The optical fiber coupling apparatus for coupling light from a light-emitting device into an optical fiber in an optoelectronic package comprises a microactuator for positioning the end of the fiber with respect to the light-emitting device, and a control circuit in which the manipulated variable is a position of the fiber end. The method can generally comprise communicating indirectly between a first base station and a wireless communication device using a first repeater and a first RF backhaul link. During the transport, the locking element runs laterally along a fixed device that constantly narrows the transport distance in the direction of transport. And a third chamber in the post treatment section contains a third treatment medium through which the water to be treated flows during treatment.