Abstract: A dual-mode mobile terminal, which can access synchronous and asynchronous mobile communication systems, includes a key input panel and a controller. The key input panel includes a call switching key for switching between calls from the two systems and a call end key for ending calls from the two systems. While the terminal performs communication of one call received from one of the two systems in a general communication mode over a communication channel currently established by the one system, the controller determines whether an incoming call is received from the other system. If the incoming call is received, the controller notifies the user of receipt of the incoming call. If the call switching key is pressed, the controller prepares a communication environment for communication of the incoming call, allowing the user to perform the communication of the incoming call while maintaining the currently established communication channel.

Abstract: A device and a method for automatically adjusting the time of an analog watch in an analog watch-mounted terminal are disclosed. The method comprises the steps of: sensing by a sensor a predetermined time for adjusting the time of the analog watch; determining if a predetermined time-adjusting cycle has occurred when the interrupt signal is input from the sensor; and comparing the system time with the present analog time, in the case of a time-adjusting cycle, and transmitting a drive signal to an analog watch drive unit for the purpose of driving the hour hand and the minute hand according to the difference between the times.

Abstract: A dual-mode mobile terminal that connects to synchronous and asynchronous mobile communication systems and a method for displaying accurate time information in the terminal. The terminal includes a timer and a controller. The timer generates an interrupt signal at a predetermined time. When entering an asynchronous communication mode, the controller starts the timer to generate the interrupt signal at the predetermined time. When receiving the interrupt signal from the timer, the controller connects to the synchronous mobile communication system to obtain accurate time information therefrom and then connects to the asynchronous mobile communication system to switch to the asynchronous communication mode.

Abstract: A dual-mode mobile terminal capable of accessing two or more different mobile communication systems in which the terminal includes a controller for determining if the terminal is currently located in service areas of the mobile communication systems, and displaying an indicator of at least on of mobile communication systems, which currently provides a communication service to the terminal.

Abstract: There is provided an apparatus for adjusting the time of analog watch in a terminal having the analog watch, which comprises an analog watch unit and a control unit. The analog watch unit includes an oscillation circuit for generating a standard signal with a predetermined frequency; a division circuit for dividing the standard signal by a predetermined division ratio according to a control signal and generating a divided signal; a driving circuit for generating a driving signal according to the divided signal; and a step motor driven by the driving signal, for moving the elements of the analog watch. The control unit provides the control signal to the division circuit of the analog watch when a predetermined time adjustment manipulation is inputted. The hands of the analog watch move faster than a general time indication according to an input state of a time adjustment key.

Abstract: A communication terminal for providing user information of a receiving party and a method thereof.

Abstract: There is provided a control method for driving backlight parts to provide backlight to a display and a keypad in a mobile terminal. The display backlight part and the keypad backlight part are controlled to be selectively driven, according to the state of the cover and the presence or absence of key input data. Therefore, power dissipation caused by unnecessary operation of the backlights can be prevented.

Abstract: A device for controlling a receiving amplifier in a radio terminal by monitoring the transmission/reception mode and varying the current to an amplifier that amplifies an output signal to vary the linearity of the amplifier according to a received signal strength indicator (RSSI) measured of the input signal and a measured input signal quality.

Abstract: The invention relates to an antenna structure for a portable radio telephone comprising a helical antenna and a rod antenna. The helical antenna is inserted into the portable radio telephone, and the rod antenna is concealed when it is retracted into the telephone. The helical antenna is electrically connected to a Radio Frequency (RF) terminal in the telephone and the rod antenna is electrically connected to a ground terminal in a Printed Circuit Board (PCB) of the telephone to have a dipole structure.

Abstract: A device for controlling voltage in a power amplifier of a portable wireless terminal according to the present invention, includes a power amplifier adapted to adjust an amplification degree of a signal inputted in response to a supply state of a reference voltage to output the adjusted signal. The device also includes a comparator/limiter adapted to compare a value of a transmitting automatic gain controlled (TX_AGC) supply voltage and a value of an operating supply voltage to output the compared result and a power supply conversion section adapted to convert a state of the compared result outputted from the comparator/limiter into a reference voltage state for application to the power amplifier as a reference voltage thereof.

Abstract: A power supply apparatus for a mobile communication terminal having voltage regulators, a receiver and baseband signal processor, a transmitter, a power amplifier, and a DC/DC converter for converting a DC voltage from a battery. In a reception mode of the mobile communication terminal, the power supply apparatus regulates the DC voltage converted by the DC/DC converter and supplies the regulated DC voltage to the receiver and baseband signal processor. In a transmission mode, the power supply apparatus converts the DC voltage to a DC voltage corresponding to a transmission AGC (Automatic Gain Control) voltage which is determined based on a transmission power. The converted DC voltage is then supplied to the receiver and baseband signal processor, the transmitter, and the power amplifier via the voltage regulators. The power supply apparatus has a single DC/DC converter and adaptively varies the output voltage of the DC/DC converter according to the transmission power in the transmission mode.

