A deep fading assessment of the modernized L2C and L5 signals for low-latitude regions

• Autor(a) principal: Salles, Lucas A.
• Data de Publicação: 2021
• Outros Autores: Moraes, Alison, Vani, Bruno, Sousasantos, Jonas, Affonso, Bruno J., Monico, João F Galera [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1007/s10291-021-01157-4; http://hdl.handle.net/11449/221881

When plasma instabilities arise in the post-sunset time, the so-called ionospheric plasma bubbles may develop, causing amplitude fades and phase oscillations, decreasing the availability and quality of transionospheric communication systems. In the regions where these bubbles appear, deep signal fading may occasionally reach the lowest levels and with loss of signal received for a certain period. In this work, a characterization of deep power fades is performed supported by a dataset covering 5 months of high-rate monitoring data collected at four different locations in Brazil in distinct S4 scenarios for the three available frequencies. Two aspects of the deep fading events were evaluated, the deepest fading attained per minute and the fading events deeper than −15 dB. The inter-frequency analysis showed that as S4 increases, the number of −15 dB fading occurrences increases for all bands and stations. The average number of occurrences reached approximately 7 and 9 cases per minute, respectively, for Presidente Prudente and São José dos Campos. Statistical analysis for fading events deeper than −15 dB obtained probabilities of 1.61%, 2.87% and 3.97%, respectively, for L1, L2C and L5 at Presidente Prudente. Regarding the value of the deepest fading event per minute, the larger difference between L1, L2C and L5 exhibits values around −11 dB at Presidente Prudente. For this station, the average deepest fading values achieved in L2C and L5 bands were nearly twice that of the L1. The results regarding the probability of a deepest fading less than −20 dB per minute for L5 signal present a probability of 1.38% in Fortaleza, while for Presidente Prudente and São José dos Campos, these values were 5.62% and 3.34%.