Skywave adaptable communication apparatus
US4937822A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1989 |
| Grant date | Jun 26, 1990 |
| Priority date | — |
| Expiry date | Jun 27, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B7/18532
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An adaptive TDMA (time division multiple access) communication system is illustrated which dynamically maintains potentially different frequencies between nodes of the communication system using a process of communicating the quality of received signals between the nodes and storing this information so that an optimum frequency band can be selected whereby whenever signal quality deteriorates, an alternate frequency can be selected to provide continued communications. An embodiment of the system spans both high frequency (HF) and very high frequency (VHF) to establish the communications through atmospheric induced refractions (reflections) beyond line of sight between directly communicating nodes of the system. Further, the system uses frequency hopping both for signal transmission security and for node identification. When a node is traffic idle and also on a periodic maintenance basis, frequency bands other than the traffic frequency are analyzed for potential future use.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.