Micro-Strip Patch Antenna (MSPA) finds large scale applications in various fields of communication. Elliptical shaped patch antenna is a prominent category among MSPAs. Possibility of circular polarization and dual resonant frequencies makes the Elliptical Micro-strip Patch Antenna (EMPA) widely accepted in modern communication devices. The present work aims to identify the constraints in further advancements in the design of EMPA and propose a novel shape to overcome these constraints. Minimizing the patch area and increasing the number of degrees of freedom in design were found to be the challenges. To overcome these challenges, a newly shaped patch called ‘DoubleElliptical Patch (DEP)’ is proposed for designing ‘DoubleElliptical Micro-strip Patch Antenna (DEMPA)’. A double-ellipse is a combination of two half-ellipses either with the same minor axis and different semi-major axes or with the same major axis and different semi-minor axes. The DEP has an additional degree of freedom in design compared to elliptical patch, which leads to greater design flexibility. In the present work, a DEP with the same horizontal major axis and centrally given feed was designed using Ansoft HFSS software. The semi-minor axis of upper halfellipse was varied by keeping the semi-minor axis of lower halfellipse a constant. The radiation properties of DEMPA were found to be similar to that of corresponding EMPA and this was achieved with less patch area. The maximum percentage reduction in patch area was 10.714%. The DEMPA covered the entire frequency range of Ultra Wide Band (UWB).

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Double Elliptical Micro-strip Patch Antenna (DEMPA) is developed out of Double Elliptical Patch (DEP) which is a recently proposed shape of patch. The use of DEP results in higher flexibility in design of patch antenna and thus promotes antenna miniaturisation. The present work is an attempt to demonstrate the miniaturisation of radiolocation antenna through the concept of Design Flexibility (DF). In this paper, optimised neural network model for synthesis of DEMPA has been developed for radiolocation applications for which the earmarked frequency band is 8.50 GHz – 10.50 GHz. With the help of synthesis model, for an arbitrary operational frequency of 9.85 GHz, radiolocation antennas with effective patch area ranging from 142 mm2 to 66 mm2 were designed by using DEPs. In this case, the percentage reduction in effective patch area was found to be 53.52%. It shows that double elliptical patches can be employed to develop miniaturised radiolocation antennas. One prototype antenna was fabricated and tested to demonstrate the efficacy of the methodology adopted. The fabricated antenna had resonance at 10.15 GHz with a reflection coefficient of -20.73dB and bandwidth of 3.106 GHz (from 7.458 GHz to 10.564 GHz). Its Fractional Bandwidth was 34.469%. Positive and reasonably good gain was maintained over the entire working band. At resonance, the peak gain was 4.22 dB.The measured characteristics of antenna were in close agreement with the simulated results. The methodology presented in this paper can also be applied to frequency bands for other wireless applications.