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Dynamic Selection of Telephone System Bandwidth Based on User's Subjective Reactions

IP.com Disclosure Number: IPCOM000050884D
Original Publication Date: 1982-Dec-01
Included in the Prior Art Database: 2005-Feb-10
Document File: 2 page(s) / 62K

Publishing Venue

IBM

Related People

Broockman, EC: AUTHOR

Abstract

This article describes a technique for selecting the bandwidth signals transmitted to a telephone user as a function of that user's physiological response to the perceived quality of received signals. At the beginning of each telephone conversation, maximum bandwidth is employed. If the user's physiological reaction (speaking volume, earpiece pressure, handset pressure) indicates that he is completely satisfied with the quality of the signal, a different coding algorithm is employed to reduce the bandwidth used for signals sent to the user's telephone. The bandwidth may be periodically increased or decreased in the course of a telephone conversation depending upon the user's reactions.

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Dynamic Selection of Telephone System Bandwidth Based on User's Subjective Reactions

This article describes a technique for selecting the bandwidth signals transmitted to a telephone user as a function of that user's physiological response to the perceived quality of received signals. At the beginning of each telephone conversation, maximum bandwidth is employed. If the user's physiological reaction (speaking volume, earpiece pressure, handset pressure) indicates that he is completely satisfied with the quality of the signal, a different coding algorithm is employed to reduce the bandwidth used for signals sent to the user's telephone. The bandwidth may be periodically increased or decreased in the course of a telephone conversation depending upon the user's reactions.

Signal bandwidth is related to user's perceived quality of received telephone signals. Type T1 and T4 telephone networks are designed with a 64k bps bandwidth for each voice channel. Some network users may be entirely satisfied with signals at a lower bandwidth, e.g., 48k bps or 32k bps. If a user is dissatisfied with the quality of signals, however, that dissatisfaction manifests itself in several subtle and often unconscious user reactions. The user may grip the handset more tightly or press the earpiece to his ear. He may also talk louder. These physiological reactions can be used to select the lowest bandwidth which will provide signals of acceptable perceived quality to the user.

Fig. 1 is a three-dimensional graph relating earpiece pressure (ep), and handset pressure (hp) and user speaking volume (v) to the bandwidth employed in sending signals to a reacting user. If earpiece pressure, handset pressure and volume are...