This work describes a sensor array based on optical
emitters, which allows io detect obstacles in railways.
The sensorial system consists of a barrier of emitters and
another of receivers, placed at opposite sides of the
railway. Apart from the disposition of the sensorial
I system, it is necessary a codification method for the
emission in order to detect the reception or the nonreception
of transmissions between an emitter and a
receiver. The method is based on a signal codification
using complementary sequence pairs, suitably adapted for
their simultaneous emission through the transmission
channel. A high reliability under adverse conditions is
achieved with the developed system, being possible to
. detect the presence of obstacles, and to inform about their
situation.
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