| 摘要 |
PROBLEM TO BE SOLVED: To suppress noise generated when changing the gain of an amplifier stepwise.SOLUTION: The receiving apparatus is provided with an RF section which amplifies RF signals and outputs the amplified signals, a mixer which converts the output from the RF section into signals in a lower band, a signal processing section which filters the converted signals, a demodulator which demodulates the filtered signals, level detectors which compare the level of any one of the signals obtained from the input to the RF section to the output from the signal processing section with a threshold value, and which output the result as comparison signals, a gain controller which generates gain control signals corresponding to the comparison signals, a gate signal generator, and an interpolator. The receiving apparatus is so configured as to stepwise change the gains from the input to the RF section to the output from the signal processing section according to the gain control signals, the gate signal generator generates gate signals in synchronization with the gain change, and the interpolator holds or interpolates the output from the demodulator in a period indicated by the gate signals. |
