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This article mainly introduces what is pseudorandom sequence in programming technology. It is very detailed and has certain reference value. Friends who are interested must finish reading it.

Pseudorandom sequence is a definite sequence with some random characteristics. They are deterministic sequences generated by shift registers, but they have some random characteristics. Because it also has random characteristics, it is impossible to judge whether it is a true random sequence or a pseudo-random sequence from the characteristics of a generated sequence, but only according to the generation method of the sequence.

If a sequence, on the one hand, it can be pre-determined, and can be repeatedly produced and copied; on the other hand, it has the random characteristics of a random sequence (that is, statistical properties), we call this sequence pseudo-random sequence.

Pseudorandom sequence is a definite sequence with some random characteristics. They are deterministic sequences generated by shift registers, but they have some random characteristics. Because it also has random characteristics, it is impossible to judge whether it is a true random sequence or a pseudo-random sequence from the characteristics of a generated sequence, but only according to the generation method of the sequence. Pseudo-random sequence series have good randomness and correlation function close to white noise, and have pre-certainty and repeatability. These characteristics make pseudorandom sequences widely used, especially in CDMA systems as spreading codes has become a key problem in CDMA technology. The property is that the number of two elements in the sequence is roughly the same.

If the continuous occurrence of n elements is called an element run of length n, then the element run of length n in the sequence is twice as long as the element run of length n.

There is a definite relationship between sequence elements, but a special form of discrete signal with properties similar to random sequences, which can be expressed as

... , "1", "0", "1," 2,...

You can also take the elements in the symbol field GF (Q) (see the block code). The former is called binary sequence and the latter is called Q-ary sequence. But the most important thing in practice is the former. The length of the sequence can be finite or infinite. The latter mainly focuses on periodic sequences, that is, there is a minimum positive integer, which makes it periodic for all I.

When each element of a sequence is independent of each other and has the same distribution, it is called a random sequence. The practical application is mainly pseudo-random sequence. It means that there is a definite relationship between sequence elements, but it has the following properties similar to random sequences: ① in a finite length or a period, the difference in the number of elements is not more than 1, that is, close to equal probability; the probability of ② having the same value or l-long run is close to 1ql; ③ correlation function

It is p when τ = 0, and it does not exceed ±1 when τ 0, where p is the length or period of the sequence. In fact, sequences that generally meet the above conditions are sometimes called pseudorandom sequences.

Import numpy as npimport matplotlib.pyplot as plt# is used to display the Chinese label # plt.rcParams ['font.family'] = [' Simhei'] plt.rcParams ['font.sans-serif'] = [' Yahei consolas hybrid'] # to display the negative sign plt.rcParams ['axes.unicode_minus'] = False# A = 6N = 200x0 = 1m = 255v = np.zeros ([N] 1]) # print (v) x = np.arange (N) for k in np.arange (N): X2 = A*x0 x1 = x2% Mv1 = x1Ting 256v [k] = 2* (v1-0.5) x0 = x1#print (v.reshape (7L16)) plt.plot (x V) plt.xlabel ('k') plt.ylabel ('v') plt.title ('pseudorandom sequence') plt.show () above are all the contents of the article "what is pseudorandom sequence in programming technology" Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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