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A modified slotted microstrip patch sensor antenna has been developed for sensitivity enhancement to measure the moisture content of leaves. The design incorporates a rectangular slot positioned above the feed of a rectangular patch antenna. The antenna achieves resonant frequency at a lower range than the operating frequency of a traditional patch antenna without slot while maintaining a miniaturized form factor. To evaluate the sensitivity of the proposed modified slotted patch antenna, the variation in the resonant frequency and the reflection coefficient (S11) is observed with the sample under test (SUT), i.e., leaf is placed above the patch. A comparative analysis with regard to sensitivity and shift in frequency is performed between the designed antenna structures. The designed antenna is fabricated on a 0.8 mm F4B substrate in order to resonate within the 2.40–2.80 GHz range under unloaded conditions. The antenna's sensitivity is tested by performing parametric analysis with respect to the permittivity of the leaf ranging from 20 to 30. The experimental results reveal that the sensitivity of the proposed patch antenna is enhanced by a factor of 1.67 as compared to traditional patch antenna for the four levels of SUT, demonstrating an enhanced sensitivity in detecting the moisture content of leaves. [ABSTRACT FROM AUTHOR]

Channel estimation (CE) plays a crucial role in establishing a wireless link, specifically at the receiver node. Most of the receivers that estimate the channel is in the presence of AWGN. However, these schemes perform expressively worse when the impulsive noise is added in AWGN which is introduced by manmade sources (pressure cooker, motorbike, electric supply) as well as natural noises (earthquakes and thundering). The major contribution of this research is to analyze the channel estimation schemes in the Gaussian mixture model (GMM) environment. The performance of channel estimation schemes has been compared in terms of mean square error (MSE) and bit error rate (BER). Four channel estimation schemes e.g., MMSE, DFT, correlation- based methods like Gauss-Seidel (GS) and Successive Over-Relaxation (SOR), are studied and analyzed. The study reveals that the correlation scheme based on the method of SOR is more effective as compared to the methods of DFT, MMSE and GS because of faster convergence rate along with the minimum number of iteration. SOR shows sustainable results up to the probability of an impulsive element of 5 Percent. [ABSTRACT FROM AUTHOR]