Digital wave carrying restoring device

A digital carrier and coefficient technology, applied in the field of digital carrier recovery devices, can solve problems such as the difficulty in ensuring the accuracy of the Ο€/2 analog phase-shifting network, the difficulty in obtaining sin signals, and the performance being greatly affected by the environment, so as to improve work reliability and practicality. The effect of speeding up the filter locking speed and reducing the difficulty of system design
CN1235377CInactive Publication Date: 2006-01-04HISILICON TECH
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Patent Information

Authority / Receiving Office
CN Β· China
Patent Type
Patents(China)
Current Assignee / Owner
HISILICON TECH
Publication Date
2006-01-04
Estimated Expiration
Not applicable Β· inactive patent

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Abstract

A digital carrier restoring device relating to digital information transmission includes an A / D sampler and a digital carrier restoring phase-locking ring containing: a phase rotator, a carrier detector, a judger, a loop filter, and a digit control oscillator in which, the A / D sampler is to sample IF cross amplitude modulation signals from RF receiver to convert analog signals to digital signals, the phase rotator carrying out vector rotating to baseband signals, a digit control oscillator provides the rotating angle, the carrier detector computer the angles difference according to the signal angle difference, the loop filter filters the angle difference value signals and gets control signal of a rotating angle and the digital control oscillator accumulates the roting angle control signal to output the angle by subtracting a standard mode.
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Description

technical field

[0001] The invention relates to the transmission of digital information, in particular to a digital carrier recovery device. Background technique

[0002] In the existing digital video broadcasting, the video signal is usually transmitted by means of quadrature amplitude modulation QAM (Quadrature Amplitude Modulation), but because the modulated signal is a baseband signal, it must be modulated into a radio frequency signal by carrier modulation to pass After the digital video broadcasting receiver receives the radio frequency signal, it must also remove the modulated carrier to extract the baseband signal, and then demodulate the baseband signal to obtain the original video transmission signal. The current carrier removal (recovery scheme) generally adopts an analog circuit or a circuit mixed with digital and analog.

[0003] In the digital video broadcasting system, the quadrature amplitude modulation QAM baseband data signal must first be modulated by hig...

Claims

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