Design of Wideband Micro strip Band pass Filter for Ultra Low Power Wireless Applications

Abstract

Nowadays, RF Energy harvesting plays an important role in scavenging energy from the ambient sources. The RF energy harvester consist of antenna and filter to improve the performance of the output voltage. The RF circuit also receives the interference signal which reduces the overall performance of the circuit. To reduce the ripples and harmonics at the output voltage of the RF energy harvester a filter is needed. This paper presents a wideband 5th order Chebyshev Band Pass Filter (BPF) for the frequency range of (0.58-3 GHz) is integrated with the RF circuits. The microstrip parallel coupled BPF is designed at a centre frequency of 1.65GHz and 0.5dB pass band ripple. The dielectric material used for designing the BPF is FR4 substrate with a relative permittivity of Er=4.4. This paper also includes a, Coplanar Wave guide (CPW) antenna which has been designed and fabricated for the same frequency range which covers the frequency bands of GSM900, GSM1800, 3G and WiFi. The designed BPF is integrated with the CPW antenna at RF front end of energy harvesting circuits. The advantage of BPF is to reduce the losses and to enhance the overall performance of the output voltage of the RF energy harvester. The harvested energy is used for powering the ultralow power wireless applications