Reduced Amount of Conductive Ink with Gridded Printed Antennas

It becomes more and more common to print tag antennas using electrically conductive ink for mass-produced Radio Frequency IDentification (RFID) tags. Electrical properties of the ink are mostly determined by conductive (e.g. silver) particles mixed into the ink solution. Since silver is relatively expensive it is desirable to minimize the amount of ink used per antenna. This paper illustrates how the printed conductor area of the antenna can be reduced by applying a grid pattern to an existing antenna geometry and to what extent the gridding can be performed without significantly degrading of the antenna electrical properties. Two common antenna structures are used as an example. It is also shown that by slightly modifying the original antenna geometry it is possible to even further reduce the amount of used ink.