US 4,786,168 A · Frequency domain laser velocimeter signal processor

Abstract

A laser velocimeter signal processor for measuring the signal frequency within a signal burst. The input signal is converted to digital by an ADC 16 and then shifted into shift registers 30 and 31. An automatic gain circuit 15 controls the gain of the input signal. A signal integration circuit 32 determines when a signal burst has been captured by the shift registers and and then transfers the contents of the registers to data latches 33 and 34. The data in data latches 33 and 34 is processed by digital bandpass filters 57-63, square law detectors 64-70, burst counters 71-77 and signal processor 78 to determine the frequency of the signal within the captured signal burst.

Claims27

Dependent claims

A method of processing a succession of random output burst signals from a laser velocimeter to measure an oscillation frequency within each of said random output burst signals comprising the steps of:

converting at a sequence of times with short time intervals each of said random output burst signals from said laser velocimeter to a number L of parallel digital bits forming a pulse train representing the amplitudes of each of said random output burst signals at each of said respective sequences of time;
serially storing a number of bits M from each of said pulse trains of L parallel digital bits;
detecting and sensing from the number of M bits entering said storage when a random output burst signal is contained within storage;
transferring out of storage the said number of M stored bits when a random output signal is detected within storage;
and
processing the transferred number of M bits to measure the oscillation frequency within each of said detected random output burst signals prior to processing a next succeeding random output burst signal.

3 more elements

Apparatus for processing a succession of random output burst signals from a laser velocimeter and measuring the oscillation frequency within each of said random output burst signals comprising:

analog-to-digital converter means for receiving and converting at a sequence of times with short time intervals each of said random output burst signals from said laser velocimeter to a number L of parallel digital bits representing the amplitudes of each of said random output burst signals at each of said time sequences;
a number L of Mx1 digital shift register means for storing a number M of each of said L parallel bits;
means, under the control of the bits entering and leaving said shift register means for detecting when a random output burst signal is contained within said shift registers and for transferring out of the shift registers the said M bits stored therein whenever a random output signal burst is detected;
and
means for processing the transferred M bits to measure the oscillation frequency within said detected random output burst signal prior to receiving the next of said succession of random output burst signals.

2 more elements

Dependencies are inferred from the claim text.

Frequency domain laser velocimeter signal processor

Life of this patent

Frequency domain laser velocimeter signal processor

Life of this patent

Abstract

Claims27