Coherent optical wireless optical communication transmission method and system, storage medium and equipment

Abstract

The invention belongs to the technical field of free space optical communication, and discloses a coherent optical wireless optical communication transmission method and system, a storage medium and equipment, and the method comprises the steps: carrying out the symbol mapping of data through three variables: a phase, a polarization state and a data symbol bit, so as to generate baseband symbol streams in X and Y polarization states; and enabling the four paths of baseband signals to be sequentially subjected to I / Q imbalance compensation, channel equalization, time sequence recovery, carrierfrequency offset compensation and carrier phase offset compensation to obtain two paths of symbol data streams corresponding to the generated baseband signals. Phase noise caused by atmospheric turbulence can be effectively suppressed, and crosstalk between polarization states in the same symbol time slot period can be effectively avoided by cross-modulating symbol information in two adjacent symbol periods in the orthogonal polarization state. Therefore, the performance of the traditional atmospheric coherent light communication system based on the PSK or QAM modulation mode can be effectively improved, and the transmission distance of the atmospheric laser communication system is expanded.

Description

technical field [0001] The invention belongs to the technical field of free space optical communication, and in particular relates to a coherent optical wireless optical communication transmission method, system, storage medium and equipment. Background technique [0002] At present, free-space optical communication technology is a key technology for the development of rapid deployment systems, security systems, communication systems, real-time surveillance and monitoring systems. The free-space optical communication system has many advantages, such as short deployment time, relatively cheap devices, anti-electromagnetic interference, and no restrictions on radio licenses, etc., especially high bandwidth that is incomparable to radio frequency communication. In the commercial field, it can provide broadband wireless extension for the Internet backbone network, for the rapid development of no-delay web browsing, database access, e-commerce, access and transmission of big data...

AI Technical Summary

Problems solved by technology

Since the transmitted symbols are independent and irrelevant, even if correlated phase noise is introduced on the symbols, this noise correlation cannot be used for noise suppression at the receiving end

Moreover, crosstalk between two polarization states in the same symbol slot period is also prone to occur, which further reduces the performance of the system.

Therefore, the disadvantage of the existing coherent optical communication technology based on PSK or QAM modulation is that it cannot effectively suppress the phase noise caused by atmospheric turbulence, and there will be crosstalk between the two polarization states

[0004] Through the above analysis, the problems and defects of the existing technology are: the existing coherent optical communication technology based on PSK or QAM modulation mode cannot effectively suppress the phase noise caused by atmospheric turbulence, and crosstalk will occur between the two polarization states

[0005] The difficulty in solving the above problems and defects is: In order to effectively suppress the phase noise caused by atmospheric turbulence, the existing coherent optical communication technology based on PSK or QAM modulation has to rely on complex and expensive adaptive optics systems. Although this system is effective , but the increase in system cost even exceeds the cost of the communication system itself, which is unbearable for cost-sensitive commercial communication systems

Images