Carrier Phase Recovery for Optical Coherent M-QAM Communication Systems Using Harmonic Decompositionbased Maximum Loglikelihood Estimators

Using coherent optical detection and digital signal processing, laser phase noise and equalization enhanced phase noise can be effectively mitigated using the feed-forward and feed-back carrier phase recovery approaches. In this paper, theoretical analyses of feed-back and feed-forward carrier phase recovery methods have been carried out in the long-haul high-speed n-level phase shift keying (n-PSK) optical fiber communication systems, involving a one-tap normalized least-mean-square (LMS) algorithm, a block-wise average algorithm, and a Viterbi-Viterbi algorithm. The analytical expressions for evaluating the estimated carrier phase and for predicting the bit-error-rate (BER) performance (such as the BER floors) have been presented and discussed in the n-PSK coherent optical transmission systems by considering both the laser phase noise and the equalization enhanced phase noise. The results indicate that the Viterbi-Viterbi carrier phase recovery algorithm outperforms the one-tap normalized LMS and the block-wise average algorithms for small phase noise variance (or effective phase noise variance), while the one-tap normalized LMS algorithm shows a better performance than the other two algorithms for large phase noise variance (or effective phase noise variance). In addition, the one-tap normalized LMS algorithm is more sensitive to the level of modulation formats.

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Simulasi Sinkronisasi Carrier pada Modulasi Digital menggunakan Matlab

ELKOMIKA Jurnal Teknik Energi Elektrik Teknik Telekomunikasi & Teknik Elektronika ◽

10.26760/elkomika.v2i2.100 ◽

2014 ◽

Vol 2 (2) ◽

pp. 100

Author(s):

DWI ARYANTA ◽

ARSYAD RAMADHAN DARLIS ◽

WIRDA SRI FARHANI

Keyword(s):

Carrier Phase ◽

Communication Systems ◽

Digital Communication ◽

Similar Data ◽

Receiver Side ◽

Carrier Synchronization ◽

Phase Recovery ◽

Recovery Method ◽

Qam Modulation ◽

Digital Communication Systems

ABSTRAKDalam sistem komunikasi digital, salah satu manfaat teknik pengkodean adalah sebagai efisiensi bandwidth. Pada kanal komunikasi, adanya noise akan mengganggu dan menurunkan kinerja sistem komunikasi digital. Hal ini menyebabkan terjadinya kesalahan pendeteksian sinyal pembawa, yang mengakibatkan terjadi perubahan bit atau simbol pada sisi penerima. Untuk mengurangi kesalahan deteksi, maka dibutuhkan suatu mekanisme sinkronisasi carrier di sisi penerima untuk mendapatkan data yang serupa dengan data yang dikirim. Simulasi sinkronisasi carrier pada penelitian ini menggunakan metode carrier phase recovery pada modulasi digital M-PSK dan M-QAM dengan level modulasi 4 sampai dengan 32, menggunakan software Matlab versi 7.9. Hasil pengujian sistem yang telah dilakukan pada Eb/No dengan rentang 0 hingga 30 dB menunjukkan, adanya peningkatan kinerja sistem pada modulasi M-PSK dari 0,01352 sampai dengan 0,8546, dan pada modulasi M-QAM dari 0,0256 sampai dengan 0,7867.Kata Kunci: M-PSK, M-QAM, Kanal AWGN, BER, Eb/No, Phase RecoveryABSTRACTThe digital communication systems, one of the benefits coding techniques are as bandwidth efficiency. The communication channel, the presence of noise will disrupt and degrade the performance of digital communication systems. This leads to error detection of the carrier, resulting in a change of bits or symbols at the receiver side. To reduce the detection error, there is a need carrier synchronization at the receiver side to obtain similar data with the data sent. Simulation of carrier synchronization in this study using the carrier phase recovery method in digital modulation M-PSK and M-QAM modulation with levels 4 to 32, using Matlab software version 7.9. The results of system testing has been done on the Eb / No ranging from 0 to 30 dB shows, an increase in the performance of the system on the M-PSK modulation from 0.01352 to 0.8546, and the M-QAM modulation from 0.0256 to 0 , 7867. Keywords: M-PSK, M-QAM, AWGN Channel, BER, Eb/No, Phase Recovery

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