may comprise a loop filter for integrating and outputting a difference between an input signal and an analog signal; a quantizer for quantizing and outputting a signal output from the loop filter; and a digital-to-analog converter (DAC) for outputting the analog signal by digital-to-analog converting a signal output from the quantizer. Also, the loop filter may comprise an operational amplifier; and a circuit including at least one capacitor, at least one resistor, and at least one switch which are connected to the operational amplifier. Also, signal transfer characteristics of the loop filter satisfy a third-order transfer function or a second-order transfer function by turning on or off the at least one switch.

A delta-sigma modulator may comprise a loop filter for integrating and outputting a difference between an input signal and an analog signal; a quantizer for quantizing and outputting a signal output from the loop filter; and a digital-to-analog converter (DAC) for outputting the analog signal by digital-to-analog converting a signal output from the quantizer. Also, the loop filter may comprise an operational amplifier; and a circuit including at least one capacitor, at least one resistor, and at least one switch which are connected to the operational amplifier. Also, signal transfer characteristics of the loop filter satisfy a third-order transfer function or a second-order transfer function by turning on or off the at least one switch.

Provided is a wireless communication receiver including an antenna for receiving an RF signal; a first mixer, coupled to the antenna, for performing frequency conversion on the RF signal from the antenna by mixing the RF signal with a local oscillator signal to provide a first intermediate frequency (IF) signal; and a first filter, coupled to the first mixer, configured to pass a predetermined band of frequencies of the first IF signal and to generate a first channel signal. The first filter includes a negative feedback loop coupled to the first mixer for performing negative feedback loop control on the first IF signal; and a positive capacitive feedback loop coupled to the first mixer for performing positive capacitive feedback loop control on the first IF signal, the negative feedback loop and the positive capacitive feedback loop being coupled in parallel.

We disclose transconductor-capacitor classical dynamical systems that emulate quantum dynamical systems and quantum-inspired systems by composing them with 1) a real capacitor, whose value exactly emulates the value of the quantum constant h termed a Planck capacitor; 2) a quantum admittance element, which has no classical equivalent, but which can be emulated by approximately 18 transistors of a coupled transconductor system; 3) an emulated quantum transadmittance element that can couple emulated quantum admittances to each other; and 4) an emulated quantum transadmittance mixer element that can couple quantum admittances to each other under the control of an input. These four parts can be composed together to create arbitrary discrete-state, traveling-wave, spectral, or other quantum systems.

We disclose transconductor-capacitor classical dynamical systems that emulate quantum dynamical systems and quantum-inspired systems by composing them with 1) a real capacitor, whose value exactly emulates the value of the quantum constant h termed a Planck capacitor; 2) a quantum admittance element, which has no classical equivalent, but which can be emulated by approximately 18 transistors of a coupled transconductor system; 3) an emulated quantum transadmittance element that can couple emulated quantum admittances to each other; and 4) an emulated quantum transadmittance mixer element that can couple quantum admittances to each other under the control of an input. We describe how these parts may be composed together to emulate arbitrary two-state and discrete-state quantum or quantum-inspired systems including stochastics, state preparation, probability computations, state amplification, state attenuation, control, dynamics, and loss compensation.

We disclose transconductor-capacitor classical dynamical systems that emulate quantum dynamical systems and quantum-inspired systems by composing them with 1) capacitors that represent termed Planck capacitors; 2) a quantum admittance element, which can be emulated efficiently via coupled transconductors; 3) an emulated quantum transadmittance element that can couple emulated quantum admittances to each other; and 4) an emulated quantum transadmittance mixer element that can couple emulated quantum admittances to each other under the control of an input. We describe a Quantum Cochlea, a biologically-inspired quantum traveling-wave system with coupled emulated quantum two-state systems for efficient spectrum analysis that uses all of these parts. We show how emulated quantum transdmittance mixers can help represent an exponential number of quantum superposition states in the spectral domain with linear classical resources, even if they are not all simultaneously accessible as in actual quantum systems.

Two types of high-pass filter circuit and a band-pass filter circuit are provided. Both types of high-pass filter circuit include a capacitor configured to input an input signal, a resistor connected between an output terminal of the capacitor and a prescribed bias voltage, and a signal output circuit connected to the output terminal of the capacitor and configured to buffer-amplify the input signal for output. In one of the two types of high-pass filter circuits, the resistor is formed on an SOI semiconductor substrate and includes two PN junction diodes that are inversely connected to each other in parallel. In the other one of the high-pass filter circuits, the resistor is formed on an SOI semiconductor substrate and includes two MOS transistors that are inversely connected to each other in parallel.

Techniques to maintain gain flatness in the frequency response of a passband signal over a circuit chain. The techniques may be employed in the receive chain of a millimeter wave band wireless receiver, in the transmit chain of a millimeter wave band wireless transmitter, or in both the receive chain and the transmit chain of a millimeter wave band wireless transceiver. The techniques include mismatching the input and output impedance of a passive low pass filter used in the chain to peak the gain of the passband signal at or near the cutoff frequency (Fc) of the filter.

A third-order loop filter for a delta signal modulator comprises a single operational amplifier, and a resistor-capacitor network including a plurality of capacitors and a plurality of resistors which are connected to the operational amplifier, and satisfy a third-order transfer function.

A third-order loop filter for a delta signal modulator comprises a single operational amplifier, and a resistor-capacitor network including a plurality of capacitors and a plurality of resistors which are connected to the operational amplifier, and satisfy a third-order transfer function.