Browse Prior Art Database

DYNAMIC ENVIRONMENTAL ADAPTING MODULATION INDICATOR SCHEME FOR OPTIMIZED AUDIO OPERATION

IP.com Disclosure Number: IPCOM000007742D
Original Publication Date: 1996-Aug-01
Included in the Prior Art Database: 2002-Apr-18
Document File: 2 page(s) / 107K

Publishing Venue

Motorola

Related People

Joseph PatiƱo: AUTHOR [+3]

Abstract

Due to the large number of people using 2-way radio communications devices, there is a large vari- ation in the audio levels and other parameters (such as inflection and mouth-to-microphone distance) which influence the perceived audio quality. It is highly desirable to obtain uniform audio levels and quality from each and every user.

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Technical Developments

DYNAMIC ENVIRONMENTAL ADAPTING MODULATION INDICATOR

SCHEME FOR OPTIMIZED AUDIO OPERATION

by Joseph Patifio, Terry K. Mansfield and Mark G. Spiotta

  Due to the large number of people using 2-way radio communications devices, there is a large vari- ation in the audio levels and other parameters (such as inflection and mouth-to-microphone distance) which influence the perceived audio quality. It is highly desirable to obtain uniform audio levels and quality from each and every user.

  The primary means for unifying audio levels is through manual training ofthe subscriber unit users in the recommended operation of the radio equip- ment. Unfortunately, this approach applies one set of standards as well as guidelines to a group of peo- ple, each of whom may have different needs, voice levels, and inflections.

  Another approach uses an automatic level con- trol in the console equipment. This approach helps provide a uniform volume level to the dispatcher, which is particularly critical to dispatchers who use headphones, but does not impact the voice quality in the subscriber-to-subscriber loop (via either talk- around or a repeater). However, the root cause of the problem is not addressed: Getting the user to provide an optimum voice level into the subscriber radio's microphone. Until this occurs, we will con- tinue to degrade the audio quality by providing sub- optimal levels to the voice coding algorithms. In addition, in analog systems, the deviation level will either be too high (clipped for extra-loud voices) or too low, which degrades audio quality.

  Refer to attached Block Diagram 1 and FIow- chart. This invention is a method ofproviding a real- time audio quality feedback indication to the user showing the radio's microphone modulation that allows the user to adjust their voice level and mouth distance to the microphone accordingly on a real time basis.

  This is accomplished by using two microphone ports. One port is used to capture the user's envi- ronment and the other port is used to capture the actual user voice. The mic...