Investigation on path loss for 5g wireless communication in an indoor environment.

Abstract

Large scale path loss modeling is critical in both mobile and fixed broadcasting system design. Predicting a system's radio coverage area is not standardized. As a result, before installing a wireless system, the channel surroundings, frequency range, as well as preferred radio coverage range must all be considered. Path loss estimation is critical in link characterization and predicting cell coverage in mobile radio systems. Increased subscriber numbers, particularly in urban areas, necessitate the addition of more base stations as well as channels. To achieve highest effectiveness from the spectrum sharing concept in contemporary communication network, interference at cell boundaries must be completely removed. An accurate path loss prediction method is used to properly determine the cell size. Beginning with signal propagation physical processes and basic path loss models, this thesis aims to demonstrate various precise path loss prediction models that can be utilized for fifth generation (5G) wireless indoors networks. For a thorough analysis, the single frequency close in (CI) references free space and floating intercept (FI) path loss models are used for continuous radio wave propagation in an enclosed corridor. This study analyses the large-scale path loss models for an indoor corridor environment at frequencies of 28 and 38 GHz. The measurement environment consists of an indoor corridor with both line-of-sight (LOS) and non-line of sight (NLOS) scenarios using vertical–vertical (V–V) and vertical–horizontal (V–H) antenna polarizations. The single-frequency CI, FI, free space large-scale path loss models and measured data from the measurement campaign were used to evaluate the performance analysis. It also focuses on various parameters, such as standard deviation, path loss exponent (PLE), accuracy, simplicity, and stability of the models. The FI and CI models produce comparable results for both antenna polarizations and clearly fit with the measured path loss. The PLE, with the highest value of 3.33 at 38 GHz (V–H), is much higher in the NLOS scenario with V–H polarization due to the signal degradation along the path from the transmitter (Tx) to the receiver (Rx). This is because there is no direct LOS between the Tx and Rx antennas. The Rx only relies on signal diffractions and reflections from obstacles as it transmits through the path from the Tx antenna. Furthermore, this research evaluates the third order CI PLM as well as the improved version of the wellknown CI and FI path loss models at frequency bands of 28 and 38 GHz in the same measurement environment. One of the key findings is that the improved versions of these models typically perform better in terms of consistency than the standard models thereby justifying their high accuracy level. The third order CI PLM and the improved versions of the CI as well as the FI demonstrate a significant improvement for various antenna polarizations. The mean prediction error (MPE) and standard deviation error (SDE) also show how precisely and accurately the improved models predict the path loss. Additionally, the improved models provide the reasonable responsiveness and uniformity of the parameters with the change in the antenna polarization and lower the shadow fading's standard deviation in LOS as well as NLOS situations. The results confirm that the modified versions of CI and FI models predict path loss better in an enclosed environment for 5G networks. In addition, the analysis of a path loss prediction model based on squared root distance (SRD) measurement for wireless services in enclosed spaces was also performed in this work. The CI free space reference distance model as well as the FI model is employed to evaluate and assess this model. This research also contains an improved CI as well as FI method to assess the consistency of the squared root distance model utilizing two main error benchmarks: MPE and SDE. The main results indicate that the squared root distance model, which perfectly aligns the measurement data, offers good precision for predictions in the two bandwidths studied. Besides that, when contrasted with the conventional CI and FI models, the squared root distance path loss models have outstanding mean prediction error and standard deviation error. Ultimately, this analysis showed that the standard deviation of shadow fading can be substantially lowered in LOS as well as NLOS, suggesting greater accuracy in estimating path loss. Having seen the need to achieve a further improvement in the performance of the existing CI model, this study proposed an improved CI model which was evaluated at frequencies of 28 and 38 GHz. It outperforms the conventional CI model. The research results indicate that the proposed enhance model delivers a better output when compared to the existing single frequency path loss model characteristics of the enclosed environment used. The findings also indicate that the upgraded model raises stability and sensitivity in the NLOS scenarios (which usually has high level of signal degradation), indicating a higher degree of path loss prediction accuracy. The path loss measurements and model analysis presented here will be useful in designing 5G wireless communication systems for indoor environments, particularly for power budget calculations. These path loss models were improved by changing existing parameters, resulting in considerable improvements for various antenna polarizations, particularly in the path loss exponent and shadow fading standard deviation. Understanding that these two parameters are critical for minimizing path loss in wireless communication systems. The Rohde and Schwarz SMB 100A radio signal generator, a Rohde and Schwarz FSIQ 40 signal analyzer, two broadband horn antennas, and MATLAB software were used for measurement and model analysis.