A device network to process signals has target devices, selecting devices that
are movable relative to the target devices, and controllers. The controllers are
in communication with the target devices and the selecting devices. Each of the
selecting devices has a position sensor and an orientation sensor to provide spatial
and angular co-ordinates of position and orientation when pointing to a target
device and upon receiving a user input. Each of the selecting devices also has
a signal processor to generate a control signal having the position and orientation
data. This control signal is then transmitted by a transmitter, via a radio frequency
channel, to a controller. Upon receiving the control signal, the controller determines
whether, for example, a target device has been selected by a selecting device by
comparison of the orientation data with a derived orientation based on the position
data and the known position of the target devices.
