Short-range magnetic communication system
US5771438A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1997 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | Mar 26, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J7/00034
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A system and method communicate signals between a portable unit and a communications system. The portable device communicates with a base unit using inductive coupling. The base unit is further connected to a wider communication system such as a telephone network. Multiple, orthogonally arranged transducers are used in the base unit to provide a more complete magnetic field and to prevent mutual inductance nulls which are otherwise present in a magnetic field. The use of short-range inductive coupling minimizes the power requirements and limits interference with other sources. The inductive coupling may also be used to recharge a battery in the portable device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.