| 摘要 |
PROBLEM TO BE SOLVED: To provide an antenna booster unit for a terrestrial digital television, which can sharply improve the receiving quality of weak radiowave broadcasting by solidly setting the saturation output, gain and noise index of a high-frequency amplification element to be used for an amplification part to suitable values while quantitatively considering a control factor of receiving quality C/N.SOLUTION: An input matching circuit 3 is inserted in series into the input side of the amplification part 2 to form a booster input terminal, wherein a circuit constant is adjusted so that a noise index level obtained on a booster output terminal is ≤2.0 dB and amplification gain is 15 to 25 dB. Under a medium strong electric field digital broadcast-receiving environment in which analog UHF television broadcasting in a UHF band including a broadcasting frequency band is in a stop state and the entire power of antenna receiving output is -28 dBm and more by the reception of a terrestrial digital television-broadcasting channel group, the receiving quality C/N of weak electric field digital broadcasting included in the broadcasting frequency band and having a receiving level of 28 to 35 dBuV is secured so as to become ≥21 dB. |
