KR950030659A - Digital carrier recovery device for high definition television receiver - Google Patents

Abstract

Digital carrier recovery apparatus of HDTV receiver has been suggested. The digital carrier recovery apparatus includes tuning means for selecting one of a plurality of received RF signals, converting the selected RF signal into an intermediate frequency signal, and outputting the intermediate frequency signal; A / D conversion means for converting an intermediate frequency signal into a digital signal, an oscillation means for generating a digital sine signal, and performing a predetermined algorithm in a digital manner to synchronize the frequencies and phases of the digital sine signal and the digitalized intermediate frequency signal with each other. And digital FPLL means for outputting a digital loop control signal.

Description

Digital carrier recovery device for high definition television receiver

Since this is an open matter, no full text was included.

FIG. 1 is a block diagram showing a carrier recovery apparatus of a conventional HDTV receiver, FIG. 7 is a block diagram showing a carrier recovery apparatus of a conventional HDTV receiver for removing interference from NTSC video broadcasting waves, and FIG. 8 is a block diagram of a HDTV receiver according to the present invention. Fig. 9 is a block diagram showing the first embodiment of the carrier recovery apparatus. Fig. 9 is a block diagram showing the second embodiment of the carrier recovery apparatus of the HDTV receiver according to the present invention.

Claims (7)

Tuning means 100 for selecting one of the plurality of received RF signals and converting the carrier frequency of the selected RF signal according to the input loop control signal, and converting the intermediate frequency signal to output the digital signal A. / D conversion means 200, oscillation means 300 for generating a digital sine signal, and performing a predetermined algorithm in a digital manner to synchronize the frequency and phase of the digital sine signal and the digitalized intermediate frequency signal to each other. A digital carrier recovery device for a high definition television receiver, characterized by comprising a digital FPLL means (400) for outputting a digital loop control signal. 2. A predetermined low frequency band signal of the output signal of the digital FPLL means 400 according to claim 1 The digital FPLL 500 passing through the bay and the output signal of the digital FPLL 500 are converted into digital signals to generate a loop control signal for voltage controlled oscillation, and the D / A converting means 600 for providing the tuning means 100 Digital carrier recovery device of the high-definition television receiver further comprises. The method of claim 1, wherein the tuning means 100 is selected from the antenna 100a for receiving a plurality of RF signals, one of the plurality of received RF signals, and inputs the loop control signal as a voltage controlled oscillation signal. A tuner 100b for converting a carrier of the selected RF signal into an intermediate frequency signal, and a voltage controlled oscillator 100c for providing a voltage controlled oscillation signal to the tuner 100b according to the input loop control signal for voltage controlled oscillation. Digital carrier recovery device of high definition television receiver The FPLL of claim 1, wherein the FPLL phase shifts the digital information signal from the oscillation unit 300 by a predetermined angle and outputs the phase shifter 400A and the digital intermediate frequency signal and phase output from the A / D conversion unit 200. The first multiplier 400b and the A / D converting means 200 which multiply the digital sinusoidal signals of the oscillation means 300 phase shifted by the shifter 400a to produce the digital beat signal I (n) of the I channel. The second multiplier 400c for multiplying the digital intermediate frequency signal from the digital signal with the digital sinusoidal signal from the oscillation means 300 to form the digital bit signal Q (n) of the Q channel, and the digital bit signal I of the I channel. a first digital LPF 400f for passing only a pilot signal including an HDTV carrier from n), a delay element 400e for delaying and outputting a pilot signal output from the digital LPF 400d by a predetermined time (nd), and Q HD from digital bit signal Q (n) of channel A second digital LPF 400f for passing only a pilot signal including a TV carrier, a third multiplier 400g for multiplying the output signal of the delay element 400e with the output signal of the second digital LPF 400f, and a delay element ( A differential detector 400h for detecting and outputting a difference between the current output signal of 400e) and the immediately preceding output signal; And a fourth multiplier (400i) for multiplying the output signal of the third multiplier (400g) and the differential detector (400h) and outputting the result as a loop control signal. The FPLL means 400 is connected between the delay element 400e and the third multiplier 400g to obtain a numerically controlled oscillation loop control signal from the FPLL means 400. And a quantizer (400k) for outputting a signal of +1 or -1 in accordance with the sign of the output signal of 400e). 5. The apparatus of claim 4, wherein the predetermined delay time (nd) of the delay element (400e) is determined in consideration of the maximum frequency shift. The digital frequency of the high-definition television receiver of claim 1, wherein the sampling frequency of the A / D conversion means 200 is upsampled at a frequency four times higher than that of the intermediate frequency signal output from the tuning means 100. Carrier recovery device. ※ Note: This is to be disclosed by the original application.