Abstract: The present invention discloses a portable terminal that measures a reference tilt and a method of measuring the reference tilt using the same. The portable terminal includes a movement sensor for measuring a tilt of the portable terminal using a gravitational acceleration value, and a controller for dividing a preset time into separate time sections and measuring an acceleration value in each separate time section by using the movement sensor, calculating a standard deviation of the accelerations in each separate time section and determining one time section in which movement is minimal, and calculating a tilt of the portable terminal from an average of the accelerations in the determined one time section or a sum of weight values therein and setting the calculated tilt as the reference tilt of the portable terminal.

Abstract: An open loop resonator filter employed aperture on the ground plane is disclosed. The open loop resonator filter using apertures on the ground plane formed on the dielectric substrate, the open loop resonator filter including: one or more open loop resonators formed on a upper side of the dielectric substrate and implemented by microstrip lines; and one or more apertures formed on a predetermined area of the ground plane. The present invention can control the coupling coefficient of the open loop resonator without degrading the group delay characteristics by forming the aperture on the ground plane. Therefore, by forming the aperture on the ground plane, it is possible to design a filter having a wide bandwidth characteristic.

Abstract: Disclosed are a method for automatically originating an international call and a mobile communication terminal using the same, such that a function of automatically originating an international call according to movement of a mobile communication terminal between countries is provided. The mobile communication terminal includes a country code detecting unit for informing a country code for a corresponding country by detecting movement of a mobile communication terminal between countries. If the country code detecting unit provides an allowable country code according to the position of the mobile communication terminal, a control unit adds an international dialing code to preset information regarding a call terminating side so as to enable call connection.

Abstract: Disclosed is a quadrature demodulator for high-speed wireless communication, which comprises: an A/D converter for converting received signals into digital signals; a signal recovery unit for recovering carriers and symbol timing from the signals converted by the A/D converter; a decision unit for detecting recovered signals output by the signal recovery unit, and performing a decision process on them; an I/Q gain imbalance detector for detecting gain imbalances of the I and Q-phase components from the recovered signals, and outputting an I/Q gain compensation value for compensating for the gain imbalances; and an I/Q gain compensator, provided between the A/D converter and the signal recovery unit, for reflecting the I/Q gain compensation value output by the I/Q gain imbalance detector to the received signals.

Abstract: An error detecting circuit for detecting the location of an error is provided. The error detecting circuit has an error data storing unit and an error data collecting unit. The error data storing unit divides a circuit having areas, and outputs a plurality of error signals in response to a plurality of state error signals, a serial chain signal, a lock-enable signal, and a chip error signal, which are enabled when an error occurs in the corresponding area. The serial chain signal reads the plurality of state error signals if the chip goes out of order when an error occurs in the circuit. The lock-enable signal determines whether or not to preserve the plurality of state error signals. In response to the serial chain signal, the error data storing unit enables a confirmation of at least one state error signals stored in the error data storing unit.

Abstract: Disclosed is a method for detecting and correcting amplitude and phase imbalances between in-phase (I) and quadrature-phase (Q) components in a high-speed wireless communication quadrature demodulator, which comprises: a) comparing an input signal with a signal determined by a quadrant to which the input signal belongs, and detecting imbalances between I and Q components with respect to the input signal; and b) using the imbalances detected in a) to correct the input signal. The present invention prevents distorting of the demodulator's performance caused by the imbalances to between I and Q components and increases application to high-speed wireless communication.

Abstract: The present invention provides an apparatus for compensating a phase difference of a receiver, the apparatus including: an accumulating unit for accumulating a radio frequency (RF) input signal and generating an accumulated RF signal in order to minimize an effect of a background noise of the RF input signal; a early-local oscillating unit for generating a phase-early local oscillated signal based on a local oscillated signal of the receiver; a late-local oscillating unit for generating a phase-late local oscillated signal based on a local oscillated signal of the receiver; a phase early-late compensating unit for compensating a phase early-late based on the accumulated RF input signal and the phase-early and phase-late local oscillated signals; a look-up table data mapping unit for controlling a phase of the local oscillated signal with respect to a phase difference; and a feedback transmitting unit for transmitting a phase compensating data to the local oscillator.

Abstract: An auto focusing method and apparatus for quantifying a focusing average value, comparing the focusing average value with an acceptance level of a preset focusing evaluation value, and iteratively focusing, while widening the depth of focus, when the focusing average value is lower than the acceptance level.

Abstract: An apparatus and a method for detecting imbalances between an I-channel signal and a Q-channel signal in order to suppress a spurious signal in a direct conversion digital quadrature transmission system is disclosed. The apparatus includes: a compensation signal generating unit for generating a first and a second compensation signals based on a digital I-channel and a digital Q-channel signals; a baseband signal generating unit for generating an I-channel and a Q-channel baseband signals by converting a radio frequency signal into a low frequency signal; and a detecting unit for detecting a phase imbalance and an amplitude imbalance between the digital I-channel and the digital Q-channel signals by using a correlation between the first and the second compensation signals with the I-channel and the Q-channel baseband signals.

