Digital broadcast receiving apparatus and receiving method
First Claim
1. An apparatus for receiving a digital broadcast signal that is available to receive a digital satellite broadcast signal via an antenna comprising:
- a detecting circuit configured to orthogonally detect a received signal sent from the antenna to a baseband signal;
a carrier/noise (C/N)-value-calculating circuit configured to measure an average value of amplitude in a radial direction of signal points of phase mapping of the baseband signal obtained by the detecting circuit to calculate a carrier/noise ratio for the received signal;
a phase-noise-amount-calculating circuit configured to measure an average value of amplitude in a circumferential direction of signal points of the phase mapping of the baseband signal to calculate an amount of phase noise of the received signal;
a bit-error-rate-measuring circuit configured to measure a bit-error rate of transport stream that is given by demodulating the baseband signal;
a determining circuit configured to determine a factor in deterioration for receiving characteristics of the antenna based on results of the C/N-value-calculating circuit, the phase-noise-amount-calculating circuit, and the bit-error-rate-measuring circuit; and
a measure-mode-setting circuit configured to set a desired measure mode based on the determination result of the determining circuit.
1 Assignment
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Accused Products
Abstract
A factor in deterioration of receiving characteristics of an antenna is automatically determined and automatically improved. In an apparatus for receiving digital broadcast signal, when receiving the signal, a received signal sent from the antenna 1 is orthogonally detected to a baseband signal; an average value of amplitude in radial direction of signal points of phase mapping of the baseband signal is then measured to calculate a C/N value for the received signal; an average value of amplitude in circumferential direction of signal points of the phase mapping of the baseband signal is measured to calculate an amount of phase noise of the received signal; a bit-error rate of transport stream that is given by demodulating the baseband signal is then measured; a factor in deterioration for receiving characteristics of the antenna is determined based on these results; and a desired measure mode is set based on the determination result thereof.
29 Citations
7 Claims
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1. An apparatus for receiving a digital broadcast signal that is available to receive a digital satellite broadcast signal via an antenna comprising:
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a detecting circuit configured to orthogonally detect a received signal sent from the antenna to a baseband signal; a carrier/noise (C/N)-value-calculating circuit configured to measure an average value of amplitude in a radial direction of signal points of phase mapping of the baseband signal obtained by the detecting circuit to calculate a carrier/noise ratio for the received signal; a phase-noise-amount-calculating circuit configured to measure an average value of amplitude in a circumferential direction of signal points of the phase mapping of the baseband signal to calculate an amount of phase noise of the received signal; a bit-error-rate-measuring circuit configured to measure a bit-error rate of transport stream that is given by demodulating the baseband signal; a determining circuit configured to determine a factor in deterioration for receiving characteristics of the antenna based on results of the C/N-value-calculating circuit, the phase-noise-amount-calculating circuit, and the bit-error-rate-measuring circuit; and a measure-mode-setting circuit configured to set a desired measure mode based on the determination result of the determining circuit. - View Dependent Claims (2, 4, 5, 6, 7)
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3. A method for receiving a signal in an apparatus for receiving a digital broadcast signal that is available to receive a digital satellite broadcast signal via an antenna, the method comprising:
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orthogonally detecting a received signal sent from the antenna to a baseband signal; measuring an average value of amplitude in a radial direction of signal points of phase mapping of the baseband signal obtained in the orthogonally detecting to calculate a carrier/noise ratio for the received signal; measuring an average value of amplitude in a circumferential direction of signal points of the phase mapping of the baseband signal to calculate an amount of phase noise of the received signal; measuring a bit-error rate of transport stream that is given by demodulating the baseband signal; determining a factor in deterioration for receiving characteristics of the antenna based on results of the measuring an average value of amplitude in a radial direction, measuring an average value of amplitude in a circumferential direction, and measuring a bit error rate; and setting a desired measure mode based on the determination result of the determining.
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Specification