Patent application number | Description | Published |
20080261543 | TRANSMISSION CIRCUIT AND COMMUNICATION DEVICE - Provided is a transmission circuit capable of operating with high linearity and with low noise. An AM variable fc filter | 10-23-2008 |
20090060089 | POLAR MODULATION TRANSMITTER CIRCUIT AND COMMUNICATIONS DEVICE - Provided is a transmitter circuit capable of operating with low distortion and high efficiency even in a modulation method using wide modulation bandwidth. In the transmitter circuit, a signal generation section ( | 03-05-2009 |
20090079511 | Polar Modulation Transmission Circuit and Communication Device - A transmission circuit for outputting transmission signals with a low distortion and a high efficiency over a wide range of output power is provided. A signal generation section ( | 03-26-2009 |
20090156142 | TRANSMITTER AND COMMUNICATION APPARATUS - A signal generation section | 06-18-2009 |
20100027445 | TRANSMISSION CIRCUIT, METHOD FOR DETERMINING DELAY TIME USED IN THE TRANSMISSION CIRCUIT, AND COMMUNICATION APPARATUS USING THE TRANSMISSION CIRCUIT - Provided are generating an amplitude signal and a frequency signal through signal processing of data, angle-modulating the frequency signal, adjusting a delay time of the amplitude signal, amplitude amplifying of outputting a signal based on a magnitude of the amplitude signal having the delay time adjusted, amplitude-modulating a signal outputted through the angle modulating, by the signal outputted through the amplitude amplifying, so as to output an obtained signal as a modulated signal, and delay processing of calculating a delay time difference between the amplitude signal and the frequency signal, based on the modulated signal, and performing feedback control for the delay time until the delay time difference is eliminated, only in a test period. Through the signal generating, a sinusoidal signal is outputted as each of the amplitude signal and the frequency signal during the test period. | 02-04-2010 |
20100203852 | FREQUENCY MODULATION CIRCUIT, TRANSMITTER, AND COMMUNICATION APPARATUS - A bandpass type delta sigma modulation section | 08-12-2010 |
20110012688 | FREQUENCY MODULATOR AND METHOD FOR ADJUSTING GAIN THEREOF - A frequency modulator capable of performing frequency modulation without increasing quantization noise; and a method for adjusting the gain thereof are provided. An input signal is gain-adjusted by a gain adjustment section and outputted to a frequency modulation section. The frequency modulation section is gain-controlled based on a first signal. For setting a digital gain coefficient and an analog gain coefficient of the gain adjustment section, a test signal is inputted. In this state, in a generation section, first control information for setting the digital gain coefficient and second control information for setting the analog gain coefficient are generated based on information regarding a state of the frequency modulation section. | 01-20-2011 |
20110018640 | TRANSMITTER UTILIZING A DUTY CYCLE ENVELOPE REDUCTION AND RESTORATION MODULATOR - A broad power band transmitter utilizing a duty cycle modulator achieves 80dB of power range for 3G signals. The present invention greatly improves the efficiency of transmitters used in mobile phones, for example, by using the duty cycle modulator during medium and low power levels of the transmitting power amplifier. The power amplifier operates in three different modes based upon the amplifier power level selected. The power amplifier operates in an EER mode during high power levels, in a DCM ERR mode during medium power levels, and in a DCM mode during low power levels. | 01-27-2011 |
20110058622 | METHOD AND APPARATUS FOR PROVIDING HIGH EFFICIENCY CARTESIAN MODULATION - The disclosure relates to a method and apparatus for providing efficient signal transmission. Conventional linear amplifiers are most efficient when operated in compressed mode. In the compressed mode, the digital power amplifier switches between the on and off modes. A digital power amplifier operates in compressed mode only if the incoming signal is an on-off constant envelop signal. In one embodiment, the disclosure provides a method and apparatus for converting a digital baseband signal to on-off constant envelop signals for processing through binary-weighted or thermometer-weighted amplifier which are operated in compressed mode. | 03-10-2011 |
20110098006 | TRANSMITTER CIRCUIT AND COMMUNICATION DEVICE USING THE SAME - A transmitter circuit of the present invention includes: a signal generator | 04-28-2011 |
20110176636 | HIGH-EFFICIENCY ALL-DIGITAL TRANSMITTER - A low cost high-efficiency all-digital transmitter using all-digital power amplifiers (“DPA”) and various mapping techniques to generate an output signal, which substantially reproduces a baseband signal at a carrier frequency. A baseband signal generator generates a baseband signal which is quantized by a signal processor using a quantization map. A DPA control mapper outputs control signals to phase selectors using the quantized signal and a quantization table. Each phase selector receives one of the control signals and outputs a waveform at a carrier frequency with a phase corresponding to the control signals, or an inactive signal. Each DPA in a DPA array has an assigned weight, receives one of the waveforms from the phase selectors, and outputs a power signal according to the weight of the DPA and the phase of the received waveform. The combined power signal substantially reproduces the baseband signal at the carrier frequency. | 07-21-2011 |
20110305171 | TRANSMISSION CIRCUIT AND TRANSMISSION METHOD - A transmission circuit that performs modulation based on a phase difference signal and an amplitude signal includes an asymmetrical phase rotation device. The asymmetrical phase rotation device performs an operation of subtracting 2π from a value of the phase difference signal when the value of the phase difference signal is greater than a predetermined positive threshold value, or an operation of adding 2π to the value of the phase difference signal when the value of the phase difference signal is less than a predetermined negative threshold value. Accordingly, the transmission circuit has distortion reduction characteristics improved uniformly over a range of frequencies higher or lower than a carrier wave band. | 12-15-2011 |
20110305292 | NONLINEAR FILTER AND TRANSMISSION CIRCUIT - A nonlinear filter includes: a determination unit that determines, based on I and Q signals inputted into the determination unit, whether or not to perform pulse insertion; a rotation detector that detects a rotation direction of the I and Q signals on an IQ plane with respect to the origin of the IQ plane; a pulse generator that generates, when the determination unit determines to perform the pulse insertion, a pulse of which at least one of the direction and the magnitude is determined in accordance with at least the detected rotation direction; and an adder that inserts the pulse into the I and Q signals and outputs resultant I and Q signals. | 12-15-2011 |