Loop antennas are great if you’re stuck in an apartment building or a congested city. They’re easy enough to make, whether you want a portable loop or a permanent installation.

This paper presents a novel model of the inductive coupling using loop antennas and occuring in HF-RFID or NFC systems. It takes into account the coupling coefficient, the chip/antenna matching and ...

A general theory of thin-wire multiturn loop antennas is presented. For convenience the windings of the loop are considered to form a circular helix. An integral equation is derived and solved ...

His design is based on Coaxial Collinear Antenna for ADS-B Receiver by [Dusan Balara] which uses pieces of the coaxial cable cut to the right length.