Study on Frame Structure Detection in Physical Layer Based on Multi-fractal Spectrum

In order to achieve the justification of whether a frame structure detection exists or not under the condition that protocol is unknown, an algorithm for frame structure detection in physical layer based on multi-fractal spectrum is proposed. Firstly, the relationship between bias and occurrence probability of 0 and 1 bit is defined. Through analyzing the generation principle of channel code, scrambler, frame sequence and calculating the occurrence probability of 0 and 1 bit, the conclusion is that the bias of synchronization word is larger than the others. Then, due to the above conclusion and the character that bias distribution can be described by multi-fractal spectrum, the width of multi-fractal spectrum of split sequences is calculated. At last, frame structure can be detected by observing distribution of the width of multi-fractal spectrum of split sequences. Simulation results show the proposed algorithm is effective, and it has value in engineering application.