Apparatus and method for corresponding frequency synchronization in on-channel repeater
First Claim
1. A frequency synchronizing apparatus for an on-channel repeater receiving signals on one channel and distributing the signals on the same channel, comprising:
- a carrier recovery means for compensating a carrier frequency error of a receiving signal;
a timing recovery means for compensating a sampling timing error of the receiving signal;
a carrier error reflecting means for reflecting the carrier frequency error extracted from the carrier recovery means to a transmitting signal;
a timing error reflecting means for reflecting the sampling timing error extracted from the timing recovery means to the transmitting signal; and
wherein the timing error reflecting means includes;
a numerically controlled oscillator for converting the sampling timing phase error extracted from the timing recovery means into a sample rate;
an inverse converter for obtaining an inverse value of the converted sample rate; and
a resampler for resampling the transmitting signal according to the inverse value of the sample rate.
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Accused Products
Abstract
Provided is a frequency synchronizing apparatus and method that can synchronize frequencies between receiving signals and transmitting signals by extracting a carrier error and sampling timing error information in a synchronization process of the receiving signal from a main transmitter or another repeater and reflecting them in the transmitting signal in an on-channel repeater. The apparatus includes a carrier recovery means for compensating a carrier frequency error of a receiving signal; a timing recovery means for compensating a sampling timing error of the receiving signal; a carrier error reflecting means for reflecting the carrier frequency error extracted from the carrier recovery means to a transmitting signal; and a timing error reflecting means for reflecting the sampling timing error extracted from the timing recovery means to the transmitting signal. The present invention is used to form an on-channel repeating network in any transmission system including a digital television broadcasting system.
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Citations
20 Claims
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1. A frequency synchronizing apparatus for an on-channel repeater receiving signals on one channel and distributing the signals on the same channel, comprising:
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a carrier recovery means for compensating a carrier frequency error of a receiving signal; a timing recovery means for compensating a sampling timing error of the receiving signal; a carrier error reflecting means for reflecting the carrier frequency error extracted from the carrier recovery means to a transmitting signal; a timing error reflecting means for reflecting the sampling timing error extracted from the timing recovery means to the transmitting signal; and wherein the timing error reflecting means includes; a numerically controlled oscillator for converting the sampling timing phase error extracted from the timing recovery means into a sample rate; an inverse converter for obtaining an inverse value of the converted sample rate; and a resampler for resampling the transmitting signal according to the inverse value of the sample rate. - View Dependent Claims (2, 3, 4, 5)
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6. A frequency synchronizing apparatus for an on-channel repeater receiving signals on one channel and distributing the signals on the same channel, comprising:
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a carrier recovery means for compensating a carrier frequency error of a receiving signal; a timing recovery means for compensating a sampling timing error of the receiving signal; a carrier error reflecting means for reflecting the carrier frequency error extracted from the carrier recovery means to a transmitting signal; a timing error reflecting means for reflecting the sampling timing error extracted from the timing recovery means to the transmitting signal; and wherein the carrier error reflecting means includes; a frequency inverter for inverting the sign of the carrier frequency error outputted from a numerically controlled oscillator of the carrier recovery means; and a frequency converter for shifting the carrier frequency of the transmitting signal as much as the sign-inverted carrier frequency error.
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7. A frequency synchronizing apparatus for an on-channel repeater receiving signals on one channel and distributing the signals on the same channel, comprising:
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an analog-digital converting means for converting an analog receiving signal into a digital signal; a carrier recovery means for compensating a carrier frequency error of the digital signal; a timing recovery means for compensating a sampling timing error of the digital signal; a carrier error reflecting means for reflecting the carrier frequency error extracted from the carrier recovery means to a transmitting signal; a digital-analog converting means for converting the transmitting signal reflected with the carrier frequency error into an analog signal; and a voltage controlled oscillator for reflecting the sampling timing error extracted from the timing recovery means to an oscillation signal and providing the oscillation signal to the analog-digital converting means and the digital-analog converting means. - View Dependent Claims (8, 9, 10)
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11. A frequency synchronizing method for an on-channel repeater receiving signals on one channel and distributing the signals on the same channel, comprising the steps of:
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a) compensating a carrier frequency error of a receiving signal; b) compensating a sampling timing error of the receiving signal; c) reflecting the carrier frequency error extracted in the step (a) to a transmitting signal; d) reflecting the sampling timing error extracted in the step (b) to the transmitting signal; and wherein the step d) includes the step of; d1) converting the sampling timing phase error detected in the step b) into a sample rate; d2) obtaining an inverse value of the sample rate; and d3) resampling the transmitting signal according to the inverse value of the sample rate. - View Dependent Claims (12, 13, 14, 15)
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16. A frequency synchronizing method for an on-channel repeater receiving signals on one channel and distributing the signals on the same channel, comprising the steps of:
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a) compensating a carrier frequency error of a receiving signal; b) compensating a sampling timing error of the receiving signal; c) reflecting the carrier frequency error extracted in the step (a) to a transmitting signal; and d) reflecting the sampling timing error extracted in the step (b) to the transmitting signal; and wherein the step a) includes the step of; a1) detecting a carrier phase error in the receiving signal and converting the carrier phase error into a frequency value, and the step c) includes the steps of; c2) inverting the sign of the frequency value; and c3) shifting a carrier frequency of the transmitting signal as much as the sign-inverted frequency value.
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17. A frequency synchronizing method for an on-channel repeater receiving signals on one channel and distributing the signals on the same channel, comprising the steps of:
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a) converting an analog receiving signal into a digital signal; b) compensating a carrier frequency error of the digital signal; c) compensating a sampling timing error of the digital signal; d) reflecting the carrier frequency error extracted in the step b) to a transmitting signal; and e) converting the transmitting signal reflected with the carrier frequency error into an analog signal, wherein the sampling timing error detected in the step c) is equally used in the steps a) and e). - View Dependent Claims (18, 19, 20)
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Specification