Systems and methods for detecting a gunshot

A method for accurately determining the occurrence of a gunshot comprising:

• a) capturing an audio signal, either digital or analog, with such fidelity that the constituent frequencies that comprise ultrasonic frequencies are retained and preserved;
• b) utilizing at least one bandpass filter to capture one or more discrete samples within a range from 48 kHz to 384 kHz;
• and
• c) determining whether said one or more discrete samples are consistent with a short-duration, high-energy, wide-spectrum, ultrasonic burst that corresponds to an ultrasonic signature of a gunshot.

A detection device for determining the occurrence of a gunshot comprising:

• a) a microphone that is capable of capturing acoustic frequencies within the ultrasonic spectrum, above 48 kHz, for capturing an audio signal;
• b) an analog to digital converter for converting the microphone's analog audio signal to a digital audio signal;
• c) a processing circuit for processing and analyzing the resulting digital audio signal;
• and
• d) a data storage device for retaining and preserving any captured or analyzed data wherein:
• said microphone and analog to digital converter capture a digital audio signal with such fidelity that the constituent frequencies that comprise the ultrasonic spectrum are retained and preserved;
• said processing circuit samples the captured digital audio signal for frequency information in a range from 48 kHz to 384 kHz;
• said processing circuit mathematically transforms the frequency information by creating a spectrogram having a spectrum of frequencies of the signal as it varies with time or a spectrum of frequencies over a short period of time;
• said processing circuit determines whether said spectrogram or spectrum or sampled portions of the spectrogram or spectrum contain a short-duration, high-energy, wide-spectrum, ultrasonic burst, that corresponds to a known ultrasonic signature of a gunshot;
• and
• said storage device retains and preserves the data as it is captured, transformed and used for determination.

A detection device for determining the occurrence of a gunshot comprising:

• a) a microphone capable of capturing acoustic frequencies within the ultrasonic spectrum, above 48 kHz, for capturing an audio signal;
• b) an analog to digital converter for converting the microphone's analog audio signal to a digital audio signal or at least one filtering circuit;
• c) a processing circuit for processing and analyzing the resulting digital audio signal;
• d) a data storage device for retaining and preserving any captured or analyzed data wherein:
• the microphone and analog to digital converter capture a digital audio signal with such fidelity that the constituent frequencies that comprise the ultrasonic spectrum are retained and preserved;
• the processing circuit mathematically applies, or the at least one filtering circuit applies, a bandpass filter(s) to capture discrete sample(s) within a range from 48 kHz to 384 kHz;
• the processing circuit determines whether the discrete sample(s) are consistent with the characteristic short-duration, high-energy, wide-spectrum, ultrasonic burst, that corresponds to the known ultrasonic signature of a gunshot;
• and
• said storage device is for retaining and preserving the data as it is captured, transformed and used for determination.