Browsing by Author "Ng'oma, Anthony"

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13.75-Gb/s OFDM Signal Generation for 60-GHz RoF System within 7-GHz License-Free Band via Frequency Sextupling
(2009)
Shih, Po-Tsung
;
Lin, Chun-Ting
;
Huang, Han-Sheng
;
Jiang, Wen-Jr
;
Chen, Jyehong
A 60-GHz RoF system with frequency sextupling is experimentally demonstrated. Based on modified SSB, a 13.75-Gb/s OFDM signal is generated within the 7-GHz license-free band. No penalty is observed after transmission over 25-km single-mode fiber.
2 x 2 MIMO radio-over-fiber system at 60 GHz employing frequency domain equalization
(2012-01-02)
Lin, Chun-Ting
;
Ng'oma, Anthony
;
Lee, Wei-Yuan
;
Wei, Chia-Chien
;
Wang, Chih-Yun
This work experimentally demonstrates the efficacy of the 2 x 2 multiple-input multiple-output (MIMO) technique for capacity improvement of a 60-GHz radio-over-fiber (RoF) system employing single-carrier modulation format. We employ frequency domain equalization (FDE) to estimate the channel response, including frequency response of the 60 GHz RoF system and the MIMO wireless channel. Using FDE and MIMO techniques, we experimentally demonstrate the doubling the of wireless data capacity of a 60 GHz RoF system to 27.15 Gb/s using 16-QAM modulation format, with transmission over 25 km of standard single-mode fiber and 3 m wireless distance. (C) 2011 Optical Society of America
2x21 Gbps Symmetrical Full-Duplex Transmission of OFDM Wireless Signals over a Bidirectional IMDD Radio-over-Fiber System at 60 GHz
(2010)
Shih, Po-Tsung
;
Ng'oma, Anthony
;
Lin, Chun-Ting
;
Annunziata, Frank
;
Chen, Jyehong
A full-duplex bidirectional 60 GHz RoF system for in-building wireless applications employing DSB IMDD techniques is experimentally demonstrated. Symmetrical 2x21 Gbps transmission over 500-m standard single mode fiber and 2.5-m wireless distance is successfully achieved.
31 Gbps RoF System Employing Adaptive Bit-Loading OFDM Modulation at 60 GHz
(2011-01-01)
Ng'oma, Anthony
;
Lin, Chun-Ting
;
He, Li-Ying Wang
;
Jiang, Wen-, Jr.
;
Annunziata, Frank
Record wireless data transmission of 31.4 Gbps within 7 GHz license-free band at 60 GHz is experimentally demonstrated using adaptive bit-loading OFDM modulation. Adaptive bit-loading OFDM also enables extended fiber transmission distances beyond 5km.
Direct-Detection PDM-OFDM RoF System for 60-GHz 2 x 2 MIMO Wireless Transmission Without Polarization Tracking
(2018-09-01)
Huang, Hou-Tzu
;
Sun, Chung-Shin
;
Lin, Chun-Ting
;
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.
MIMO-Enhanced Radio-over-Fiber System at 60 GHz
(2011-01-01)
Lin, Chun-Ting
;
Ng'oma, Anthony
;
Lee, Wei-Yuan
;
Wang, Chih-Yun
;
Lu, Tsung-Hung
We employ 2x2 MIMO spatial multiplexing to double the spectral efficiency of a 60GHz RoF system. A 27.15-Gbps 16-QAM MIMO signal with 3m wireless transmission is experimentally demonstrated within 7-GHz license -free spectrum at 60 GHz.
