Microwave Modules for High Capacity Urban Radio Systems with 128 QAM modulation

2000 ◽  
Author(s):  
Barbara Gabbrielli ◽  
Giovanni Gilardi
Keyword(s):  
High Capacity ◽  
Qam Modulation ◽  
Radio Systems

scholarly journals Dithering Analysis in an Orthogonal Frequency Division Multiplexing-Radio over Fiber Link

2016 ◽  
Vol 6 (3) ◽  
pp. 1112
Author(s):  
Fakhriy Hario P ◽  
Adhi Susanto ◽  
I Wayan Mustika ◽  
Sevia M Idrus ◽  
Sholeh Hadi P
Keyword(s):  
Optical Fibers ◽  
Orthogonal Frequency Division Multiplexing ◽  
High Efficiency ◽  
Power Level ◽  
High Capacity ◽  
Coherent Detection ◽  
Frequency Division ◽  
Close Proximity ◽  
Qam Modulation ◽  
Fiber Link

Nonlinearity is one major problem broadband communication faced on utilizing the high capacity of optical fibers. That is due to scattering  phenomenon, which results in the deviations of wavelengths and energies. The dithering method is applied in the attempt to reduce those scatterings. In this paper, we propose the performance of a dithering technique based new system OFDM-RoF using two modulator scheme and coherent detection to alleviate the characteristics nonlinearity applied on the system. The dithering technique inputs signal externally to the signal processing systems to eliminate the effects of nonlinearity. Here, we report the performance of a dithering technique based on the OFDM-RoF, the results our experiment showed that the applied dithering with 16 QAM modulation can make the system more reliable and increases  the power level 1.55% with 193.1 THz, 2% with  100 THz and 1.99% ~ 200 THz, the best condition are with f<sub>d</sub> &lt; f<sub>c</sub>. However, all condition close proximity in the parameters OLP (optical launch power), BER and SER measurement. The result demonstrated a high efficiency and good power in which the OLP operated 6.396 dBm / 4.361 E-3 W~fd 200 THz, 3.578 dBm / 2.279 E-3 W~fd 193.1 THz and 6.420 dBm / 4.3384 E-3 W~100 THz. The best BER value is achieved at 0.33 and SER 0.78 at 5 km~f<sub>d</sub> 100 THz, 0.33 and 0.768 for 10 km~fd 193.1 THz, 0.478 and 0.92 for 50 km~fd 193.1 THz.

scholarly journals Quantum dot multi-wavelength lasers for Tbit/s coherent communications and 5G wireless networks -INVITED

2020 ◽  
Vol 238 ◽  
pp. 01003
Author(s):  
Z.G. Lu ◽  
J.R. Liu ◽  
Y.X. Mao ◽  
K. Zeb ◽  
G.C. Liu ◽  
...  
Keyword(s):  
Quantum Dot ◽  
High Speed ◽  
High Capacity ◽  
Modulation Formats ◽  
Qam Modulation ◽  
Optical Modes ◽  
Multi Wavelength ◽  
Dfb Laser ◽  
Technical Specifications ◽  
Transmission Link

We will present the design, growth, fabrication, electronic control and packaging of the InAs/InP quantum dot (QD) multi-wavelength lasers (MWLs) developed by AEP of NRC in Canada. Their key technical specifications include L-I-V curves, optical and RF beating spectra, relative intensity noise (RIN), and optical phase noise of each individual wavelength channel, as well as timing jitter are investigated. Data bandwidth transmission capacity of 5.376 Tbit/s and 10.3 Tbit/s respectively in the PAM-4 and 16-QAM modulation formats are demonstrated by only using a single QD MWL chip. We have also developed a novel monolithic InAs/InP QD dual-wavelength (DW) DFB laser as a compact optical beat source to generate millimeter-wave (MMW) signals. Because of using a common cavity, highly coherent and correlated optical modes with optical linewidth as low as 15.83 kHz, spectrally pure MMW signals around 46.8 GHz with a linewidth down to 26.1 kHz were experimentally demonstrated. By using this QD DW-DFB laser, a 1Gbaud (2Gbps) MMW over-fiber transmission link is demonstrated with PAM-4 signals. The results show that the demonstrated device is suitable for high speed high capacity MMW fiber-wireless integrated fronthaul of 5G networks.

Dithering Analysis in an Orthogonal Frequency Division Multiplexing-Radio over Fiber Link

2016 ◽  
Vol 6 (3) ◽  
pp. 1112
Author(s):  
Fakhriy Hario P ◽  
Adhi Susanto ◽  
I Wayan Mustika ◽  
Sevia M Idrus ◽  
Sholeh Hadi P
Keyword(s):  
Optical Fibers ◽  
Orthogonal Frequency Division Multiplexing ◽  
High Efficiency ◽  
Power Level ◽  
High Capacity ◽  
Coherent Detection ◽  
Frequency Division ◽  
Close Proximity ◽  
Qam Modulation ◽  
Fiber Link

Nonlinearity is one major problem broadband communication faced on utilizing the high capacity of optical fibers. That is due to scattering  phenomenon, which results in the deviations of wavelengths and energies. The dithering method is applied in the attempt to reduce those scatterings. In this paper, we propose the performance of a dithering technique based new system OFDM-RoF using two modulator scheme and coherent detection to alleviate the characteristics nonlinearity applied on the system. The dithering technique inputs signal externally to the signal processing systems to eliminate the effects of nonlinearity. Here, we report the performance of a dithering technique based on the OFDM-RoF, the results our experiment showed that the applied dithering with 16 QAM modulation can make the system more reliable and increases  the power level 1.55% with 193.1 THz, 2% with  100 THz and 1.99% ~ 200 THz, the best condition are with f<sub>d</sub> &lt; f<sub>c</sub>. However, all condition close proximity in the parameters OLP (optical launch power), BER and SER measurement. The result demonstrated a high efficiency and good power in which the OLP operated 6.396 dBm / 4.361 E-3 W~fd 200 THz, 3.578 dBm / 2.279 E-3 W~fd 193.1 THz and 6.420 dBm / 4.3384 E-3 W~100 THz. The best BER value is achieved at 0.33 and SER 0.78 at 5 km~f<sub>d</sub> 100 THz, 0.33 and 0.768 for 10 km~fd 193.1 THz, 0.478 and 0.92 for 50 km~fd 193.1 THz.

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