Criptografia física por embaralhamento espectral aplicada a sinais com taxas de transmissão distintas

• Autor(a) principal: Nogueira, Marcelo Pereira
• Data de Publicação: 2022
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/217250
• topic: Criptografia; Segurança de sistemas; Telecomunicações

The transmission ratio and the number of internet users have increased considerably in communications systems. The concern about security and secrecy of data generated, transmitted and stored has become a import characteristic for the development and technologies evolution. The investigation, development and evaluation of new improvements for encryption techniques were realized in this work. The techniques investigated were spectral phase encoding and spectral shuffled in digital signal processing (SPE-SS-DSP) with implemention of the dynamic key (DK) applied the signals with distinct transmission rates and with different signalings. The news improvements applications for encryption techniques were evaluated from two encrypted signals transmitted over channel with additive white Gaussian noise (AWGN). The development of these news applications were performed by computer simulations. The Matlab ® was software used to implement in algorithm the encryption techniques, dynamic key, news improvements applications, noise channel and the results obtained. The signal quality evaluation metric and new improvements applications for encryption techniques was the penalty of the signal-to-noise ratio (SNR) for given value of bit error ratio (BER). The encrypted signals showed BER values above forward error correction (FEC) threshold and the new applications didn’t generate penalties for the transmitted and recovered signals. The signals encrypted with dynamic key, application of distinct transmission rates and with different signalings compared to signals without encryption and improvements showed pratically the same results based on BER and SNR values. The techniques developed, after being evaluated, showed good efficiency and feasibility of studies and applications in optical and mobile networks.