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A thorough millimeter-wave measurement campaign is carried out in an indoor environment with an aim at characterizing the short-term fading channel behavior. The measurements are conducted in a variety of scenarios, with frequencies ranging from 55 GHz to 65 GHz, in line-of-sight and nonline-of-sight conditions, and combinations of horizontal and vertical polarizations at both transmitter and receiver. A number of fading models are tested, namely Rayleigh, Rice, Nakagami-m, α-µ, κ-µ, η-µ, and α-η-κ-µ. The statistics under analysis are those characterizing the fading amplitude and the frequency selectivity. In particular, the probability density and cumulative distribution functions for the former and level crossing rate per bandwidth unit for the latter are the respective first-and second-order statistics used. To this end, from the experimental data, the parameters of the models are estimated and the corresponding theoretical curves are plotted and compared with the empirical ones. Whereas the required theoretical formulations of the first-order statistics of these models are already well known, those of the second-order statistics as well as these fitting process in such a band shown here are unprecedented in the literature.

Recent standardization of portions of the millimeter-wave (mm-wave) band for fifthgeneration (5G) operation has called for further research on how short-term fading behaves in that unexplored part of the spectrum. With such a target, this paper reports on a thorough measurement campaign conducted in an indoor environment characterized by rich-multipath scattering, a part of a modern building, with floor and ceiling constructed of reinforced concrete over steel plates with wood and plasterboardpaneled walls. Particularly, measurements have been performed in a variety of scenarios, under line-ofsight (LoS) and non-line-of-sight (nLoS) conditions, for a wide range of frequencies, namely from 25 to 40 GHz -a span of 15 GHz -therefore, including 26, 28 and 39 GHz. First and second order statistics of representative fading models, namely Rayleigh, Rice, Nakagami, folded normal, α-µ, η-µ, κ-µ, and α-η-κ-µ have been investigated. The metrics used in the analysis were the normalized mean square error (NMSE), the Kolmogorov-Smirnov (KS), and the Akaike information criterion (AIC). Additionally, the study of the κ-µ model is advanced, in which new, exact, simple closed-form expressions for probability density function, cumulative distribution function, and level crossing rate are derived for some particular cases, namely for µ = n + 1/2 in which n ∈ N.

Resumo-Maior conectividade e interatividade são os anseios da próxima geração de transmissão digital da indústria de radiodifusão. Além disso, com a redução do espectro das emissoras de TV, concedido para as operadoras celulares, se torna necessário o uso eficiente do espectro na faixa de UHF e uma nova padronização se faz necessária. O ATSCé o padrão de TV utilizado em vários países há mais de 20 anos, dada suas limitações, um novo padrão foi proposto para suprir a necessidade de uma maior interação entre emissoras e usuários, com maior conectividade, qualidade deáudio, vídeo em alta resolução e uma maior flexibilidade para atender usuários fixos e móveis. Vistos estes novos desafios, neste trabalho, a camada física do ATSC 3.0 para o sistema de transmissãoé simulada utilizando o ambiente de simulação MATLAB R , com objetivo de explorar a funcionalidade de cada bloco proposto, assim como servir de referência para implementação e posterior validação do sistema em hardware. Com o intuito de aferir a plataforma de simulação desenvolvida, a mesma foi validada de acordo com vetores de teste compatíveis com a norma existente, fornecidos por um modulador comercial padrão, garantindo a interoperabilidade do sistema.