Filtro rejeita-faixa para uso em decodificadores de sinais de tv aberta na banda C para mitigar interferências de sinais do 5G

Abstract

Since the 5G spectrums were auctioned in Brazil for the use of mobile telephony, ANATEL has been looking for ways to resolve the interference that will affect the transmission of signals transmitted in band C. This problem is caused due to one of the spectrums that will be used for telephony mobile, in the frequency range of 3.3 to 3.7 GHz, which will cause interference in the initial frequencies used for downlink in open TV signals, which operates in the C band, in the frequency range of 3.4 to 4.2 GHz With this situation in question, a possible solution is to reject the 5G operating band, in band C, avoiding LNB saturation. Therefore, a narrowband band-reject filter is a possible solution. This work aimed to develop two microstrip band-reject filters using a Defected Ground Structure (DGS) configuration based on Matrioska geometry, with the function of mitigating 5G signal interference. The filters were designed to have a rejection band in the frequency range of 3.3 to 3.7 GHz, which is the operating band of fifth-generation mobile phone systems. The product of this work was developed through studies on band-reject filters, where we analyzed the S21 parameter using LiteVNA. In addition, parametric, analytical and computational analyzes were carried out using software, such as HFSS and Matlab, for the design and creation of prototypes, verification of operation and efficiency. The filters, in addition to solving the standard problem, could also be the subject of future research studies. Furthermore, they can be used in other systems in which their functionality may be suitable.