scholarly journals A ROF Access Network for Simultaneous Generation and Transmission Multiband Signals Based on Frequency Octupling and FWM Techniques

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Hui Zhou ◽  
Yunlong Shen ◽  
Ming Chen ◽  
Jun Cheng ◽  
Yuting Zeng
Keyword(s):  
Optical Filter ◽  
Access Network ◽  
Optical Amplifier ◽  
Base Stations ◽  
Frequency Interval ◽  
60 Ghz ◽  
Simultaneous Generation ◽  
Optical Signals ◽  
Tunable Optical Filter ◽  
Rf Signal

We report a radio-over-fiber (ROF) access network with multiple high-repetive frequency mm-wave signals generation utilizing a dual-parallel Mach-Zehnder modulator (DP-MZM) and an semiconductor optical amplifier (SOA) for multiple base stations (BSs). In the scheme, at the central station (CS), signal and pump with frequency interval of 8fRF are generated by properly adjusting the parameters of the DP-MZM. After FWM in a SOA, new converted optical signals are obtained. Two tones of the optical signals are selected by using tunable optical filter (TOF), which are then sent into a photodiode (PD) to generate multiple mm-wave signals with different frequencies (8fRF, 16fRF, and 24fRF) for different BSs. Based on the proposed scheme, the mm-wave signals with frequencies of 20, 40, and 60 GHz carrying 2.5 Gb/s signal by a 2.5GHz RF signal have been generated by numerical simulation. Simulation results show that the proposed ROF system architecture with multiple-frequency millimeter-wave signals generation serving multiple BSs can work well. This scheme can raise the capacity of ROF system, reduce the requirement of the repetitive frequency of the driven RF signal, and support multiple mm-wave wireless access for BSs.

A WAVELENGTH CONVERSION BASED ON CROSS-GAIN MODULATION OF A SEMICONDUCTOR OPTICAL AMPLIFIER FIBER RING LOOP

2009 ◽  
Vol 18 (02) ◽  
pp. 309-318
Author(s):  
YONGAN TANG ◽  
AZAD SIAHMAKOUN ◽  
GRANIERI SERGIO ◽  
SEIFU TEFERRA ◽  
BRANISLAV VLAHOVIC ◽  
...  
Keyword(s):  
Semiconductor Optical Amplifier ◽  
Wavelength Conversion ◽  
Optical Filter ◽  
Optical Amplifier ◽  
Optical Signal ◽  
Gain Modulation ◽  
Fiber Ring ◽  
Cross Gain Modulation ◽  
Tunable Optical Filter ◽  
Scaling Down

We investigate the cross-gain modulation (XGM) in a semiconductor optical amplifier (SOA) fiber ring loop theoretically and experimentally. Based on the XGM, a wavelength conversion is designed. We experimentally carry out an SOA wavelength conversion, which converts a 20 MHz sinusoidal modulated input optical signal at a wavelength of 1317 nm to an output optical signal at a wavelength of 1314.3 nm. In this type of wavelength conversion, a tunable optical filter is utilized to select the target wavelength of the output signal from the fiber ring loop, and this target wavelength signal is accumulated and amplified as the resonance of the fiber ring loop. The introduction of the tunable optical filter into the fiber ring loop system makes it very easy to obtain any desired target wavelength from this XGM wavelength conversion system; this remarkable property means that the SOA wavelength conversions have broader applications in optical networking and beyond. Higher frequency modulation XGM wavelength conversion may be obtained by scaling down the length of the fiber ring loop.

scholarly journals Performance Evaluation of Direct-Link Backhaul for UAV-Aided Emergency Networks

Sensors ◽  
2019 ◽  
Vol 19 (15) ◽  
pp. 3342 ◽  
Author(s):  
German Castellanos ◽  
Margot Deruyck ◽  
Luc Martens ◽  
Wout Joseph
Keyword(s):  
Network Performance ◽  
Access Network ◽  
Network Capacity ◽  
Base Stations ◽  
60 Ghz ◽  
City Center ◽  
Flight Height ◽  
Backhaul Networks ◽  
The City ◽  
Cell Base

Today’s wireless networks provide us reliable connectivity. However, if a disaster occurs, the whole network could be out of service and people cannot communicate. Using a fast deployable temporally network by mounting small cell base stations on unmanned aerial vehicles (UAVs) could solve the problem. Yet, this raises several challenges. We propose a capacity-deployment tool to design the backhaul network for UAV-aided networks and to evaluate the performance of the backhaul network in a realistic scenario in the city center of Ghent, Belgium. This tool assigns simultaneously resources to the ground users—access network—and to the backhaul network, taking into consideration backhaul capacity and power restrictions. We compare three types of backhaul scenarios using a 3.5 GHz link, 3.5 GHz with carrier aggregation (CA) and the 60 GHz band, considering three different types of drones. The results showed that an optimal UAV flight height (80 m) could satisfy both access and backhaul networks; however, full coverage was difficult to achieve. Finally, we discuss the influence of the flight height and the number of requesting users concerning the network performance and propose an optimal configuration and new mechanisms to improve the network capacity, based on realistic restrictions.

