Public address system and method for an urban transit vehicle

• US 20040240679A1
• Filed: 06/30/2004
• Published: 12/02/2004
• Est. Priority Date: 03/07/2000
• Status: Abandoned Application

• Current Assignee: DRI (S&P Global Inc.)
• Original Assignee: DRI (S&P Global Inc.)
• Inventors: Halberstadt, Steven B., Kennedy, James D., Rowlette, John R. Jr.
• Application Number:
  US10/880,811
• Publication Number:
  US 20040240679A1
• Time in Patent Office: Days
• US Class Current: 381/82
• CPC Class Codes: H04R 27/00 Public address systems circuits for preventing acoustic reaction H04R3/02; circuits for distributing signals to loudspeakers H04R3/12; monitoring or testing arrangements for public address systems H04R29/007; amplifiers H03F

Abstract

Apparatus and method for allowing an operator of a transit vehicle to make public address announcements to passengers internal and external to the vehicle. The safety of the vehicle and passengers is maintained through providing a hands-free directional microphone having noise canceling characteristics. The microphone is used as an input device for receiving an audio signal and provides the signal to a processing module that converts the signal into a digital signal. The digital signal is than processed by a digital signal processor to cancel undesirable noise common to a transit vehicle. The noiseless signal can then be converted into an analog signal and recorded within the memory of the public address system where, upon needed, the signal can be transferred to an output device such as a speaker system internal or external to the vehicle. After playback, the recorded message can also be easily repeated by means of a repeat-switch.

Claims

1. A public address system for an urban transit vehicle of the type including:

a passenger receiving interior space;

an operator'"'"'s station located within the interior space;

a steering column within the operator'"'"'s station;

and

a cowl around at least a portion of the steering column;

the improvement comprising;

a noise-cancelling, directional microphone mounted on the cowl of the steering column for collecting audio signals and for converting the audio signals to electrical signals;

an audio processor mounted in a secure housing non-accessibly located out of the operator'"'"'s station for receiving electrical signals from the microphone, for processing the electrical signals to remove noise therefrom, for recording the electrical signals, and for playing back the electrical signals following the recordal thereof to prevent feedback;

a foot switch located within the operator'"'"'s station;

the audio processor being responsive to a first activation of the foot switch to cause recording of signals received through the microphone and responsive to a second activation of the foot switch to start playback of the recorded signals;

an amplifier for receiving electrical signals from said audio processor and for converting the electrical signals to amplified electrical signals;

speakers for receiving amplified electrical signals from the amplifier, for converting the amplified electrical signals to audio signals and for broadcasting the audio signals at least within the passenger receiving interior of the urban transit vehicle.