US Patent 7259726 Compact loop antenna for inductive read/write apparatus

In order to provide a compact loop antenna, for use in an inductive read/write apparatus, capable of extending a communication range even if the antenna area or power supply thereto is constrained, a compact loop antenna, for use in an inductive read/write apparatus, comprises two layers of loop antennas, each thereof comprising a printed circuit board 2 for featuring a loop pattern 1, a loop pattern 1 formed by an etching process on the printed circuit board 2, and a start terminal 3 and a end terminal 4 for supplying power for signal transmission and outputting a received signal and each thereof maintaining a predetermined distance from each other.