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Overview of Mobile Channels and Equalizers
Published in K. C. Raveendranathan, Neuro-Fuzzy Equalizers for Mobile Cellular Channels, 2017
The most widely used path loss model for signal strength prediction and simulation in macrocellular environments is the Hata–Okumura model (Okumura 1968, Hata 1980). This model is valid for the 500–1500 MHz frequency range, receiver distances greater than 1 km from the base station, and base station antenna heights greater than 30 m. There exists an elaboration on the Hata–Okumura model that extends the frequency range up to 2000 MHz. It was found that these models are not suitable for lower base station antenna heights, and hilly or moderate-to-heavy wooded terrain. However, other subcategories and different terrain types can be found around the world.
Maritime cognitive radio spectrum sensing based on multi-antenna cyclostationary feature detection
Published in International Journal of Electronics, 2020
Jingbo Zhang, Feng Ran, Da Liu
Considering the effects of refraction, scattering and reflection paths in the maritime radio transmission environment, the literature (Mo, Chen, & Shen, 2012) modified the parameters of the Longley-Rice model (Longley & Rice) (also known as the irregular terrain model (ITM) model) and applied it to the maritime radio communication. At the same time, the paper also pointed out that other classical terrestrial channel models (such as the Okumura model (Okumura, Ohmori, & Kawano et al., 1968), the Hata model (Hata, 1980), the Lee model (LeeWC, 1985, etc.) also need to be modified to be applicable to maritime wireless communications. Considering the impact of maritime climate (e.g. fog, rain attenuation, etc.), the improved ITM model is proposed in (Zhao, Chi, & Ren, 2014). This model improves the accuracy of ocean channel transmission loss prediction, therefore, this model is also used as the channel model of this paper.