用于太赫兹通信的双向全并行相位估计算法

Bidirectional fully parallel phase estimation algorithm for terahertz communication

摘要:

在太赫兹通信的超宽带应用场景下，太赫兹载波是通过多次倍频实现，因而导致相噪严重恶化。基于太赫兹频率下的多极/零相位噪声模型，在传统的盲相位估计算法的基础上，提出了一种全并行化的相位估计算法。该算法通过在每个并行数据中插入导频，将导频相噪信息作为初始相位对并行数据进行相位扩展及旋转鉴相。借鉴传统盲相位估计算法的最佳相位估计值的判决选择思路，同时利用前一时刻导频和当前时刻导频，对当前并行数据从前后两个方向进行相位估计并对前后两个估计相位基于距离前后导频的位置进行加权求和以获得最佳相位估计信息。经过仿真验证，通过该算法后残余相噪在1 MHz和10 MHz处分别降低10 dBc/Hz和25 dBc/Hz。

Abstract:

There exists severe deterioration of phase noise in the ultra wideband application scenario of terahertz communication, since terahertz carriers are achieved through multiple frequency doubling. Based on the multipole/zero phase noise model at terahertz frequency, a fully parallelized phase estimation algorithm is proposed on the basis of traditional blind phase estimation algorithms. This algorithm inserts pilots into each parallel data and uses pilot phase noise information as the initial phase to perform phase extension and rotation phase detection on the parallel data. Referring to the traditional blind phase estimation algorithm, the decision selection approach for the optimal phase estimation value is adopted. At the same time, the previous and current time pilots are employed to estimate the phase of the current parallel data from the front and back directions. The two estimated phases are weighted and summed based on the distance between the front and back pilots to obtain the optimal phase estimation information. After simulation verification, the residual phase noise is reduced by 10 dBc/Hz and 25 dBc/Hz at 1 MHz and 10 MHz, respectively, through this algorithm.