Abstract: A device for linearizing a transmitter in a digital radio communication system. In the device, a predistortion lookup table stores predistortion data determined by measuring in advance distortion characteristics of the transmitter with respect to input baseband data. During transmission, the device synthesizes the input baseband data with the predistortion data to predistort the input data so as to compensate for the distortion characteristics caused by non-linear elements constituting the transmitter.

Abstract: There is provided a control method for driving backlight parts to provide backlight to a display and a keypad in a mobile terminal. The display backlight part and the keypad backlight part are controlled to be selectively driven, according to the state of the cover and the presence or absence of key input data. Therefore, power dissipation caused by unnecessary operation of the backlights can be prevented.

Abstract: A method for controlling power in a wireless telephone set. The method includes the steps of detecting whether or not any interrupting signals have been generated and performing a user mode for supplying power only to sections necessary for operations according to an origin of the interrupting signals, when said interrupting signals are generated.

Abstract: A device for controlling voltage in a power amplifier of a portable wireless terminal according to the present invention, includes a power amplifier adapted to adjust an amplification degree of a signal inputted in response to a supply state of a reference voltage to output the adjusted signal. The device also includes a comparator/limiter adapted to compare a value of a transmitting automatic gain controlled (TX_AGC) supply voltage and a value of an operating supply voltage to output the compared result and a power supply conversion section adapted to convert a state of the compared result outputted from the comparator/limiter into a reference voltage state for application to the power amplifier as a reference voltage thereof.

Abstract: A receiver with suppressed intermodulation distortion for a radio communication terminal. In the receiver, a low noise amplifier for amplifying a received signal, has an operating power being increased in response to a first control signal to reduce an intermodulation distortion signal. An RF bandpass filter bandpass-filters the signals in a reception frequency band out of the signals output from the low noise amplifier. A mixer mixes an output of the RF bandpass filter with a local oscillation signal to generate an intermediate frequency signal by down-converting the output of the RF bandpass filter. An intermediate frequency amplifier for amplifying the intermediate frequency signal output from the mixer, and having an operating power being increased to reduce the intermodulation distortion signal in response to a second control signal. An intermediate frequency bandpass filter bandpass-filters an intermediate frequency signal out of the signals output from the intermediate frequency amplifier.

Abstract: A self-diagnostic method is provided capable of testing condition of various components for a forklift truck selectively, displaying the result test codes collectively on a display after completing the test, and initiating a quick test mode during a run mode by simply manipulating an accelerator pedal and a direction lever of the forklift truck.

Abstract: A voltage controlled oscillator for upconverter/downconverter in a digital radio communication system has an improved phase noise characteristic and includes: a resonance unit wherein a variable capacitance component is parallel-connected to a series resonance circuit, the variable capacitance component having a capacitance inversely proportional to the level of a control voltage in a preset range and the series resonance circuit having a series resonance point corresponding to the level of a mode voltage, and an oscillating unit for oscillating at a frequency corresponding to a parallel resonance point determined by the resonance unit.

Abstract: A digital radio communication system includes a first down converter for converting down a predetermined radio frequency (RF) signal into a first intermediate frequency (IF) signal according to a first local oscillation signal; a second down converter for converting down the first IF signal into a second IF signal according to a second local oscillation signal; a demodulator for demodulating the second IF signal according to a third local oscillation signal and outputting a predetermined base band of a signal; a modulator for modulating the predetermined base band of signal according to the second local oscillation signal and outputting a third IF signal; a up converter for converting the third IF signal to a RF signal according to the first local oscillation signal; a first phase-locked loop (PLL) for controlling the first local oscillation signal in a direction where the sum of the frequency deviation between the first local oscillation signal and a reference frequency signal and the frequency deviation bet

Abstract: A transmission and reception method and apparatus is capable of supplying local oscillation frequencies for upconversion and downconversion, as well as carrier frequencies for modulation and demodulation by utilizing only one local oscillator. The apparatus includes a reference signal generator for generating a reference signal, and a phase locked loop for locking the output of the reference signal generator to a predetermined frequency. A signal generator generates a signal in response to the output provided from the phase locked loop, and provides the signal to phase shifters in modulation and demodulation circuits. A first frequency multiplier multiplies the output of the signal generator, a first band pass filter band pass filters the output of the first frequency multiplier, and a first amplifier amplifies the output of the first band pass filter and provides the amplified result to an upconversion mixer.