05381462 is referenced by 109 patents and cites 11 patents.

A utility meter reading and communications system gathers data from utility meters and sends that data to a utility company's central data collection point (host computer) via phone lines. The system places a call on the user's telephone line at a specified time and date and transmits data using dual-tone multifrequency (DTMF) format. The system ensures that users still may use the telephone line by sensing off-hook conditions initiated by a resident's telephone and immediately dropping the line to reestablish dial tone for the residential customer. The system uses a variety of error-detection procedures and communications protocols to ensure a high degree of reliability in communicating data to and from the central office and the utility meter system. The system also uses communications protocols and handshaking to ensure accurate data communication and allow immediate interruptions of communications should the customer attempt to use the telephone line.

Title
Utility monitor communications systems
Application Number
7/891298
Publication Number
5381462
Application Date
May 29, 1992
Publication Date
January 10, 1995
Inventor
Donald L Meyer
Long Lake
MN, US
Rodney L Larson
Minnetonka
MN, US
Agent
Schwegman Lundberg and Woessner
Assignee
Datran Systems Corporation
MN, US
IPC
H04M 11/00
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