National Science Council

National Taiwan University

Industrial Technology Research Institute

National Science Council of Republic of China

Jing-Shown Wu

Shen-Iuan Liu

Hen-Wai Tsao

Yang-Han Lee

Shyh-Lin Tsao

Yu-Lin Shiao

Poki Chen

Poko Chen

Chui-Fwu Tsai

Ruey-Yuan Tsai

Hen-Wei Tsao

Yi-Sing Hsiao

A transmitter includes an encoding module, an adaptive hierarchical signal mapping module and a transceiver module. The encoding module receives an input signal and encodes the input signal. The input signal includes data to be transmitted. The adaptive hierarchical signal mapping module modulates the encoded signal according to one or more hierarchical level distance ratios to obtain modulated symbols. The hierarchical level distance ratio defines distances between the modulated symbols. The transceiver module generates a radio frequency signal according to the modulated symbols and transmits the radio frequency signal to an air interface.

Methods for carrier frequency offset detection and compensation and transmitters and receivers utilizing the same

A receiver used for an orthogonal frequency-division multiplexing (OFDM) system is provided. A signal processing device receives an OFDM symbol and processes the OFDM symbol according to the OFDM symbol and a carrier frequency offset compensation coefficient to generate a processed signal. The OFDM symbol includes pilots which have been hierarchically modulated and the processed signal includes the processed pilots. A signal analysis device collects the processed pilots of the processed signal and detects carrier frequency offset to generate the carrier frequency offset compensation coefficient to the signal processing device according to the processed pilots and a plurality of target decision bit error rates. A channel detection module detects a channel response of the processed signal according to the processed pilots and compensates the processed signal to generate an output data.

Methods and receivers of carrier frequency offset detection

A transceiver used for an orthogonal frequency-division multiplexing (OFDM) system is provided, including: a signal processing device for receiving an OFDM symbol and processing the OFDM symbol to generate a processing signal according to the OFDM symbol, wherein the OFDM symbol having pilots which have been hierarchically modulated; a pilot signal analysis device for collecting the processing pilots of the processing signal and demodulating the processing pilots to generate a plurality of levels where one of the plurality of levels comprises a plurality of refinement bits; a degree difference analysis module for generating a plurality of degree differences according to the refinement bits and detecting channel classification according to the degree differences to transmit a channel classification signal; and a channel detection module for generating and transmitting a best modulation indication signal to another transceiver to adjust modulation scheme according to the channel classification signal.

Methods and transceivers for channel classification

A CMOS pulse shrinking delay element with deep subnanosecond resolution applicable to a Time-to-Digital Converter (TDC) can control its pulse shrinking or expanding capability be adjusting the dimension ratio between internal adjacent elements. This eliminates the need in prior CMOS pulse shrinking delay elements to adjust an external bias voltage or continuously calibrate the element in order to control pulse shrinking or expanding capabilities, facilitates simplification of circuits using the delay element, permits more precise design and control of the pulse shrinking or expanding capabilities of every element in a TDC circuit, and in practice reduces single shot errors in a cyclic TDC utilizing the pulse shrinking delay element to on the order of ten picoseconds, resulting in a TDC having extremely fine resolution, excellent accuracy, low power consumption, and low sensitivity to supply voltage and ambient temperature variations.

CMOS pulse shrinking delay element with deep subnanosecond resolution

This invention proposed a temperature and optical frequency sensor using two different optical resonators. The fiber with different thermal expansion factor and refractive index can be used to sense the temperature variation. The optical resonators with different cavity lengths can be used to detect the frequency deviation. Applying a laser, a microprocessor and two optical resonators with different thermal expansion factors and resonate lengths, we invent the device which can detect the temperature and frequency simultaneously. Furthermore, the device can provide tunable and highly stabilized light source for optical system application.

Optical frequency and temperature sensor system

Disclosed is a bandpass filter with an input terminal including a sampling circuit for double sampling an input signal from said input terminal, an amplifier, and a conductive connection circuit whose input terminal is coupled to an output of said amplifier, for successively forming three different stages of conductive connection during a time period to form a filtering device with said amplifier. A double sampling bandpass delta-sigma modulator with an input terminal includes two said bandpass filters, a comparator circuit, a multiprocessor, and a feedback circuit which can reduce by half both the required number of amplifiers and the mismatch problems between capacitors and higher frequency operation, and can be easily achieved without additional analog circuits.

Double-sampling pseudo-3-path bandpass sigma-delta modulator

An apparatus is provided for processing a pulse signal. The apparatus includes (1) a pulse-shrinking circuit for shrinking a specific quantity of a pulse width of the pulse signal; and (2) a feedback circuit electrically connected to the pulse-shrinking circuit for repetitively feeding the output pulse signal back to the input end of the pulse-shrinking circuit, the shrunk output pulse signal being further shrunk by the pulse-shrinking circuit in order to obtain a feedback number of the pulse signal before the pulse signal is vanished.

Apparatus for obtaining a pulse width of an unknown pulse signal

A new highly accurate temperature sensor for biomedical applications is proposed in this invention. This sensor including two fiber Bragg gratings with different thermal coefficients can accurately measure temperature with little laser frequency stabilization. This invention improves the measurement resolution and accuracy. Such a sensor can be used to calibrate the other fiber biomedical sensors when those fiber sensors are packaged together.

Highly accurate temperature sensor using two fiber Bragg gratings

A CMOS second generation current conveyor (CCII) and its integrators suitable for MOS technology integrated circuit (IC) applications. Ladder filters based on CCII are realized. CMOS CCII-based circuits can be directly employed in single CCII biquad filters. Four configurations are proposed to synthesize various types of second-order transfer functions.

CMOS current convevor and its filter applications

Switched current differentiators are used as the basic building blocks for discrete time signal processing to implement filters, biquads and high order ladder networks. These circuits can readily be implemented with MOS technology.

Growing community of inventors

Taipei, Taiwan

Jing-Shown Wu