Kaikutek Inc.

Mediatek Corporation

National Taiwan University

Pang-Ning Chen

Chen-Lun Lin

Ying-Chia Chen

Wei-Jyun Wang

Yu-Li Hsueh

Mike Chun Hung Wang

Mike Chun-Hung Wang

Chao-Ching Hung

Po-Chun Huang

Jian-Yu Ding

Pi-An Wu

Jr-I Lee

Pen-Jui Peng

A low voltage inverter-based amplifier includes a first inverter-based amplification module, a second inverter-based amplification module, an inverter-based feedforward module, and an inverter-based common mode detector. The first inverter-based amplification module receives an input signal. The second inverter-based amplification module receives the input signal through the inverter-based feedforward module, and receives a first output signal from the first inverter-based amplification module. The inverter-based common mode detector receives an amplified signal from the second inverter-based amplification module, and outputs a feedback signal to the second inverter-based amplification module. Since the first and the second inverter-based amplification modules are both inverter-based, the supply voltage of the low voltage inverter-based amplifier is provided to supply one PMOS and one NMOS for normal operation. Therefore, a number of cascade MOSs of the low voltage inverter-based amplifier is two, and the low voltage inverter-based amplifier can be normally operated under the low supply voltage.

Low voltage inverter-based amplifier

A frequency-modulated continuous-wave radar system includes a waveform generator, a delta-sigma modulation circuit, a voltage controlled oscillator, a frequency divider circuit, a control circuit, an injection locked oscillator, a power amplifier circuit, a first power detection circuit, a second power detection circuit, a third power detection circuit, and a calibration engine circuit. The waveform generator, the delta-sigma modulation circuit, the voltage controlled oscillator, the frequency divider circuit, and the control circuit form a phase locked loop. The calibration engine circuit is coupled to the delta-sigma modulation circuit, the voltage controlled oscillator, the injection locked oscillator, the power amplifier circuit, the first power detection circuit, the second power detection circuit, and the third power detection circuit for adjusting frequency gains of the voltage controlled oscillator, the injection locked oscillator, and the power amplifier circuit to approach wideband flatness frequency responses.

Frequency-modulated continuous-wave radar system and frequency tracking method for calibrating frequency gains of a radio frequency signal to approach wideband flatness frequency responses

An oscillating circuit has an injection-locked oscillator (ILO) and a calibration circuit. The ILO has a Gm cell and an LC tank. A first node of the Gm cell receives a first injection signal, and a second node of the Gm cell receives a second injection signal. The first injection signal and the second injection signal are differential signals. The Gm cell provides a negative resistance between a first output end and a second output end of the Gm cell. When the calibration circuit tunes a resonant frequency of the LC tank of the ILO, the magnitude of the negative resistance is reduced to control the ILO to stop self-oscillating. After finishing tuning the resonant frequency of the LC tank, the calibration circuit controls the ILO to start self-oscillating by increasing the magnitude of the negative resistance.

Oscillating circuit and method for calibrating a resonant frequency of an LC tank of an injection-locked oscillator (ILO) of the oscillating circuit while stopping self-oscillation of the ILO

A method for enhancing linearity of the receiver front-end system includes receiving a radio frequency signal by an antenna, converting the radio frequency signal to first differential signals by a transformer module, adjusting frequencies of the first differential signals to generate second differential signals by a mixer module, detecting a common signal in order to reduce a common error of the second differential signals, and generating third differential signals according to a reference signal after the common error is reduced from the second differential signals. The first differential signals, the second differential signals, and the third differential signals are unbalanced.

Method for enhancing linearity of a receiver front-end system by using a common-mode feedback process and receiver front-end system thereof

A divider-less phase locked loop (PLL) includes a phase frequency detector (PFD), a charge pump (CP), a voltage controlled oscillator (VCO), a delay unit, and a clock gating unit. The PFD is electrically connected to the VCO through the CP, and the CP outputs a voltage control signal to the VCO. The VCO generates an output signal. The delay unit receives and delays a reference signal to generate a delay signal. The clock gating unit samples the output signal according to the delay signal. Since the clock gating unit samples the output signal according to the delay signal, the divider-less PLL does not need to include a divider to divide a frequency of the output signal. Therefore, power consumption of the divider-less PLL can be reduced.

Divider-less phase locked loop

A quadrature clock generating apparatus connected to a local oscillator generating an input clock signal and an inverted input clock signal includes a fractional dividing circuit and a quadrature signal generating circuit. The fractional dividing circuit is configured for receiving the input clock signal and the inverted input clock signal, and for performing frequency-division upon the input clock signal and the inverted input clock signal to generate a frequency-divided clock signal according to a fractional dividing parameter. The quadrature signal generating circuit is configured for receiving the input clock signal, the inverted input clock signal, and the frequency-divided clock signal to generate a plurality of quadrature clock signals.

Quadrature clock generating mechanism of communication system transmitter

A signal generator generates an output signal according to an oscillating signal. The signal generator has a plurality of edge sampling circuits and an edge combining circuit. Each of the edge sampling circuits receives the oscillating signal, samples the oscillating signal to obtain at least one of a rising edge and a falling edge in one cycle of the oscillating signal, and outputs a sampled signal using the at least one of the rising edge and the falling edge. The edge combining circuit combines a plurality of sampled signals generated by the edge sampling circuits, respectively, to generate the output signal.

Signal generator using multi-sampling and edge combining and associated signal generating method

A phase detector including a first latch and a control circuit is provided. The first latch generates a first output signal and a second output signal in response to a phase difference between a first input signal and a second input signal. Each of the first and second output signals includes first phase information and second phase information of the phase difference. The control circuit generates a phase indicating signal in response to the first phase information of the phase difference. The phase indicating signal indicates a relative position between the first input signal and the second input signal.

Phase detector

A fractional dividing module includes an output clock generating circuit, for receiving an input clock signal and generating an output clock signal according to a first control signal, comprising a first delay unit, for delaying the input clock signal to generate a delayed input clock signal; and a selecting unit, for selecting one of the input clock signal and the delayed input clock signal to generate the output clock signal according to the first control signal; and a control circuit, for dividing the output clock signal to generate the first control signal according to a dividing control signal, wherein the dividing control is adjusted to control a frequency ratio between the output clock signal and the input clock signal.

Fractional dividing module and related calibration method

A radio frequency transmitting device includes a frequency multiplier circuit, a mixer circuit, a power splitter, a plurality of phase shifting circuits, a plurality of amplifiers, and a plurality of antennas. The frequency multiplier circuit is configured to amplify a fundamental signal to generate a harmonic signal. The mixer circuit is configured to generate a RF signal based on an input signal and the harmonic signal. The power splitter is configured to generate a plurality of sub-RF signals. The phase shifting circuits are configured to shift the phase of the sub-RF signals. The amplifiers are configured to amplify the power of the sub-RF signals. The antennas are configured to transmit the sub-RF signals. Furthermore, a radio frequency receiving device is also disclosed herein.

Growing community of inventors

Taipei, Taiwan

Pang-Ning Chen