In many physical experiments, linear frequency modulated (LFM) signals
are widely used to probe objects in different environments, from
outer-space to underwater. These signals allow a significant improvement
in measurement resolution, even when the observation distance is great.
For example, using LFM probe signals in underwater investigations
enables discovery of even small objects covered by bottom sediments.
Recognition of LFM (chirp) signals depends on their compression based on
matched filtering. This work presents two simple solutions to improve
the resolution of the short chirp signals recognition. These methods are
effective only if synchronization between the signal and matched filter
(MF) is obtained. This work describes both the aforementioned methods
and a method of minimizing the effects of the lack of synchronization.
The proposed matched filtering method, with the use of n parallel MFs
and other techniques, allows only one sample to be obtained in the main
lobe and to accurately locate its position in the appropriate sampling
period Ts with accuracy Ts/n. These approaches are appropriate for use
in probe signal processing.