| Patent application number | Description | Published |
| 20080198949 | RECEIVER, WIRELESS DEVICE AND METHOD FOR CANCELLING A DC OFFSET COMPONENT - A receiver includes a memory for storing DC offset amounts generated by an analog circuit; an amplifier; a DC offset amount generator for generating a first offset value and a second offset value to be removed from the received signal amplified at the amplifier; a first DC offset component-removing unit for removing the first DC offset value from the received signal before the amplifier; a second DC offset component-removing unit for removing the second DC offset value from the received signal after the amplifier; and an updating unit for updating the DC offset amount stored in the memory in view of the second DC offset value generated by the DC offset amount generator. A maximum value of the second DC offset value is set larger than a multiplication value of a gain of the amplifier by a minimum resolution value of the first DC offset value. | 08-21-2008 |
| 20080233906 | FREQUENCY CONVERTER, RADIO RECEIVER - Disclosed is a frequency converter including: a passive type analog multiplier configured to output a multiplication result in a current; a buffer outputting a buffering current by buffering the current of the multiplication result; and a current-voltage converter current-voltage converting the buffering current. Alternately, disclosed is a frequency converter including: a passive type analog multiplier configured to output a multiplication result in a current; a buffer outputting a buffering current by buffering the current of the multiplication result; and an integrator integrating the buffering current to output a voltage. | 09-25-2008 |
| 20080274714 | AMPLIFIER, FILTER USING THE SAME, AND RADIO COMMUNICATION DEVICE - An amplifier includes an amplification unit which amplify a first difference between first and second input signals, a second difference between second and third input signals and a third difference between third and first input signals by a differential mode gain, and amplify an average of the first, second and third input signal by a common mode gain, for outputting a first output signal corresponding to a sum of the amplified first difference and the amplified average, a second output signal corresponding to a sum of the amplified second difference and the amplified average, and a third output signal corresponding to a sum of the amplified third difference and amplified average; first, second; and a reduction circuit which reduces the common mode gain less than the differential mode gain. | 11-06-2008 |
| 20080309436 | MULTI-INPUT MULTI-OUTPUT AMPLIFIER, AN ACTIVE INDUCTOR, A FILTER AND A RADIO COMMUNICATION DEVICE - A non-inverting amplifier includes n external input terminals which receive n (n≧3) input voltage signals having a constant sum of voltages, respectively, n amplification units each including n−1 internal input terminals connected to n−1 terminals of the n external input terminals in a different combination for each of the amplification units, n−1 voltage-to-current converters which convert input voltage signals from the internal input terminals into current signals, and a load which converts an added current signal obtained by adding up the current signals into an output voltage signal, and n external output terminals which output n output voltage signals from the n amplification units. | 12-18-2008 |
| 20090111377 | FREQUENCY CONVERTER AND RECEIVER AND TRANSMITTER USING THE SAME - A frequency converter includes a voltage-current converter circuit which generates a positive-phase input current signal and a negative-phase input current signal, a switching circuit which switches between the positive-phase input current signal and the negative-phase input current signal according to a positive-phase local oscillator signal and a negative-phase local oscillator signal to generate a positive-phase output current signal and a negative-phase output current signal, an amplifier circuit which current-voltage converts and amplifies the positive-phase output current signal and negative-phase output current signal to generate a positive-phase output voltage signal and a negative-phase output voltage signal, and a plurality of CR circuits which are inserted at least either between the voltage-current converter circuit and the switching circuit or between the switching circuit and the amplifier circuit and each of which includes at least one capacitor through which high-frequency components pass and at least one resistance through which low-frequency noise components pass. | 04-30-2009 |
| 20090302949 | BIAS CIRCUIT AND AMPLIFIER USING THE SAME - A bias circuit including: a first current source which generates a first current; a second current source which generates a second current having a temperature-to-output current characteristic that an output current characteristic increases or decreases with a change in temperature to intersect with that of the first current; a first current-voltage conversion circuit which converts the first current to a first voltage; a second current-voltage conversion circuit which has an input terminal and converts a current inputted into the input terminal to a second voltage; a comparison circuit which compares the first voltage and the second voltage and generates a third current according to a result of the comparison; an addition unit which adds the third current to the second current and inputs a resulting current to the input terminal; and a voltage-current conversion circuit which converts the second voltage to a fourth current for bias. | 12-10-2009 |