Alarm system for use over satellite broadband
US9131040B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 2009 |
| Grant date | Sep 8, 2015 |
| Priority date | — |
| Expiry date | Sep 20, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M2242/04
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention allows an alarm monitoring to use satellite broadband services as a data link for communication between an alarms system and a monitoring station, middleware provider, individual user, or other alarm monitor. Standard alarm system protocols are modified to make the communication protocol compatible with the features of satellite broadband. These modifications compensate for the time delay in data transmission inherent in satellite communications, as well as other limitations of satellite communications. In particular, the “handshake” tone, instead of “1400 hz for 100 ms, silence for 100 ms, 2300 hz for 100 ms”, is changed to “DTMF ‘A’ for at least 100 milliseconds”. In a preferred embodiment the receiver transmits the DTMF A tone for 250 milliseconds. In addition, the delay for “wait for the Acknowledge tone” is extended from 1.25 seconds, to 5 seconds. The “acknowledge” tone, instead of “1400 hz for 400 ms”, is changed to “DTMF ‘D’ for at least 100 milliseconds”. In a preferred embodiment, the receiver transmits the DTMF D tone for 250 milliseconds.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.