System and method for detecting seat occupancy in a vehicle

US7298262B2 · kind B2 · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Klaus Hofbeck · Dresden, DE
• Birgit Rosel · Regensburg, DE

Key dates

• Filing date: Nov 18, 2003
• Grant date: Nov 20, 2007
• Expiry date: Feb 20, 2024

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S13/931
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A system for determining seat occupancy in a motor vehicle includes a microwave transmitter, a microwave receiver and preferably a reflector. If a person is between those appliances, the microwave radiation is attenuated. The reflector can be a backscattering device, such that the radiation received by the receiver is unequivocally associated with the reflector. Furthermore or alternatively, the transit time of the microwaves can be measured, to be subsequently processed in combination with an analysis of the seated position of passengers. In preferred embodiments, the microwave radiation diffraction properties around an object are also used to obtain the seated position of passengers. The determination of a seat occupancy and optionally of seat occupancy mode can be advantageously used for locking or on the other hand releasing an airbag.