Browsing by Author "Zeng, Wei-Siang"

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60-GHz optical/wireless MIMO system integrated with optical subcarrier multiplexing and 2x2 wireless communication
(2015-05-04)
Lin, Chi-Hsiang
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Lin, Chun-Ting
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Huang, Hou-Tzu
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Zeng, Wei-Siang
;
Chiang, Shou-Chih
This paper proposes a 2x2 MIMO OFDM Radio-over-Fiber scheme based on optical subcarrier multiplexing and 60-GHz MIMO wireless transmission. We also schematically investigated the principle of optical subcarrier multiplexing, which is based on a dual-parallel Mach-Zehnder modulator (DP-MZM). In our simulation result, combining two MIMO OFDM signals to drive DP-MZM gives rise to the PAPR augmentation of less than 0.4 dB, which mitigates nonlinear distortion. Moreover, we applied a Levin-Campello bit-loading algorithm to compensate for the uneven frequency responses in the V-band. The resulting system achieves OFDM signal rates of 61.5-Gbits/s with BER of 10(-3) over 25-km SMF transmission followed by 3-m wireless transmission. (C) 2015 Optical Society of America
Direct-Detection PDM-OFDM RoF System for 60-GHz 2 x 2 MIMO Wireless Transmission Without Polarization Tracking
(2018-09-01)
Huang, Hou-Tzu
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Sun, Chung-Shin
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Lin, Chun-Ting
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Wei, Chia-Chien
;
Zeng, Wei-Siang
This work experimentally demonstrates a 60-GHz direct-detection polarization division multiplexing and orthogonal frequency division multiplexing (PDM-OFDM) system that does not require polarization tracking. The frequency offset of un-modulated optical carriers and a novel training symbol design enable the estimation of optical polarization mixing and wireless multi-input-multi-output (MIMO) channels for signal demodulation. We also adopted an empty subcarrier to mediate noise enhancement. Simulation and experiment results both demonstrate the feasibility of this approach. With pre-compensation, we achieved a BER of 1 x 10(-3) under all polarization states over 10-km fiber and 3-m wireless MIMO transmission. The maximal allowable transmission data rate of up to 52 Gb at the worst case of states of polarization can he achieved.
Direct-Detection PDM-OFDM RoF System for 60-GHz Wireless VHMO transmission without Polarization Tracking
(2015)
Huang, Hou-Tzu
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Sun, Chung-Shin
;
Lin, Chun-Ting
;
Wei, Chia-Chien
;
Zeng, Wei-Siang
This work experimentally demonstrates a 60-GHz direct-detection PDM-OFDM system without polarization tracking at the receiver. A BER of 3.8x10(-3) was achieved with all states of polarization over 10-km fiber and 3-m wireless MIMO transmission.
Spectrally efficient polarization multiplexed direct-detection OFDM system without frequency gap
(2016-01-25)
Wei, Chia-Chien
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Zeng, Wei-Siang
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Lin, Chun-Ting
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光電系統研究所
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Institute of Photonic System
We experimentally demonstrate a spectrally efficient direct-detection orthogonal frequency-division multiplexing (DD-OFDM) system. In addition to polarization-division multiplexing, removing the frequency gap further improves the spectral efficiency of the OFDM system. The frequency gap between a reference carrier and OFDM subcarriers avoids subcarrier-to-subcarrier beating interference (SSBI) in traditional DD-OFDM systems. Without dynamic polarization control, the resulting interference after square-law direct detection in the proposed gap-less system is polarization-dependent and composed of linear inter-carrier interference (ICI) and nonlinear SSBI. Thus, this work proposes an iterative multiple-input multiple-output detection scheme to remove the mixed polarization-dependent interference. Compared to the previous scheme, which only removes ICI, the proposed scheme can further eliminate SSBI to achieve the improvement of similar to 7 dB in signal-to-noise ratio. Without the need for polarization control, we successfully utilize 7-GHz bandwidth to transmit a 39.5-Gbps polarization multiplexed OFDM signal over 100 km. (C) 2016 Optical Society of America