Patent · US Expired

Utility monitor communications systems

US5381462A · kind A · utility

117Cited by
11References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 29, 1992
Grant dateJan 10, 1995
Priority date
Expiry dateMay 29, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M11/002
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.