Authors : Jagannath Jena; Biswajit Munda; Narendra Kumar Nahak; Ajay Singh

Volume/Issue : Volume 11 - 2026, Issue 4 - April

Google Scholar : https://tinyurl.com/4u4z5cpc

Scribd : https://tinyurl.com/mpu8hs8d

DOI : https://doi.org/10.38124/ijisrt/26apr2233

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Abstract : This work presents a systematic analysis of gain and noise behavior in cascaded communication systems using the Friis formulation. A modular simulation framework is developed in Python to evaluate total gain and noise figure across multi-stage configurations. The model considers variable stage count, realistic gain and noise distributions, and strict linear– logarithmic unit consistency. Parametric analysis is performed by varying first-stage gain and noise figure over a wide operating range. Results indicate strong dominance of the first stage, where increased front-end gain suppresses the contribution of subsequent noisy stages. A saturation trend is observed beyond a threshold gain region, where further improvement in total noise figure becomes marginal. A Monte Carlo simulation with more than 1000 iterations is conducted to examine statistical variability under practical uncertainties in gain and noise parameters. The obtained mean noise figure of 3.17 dB with a standard deviation of 1.16 dB highlights significant sensitivity of cascaded systems to early-stage variations. An optimization study is carried out to identify the first-stage gain minimizing overall noise figure, yielding an optimal value near 27.88 dB with a minimum achievable noise figure of 1.15 dB under unconstrained conditions. The analysis confirms that system noise performance asymptotically approaches the first-stage noise limit. The proposed framework provides reproducible evaluation, comparative visualization, and statistical insight suitable for RF front-end design studies. The results emphasize the critical role of front-end design and establish a basis for further constrained and multi-objective optimization in practical communication systems.

Keywords : Cascaded Systems; Friis Formula; Noise Figure; RF Front-End; First-Stage Dominance; Monte Carlo Simulation; Gain Optimization; Statistical Variability; Sensitivity Analysis; Communication Systems.

References :

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