Abstract
This paper demonstrates the design, fabrication and characterisation of a dual-frequency antenna array for wireless sensor networks (WSNs). The proposed design is a dual-band coaxial-fed 2 x 2 array rectangular U-Slot microstrip-patch antenna. It works on frequency bands of 2.1 GHz and 3.5 GHz. The targeted applications are the future high-speed WSNs based communication standards utilising MIMO to increase data-rates and that operate in 1-5 GHz frequency range. The initial design and simulation is performed in ADS Momentum using Rogers TMM3 substrate (epsilon(r) = 3.27 and h = 6.35 mm). Later, this substrate is replaced by RT/Duroid 5880 because of the rare availability of the former. Good measured results are achieved in terms of return-loss and bandwidth. The maximum obtained gain for 2 x 2 U-slot rectangular patch antenna array is 11 dBi. Substrate losses are also taken into account during simulation. Simple design procedure and optimisation techniques are also discussed to design a single element dual-band patch antenna.