Method and apparatus for transmitting monitor data
US5659303A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 20, 1995 |
| Grant date | Aug 19, 1997 |
| Priority date | — |
| Expiry date | Apr 20, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08C17/02
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for transmitting data from a monitoring station using frequency hopping and interval hopping as described. The output frequency of a transmitter in the monitoring station is hopped between selected output frequencies by retrieving random numbers from a table, generating a control voltage corresponding to the retrieved random number, applying the control voltage to an RF oscillator and transmitting a signal from a transmitter in the monitoring station using the signal from the RF oscillator as a carrier. The output frequency of the transmitter is limited between a maximum output frequency and a minimum output frequency by comparing the retrieved random number to data limits stored in a memory in the transmitter and rejecting retrieved random numbers outside of the retrieved limits. Interval hopping is realized by selecting a random number from the random number table, multiplying the random number by a fixed increment and adding the product to a minimum time interval.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.