High efficient super linear DFFA digital ground television transmitter

Abstract

The invention relates to a high efficient ultralinear high speed self-adapting and self-healing controlled digital terrestrial television. The invention adopts multiple structures of single ring type, double ring type, double signals cancellation balanced three ring type, double distortions balanced three ring type and double signals double distortions balanced four ring type to realize ultralinear amplification; it adopts multiple DOHERTY self-adapting high efficient matching technology of temperature compensation attenuation, linear temperature compensation and two stage, three stage replacement type, four stage replacement type, parallel connection type, parallel connection replacement type, and tandem type to realizes high stable high efficient amplification; it adopts microprocessor interpolation method, searching list wide range optimizing and auto-locking high speed self- adapting control vector modulator to realize the precise, wide rang, stable balanced and high speed self-adapting control to the signals, deformation ring and Dohert matching; it adopts double tone IQ modulation demodulation high restrain to realize the pure abstraction of control signal; it adopts IQ demodulation mean square root operation to realize detection to the signal with small deformation; and it detects the working state in real time, alarms while it is abnormal and can eliminates the abnormity by self-healing regulation.

Description

Technical field: [0001] The invention relates to a digital terrestrial television transmitter technology, in particular to a high-efficiency super-linear DFFA (Doherty & Feed Forward Linear Power Amplifiers) digital terrestrial television transmitter technology. Background technique: [0002] Modern digital terrestrial TV transmission adopts XQAM and OFDM modulation technology. Its core technology requires high-efficiency, high-linearity and high-stable broadband high-power amplification under peak-to-average ratio signal conditions. Digital terrestrial TV transmission belongs to wide-area coverage. Generally, the power of wireless communication is much larger, and the average power of AVG is generally 50W-1000W. [0003] The existing DPD digital pre-distortion power amplification technology can improve the linearity, and the combination of Doherty technology can greatly improve the efficiency, but the DPD digital pre-distortion power amplification technology has the problem...

AI Technical Summary

Problems solved by technology

In order to facilitate the extraction of the self-locking control signal, the pilot signal is used to simulate the distorted signal. In order to better realize the extraction of the self-locking control signal, it can modulate two audio signals on the pilot signal in the form of IQ modulation, thereby increasing The anti-out-of-band interference ability when extracting the self-locking control signal is improved; when the distortion is canceled, it adopts the residual pilot frequency mixing filter and the IQ demodulation root mean square operation to solve the residual pilot detection of the existing feedforward adaptive power amplifier difficult problem; it can add a signal cancellation loop at low cost to further improve signal cancellation on the basis of double-loop feedforward technology, so as to reduce the distortion amplification power of the distortion cancellation loop, and add a distortion cancellation loop at low cost to further improve linearity Spend

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