Patent ID: 6646548
Filing Date: 2003-11-11
Classification: G08B

Abstract:
An electronic siren comprising:a command unit for selectively generating at least one command signal; a microprocessor programmed with at least one algorithm; a memory accessible by said microprocessor, said memory containing look up tables defining values used by said algorithm to emulate the frequency range, the rate of frequency change &Dgr;f and amplitudes as a function of frequency for at least a sweep up-down siren sound; a class D amplifier which receives and amplifies a signal generated by said microprocessor; and a speaker operatively connected to said amplifier, wherein said microprocessor executes said algorithm in response to a said command signal and said algorithm utilizes said data to produce a series of digital outputs emulating said siren sound and said digital pattern is converted to an audio signal which is applied to said amplifier.