CAJ | 학술논문

针对星载船舶自动识别系统( AIS )无法避免的信号混叠问题，研究了AIS系统中应用最广泛的1比特差分和2比特差分解调，提出了一种1、2、3比特联合差分反馈的AIS信号非相干解调算法。该算法基于贝叶斯线性模型建立了最大似然估计的1、2、3比特联合差分解调结构，验证了在加性高斯信道中该算法比传统非相干解调算法有更好的抗信号混叠能力。仿真实验表明：该算法的解调误码率与1、2比特联合差分及2、3比特联合差分相比，当误码率( BER)等于10-2时，在加性高斯信道(AWGN)下具有1.5 dB的性能优势，同道干扰信道(CCI)下具有1~2 dB的性能优势。
침대성재선박자동식별계통( AIS )무법피면적신호혼첩문제，연구료AIS계통중응용최엄범적1비특차분화2비특차분해조，제출료일충1、2、3비특연합차분반궤적AIS신호비상간해조산법。해산법기우패협사선성모형건립료최대사연고계적1、2、3비특연합차분해조결구，험증료재가성고사신도중해산법비전통비상간해조산법유경호적항신호혼첩능력。방진실험표명：해산법적해조오마솔여1、2비특연합차분급2、3비특연합차분상비，당오마솔( BER)등우10-2시，재가성고사신도(AWGN)하구유1.5 dB적성능우세，동도간우신도(CCI)하구유1~2 dB적성능우세。
A non-coherent algorithm based on combined 1 , 2 and 3-bit differential detection with decision feedback is proposed in this paper to demodulate AIS ( Automatic Identification System) signals, so as to enhance the abilities of the widely-used 1 and 2-bit differential detection ones in adaptation to co-channel interference( CCI) . The algorithm is based on the Bayesian linear model, and establishes a maximum like-lihood detection formulation. Theoretical analysis demonstrates the predominance of the proposed algorithm against the existing non-coherent counterparts in adaption to CCI. Simulation results then show that, when compared with the two algorithms developed via 1 and 2-bit joint differential detection and 2 and 3-bit joint differential detection with the bit error rate( BER) is set to 10-2 , the proposed algorithm gains an im-provement of 1 . 5 dB in signal-to-noise ratio ( SNR ) in the case of additive white Gaussian noise ( AWGN) , and an improvement of 1~2 dB in signal-to-interference ratio ( SIR) .