초록 ▼

A frequency counter is disclosed which determines the frequency of an input signal in a high speed and accurate manner. High speed is achieved by utilizing electronic digital processing circuitry. The high degree of accuracy is achieved by a combination of elements which perform period averaging of

A frequency counter is disclosed which determines the frequency of an input signal in a high speed and accurate manner. High speed is achieved by utilizing electronic digital processing circuitry. The high degree of accuracy is achieved by a combination of elements which perform period averaging of an integral number of periods of the input signal over a flexible measurement interval. The counter is particularly useful in accurately measuring low frequency signals.

대표청구항 ▼

Apparatus for determining the frequency of an input signal by measuring an integral number of cycles of said input signals over a flexible measurement interval comprising: (a) input means, iNcluding first generating means, for receiving said input signal and for generating a series of trigger pulses

Apparatus for determining the frequency of an input signal by measuring an integral number of cycles of said input signals over a flexible measurement interval comprising: (a) input means, iNcluding first generating means, for receiving said input signal and for generating a series of trigger pulses wherein each trigger pulse is representative of the start of a cycle of said input signal; (b) clock means for providing an elapsed time signal representative of the duration of said flexible interval; (c) logic means, connected to said input means, for providing a cycle count signal representative of the number of integral cycles of said input signal occurring during said flexible interval, wherein said cycle count signal is a function of the number of trigger pulses in said series; and (d) processing means, including second generating means, connected to said clock means and to said logic means, for computing the frequency of said input signal as a function of said cycle count signal and said elapsed time signal and for generating a frequency measurement signal indicative of the computed frequency.