The present inventors produced transgenic silkworms which comprise a promoter of a DNA encoding a protein specifically expressed in the silk gland and a DNA encoding a recombinant antibody whose expression is regulated directly or indirectly by the promoter, and which secrete the recombinant antibody into the silk gland. Each location pad includes multiple radiator coils and driving circuitry configured to select, responsively to the data signals, different respective driving frequencies for the coils and to generate, using the electrical power from the bus, driving signals to drive the coils to produce magnetic fields at the respective driving frequencies. The apparatus comprises a control device adapted to control said switch determining the on period and the off period of the switch to maintain constant the output current to supply said LED diodes. For instance, the plurality of Mobile Nodes may be statically or dynamically assigned the same Home Address.