Digital data signal conversion technique - includes double detection process in production of inverse non-return-to-zero code

摘要

The digital data conversion technique includes a detection of the signal in order to find out whether the value of all the even bits of the digital signal is equal to a digital zero. A second detection of the signal is carried out in order to find out whether the value of pairs of these detected even bits is a digital zero, and also whether a bit preceding an odd-bit has a direct current component. A detector signal is formed from the result of the second detection. The digital data signal is then converted into an inverse non-return-to-zero code (INRZ) using this detector signal. The technique also includes division of the digital signal into a series of n-bit words, the detections being effected to determine the number of odd bits, whose value is a digital zero, contained in each of the series of words.