Generating quasi-random sequences in AMI code

摘要

In order to test coding rule infraction test units for AMI code which are employed for surveillance of digital transmission circuits, an arrangement is provided which generates quasi-random sequences in the AMI code without employing a spur line short-circuited at its end. Previously, no coding rule infractions could be mixed into the generated signals with such a spur line usually employed for generating signals in the AMI code. With the disclosed arrangement a generator for binary quasi-random sequences is provided to whose output one input of a differential amplifier arrangement is directly connected. Another input of the differential amplifier arrangement is connected via a series connection of an exclusive OR element and a time-delay element. Noise pulses which lead to coding rule infractions in the generated output signals can be mixed in via the other input of the exclusive OR element.