Patent ID: 7561212
Filing Date: 2009-07-14
Classification: H04L,H04N

Abstract:
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.