The invention concerns the use of a material based on organic andor inorganic fibres and chitosan for fixing metal ions contained in an effluent. A transmitter mixes an information-carrying signal and a non-modulated wave signal with a carrier signal, thereby producing a first and second radio frequency signals for radio wave transmission. The present invention contemplates wire bonding and encapsulation of individual die as well as multiple die on a single wafer. A fully integrated RF switch is described including control logic and a negative voltage generator with the RF switch elements.