Compact printed square meander loop antenna for a Bluetooth headset

The two wireless systems that have experienced the most rapid evolution and wide popularity are the standards developed by IEEE for wireless local area networks (WLANs), identified as IEEE 802.11, and the Bluetooth technology. This paper presents the design and analysis of a printed square meander loop antenna applicable for a Bluetooth headset. The design starts with a half-wavelength square loop operating at 2.45 GHz. Then, the loop was meandered to form sets of square meander loops having reduced area. Investigations were performed through simulations using electromagnetic simulation software, Sonnet Suite. Mathematical computations were made using MathCAD software. Meandering a half-wave length square loop with dimensions of 15 mm × 15 mm results in reduction in the effective area of the loop antenna by 46%. It was found that this has also increased the first resonance of the antenna from 2.04 GHz to 2.45 GHz. To obtain a matched input return loss at the desired frequency of 2.45 GHz, a small rectangular single patch of 1 mm length and 2 mm width has been added adjacent to the feedpoint of the λ/2 meandered loop.