Abstract: A communication system, such as an identification system for use in animal feeding or milking parlors, has a driver (16; 200; 320; 350), which supplies current to an antenna (for example 1; 68; 208; 306; 352). That current causes the antenna to emit power (in the from of a time varying magnetic or electromagnetic field), which energizes a transponder (220) operable to transmit an identification signal (such as an RF signal). The driver and antenna are connected to a parallel inductor, which reduces the total inductance of the load seen by the driver. The antenna may be one of a plurality of antennae, all of which are connected to the same driver. Each antenna is located in a respective stall in a milking or feeding parlors so that the system can identify which animal is in which stall of the parlors at a given time.