In the framework of Near-field (NF) UHF-RFID applications, a large number of ad-hoc antennas have been proposed in the last decade. In particular, the authors recently proposed novel reconfigurable antenna configurations, the so-called Modular Antennas. In these layouts, a travelling wave antenna is combined with a low-gain resonating antenna, which share the surface of the desktop reader antenna. Specifically, a spiral Travelling Wave Antenna (TWA) is used to generate a strong and uniform field in proximity of the antenna surface. Then, such a microstrip transmission line is used to feed the resonating antenna in order to extend the reading range up to few decimeters. Also, to make the antenna almost scalable, several antenna solutions have been proposed, so spreading the generated field in a large and arbitrarily shaped area.