This paper gives the design of Yagi-Uda antenna using microstrip circuit. Microstip circuits are used to implement Yagi-Uda antenna so as to reduce the size but here we have shown only two optimization technique. This has been done by varying the length, width and spacing between reflector, driven element and directors. Simulations are conducted to show how return loss and other parameters vary by varying the above mentioned Yagi-Uda parameters. This antenna is operating very near to resonant frequency fr = 2.4 GHz with the specification relative permittivity ε r = 3.2, height of substrate h=1.6mm, characteristic impedance Z 0 = 50 ohm and thickness of strip conductor t=35um. In this paper, two most approximate results after all these perturbations are analyzed and simulations showing return loss and other parameters like directivity, gain and power radiated are discussed. The simulation process has been done using Advanced Design System (ADS) tool.

The MIMO based CO-OFDM FSO communication system is emerging as a promising approach to meet the future bandwidth requirements for seamless communication. The atmosphere being the propagation medium is a major hindrance in wide-scale acceptability of FSO technology. For seamless and error-free transmission and reception of data, a novel concept of MIMO integrated with RS code is proposed in this paper. The system performance of an RS 64 (RS (255,127)) coded MIMO-based CO-OFDM FSO communication link was investigated using BPSK, QPSK and 16-QAM under the combined effects of geometric losses, path losses and atmospheric attenuations at a hitherto un-investigated data rate of 40 Gbps and a link distance of 5 km. The modified gamma-gamma distribution was used for modeling a moderately turbulent channel. With link length varying over a range of 1 to 5 km, error correction was maximum in 16-QAM as compared to BPSK and QPSK, with 150 to 167 corrected errors. In terms of PAPR, PSK was more apt than QAM, but with a compromise in BER. The geometric losses were reduced with link length due to an increase in error correction capability for all three modulation cases, with the least losses occurring in 16-QAM. At the target bit error rate (BER), the signal to noise ratio (SNR) required for BPSK and QPSK was higher by 3.98 dB and 6.14 dB compared to 16-QAM.

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INTRODUCTION: Covid 19 infection is caused by SARS-COVID virus and responsible for pandemic in 2020. Most common signs and symptoms include fever, cough, lower respiratory tract infection etc. CASE REPORT: A 51 year old male patient, a known case of diabetes, hypertension and chronic renal disease with renal transplant 3 years back and on immunosuppressive drugs was complaining of high degree fever, myalgia, fatigue, abdominal pain, more over the left upper abdomen. USG shows Hypoechoic collection in the inferior pole of spleen measuring 5x6cm with mild perisplenic collection, suggestive of splenic abscess. The patient had undergone emergency laparotomy of splenectomy. On histopathology, refractile, aseptate, broad angle fungal hyphae suggestive of Mucormycosis. PAS stain was Positive. DISCUSSION: Spleen is a rare site for fungal infection. With superadded COVID 19 infection and bilateral basal consolidation in the lungs, the underlying splenic lesion will be confused as part of thromboembolic episodes rather than fungal infection. Hence, delay in treatment of antifungal drugs will lead to mortality in such cases. CONCLUSION: In COVID 19 infections, the rare manifestation of fungal infection to be considered while treating the immunosuppressive patients.