Three-dimensional probability forming carrier-free amplitude phase modulation method

Abstract

The invention discloses a three-dimensional probability forming carrier-free amplitude phase modulation method. According to the method, maximum CFM serves as a design principle, input original data firstly enter a geometric forming probability forming unit, three-dimensional constellation geometric forming with a regular tetrahedron as a primitive is conducted, and probability forming is conducted according to Maxwell-Boltzmann distribution; a constellation mapping unit is entered to perform three-dimensional constellation mapping; an up-sampling unit is entered, and multiple up-sampling operations required before a filter are carried out; then three filter units are entered, so that information of the constellation symbol in three dimensions respectively enters the three mutually orthogonal FIR filters for shaping and filtering; finally, the three paths of parallel signals are added under the effect of an adder unit, 3D-PS-CAP modulation is completed, and constellation points are gathered inwards as much as possible; then probability forming is carried out according to Maxwell-Boltzmann distribution, the probability distribution of the constellation is optimized, the average energy of the constellation is further reduced, and the CFM of the constellation is increased. And the bit error rate performance of the modulation system is effectively improved through the combined effect of geometric forming and probability forming.

Description

technical field [0001] The invention belongs to the technical field of optical transmission and communication, and in particular relates to a three-dimensional probability shaping method for amplitude-phase modulation without carrier. Background technique [0002] In recent years, with the vigorous development of many high-speed new services such as 5G, Internet of Things, augmented reality / virtual reality, big data, and cloud computing, more and more traffic exchange and data transmission will be concentrated in the data center or data Between centers, people's demand for the capacity of short-distance optical communication systems is growing explosively. Compared with coherent detection systems, intensity modulation / direct detection (IMDD) is widely used in short-range communication systems due to its advantages in cost, energy consumption, and packaging to meet this urgent capacity demand . IMDD-based pulse amplitude modulation (PAM), discrete multi-tone (DMT) modulatio...

AI Technical Summary

Problems solved by technology

However, at present, most of the geometric modeling and probabilistic modeling are carried out in two dimensions, and rarely in three or higher dimensions.

Images