Abstract:
A RF-digital hybrid mode power amplifier system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier in the RF domain. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers and multi-channels. As a result, the digital hybrid mode power amplifier system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems, where baseband I-Q signal information is not readily available.
Abstract:
An envelope tracking power amplifier system comprising an RF input path and an envelope path for providing a modulated power amplifier supply, further comprising a plurality of envelope detectors for detecting the envelope of a plurality of frequency bands of an input signal and each generating an output signal, and a combiner for combining the output of the envelope detectors.
Abstract:
Various digital pre-distortion systems for use in transmitters are disclosed. The digital pre-distortion system comprises an observing path, which performs either undersampling or radio frequency sampling of the output of a power amplifier. Undersampling may be performed at a rate, which causes aliasing to occur in the undersampled frequency domain. Both undersampling and radio frequency sampling reduces the complexity of the digital pre-distortion system by removing any down mixing modules or anti-aliasing modules, while maintaining reasonable performance of the digital pre-distortion systems.
Abstract:
A RF-digital hybrid mode power amplifier system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier in the RF domain. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers and multi-channels. As a result, the digital hybrid mode power amplifier system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems, where baseband I-Q signal information is not readily available.
Abstract:
A remote radio head unit (RRU) system for multiple operating frequency bands, multi-channels, driven by a single or more wide band power amplifiers. More specifically, the present invention enables multiple-bands RRU to use fewer power amplifiers in order to reduce size and cost of the multi-band RRU. The present invention is based on the method of using duplexers and/or interference cancellation system technique to increase the isolation between the transmitter signal and receiver signal of the RRU.
Abstract:
Methods and systems for vector combining power amplification are disclosed herein. In one embodiment, a plurality of signals are individually amplified, then summed to form a desired time-varying complex envelope signal. Phase and/or frequency characteristics of one or more of the signals are controlled to provide the desired phase, frequency, and/or amplitude characteristics of the desired time-varying complex envelope signal. In another embodiment, a time-varying complex envelope signal is decomposed into a plurality of constant envelope constituent signals. The constituent signals are amplified equally or substantially equally, and then summed to construct an amplified version of the original time-varying envelope signal. Embodiments also perform frequency up-conversion.
Abstract:
In a wireless communication apparatus of the present invention for transmitting a modulated signal using multi-carriers, a bias voltage of a power amplifier (101) for amplifying the modulated signal is controlled by control units (10, 102) according to the number of carriers in the modulated signal so as to reduce power consumption.
Abstract:
A radio frequency (RF) amplifier system includes an RF power amplifier having an input and an output, and a typical gain of 1000 or more between the input and the output. An adaptive feedback channel is coupled between the input and the output of the RF power amplifier. The adaptive feedback channel receives as inputs audio signals for modulation of the input of the RF power amplifier, a frequency command word indicative of a desired frequency and phase of the RF amplifier system, and a control word indicative of a desired power level of the output of the RF power amplifier and of a mode of operation of the RF amplifier system. In response to the inputs, the adaptive feedback channel provides as an output a degenerative feedback signal to the input of the RF power amplifier.
Abstract:
In a network employing code division multiplex access, a distortion compensation amplifying apparatus is provided which is capable of making quick response to carry out the distortion compensation with high accuracy even if the signal power to be inputted thereto varies rapidly. In this distortion compensation amplifying apparatus, the renewal of a distortion compensation coefficient in a renewing unit is complemented on the basis of a result of amplification in an amplifier with respect to a signal code-division-multiplexed in a pseudo-signal multiplexing unit.
Abstract:
An envelope tracking power amplifier system comprising an RF input path and an envelope path for providing a modulated power amplifier supply, further comprising a plurality of envelope detectors for detecting the envelope of a plurality of frequency bands of an input signal and each generating an output signal, and a combiner for combining the output of the envelope detectors.