Performance Evaluation of a 60 GHz Radio-over-Fiber System Employing MIMO and OFDM Modulation
(2013-12-01)
Ho, Chun-Hung
;
Jiang, Wen-Jr
;
Sambaraju, Rakesh
;
Lee, Wei-Yuan
;
Lu, Tsung-Hung
Multiple-input-multiple-output (MIMO) technique for wireless communications is extensively used these days, especially to increase the spectral efficiency of new wireless communication systems like LTE, WiMAX, etc. MIMO in combination with robust modulation techniques like orthogonal frequency division multiplexing (OFDM) provides a good solution for high data rate wireless links. In this paper, the performance of MIMO for a 60 GHz OFDM radio over fiber link is analyzed. System performance of the MIMO system for different antenna spacing is also studied. Using the optimum system parameters, a MIMO OFDM wireless link of up to 51 Gb/s was successfully demonstrated at 60 GHz in a bandwidth of <7 GHz, with a wireless transmission distance of up to 4 m and optical fiber transmission of 1 km. To our knowledge this is the highest data rate demonstrated in the 7 GHz band of 60 GHz.
Simple 14-Gb/s Short-Range Radio-Over-Fiber System Employing a Single-Electrode MZM for 60-GHz Wireless Applications
(2010-08-15)
Jiang, Wen-Jr
;
Lin, Chun-Ting
;
Ng'oma, Anthony
;
Shih, Po-Tsung
;
Chen, Jason Jyehong
This paper demonstrates the feasibility of a simple multigigabit-per-second (Gbps) radio-over-fiber (RoF) system employing multilevel orthogonal frequency-division-multiplexing (OFDM) signal modulation at 60 GHz and a single-electrode Mach-Zehnder modulator (MZM). In this paper, the impact of fiber chromatic dispersion and OFDM beat noise on the performance of the RoF system are investigated by theoretical analysis, VPI WDM-TransmissionMaker simulation and experimental demonstration. A 13.875-Gb/s QPSK OFDM signal occupying the full 7-GHz license-free band at 60 GHz with frequency multiplication for the RoF link is demonstrated. After 3 km of standard single-mode fiber transmission with no dispersion compensation, the power penalty is less than 3 dB.
Transmission of 20-Gb/s OFDM signals occupying 7-GHz license-free band at 60 GHz using a RoF system employing frequency sextupling optical up-conversion
(2010-06-07)
Shih, Po-Tsung
;
Lin, Chun-Ting
;
Jiang, Wen-Jr
;
Huang, Han-Sheng
;
Chen, Jyehong
This work describes a proposed 60-GHz radio-over-fiber (RoF) system employing a frequency sextupling optical up-conversion scheme. Based on the modified single sideband modulation scheme, spectrally efficient vector signals were transmitted with no performance degradation due to dispersion-induced fading. Wavelength-division-multiplexed optical up-conversion can be realized using the proposed system. Since the required transmitter bandwidth is significantly reduced, radio-frequency components with lower bandwidth and higher reliability can be utilized. Both 13.75-Gb/s QPSK-OFDM and 20.625-Gb/s 8QAM-OFDM signals were experimentally demonstrated. After transmission over 25-km of standard single mode fiber, no significant received power penalty was observed. (C) 2010 Optical Society of America
Transmission of wireless signals using space division multiplexing in few mode fibers
(2018-08-06)
Liang, Xiaojun
;
Li, Wei-Ling
;
Wood, William A.
;
Downie, John D.
;
Hurley, Jason E.
Evolution of next generation wireless networks brings challenges to efficiently transmit a large amount of data from a base station to a remote antenna unit. We investigate a space division multiplexing technique that employs few mode fibers (FMFs) to transmit 3 x 3 MIMO wireless signals, aiming to employ a common digital signal processing (DSP) unit to equalize both the fiber and wireless channel. We optimize system parameters and obtain above 28 dB and 23 dB signal-to-interference and noise ratio (SINR) for 3 meters wireless systems with 500 m and 2 km FMF, which correspond to the transmission capacity of 578 Mb/s and 468 Mb/s using a 20 MHz bandwidth, respectively. Moreover, we analyze that the nonlinear spectrum distortion due to the combined effect of nonlinearity in the directly modulated laser and the differential mode delay in multimode fibers and validate it by simulations. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement