Method and apparatus for synchronizing a signal to a time base

A method of communicating information indicative of the waveform of a periodic signal across a communications channel comprising the steps of:

• selecting a rate at which said signal is to be sampled;
• sampling said signal at said selected rate;
• and
• transmitting the samples taken of said signal across said communications channel, CHARACTERIZED IN THAT said selecting step comprises the steps of:
• choosing how many samples of said signal are to be taken during a complete period thereof;
• sampling said signal at an arbitrary sampling rate;
• counting the number of samples obtained by sampling at said arbitrary rate;
• comparing the counted number of samples to the chosen number of samples;
• adjusting the arbitrary sampling rate when the counted number of samples differs from the chosen number of samples;
• and
• repeating the sampling, counting, comparing and adjusting steps until the counted number of samples equals the chosen number of samples, whereupon said adjusted arbitrary rate becomes said selected sampling rate.

A method of replicating the waveform of a periodic signal at a site remote from the occurrence thereof so that the replica waveform is synchronized to the signal, comprising the steps of:

• sampling the amplitude of the periodic signal;
• converting each of the amplitudes into a corresponding digital value;
• transmitting the digital values to the remote site across a communications channel;
• converting each of the digital values into an analog voltage having a corresponding magnitude, CHARACTERIZED IN THAT said periodic signal is automatically sampled at a rate selected rate to obtain a predetermined number of samples during the first full period of said signal, said sampling being accomplished by:
• choosing how many samples of said signal are to be taken during the period thereof;
• sampling and signal at an arbitrary rate with such sampling commencing at the beginning of the first full period thereof;
• counting the number of samples obtained by sampling at said arbitrary rate;
• comparing the counted number of samples to the chosen number of samples;
• adjusting the arbitrary sampling rate when the counted number of samples differs from the chosen number of samples;
• and
• repeating the sampling, counting, comparing and adjusting steps, until the counted number of samples equals the chosen number of samples, whereupon said adjusted arbitrary sampling rate becomes the selected sampling rate.

Apparatus for communicating data across a communications channel comprising:

• means for establishing a rate at which such data is to be sampled;
• means for sampling said data at said established rate;
• and
• means for transmitting the samples of said data across said communications channel, CHARACTERIZED IN THAT said sampling rate establishing means includes:
• means for choosing how many samples are to be taken of said data;
• means for sampling said data at an arbitrary rate;
• means for counting the number of samples taken at said arbitrary sampling rate;
• means coupled to said counting means and said choosing means for comparing the counted number of samples to the chosen number of samples;
• and
• means coupled to said comparing means and said sampling means for adjusting the arbitrary sampling rate until the counted number of samples equals the chosen number of samples, whereupon the adjusted arbitrary sampling rate becomes the established sampling rate.