Method for synchronizing a wide area network without global synchronizing
US5130987A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 11, 1991 |
| Grant date | Jul 14, 1992 |
| Priority date | — |
| Expiry date | Sep 11, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J3/0676
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A frequency-hopping packet communication system without a master clock or master control unit is based on use of a receiver's frequency hopping timing and identification to control communication. A frequency-hopping band plan, involving the number of channels and the pseudo-random pattern of frequency change and nominal timing of changes, is universally known to each node in the network. A transmitter acquires synchronization with a target node by use of information previously received from or about a target indicating timing of present idle frequency hop of the target receiver. Each receiving node establishes in each station or node a table of receiver frequency hopping sequence offsets (hop timing offsets) of each other node within its communication range, and each node announces its presence on each frequency in a packet with a hop timing offset indicator. The hop timing offset indicator is a key used to read a table to allow nodes to set themselves in synchronization with one another. A location indicator built into the address of each packet is used to randomize an ordered frequency-hopping table at each node. Frequency-hopping is implemented by the division of communicaton sl…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.