Reis, AntónioRocha, José Ferreira daGameiro, AtilioCarvalho, José Pacheco de2019-12-032019-12-032019http://hdl.handle.net/10400.6/7655This work presents the coder and decoder of block 3B4B with auxiliary channel. The coder 3B4B converts an input 3 bits word in an output 4 bits word. It transmits an equal number of 1’s and 0’s to provide a DC constant component. It increases the transitions number, improves the system quality and security. The objective is also to improve the system potentialities with an auxiliary channel to monitor the communication (alarm). The main channel is real, but the auxiliary channel is fictitious.engBlock codesDigital systemsTransmission linesconference object