Design, Analysis and Characterisation of Spoof Surface Plasmon Polaritons based Wideband Bandpass Filter at Microwave Frequency

This paper presents the wideband bandpass filter (BPF) in the microwave frequency domain. The realisation approach is based on spoof surface plasmon polaritons (SSPPs) phenomenon using plasmonic metamaterial. A novel unit cell is designed for filter design using an LC resonator concept. Then SSPPs BPF is realised using an optimised mode converter and five unit cells. This paper includes a brief design detail of the proposed novel unit cell. The passband of BPF is achieved at approximately 1.20 - 5.80 GHz, 3dB bandwidth is tentatively 4.60 GHz and the insertion loss is less than 2 dB approximately over the passband. The overall dimension of fabricated filter is (90 x 45) mm. A basic schematic of transmission line representation is also proposed to evaluate the BPF structure

A Compact Reconfigurable Multi-mode Resonator-based Multi-band Band Pass Filter for Intelligent Transportation Systems Applications

A compact wide band reconfigurable bandpass filter (BPF) which utilises a hemi-circular flower shaped multimode resonator (MMR) is presented. The proposed MMR provides three resonant modes which fall within the broad frequency spectra. Among these, two modes are even and one is odd. These modes are optimised by varying the dimensions so as to obtain the desired frequency response. The fractional bandwidth is more than 96 per cent. The filter can be operated as multi-band BPF. In OFF condition of ‘Pin’ diode, the centre frequencies are 2.43 GHz, 3.5 GHz, and 5.9 GHz in ON condition of ‘Pin’ diode centre frequencies are 2.43 GHz, 3.5 GHz, 5.9 GHz, 6.5 GHz, and 8.8 GHz which are used for vehicular, WiMAX, intelligent transportation systems and satellite communication respectively. Microstrip filter structures are integrated with ‘Pin’ diodes. Appropriate biasing has been provided by choosing lumped components with precise values. The insertion loss in OFF condition are 0.5 dB, 0.67 dB, and 0.8 dB and in ON condition 0.5 dB, 0.7 dB, 1.2 dB, and 1.9 dB. The measured results agree well with the full-wave simulated results

Design of RF Receiver Front end Subsystems with Low Noise Amplifier and Active Mixer for Intelligent Transportation Systems Application

This paper presents the design, simulation, and characterization of a novel low-noise amplifier (LNA) and active mixer for intelligent transportation system applications. A low noise amplifier is the key component of RF receiver systems. Design, simulation, and characterization of LNA have been performed to obtain the optimum value of noise figure, gain and reflection coefficient. Proposed LNA achieves measured voltage gains of ~18 dB, reflection coefficients of -20 dB, and noise figures of ~2 dB at 5.9 GHz, respectively. The active mixer is a better choice for a modern receiver system over a passive mixer. Key sight advanced design system in conjunction with the electromagnetic simulation tool, has been to obtain the optimal conversion gain and noise figure of the active mixer. The lower and upper resonant frequencies of mixer have been obtained at 2.45 GHz and 5.25 GHz, respectively. The measured conversion gains at lower and upper frequencies are 12 dB and 10.2 dB, respectively. The measured noise figures at lower and upper frequencies are 5.8 dB and 6.5 dB, respectively. The measured mixer interception point at lower and upper frequencies are 3.9 dBm and 4.2 dBm

Harmonic suppressed coupled stepped-impedance resonator based dual-band tunable bandpass filter

In this paper, a tunable dual-band bandpass filter (BPF) based on a varactor-loaded coupled stepped-impedance resonator is presented. Transmission matrices techniques are employed to explain the working concept of proposed tunable BPF. For validating the proposed concept, a hardware prototype is fabricated and characterized. As per the measured results, when the center frequency of the lower band is tuning from 2.15 to 2.40 GHz, the upper band is fixed at 4.5 GHz; and when the center frequency of the upper band is tuning from 4.5 to 4.75 GHz, the lower passband almost remains constant at 2.25 GHz. Proposed tunable filter is capable of working at higher passband frequencies. Spurious harmonic suppression up to 15 GHz is demonstrated. Center frequency of dual-passband is tunable using only two dc control voltages