EAS system employing pseudorandom coding system and method
US6750768B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Sep 4, 2002 |
| Grant date | Jun 15, 2004 |
| Priority date | — |
| Expiry date | Sep 4, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/2488
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
According to the invention, a system and method of reducing noise interference in a way that employs pseudorandom coding. A transmitter and receiver are provided to send and receive a string of non-periodic pulses. The string of non-periodic pulses can be a sequence of pseudorandom codes. The random transmission of pulses in a non-periodic manner promotes a significant immunity to periodic interferences of constant noise operating in a surveillance area. The string of non-periodic pulses can be mutually spaced and binary, in the form of 0 or 1, and can include several bits per cycle to measure the mean and standard deviation of the string of non-periodic pulses received. A circuit is coupled to the transmitter and receiver for comparing the portion of the string of non-periodic pulses received with the string of non-periodic pulses transmitted; and whereby an alarm in triggered if the portion of the string of non-periodic pulses is above a threshold value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.