Patent application number | Description | Published |
20080287077 | Method and apparatus for cartesian error feedback - A method of reducing distortion in the output of an amplifier is provided. The method comprises subtractively combining baseband error signals with the appropriate phase shift with baseband input signals, the baseband error signals generated by subtractively combining delayed fed-forward portions of the baseband input signals with baseband converted portions of a fed-back amplified output signal, the amplified output signal being a distorted replica of combined up-converted baseband input signals. The baseband error signals being filtered prior to the combining function, and also providing inputs to a controller which adjusts active elements of the amplification and fed-back paths in order to minimize the distortion within the output of the amplifier. | 11-20-2008 |
20080290939 | Method and apparatus for distortion correction of RF amplifiers - A method of reducing distortion in the output of an amplifier is provided. The method comprises subtractively combining baseband error signals with the appropriate phase shift with baseband input signals, the baseband error signals generated by subtractively combining delayed fed-forward portions of the baseband input signals with baseband converted portions of a fed-back amplified output signal, the amplified output signal being a distorted replica of combined up-converted baseband input signals. The baseband error signals being filtered prior to the combining function, and also providing inputs to a controller which adjusts active elements of the amplification and fed-back paths in order to minimize the distortion within the output of the amplifier. | 11-27-2008 |
20080297247 | Method and apparatus for distortion correction of RF amplifiers - A method of reducing distortion in the output of an amplifier is provided. The method comprises subtractively combining an error signals with the appropriate phase shift with input signals to be amplified. The error signal being generated by subtractively combining a fed-forward portion of the input signal with a portion of the fed-back amplified output signal, and signal processing applied to it between its generation and application to correcting the input signal in the baseband domain. The error therefore being down-converted, filtered, and up-converted in the feedback path. The filtered baseband error signal components providing inputs to a controller which adjusts active elements of the amplification and feedback path in order to minimize the distortion within the output of the amplifier. | 12-04-2008 |
20080298501 | Method and apparatus for distortion correction of RF amplifiers - A method of reducing distortion in the output of an amplifier is provided. The method comprises subtractively combining an error signals with the appropriate phase shift with input signals to be amplified. The error signal being generated by subtractively combining a fed-forward portion of the input signal with a portion of the fed-back amplified output signal, and signal processing applied to it between its generation and application to correcting the input signal in the baseband domain. The error therefore being down-converted, filtered, and up-converted in the feedback path. The filtered baseband error signal components providing inputs to a controller which adjusts active elements of the amplification and feedback path in order to minimize the distortion within the output of the amplifier. | 12-04-2008 |
20090325527 | DUAL BAND AMPLIFIER - A dual band amplifier is provided comprising a first matching circuit disposed in a first radiofrequency path between an input port and a first amplifier and a second matching circuit disposed in a second radiofrequency path between the input port and a second amplifier. The first matching circuit transforms a first input impedance of the first amplifier to a predetermined input port impedance when the radiofrequency signal is in a first frequency range and transmits the first input impedance to the input port when the radiofrequency signal is in the second frequency range. The second matching circuit transforms the second input impedance to the input port impedance when the input signal is in the second frequency range and transmits the second input impedance to the input port when the radiofrequency signal is in the first frequency range. | 12-31-2009 |
20110248703 | Power Detector and Method for Detecting Power - A circuit and method are provided for detecting a power of a signal amplified in a power amplifier. A diode and a voltage bias source are used to shift a voltage of the signal taken at a base of an amplifying transistor of the power amplifier, to generate a positive signal. The positive signal is provided to a base input of an emitter follower exhibiting high input impedance to generate a power detector output which follows the positive signal. | 10-13-2011 |
20130063215 | DUAL BAND AMPLIFIER - A dual band amplifier is provided comprising a first matching circuit disposed in a first radiofrequency path between an input port and a first amplifier and a second matching circuit disposed in a second radiofrequency path between the input port and a second amplifier. The first matching circuit transforms a first input impedance of the first amplifier to a predetermined input port impedance when the radiofrequency signal is in a first frequency range and transmits the first input impedance to the input port when the radiofrequency signal is in the second frequency range. The second matching circuit transforms the second input impedance to the input port impedance when the input signal is in the second frequency range and transmits the second input impedance to the input port when the radiofrequency signal is in the first frequency range. | 03-14-2013 |