Siren detector

  • US 5,710,555 A
  • Filed: 05/17/1996
  • Issued: 01/20/1998
  • Est. Priority Date: 03/01/1994
  • Status: Expired due to Term
First Claim
Patent Images

1. A siren detector for detecting siren sounds which precess at known rates within a selected frequency band to facilitate preemptable control of traffic light signals to enable an emergency vehicle to pass through a traffic intersection on a priority basis, said detector comprising transducer means for detecting said sounds and for producing an electrical sound output signal representative thereof, first filter means for filtering said sound output signal to produce an antialiased output signal to prevent aliasing in a subsequent analog to digital conversion process, and second filter means for producing a band-limited signal by filtering said antialiased output signal to reject signals outside said selected frequency band;

  • and limiter-discriminator means for producing an indication of the frequency of said band-limited signal.

View all claims

    Thank you for your feedback