| 摘要 |
PURPOSE:To change the periodicity of the maximum periodic system, and to prevent the deterioration of a randomization due to the periodicity by controlling the feedback tap of a maximum periodic system generating circuit, and changing the length of the maximum periodic system. CONSTITUTION:A system length deciding circuit 1 is constituted of the maximum period generating circuit, and the output code is inputted to a control circuit 2. The control circuit 2 outputs a control signal for switching the disconnection of the feedback tap of a variable length maximum periodic system generating circuit 3. The variable length maximum periodic system generating circuit 3 selects the feedback tap according to the control signal outputted from the control circuit 2, changes the number of steps of a delay element, and generates the maximum periodic system. A monitoring circuit 4 monitors the output system of the variable length maximum periodic system generating circuit 3, and requests the output of the next code to the system length deciding circuit 1 at the time of the end of the system. |
