Patent application number | Description | Published |
20080224776 | COMMON-MODE VOLTAGE CONTROLLER - A common-mode voltage controller for adjusting common-mode voltages between a first buffer and a second buffer at a subsequent stage or a preceding stage of the first buffer in a signal transmission circuit, comprising: a first reference voltage generation unit for generating a common-mode voltage corresponding to the first buffer; a second reference voltage generation unit for generating a common-mode voltage corresponding to the second buffer at the subsequent stage or the preceding stage; and a control signal generation unit for generating a control signal for controlling a common-mode voltage of the first buffer according to a difference voltage between an output of the first reference voltage generation unit and an output of the second reference voltage generation unit, and giving the control signal to the first buffer and first reference voltage generation unit. | 09-18-2008 |
20100127744 | DUTY CORRECTION CIRCUIT, DUTY CORRECTION SYSTEM, AND DUTY CORRECTION METHOD - A duty correction circuit is provided which includes a level shifter receives complementary differential input signals having a duty ratio and controls levels of the differential input signals; a TrTf control circuit receives output signals of the level shifter and controls edge angles of the output signals; a waveform shaping circuit receives output signals of the TrTf control circuit and shapes waveforms of the output signals; a first common mode comparator extracts common modes of the output signals of the TrTf control circuit and compares the common modes; and a second common mode comparator extracts common modes of output signals of the waveform shaping circuit and compares the common modes. The level shifter controls the levels based on outputs of the first common mode comparator and the TrTf control circuit controls the edge angles based on outputs of the second common mode comparator. | 05-27-2010 |
20110221524 | RADIO APPARATUS, DISTORTION CORRECTION DEVICE, AND DISTORTION CORRECTION METHOD - When a distortion correction coefficient, which is calculated according to a signal input to a power amplifier and a signal output from the power amplifier, is larger than a first threshold, a distortion correction coefficient corresponding to the input signal is updated to the first threshold. When the calculated distortion correction coefficient is equal to or smaller than the first threshold, the distortion correction coefficient corresponding to the input signal is updated to the calculated distortion correction coefficient. | 09-15-2011 |
20110221525 | RADIO APPARATUS, DISTORTION CORRECTION DEVICE, AND DISTORTION CORRECTION METHOD - An error between the power of an input signal, which is input to a power amplifier, and the power of an output signal, which is output from the power amplifier, is calculated. The calculated error is normalized according to the power of the input signal or the power of the output signal. A distortion correction coefficient, which is stored in a predetermined storage unit in association with the power of the input signal, is updated using the normalized error. | 09-15-2011 |
20110227643 | DISTORTION COMPENSATING APPARATUS, AMPLIFYING APPARATUS, TRANSMITTING APPARATUS, AND DISTORTION COMPENSATING METHOD - A distortion compensating apparatus that compensates signal distortion caused by an amplifier includes a distortion compensating process unit that using a distortion compensation coefficient, compensates distortion of an input signal; a memory unit storing therein the distortion compensation coefficient; and an address generating unit that generates a first address that is based on electrical power of the input signal and is for acquiring the distortion compensation coefficient from the memory unit, and a second address that is based on any one among the electrical power, phase of the input signal and amplitude of the input signal, is for acquiring the distortion compensation coefficient from the memory unit, and is normalized in a normalizing range determined according to the electrical power of the input signal. The distortion compensating process unit acquires the distortion compensation coefficient from the memory unit, based on the first and the second addresses to compensate the distortion. | 09-22-2011 |
20110227644 | DISTORTION COMPENSATING APPARATUS, AMPLIFYING APPARATUS, TRANSMITTING APPARATUS, AND DISTORTION COMPENSATING METHOD - A distortion compensating apparatus that compensates signal distortion caused by an amplifier includes a distortion compensating process unit that using a distortion compensation coefficient, compensates distortion of an input signal; a memory unit that stores the distortion compensation coefficient; and an address generating unit that generates a first address that is based on electrical power of the input signal and for acquiring the distortion compensation coefficient from the memory unit and that generates a second address that is based on a phase of the input signal and for acquiring the distortion compensation coefficient from the memory unit. The distortion compensating process unit acquires the distortion compensation coefficient from the memory unit based on the first and the second addresses to compensate the distortion. | 09-22-2011 |
20110304362 | CURRENT-SOURCE CIRCUIT - A current-source circuit includes a plurality of input-side transistors; a plurality of output-side transistors current-mirror-coupled to the plurality of input-side transistors; an output terminal from which an output current is output; and a switching control circuit to switch the plurality of input-side transistors and activate at least one of the plurality of input-side transistors sequentially. | 12-15-2011 |
