Patent ID: 7555029

Claim:
A decoding method for receiving a plurality of standard radio waves respectively having signal configurations in accordance with respective specifications which define carrier channels and formats and for decoding time code signals carried by said standard radio waves, comprising: a bit synchronizing step of extracting at least part of a bit waveform common to said specifications as an extracted signal from a waveform of each of said time code signals given by each of said carrier channels, and of synchronizing each of said time code signals in terms of bit sequence in accordance with said extracted signal; a channel selection step of determining an evaluation index indicating a good or bad reception condition for each of said carrier channels from said bit waveform, and of selecting a single channel from said carrier channels in accordance with said evaluation index; a specification discrimination step of extracting a bit waveform corresponding to a characteristic code, which differs in each of said specifications, from the time code signal of said selected channel, and of determining a discriminated specification of the time code signal given by said channel in accordance with contents of said characteristic code; and a decoding step of decoding said time code signal to time data in accordance with the format of said discriminated specification; wherein said bit synchronizing step is a step of extracting as said extracted signal an edge part of an added value waveform which is given by convolution-adding in every given bit period for sampling data obtained by sampling said time code signal in a sampling period smaller than said given bit period.