Chaos-based Pseudo-random Sequence Generation And Its Implementation

Chaos is a ubiquitous nature phenomenon. The solution of chaos mathematical model is an extremely instable movement localized on finite space. As for instability, that is, the adjacent orbit will separate exponentially with the time goes by. For such reason, the long-term behavior of system exhibit chaos and the time & space average of system shows typically randomness. So the signal generated by iteration of simple chaos mathematical model get the feature of randomness and owns the statistical characteristics similar to white noise. The sensitivity to the initial value of chaos system makes it easy to produce a lot of sequences, which can be the source of the digital noise.The chaotic phenomenon is the foreland and hot topic in both theory study and project application. Up to now, the theory researches about chaotic phenomenon are mature. There are many chaotic models that produce the chaotic sequences, such as Logistic map, Tent map, Chebyshev map, Piecewise Linear map. However, the application researches about chaos are limited to the fields of data encryption and secure communication. In the data encryption systems, chaotic sequences can be used as the secret key to guarantee the safety of data and prohibit the juggle and steal unlawfully towards the data we sent. Generally, in the CDMA (code divide multiple access) communication system, we take the m and GOLD sequences as the PN (pseudonoise) code. Such conventional sequences get the merits of good auto-correlation and cross-correlation features. However the number-limited and short-period features of conventional sequence affect the performance of system greatly. Many researches have been done to create pseudo-random binary sequence which can be a substitute of conventional sequence. The sequences based on chaotic system get the traits of white noise can be the PN code of CDMA system. Many papers proved its feasibility.Having analyzed the chaos theory thoroughly, we choose a model carefully that can be easily realized by hardware. Now I will introduce the work of this paper form following three aspects: first, we bring forward a way to generate gauss sequences by chaotic system. Besides, we put forward a methods to produce PN sequences based on...