20120039415 | DISTORTION COMPENSATION AMPLIFIER DEVICE AND DISTORTION COMPENSATION METHOD - A distortion compensation amplifier device for compensating for distortion of a transmission signal generated by amplifying the transmission signal and for outputting the compensated transmission signal. The distortion compensation amplifier includes a storage unit that stores therein distortion compensation coefficients; a processor that performs distortion compensation processing on the transmission signal by using one of the distortion compensation coefficients; and an amplifier that amplifies the transmission signal that has been subjected to the distortion compensation processing; wherein the processor calculates an average value of the distortion compensation coefficients stored in the storage unit, and calculates the distortion compensation coefficient on the basis of the transmission signal, and the average value. | 02-16-2012 |
20120110527 | CONNECTION VERIFICATION METHOD, RECORDING MEDIUM THEREOF, AND CONNECTION VERIFICATION APPARATUS - A connection verification method is disclosed. A computer verifies a connection between a first node and a second node by starting from the first node in a designed integrated circuit, based on connection information stored in a storage part. The computer detects whether a module connected to the second node is a predetermined module predetermined module having a logic condition therein, based on connection relationship logic information stored in the storage part. The computer conducts a connection verification starting the module to verify a connection between the module and a third node when the module is the predetermined module. | 05-03-2012 |
20120147991 | DISTORTION COMPENSATION DEVICE, DISTORTION COMPENSATION METHOD AND WIRELESS APPARATUS - A distortion compensation device includes a storage unit storing a plurality of distortion compensation coefficients associated with power values of transmission signals, a distortion compensation processing unit acquiring a distortion compensation coefficient corresponding to a power value of a received transmission signal from among the plurality of distortion compensation coefficients and subjecting the received transmission signal to a distortion compensation process on the basis of the acquired distortion compensation coefficient, a phase calculating unit calculating a phase correction value on the basis of the distortion compensation coefficients, a phase correcting unit generating a reference signal by correcting a phase of the received transmission signal on the basis of the phase correction value, and a correction processing unit performing a correction process for the transmission signal subjected to the distortion compensation process on the basis of the reference signal and a feedback signal from a transmission power amplifier. | 06-14-2012 |
20120250738 | RADIO APPARATUS, RADIO APPARATUS CONTROLLER, AND SYNCHRONIZATION ESTABLISHING METHOD - A radio apparatus includes: first and second reception units to receive first and second signals from first and second radio apparatus controllers, respectively; first and second synchronous clock generation units to generate first and second recovery clocks from clock components included in the first and second signals received by the reception units, respectively; a clock synchronization detection unit to detect whether or not the second recovery clock is synchronous with the first recovery clock; a code selection unit to select a code indicating the synchronous state according to a detection result of the synchronization detection unit; a signal processing unit of generate a third signal to which the code selected by the code selection unit is added and which is synchronous with the first recovery clock; and a transmission unit to transmit the third signal generated by the signal processing unit to the second radio apparatus controller. | 10-04-2012 |
20130083866 | DISTORTION COMPENSATOR AND DISTORTION COMPENSATION METHOD - A distortion compensator compensates for distortion of a signal caused by an amplifier. A storage section stores a plurality of compensation coefficients used for distortion compensation. A selection section selects a compensation coefficient corresponding to an index value indicative of a power level of the signal from among the plurality of compensation coefficients. The selection section determines whether or not the power level is higher than a threshold, and uses, based on a determination result, a first index value calculated without using a logarithmic operation or a second index value calculated by using a logarithmic operation. | 04-04-2013 |
20130084810 | RECEIVING APPARATUS, BASE STATION APPARATUS AND METHOD FOR REDUCING INTERFERENCE WAVE - A receiving apparatus includes: an interference wave reducer configured to reduce an interference wave included in a received signal; and an automatic gain controller configured to automatically control a gain for the received signal, the automatic gain controller including a convergence time saver to save convergence time of an automatic gain control for the received signal based on an input of an interference wave. | 04-04-2013 |
20130243125 | TRANSMISSION APPARATUS AND TRANSMISSION METHOD - A transmission apparatus includes a signal processing unit to perform a distortion compensation process on a transmitting signal based on a distortion compensation coefficient, and an updating unit to update a transmission power of the transmitting signal subjected to the distortion compensation process in certain processes, to transmit the transmitting signal at the updated transmission power. The signal processing unit may set a referring range of the distortion compensation coefficient stored in a storage unit, based on the transmitting signal before performing the distortion compensation process and the transmitting signal having the transmission power thereof updated by the updating unit. | 09-19-2013 |
