Disclosed is a multiplex communication system which comprises a master unit, and a plurality of slave units, wherein the master unit and the plurality of slave units are annularly connected by a signal line. The master unit transmits a request signal to each of the slave units via the signal line and...http://www.google.com/patents/US7546192?utm_source=gb-gplus-sharePatent US7546192 - Multiplex communication system and car-passenger protection system using the same
