Noise auxiliary encryption and signal recovery method of broadband access network

Abstract

The present invention discloses a noise auxiliary encryption and signal recovery method of a broadband access network. The method is characterized in that noise signals of pilot frequency subcarriers and preambles, namely M+1 noise QAM symbols n1 to n(M+1), and the distribution of the pilot frequency subcarriers are obtained by the one-dimensional logistic mapping (chaotic mapping), and an N*N switching matrix Msw is obtained according to the distribution of the pilot frequency subcarriers. During the encryption process, an original signal and the noise signal are switched by the switching matrix Msw, so that not only the noise signal is inserted in the original signal, but also the distribution of the original signals is changed. At a receiving terminal, the pilot frequency subcarriers and the preambles loaded with the noise signals recover the original signals by a method reverse with a sending terminal. According to the present invention, and during the encryption process, the noise signal used for signal recovery is added in a useful signal randomly, and the original useful signal itself is disturbed and reconstructed, so that an invalid intruder can not obtain all useful information from an encryption signal if not having a secret key.

Description

technical field [0001] The invention belongs to the technical field of optical communication, and more specifically relates to a noise-assisted encryption and signal recovery method of a broadband access network. Background technique [0002] Optical OFDM passive optical network has been extensively studied as a candidate technology for next-generation broadband access networks, because this modulation technique has high spectrum efficiency, strong robustness to fiber dispersion, and very flexible dynamic Advantages of bandwidth allocation. Considering the rapid growth of the number of end users, these users have to share the limited bandwidth. Therefore, in the access network, the privacy, privacy and lack of security of communication have become one of the main problems of communication security. [0003] At present, various encryption technologies have been proposed to improve the security and integrity of communication data, and information authentication has become a c...

AI Technical Summary

Problems solved by technology

For example, in 2011, in the literature [L.Zhang, X.Xin, B.Liu, and Y.Wang, "SecureOFDM-PON based on chaos scrambling," IEEE Photon.Technol.Lett., 23(14), pp.998 –1000,2011] The encryption scheme proposed is based on the medium access control layer and uses interleaving. However, due to the extremely high accuracy of the chaotic synchronization of the encryption scheme, a high-cost encryption and decryption circuit is required, which increases the cost of OFDM PON. , the scheme cannot be widely used

The scheme proposed in the application publication number CN10341674A and titled "A Encryption Method for Broadband Access Network" published on November 20, 2013 is to select part of the subcarriers for noise loading. This method only Using the traditional signal recovery algorithm, noise is generated using PRBS, which is directly removed at the receiving end, and is not used for any signal recovery, and only noise is added to change the original signal, that is, noise is inserted into the original signal, and the original signal can be obtained after the noise is directly removed, so The distribution of the original signal is not processed, and the security needs to be further improved

Images