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Key research themes
1. How can empirical and measurement-driven models improve path loss predictions in diverse terrestrial environments?
Accurate path loss prediction is vital for designing and optimizing wireless communication networks, influencing coverage, capacity, and quality of service. Empirical models, derived from extensive field measurements, provide practical and computationally efficient tools for long-range path loss estimation across diverse environments such as urban, suburban, and industrial settings. However, their accuracy can vary with terrain, frequency, and local factors, driving research to collect large-scale measurement data and refine these models with advanced regression and spatial interpolation techniques.
Key finding: This paper presents an extensive measurement campaign covering 145.5 km in Nigerian urban environments across multiple VHF and UHF frequencies, filtering out small-scale fading to isolate shadowing effects. It demonstrates... Read more
Key finding: The study offers a comprehensive overview of well-known empirical models (e.g., Okumura-Hata, COST 231-Hata, SUI) utilized for path loss prediction below 11 GHz, emphasizing their dependence on environmental parameters. It... Read more
Key finding: The literature review synthesizes empirical, deterministic, and stochastic propagation models specific to wireless sensor networks in vegetation-rich agricultural environments. It underscores the importance of accounting for... Read more
Key finding: Through empirical LTE network measurements in urban environments at 2.5 GHz, this study compares multiple classical propagation models (Friis, SUI, Okumura, Ericsson, COST-231 Hata), finding that the COST-231 Hata model... Read more
Key finding: Focused on a suburban environment in Dehradun, India, this paper conducts drive test measurements using TEMS tools to collect radio frequency data representative of vegetated and built clutter. It assesses statistical and... Read more
2. What are the effects of atmospheric and environmental factors on radio wave propagation at high frequencies, particularly for 5G and mmWave bands?
High-frequency bands, including mmWave and sub-THz frequencies, face unique propagation challenges due to atmospheric absorption, weather phenomena, and environmental conditions such as temperature, humidity, rain, and vegetation. Understanding and modeling these effects on path loss and signal strength is critical for the deployment and optimization of upcoming cellular communication technologies like 5G and beyond. Research integrates empirical observations with simulation models and machine learning to quantify atmospheric influences and provide predictive frameworks for system designers.
Key finding: Utilizing the NYUSIM mm-wave channel simulator and multiple regression techniques, this work investigates the combined effects of atmospheric parameters—temperature, rain rate, humidity, and pressure—on path loss at... Read more
Key finding: This comprehensive dataset, collected over 2012-2021 in NYC, provides empirical path loss and channel characteristic models for mmWave and sub-THz bands (up to 142 GHz). It reveals frequency-dependent sparsity and multipath... Read more
Key finding: Conducting controlled high-mobility channel measurements at 2.55 and 25.5 GHz, this study provides a direct comparison of delay-Doppler characteristics for sub-6 GHz and mmWave bands using identical transmitter/receiver... Read more
Key finding: Through field measurements in southern Nigeria across GSM and 4G bands, this research quantifies the correlation between atmospheric refractivity—characterized by temperature, pressure, and humidity variations—and received... Read more
3. How do complex environments such as industrial facilities and underground mines affect radio propagation characteristics and what modeling approaches are effective?
Radio propagation in harsh or confined physical environments like factories, refineries, and underground mines faces unique challenges including severe multipath, shadowing, and scattering due to metallic structures, rough surfaces, and geometry constraints. Understanding channel impulse responses, delay spreads, fading statistics, and path loss exponents through site-specific measurement campaigns facilitates the development of suitable channel models. These efforts enable reliable wireless control and communication solutions tailored for industrial automation, safety, and sensor networks in such environments.
Key finding: Using spread spectrum correlation sounders at 2.4 and 5 GHz, this study conducts detailed RF propagation measurements in diverse industrial sites including automotive factories and machine shops. Analysis of path loss, delay... Read more
Key finding: Narrowband measurement campaigns in a curved underground mine gallery at 2.45 and 18 GHz expose two distinct propagation regimes separated by gallery curvature, with received power attenuation quantified at 10 to 37 dB per... Read more
Key finding: Extensive narrowband and wideband measurements in a Canadian underground gold mine at 2.4 GHz reveal large-scale distance-power path loss exponents and delay spread parameters derived from frequency channel sounding. The... Read more
Key finding: Measurements conducted at an oil refinery demonstrate severe multipath and frequency-selective fading for broadband digitally modulated signals in a dense metallic outdoor industrial setting. Received power and waveform data... Read more