Wire and Cable

Two types of wire are used to build a low frequency RFID antenna. One is the antenna iteslf and the other is the cable between the reader and the anenna.

Antenna are made from many turns of fine wire. The loops generate a magnetic field to charge the tag. The ideal strand thickness is approximately 26 AWG (0.014"/0.36mm diameter).

Rather than wind many turns of fine wire, stranded wire can be used. Low resistance wire is best. Litz wire is the lowest resistance wire. The individual strands are coated with a thin insulator so that they are electrically separated.

Antennas can be placed inside plastic pipe. suspended from cables or attached to wooden frames.

Twinax cable is used to connect the antenna to the reader which can be up to 130 meters apart. Longer lengths of twinax will have more resistance and can lower the antenna voltage. Longer lengths also adds capacitance.

Solid wire can be used for small antennas which require many layers of wraps.