Patent application number | Description | Published |
20090137218 | WIRELESS COMMUNICATION APPARATUS, POWER AMPLIFIER CONTROL METHOD, AND POWER AMPLIFIER CONTROL APPARATUS - In a wireless communication apparatus in a time division duplex system, a transmission signal generation unit generates a transmission signal. A power amplifying device amplifies the generated transmission signal. A control signal generation device generates a drain voltage control signal for control of the drain voltage of the power amplifying device, and a gate voltage control signal for control of the gate voltage of the power amplifying device. The switch unit switches off the drain power supply of the power amplifying device during reception in the time division duplex system according to the drain voltage control signal. In addition, the power amplifying device sets a higher gate voltage during reception in the time division duplex system higher than during transmission according to the gate voltage control signal. | 05-28-2009 |
20100014609 | DISTORTION CORRECTION CONTROL APPARATUS AND DISTORTION CORRECTION CONTROL METHOD - A distortion correction control apparatus is for compensating for a burst distortion in a transmission amplifier caused by a burst of an input signal of a transmission target. The apparatus includes a holding unit that stores a distortion correction coefficient having reverse characteristics to the burst distortion; a unit that multiplies the distortion correction coefficient read out from the holding unit by the input signal or adds the distortion correction coefficient read out from the holding unit to the input signal, upon reception of burst information notifying of switching between presence and absence of the input signal; and an update unit that updates, based on the input signal, the distortion correction coefficient of the last time, and a signal fed back as an output signal of the transmission amplifier, the distortion correction coefficient by an adaptive algorithm, and that inputs the updated distortion correction coefficient to the holding unit. | 01-21-2010 |
20100062733 | DISTORTION CORRECTION CONTROL APPARATUS AND DISTORTION CORRECTION CONTROL METHOD - A distortion correction control apparatus is for compensating for a burst distortion of a transmission amplifier caused by a burst of an input signal of a transmission target. The apparatus includes a generation unit that generates a distortion correction coefficient having reverse characteristics to the foregoing burst distortion; a unit that multiplies the distortion correction coefficient output from the generation unit by the input signal or adds the distortion correction coefficient output from the generation unit to the input signal, upon reception of burst information notifying of switching between presence and absence of the input signal; and an update unit that updates, based on the input signal and a branch signal fed back as an output signal of the transmission amplifier, parameters of functions used for adaptively generating the distortion correction coefficient, and that inputs the updated parameters to the generation unit. | 03-11-2010 |
20100182214 | Variable Directional Antenna - A variable directional antenna by means of a microstrip antenna and reactance change. The variable directional antenna has a structure to reduce sidelobes occurring when an element interval is reduced, and is structured in a three-element plane, having a feeding element and non-feeding elements provided at both sides of the feeding element. Each of the non-feeding elements provided at both sides of the feeding element has two split non-feeding elements two-divided into sizes of 1:2 in the lateral direction. The split non-feeding element divided into the size 1 is provided closer to the feeding element, and a reactance variable part is connected with the split non-feeding element divided into the size of 2. Alternatively, each of the non-feeding elements provided at both sides of the feeding element has two split non-feeding elements two-divided into sizes of 2:1 in the lateral direction. The split non-feeding element divided into the size 2 is provided closer to the feeding element, and the reactance variable part is connected either with the split non-feeding element divided into the size of 2 or the split non-feeding element divided into the size 1. | 07-22-2010 |
20100188169 | Reactance Varying Device - A reactance varying device comprises a voltage-controlled variable-capacitance circuit, a biasing circuit and an impedance transformer. The biasing circuit has a virtual AC ground node, which acts as a gateway to supply a bias voltage to the variable-capacitance circuit. The impedance transformer separates the variable-capacitance circuit from the AC ground node, as well as provides an inductive element to form a reactance varying LC tank. | 07-29-2010 |
20110260792 | DISTORTION COMPENSATION DEVICE, RADIO COMMUNICATION DEVICE, AND DISTORTION COMPENSATION METHOD - A distortion compensation device includes a distortion compensation unit which compensates for a distortion generated in a power amplifier by using a polynomial in which a signal to be input into a power amplifier is raised to a power of a degree N (N is an integer larger than 0) and the raised signal is delayed by a delay number K (K is an integer larger than 0), and a polynomial adjusting unit which adjusts the degree N or the delay number K of the polynomial based on a comparison between a prescribed value, which indicates a degree of variation of the distortion generated in the power amplifier and a threshold value. | 10-27-2011 |
20110284643 | RFID Tag And Manufacturing Method Thereof - An RFID tag having a tag antenna and an LSI chip, comprising: a power-supply pattern on which the LSI chip is mounted; a patch antenna that functions as the tag antenna; and a high-frequency connection section that makes a high-frequency connection between the power-supply pattern and the patch antenna. The high-frequency connection section is formed, for example, by forming a slot in the patch antenna, layering one end of a small dipole antenna that functions as the power-supply pattern over the slot so that it crosses over the slot, and supplying power from the smalI dipole antenna to the patch antenna. | 11-24-2011 |
20120068768 | TRANSMISSION APPARATUS AND DISTORTION COMPENSATION METHOD - A transmission apparatus includes an analog digital converter that performs sampling on a demodulated signal obtained by demodulating a part of an output signal, which is produced by amplifying a modulated signal of a baseband signal including a plurality of signals having frequencies separated from each other, at a sampling frequency lower than a frequency of a given intermodulation distortion component and converting the demodulated signal into a digital signal, a detection section that detects an aliasing component of the given intermodulation distortion component produced by the conversion of the analog digital converter, and a distortion compensation section that compensates an input signal to be modulated for the given intermodulation distortion component in accordance with the detected aliasing component. | 03-22-2012 |