Study Of Generalized Shrinking Sequence

The pseudorandom sequences have wide applications in the practice, so the design of sequence generators is always the central task. In this thesis, we propose a new design for sequence based on shrinking generator-the generalized shrinking sequences, and the pseudo-randomness of the generalized shrinking sequences are investigated. Simultaneously, some results on generalized self-shrinking sequences are introduced.The main results are as follows:1. In chapter two, a new q-ary generalized self-shrinking sequence is introduced. The sequences generated have good pseudo-randomness. Simultaneouly two parameters are chosen as the section key to strengthen the cryptosystem.2. In chapter three, the results show that, on condition that the clock-controlled sequence is m sequences, the generalized shrinking sequences have large period and linear complexity, good correlation property, and the generalized shrinking sequences family has rich algebra structure. On the other hand, on condition that the clock-controlled sequence is generalized self-shrinking sequences, the sequences generated have good A;-error linear complexity.3. The q-ary generalized shrinking sequence is discussed in chapter four. The sequences have good pseudorandomness as binary ones.Just as q-ary generalized self-shrinking sequences, two parameters are chosen as the section key to strengthen the cryptosystem.