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Reduced-state noncoherent MLSD method for CPM in aeronautical telemetry

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The Journal of China Universities of Posts and Telecommunications 2020年第4期27卷 43-53页

作者： Zhou You Duan Ruifeng Jiang Bofeng School of Electoric and Information Engineering Beihang UniversityBeijing 100191China School of Information Science and Technology Beijing Forestry UniversityBeijing 100083China Beijing Xinwei Technology Group.Co. LtdBeijing 100193China

Due to high spectral efficiency and power efficiency, the continuous phase modulation(CPM) technique with constant envelop is widely used in range telemetry. How to improve the bit error rate(BER) performance of CPM and keep a reasonable computational complexity is the key of the entire telemetry system and the focus of research and engineering design. In this paper, a reduced-state noncoherent maximum likelihood sequence detection(MLSD) method for CPM is proposed. In the proposed method, the criterion of noncoherent MLSD is derived for CPM when the carrier phase is unknown. A novel Viterbi algorithm(VA) with modified state vector is designed to simplify the implementation of noncoherent MLSD. Both analysis and numerical results show that the proposed method reduces the computational complexity significantly and does not need accurate carrier phase recovery, which overcomes the shortage of traditional MLSD method. Additionally, the proposed method exceeds the traditional MLSD method when carrier phase deviation exists.

关键词： CPM low-complexity noncoherent detection MLSD Viterbi algorithm

Maximum-likelihood Block detection for CPM Signals

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The Journal of China Universities of Posts and Telecommunications 1995年第1期2卷 18-24页

作者： WuXuenong FengGuangzeng DepartmentofRadioEngineering NanjingUniversityofPostsandTelecommunicationsNanjing210003P.R.China De

This paper deals with noncoherent Maximum-likelihood Block detection (MLBD) of uncodedCPM signals (full response CPM and parrtal response CPM) over an additive white noise (AWGN)channel. Based on the work of W. Osborne and M. Simon ,this paper generalizes Maximum-likelihoodBlork detection. Then we focus on the error performance of MLBD, which is named one-symbol MLBDand N-symbol MLBD respectively. By computer simulation of CPFSK, 1RC and 2RC , it is found thatMLBD can improve the error performance over traditional noncoherent detection.

关键词： modulation continuous phase modulation noncoherent detection

Low complexity iterative differential decoding algorithm for multiband UWB communication systems

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Journal of Southeast University(English Edition) 2007年第1期23卷 7-11页

作者：金秀峰毕光国肖海勇东南大学移动通信国家重点实验室南京210096

Due to not requiring channel state information （CSI） at both the transmitter and the receiver, noncoherent ultra-wideband （UWB） incurs a performance penalty of approximately 3 dB in the required signal to noise ratio （SNR） compared to the coherent case. To overcome the gap, an effective differential encoding and decoding scheme for multiband UWB systems is proposed. The proposed scheme employs the parallel concatenation of two recursive differential unitary space-frequency encoders at the transmitter. At the receiver, two component decoders iteratively decode information bits by interchanging soft metric values between each other. To reduce the computation complexity, a decoding algorithm which only uses transition probability to calculate the log likelihood ratios （LLRs） for the decoded bits is given. Simulation results show that the proposed scheme can dramatically outperform the conventional differential and even coherent detection at high SNR with a few iterations.

关键词： multiband UWB multiple-input multiple-output (MIMO) system noncoherent detection group code iterative decoding

BLIND ADAPTIVE MULTIUSER DETECTOR FOR NONLINEARLY MODULATED SATELLITE MOBILE CDMA SYSTEMS

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Journal of Electronics(China) 2006年第3期23卷 338-340页

作者： Shao Shixiang Yang Longxiang Kyungsup Kwak ept. of Comm. Eng. Nanjing University of Posts and Telecommunications Nanjing 210003 China Institute of Comm. and Information Eng. Inha University Inchon South Korea

This paper presents a novel blind adaptive noncoherent decorrelative multiuser detector for nonlinearly modulated satellite mobile Code Division Multiple Access (CDMA) systems. By using the known signature waveforms of the counterpart earth station in the blind adaptive multiuser detector, the system performance has been improved obviously. The computation results about the convergence properties of the new detector and the previous detectors demonstrate that the proposed multiuser detector has better performance than previous multiuser detectors for nonlinearly modulated CDMA systems.

关键词： Mobile satellite communication Nonlinear Code Division Multiple Access (CDMA) system noncoherent detection Multiuser detection