Abstract: A device for the transmission of electromagnetic signals, the device comprising: a conductive element at least one inducer, for inducing charge in said conductive element; a transmission circuit, for generation and transmission of electromagnetic signals; wherein said conductive element and said at least one inducer are movable, with respect to each other, between a plurality of relative positions; in a first position of said relative positions, said at least one inducer is arranged to induce a charge in said conductive element; in a second position of said relative positions, said conductive element is arranged to discharge; the conductive element is arranged to couple with the transmission circuit, in said first position and/or said second position, such that charging and/or discharging of said conductive element causes the transmission circuit to generate and transmit an electromagnetic signal; and the device is arranged such that movement of said device causes relative movement of said conductive element

Abstract: An object detector comprising: a transmitter arranged to generate a transmit signal; a transmit loop antenna, coupled to said transmitter and arranged to radiate said transmit signal; and a receive loop antenna arranged to generate a receive signal from received radio waves; wherein said received radio waves include said radiated transmit signal and, in the presence of objects within range of the device which reradiate said transmit signal, one or more radio waves reradiated by such objects; said receive signal includes a component corresponding to said transmit signal and, in the presence of reradiated radio waves, one or more components corresponding to said reradiated radio waves; and said object detector further comprises a signal detector, coupled to said receive loop antenna and said transmitter, the signal detector arranged to detect changes in the amplitude and/or phase of said receive signal which are due to changes in said components corresponding to said reradiated radio waves.

Abstract: A device for the transmission of electromagnetic signals, the device comprising: a conductive element at least one inducer, for inducing charge in said conductive element; a transmission circuit, for generation and transmission of electromagnetic signals; wherein said conductive element and said at least one inducer are movable, with respect to each other, between a plurality of relative positions; in a first position of said relative positions, said at least one inducer is arranged to induce a charge in said conductive element; in a second position of said relative positions, said conductive element is arranged to discharge; the conductive element is arranged to couple with the transmission circuit, in said first position and/or said second position, such that charging and/or discharging of said conductive element causes the transmission circuit to generate and transmit an electromagnetic signal; and the device is arranged such that movement of said device causes relative movement of said conductive element

Abstract: An RFID tag includes a plastic container having at least one particle that is disposed therein and that is formed from metal or metal coated and/or fabricated from a plurality of different metals. A receiver unit detects RF pulses which are generated by the Triboelectric effect of the particles.