Abstract: An apparatus and a method for controlling a gain of I-channel signal and compensating Q-channel signal in response to the gain imbalance based on the gain-controlled I-channel signal as a reference channel signal is disclosed. The apparatus includes: an auto gain controller for controlling a gain of a signal selected from the I-channel signal and the Q-channel signal to have a predetermined amplitude, thereby generating a gain-controlled signal; a detector for detecting a gain imbalance between the gain-controlled signal and the remaining channel signal; and a compensator for compensating the gain imbalance of the remaining channel signal based on the detected gain imbalance.

Abstract: A voltage controlled oscillator using a resonator having a photonic bandgap structure and a feedforward circuit is disclosed. The voltage controlled oscillator includes a resonation unit for resonating an oscillated signal by using a resonator having the photonic bandgap structure in order to increase a quality factor and an oscillation unit for controlling a phase of the oscillated signal by using the feedforward circuit in order to reduce phase noise. The present invention can reduce phase noise and increase efficiency of integration by using the photonic bandgap structure of a resonator and the feedforward circuit is used for maintaining high Q factor.

Abstract: A timing loop controller for multilevel modulation scheme is disclosed. The timing loop controller includes a first to fourth computing unit for computing a timing error between an input timing of digital signals and a sampling timing; a first to fourth quantization unit for controlling a direction and an error value of the timing error; a first and second sign detection unit for detecting sign change according to results; a zero crossing detection unit for detecting zero crossing at I axis and Q axis; and a timing error control unit for controlling the timing error value in case there is no sign change. The present invention can increase a zitter performance of timing error according to the signal-to-noise ratio by detecting the timing error, outputting the timing error and controlling the timing error output value only in case there is sign change by additionally equipping the sign variation detector.

Abstract: An open loop resonator filter employed aperture on the ground plane is disclosed. The open loop resonator filter using apertures on the ground plane formed on the dielectric substrate, the open loop resonator filter including: one or more open loop resonators formed on a upper side of the dielectric substrate and implemented by microstrip lines; and one or more apertures formed on a predetermined area of the ground plane. The present invention can control the coupling coefficient of the open loop resonator without degrading the group delay characteristics by forming the aperture on the ground plane. Therefore, by forming the aperture on the ground plane, it is possible to design a filter having a wide bandwidth characteristic.

Abstract: Disclosed is a quadrature demodulator for high-speed wireless communication, which comprises: an A/D converter for converting received signals into digital signals; a signal recovery unit for recovering carriers and symbol timing from the signals converted by the A/D converter; a decision unit for detecting recovered signals output by the signal recovery unit, and performing a decision process on them; an I/Q gain imbalance detector for detecting gain imbalances of the I and Q-phase components from the recovered signals, and outputting an I/Q gain compensation value for compensating for the gain imbalances; and an I/Q gain compensator, provided between the A/D converter and the signal recovery unit, for reflecting the I/Q gain compensation value output by the I/Q gain imbalance detector to the received signals.

Abstract: Disclosed is a method for detecting and correcting amplitude and phase imbalances between in-phase (I) and quadrature-phase (Q) components in a high-speed wireless communication quadrature demodulator, which comprises: s a) comparing an input signal with a signal determined by a quadrant to which the input signal belongs, and detecting imbalances between I and Q components with respect to the input signal; and b) using the imbalances detected in a) to correct the input signal. The present invention prevents distorting of the demodulator's performance caused by the imbalances to between I and Q components and increases application to high-speed wireless communication.

Abstract: The present invention utilizes an even harmonic mixer for canceling a local oscillator (LO) leakage signal. The apparatus for canceling the LO leakage signal includes an in-phase divider, an intermediate frequency (IF) phase divider, an even harmonic mixers, an RF signal phase combiner and a band pass filter (BPF). The in-phase divider divides an LO signal into two in-phase LO signals, wherein the LO signal is inputted from an exterior LO. The IF phase divider divides an IF signal into two out-of-phase IF signals of which a phase difference is 90°, wherein the IF signal is inputted from an exterior means. The even harmonic mixer outputs two out-of phase RF signals of which the phase difference is 90°, after even-harmonic mixing of two in-phase LO signals divided by the in-phase divider and two out-of-phase IF signals divided by the IF phase divider.

Abstract: An error detecting circuit for quickly detecting the location of an error is provided. The error detecting circuit has an error data storing unit and an error data collecting unit. The error data storing unit divides a circuit which is implemented in a chip into predetermined areas and outputs a plurality of error signals in response to a plurality of state error signals, a serial chain signal, a lock-enable signal, and a chip error signal. Each of the plurality of state error signals is enabled when an error occurs in the corresponding predetermined area. The serial chain signal is for reading the plurality of state error signals stored in the chip if the chip goes out of order when an error occurs in the circuit implemented in the chip. The lock-enable signal is for determining whether or not to preserve the plurality of the generated state error signals. The error data collecting unit outputs the chip error signal in response to the plurality of error signals output from the error data storing unit.

Abstract: In one embodiment, the system and device of the present invention extracts unique numerical information from a fingerprint. A fingerprint is first scanned and the scanned image is enhanced. The blurred area of the image is restored and the enhanced image is binarized. The binarized image is then thinned. A core point in the image is detected and minutiae within a given radius from the core point are detected. A number is then extracted from the image by computing relation of minutiae to the core point.