Patent ID: 8068801

Claim:
An electric wave receiving apparatus that receives an electric wave including a time code, comprising: an antenna that receives an electric wave; a first amplifier that amplifies a signal received by the antenna; a plurality of filter circuits that extract signals in different frequency bands respectively from an output of the first amplifier; a plurality of detector circuits that demodulate time codes respectively from outputs of the respective filter circuits correspondingly to the plurality of filter circuits; a plurality of automatic gain control circuits that respectively generate gain control signals indicating average signal levels of output signals of the detector circuits correspondingly to the plurality of detector circuits; a first selector that selects one gain control signal indicating a maximum signal level among the plurality of gain control signals output from the plurality of automatic gain control circuits; and an arithmetic processing section to be able to analyze the time codes by inputting outputs of the plurality of detector circuits, wherein the one gain control signal selected by the first selector is supplied to the first amplifier in order to control an amplification factor of the first amplifier so that signal levels output from the plurality of detector circuits do not become excessive, and the arithmetic processing section selects an output to enable the analysis of the time code among the respective outputs of the plurality of detector circuits to perform the analysis of the time code from the output.