20130259154 | WIRELESS APPARATUS AND DISTORTION COMPENSATING METHOD - A wireless apparatus includes amplifying systems each including a storing unit storing a distortion compensation coefficient for compensation for a nonlinear distortion of one or more transmission signals, a compensator compensating for the nonlinear distortion using the distortion compensation coefficient stored in the storing unit, and an amplifier amplifying the transmission signal after distortion compensation. The wireless apparatus further includes a switch that selects feedback signals corresponding to the transmission signals output from the amplifying systems, a subtractor that derives one or more differences between the feedback signal selected in the switch and the transmission signal, a first calculator that derives a distortion compensation coefficient that restricts the difference derived in the subtractor, and a switch controller that controls a length of time during which the feedback signal is selected in the switch depending on magnitude of distortion of the transmission signal output from the amplifying system. | 10-03-2013 |
20130321078 | DISTORTION COMPENSATION APPARATUS AND DISTORTION COMPENSATION METHOD - A distortion compensation apparatus including: a processor configured to generate a pre-distortion signal by compensating an input signal for a distortion based on a distortion compensation coefficient and a plurality of delayed signals obtained by delaying the input signal by a plurality of amounts of delay, and an amplifier configured to generate an amplified signal by amplifying the pre-distortion signal, wherein the processor calculates the distortion compensation coefficient based on the input signal, the pre-distortion signal, and the amplified signal, and calculates the plurality of amounts of delay based on the amplified signal. | 12-05-2013 |
20140003554 | DISTORTION COMPENSATING DEVICE AND DISTORTION COMPENSATING METHOD | 01-02-2014 |
20140106692 | TRANSMISSION APPARATUS, OUTPUT CONTROL METHOD FOR TRANSMISSION APPARATUS AND TRANSMISSION SYSTEM - A transmission apparatus includes: an amplifier configured to amplify a transmission signal; a calculation unit configured to calculate a standing-wave ratio based on the transmission signal and a signal from an antenna to the amplifier; and a controller configured to switch a state of the amplifier based on the state of the amplifier and the standing-wave ratio. | 04-17-2014 |
20140145788 | DISTORTION COMPENSATION DEVICE AND DISTORTION COMPENSATION METHOD - A distortion compensation device includes a storage unit, an address generator, and a distortion compensation processor. The storage unit stores therein a distortion compensation coefficient for compensating distortion generated in an amplifier for amplifying an input signal. The address generator generates a first address based on a power value of the signal at a current time. Furthermore, the address generator delays, every time a new augend is input, the sum of the power value of the signal at the current time and the augend. The address generator generates a second address based on the sum obtained by calculating a new augend, from the delayed sum. The distortion compensation processor acquires a distortion compensation coefficient corresponding to a combination of the first address and the second address from the storage unit and performs distortion compensation processing on the signal by using the acquired distortion compensation coefficient. | 05-29-2014 |
20140146910 | DELAY QUANTITY ESTIMATION APPARATUS AND DELAY QUANTITY ESTIMATION METHOD - A delay quantity estimation apparatus comprises a first correlation value arithmetic unit to calculate a first correlation value as a correlation value between a first input signal and a feedback signal delayed with a first delay value; a second correlation value arithmetic unit to calculate a second correlation value as a correlation value between the first input signal and a feedback signal delayed with a second delay value; and a delay quantity estimation unit to estimate a delay quantity of the feedback signal with respect to the input signal on the basis of the first difference value as a difference between the first correlation value and the second correlation value, wherein the second delay value is a value given by adding a certain value to the first delay value. | 05-29-2014 |
20150077180 | DISTORTION COMPENSATION APPARATUS AND DISTORTION COMPENSATION METHOD - A distortion compensation apparatus includes: a storage unit that stores a distortion compensation coefficient; a distortion-compensation-coefficient selecting unit that takes a logarithm of power of an input signal and exponentiates a value obtained by taking the logarithm, and that selects a distortion compensation coefficient that is stored in the storage unit according to a value obtained by the exponentiating; a distortion-compensation processing unit that acquires the selected distortion compensation coefficient from the storage unit, and that performs distortion compensation processing on the input signal to the distortion-compensation-coefficient selecting unit using the acquired distortion compensation coefficient; an amplifier that amplifies the signal subjected to the distortion compensation processing; and a distortion-compensation-coefficient updating unit that updates the distortion compensation coefficient stored in the storage unit based on the amplified signal and the input signal to the distortion-compensation-coefficient selecting unit. | 03-19-2015 |