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TV White Space (TVWS) Technology
Published in Prashant Ranjan, Ram Shringar Rao, Krishna Kumar, Pankaj Sharma, Wireless Communication, 2023
Prashant Ranjan, Ram Shringar Rao, Krishna Kumar, Pankaj Sharma
Three tuples are required for the geolocation database to approximate the availability of TVWS within a geographical area. These tuples are the availability of time, location, and frequency. There is a variety of propagation models for different purposes, and their brief comparison is tabulated (Table 3.2), and two popular TVWS propagation models are: Okumura-Hata Model. The Hata models were designed to support the frequency range (150-1500MHz) for Urban cellular planning and are focused on the tower height more than 30m. This model assumes that the transmitter is at more height than the average height of the rooftops [17].Longley-Rice model and the irregular terrain model (ITM). This model is widely used as it is ideal for any RF devices from handheld walkie-talkies in VHF band to microwave links in SHF band. Electromagnetic parameters, terrain, atmospheric diffraction, and ground cluttering are used to calculate the radio signal’s attenuation at any point on the Earth [18].
RF Channel Modeling for 5G Systems
Published in Athanasios G. Kanatas, Konstantina S. Nikita, Panagiotis Mathiopoulos, New Directions in Wireless Communications Systems, 2017
Theofilos Chrysikos, Stavros Kotsopoulos
The original Hata model is distance-bound (1–20 km) and frequency-bound (150–1500 MHz). Various extensions have been suggested, with an original 2 GHz bound [54]. The Hata model was validated for frequencies beyond the 2 GHz in [47].
Hybrid Kriging and multilayer perceptron neural network technique for coverage prediction in cellular networks
Published in International Journal of Parallel, Emergent and Distributed Systems, 2020
Naima Mezhoud, Mourad Oussalah, Abdelouahab Zaatri, Zoheir Hammoudi
In light with standard radio propagation model, e.g. Hata model, Okumura-Hata model [7,8], the knowledge of the characteristics of the base stations (antennas) in the vicinity of the geographical area of interest, where the cellular network experimentation is taking place, is crucial as it enables us to determine the receiving signal strength from the servicing base station. The base station characteristics include location (latitude and longitude of the base station for the ith base station), its power level (Txi), its height and carrier frequency, Cell ID as well as associated environmental factors (e.g. urban versus rural, density of buildings, the width of roads, etc.). The information about the base station characteristics is often provided by the network provider, municipality and/or communication regulator bodies.
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.
Video Delivery Architecture for Hierarchical HetNet: HH-D2D Caching
Published in IETE Technical Review, 2018
Sachin Umrao, Mukesh Kumar Maheshwari, Navrati Saxena, Abhishek Roy
To evaluate the performance of our proposed HH-D2D caching architecture, we use Matlab R2014b and develop the HetNet simulation model. We consider an LTE-A network with 250 users distributed randomly in the circular area of 250 m radius. In our simulation, we have considered Random Walk Mobility Model [21]. In our simulation, the location of an HSD changes randomly. Due to random locations, sometimes when more HSDs meet in one place and participate in auction game, then the MNO can have many options to choose, and in that way, it can select the cheap and the best HSDs for data offloading. This ultimately improves the network performance in terms of bit rate per user and results in reduced delay. We use 20 MHz bandwidth and 64 QAM modulation technique [20]. COST-231 Hata model is used to calculate the path loss for D2D and cellular link [19]. We use 23 and 10 dBm transmit power cellular and D2D communication, respectively. Simulation parameters are tabulated in Table 3.