Performance and Reliability of a MEMS-based tunable optical filter operating in the 1565 nm-1525 nm wavelength range

2002 ◽  
Vol 722 ◽  
Author(s):  
T. S. Sriram ◽  
B. Strauss ◽  
S. Pappas ◽  
A. Baliga ◽  
A. Jean ◽  
...  
Keyword(s):  
Silicon Nitride ◽  
Line Width ◽  
Insertion Loss ◽  
Optical Filter ◽  
Single Mode ◽  
Single Mode Fiber ◽  
Reliability Testing ◽  
Silicon Nitride Membrane ◽  
Tunable Optical Filter ◽  
Extensive Performance

AbstractThis paper describes the results of extensive performance and reliability characterization of a silicon-based surface micro-machined tunable optical filter. The device comprises a high-finesse Fabry-Perot etalon with one flat and one curved dielectric mirror. The curved mirror is mounted on an electrostatically actuated silicon nitride membrane tethered to the substrate using silicon nitride posts. A voltage applied to the membrane allows the device to be tuned by adjusting the length of the cavity. The device is coupled optically to an input and an output single mode fiber inside a hermetic package. Extensive performance characterization (over operating temperature range) was performed on the packaged device. Parameters characterized included tuning characteristics, insertion loss, filter line-width and side mode suppression ratio. Reliability testing was performed by subjecting the MEMS structure to a very large number of actuations at an elevated temperature both inside the package and on a test board. The MEMS structure was found to be extremely robust, running trillions of actuations without failures. Package level reliability testing conforming to Telcordia standards indicated that key device parameters including insertion loss, filter line-width and tuning characteristics did not change measurably over the duration of the test.

Electrically tunable optical filter for infrared wavelength using liquid crystals in a Fabry–Perot étalon

1990 ◽  
Vol 57 (17) ◽  
pp. 1718-1720 ◽  
Author(s):  
J. S. Patel ◽  
M. A. Saifi ◽  
D. W. Berreman ◽  
Chinlon Lin ◽  
N. Andreadakis ◽  
...  
Keyword(s):  
Liquid Crystals ◽  
Optical Filter ◽  
Infrared Wavelength ◽  
Tunable Optical Filter ◽  
Fabry Perot

Network Throughput and Outage Analysis in a Poisson and Matérn Cluster based LTE-Advanced Small Cell Networks

2021 ◽  
Author(s):  
Joydev Ghosh
Keyword(s):  
Outage Probability ◽  
Cell Formation ◽  
Access Network ◽  
Small Cell ◽  
Network Throughput ◽  
Base Stations ◽  
Small Cells ◽  
Network Cell ◽  
Lte Advanced ◽  
The Impact

<div>In LTE-A (LTE-Advanced), the access network cell formation is an integrated form of outdoor unit and indoor unit. With the indoor unit extension the access network becomes heterogeneous (HetNet). HetNet is a straightforward way to provide quality of service (QoS) in terms better network coverage and high data rate. Although, due to uncoordinated, densely deployed small cells large interference may occur, particularly in case of operating small cells within the spectrum of macro base stations (MBS). This paper probes the impact of small cell on the outage probability and the average network throughput enhancement. The positions of the small cells are retained random and modelled with homogeneous Poisson Point Process (PPP) and Matérn Cluster process (MCP). The paper provides an analytic form which permits to compute the outage probability, including the mostly applied fast fading channel types. Furthermore, simulations are evaluated in order to calculate the average network throughput for both random processes. Simulation results highlights that the network throughput remarkably grows due to small cell deployment.</div>

scholarly journals Simultaneous generation of independent wired and 60-GHz wireless signals in an integrated WDM-PON-RoF system based on frequency-sextupling and OCS-DPSK modulation

2012 ◽  
Vol 20 (13) ◽  
pp. 14648 ◽  
Author(s):  
Liang Zhang ◽  
Xiaofeng Hu ◽  
Pan Cao ◽  
Qingjiang Chang ◽  
Yikai Su
Keyword(s):  
60 Ghz ◽  
Simultaneous Generation ◽  
Wdm Pon

Transmission of Signals Using White LEDs for VLC Application

MRS Advances ◽  
2016 ◽  
Vol 1 (55) ◽  
pp. 3661-3666 ◽  
Author(s):  
P. Louro ◽  
V. Silva ◽  
J. Costa ◽  
M. A. Vieira ◽  
M. Vieira
Keyword(s):  
Optical Filter ◽  
Visible Light Communication ◽  
Indoor Navigation ◽  
Optical Signals ◽  
White Leds ◽  
Indoor Location ◽  
Optical Channels ◽  
Wavelength Sensitivity ◽  
Location Algorithm ◽  
The Individual

ABSTRCTIn this paper a photodetector working as an active optical filter device is used to detect modulated visible optical signals for applications based on Visible Light Communication (VLC). The proposed application demonstrates the viability of indoor positioning using VLC technology established by the modulation of indoor ultra-bright RGB white LEDs. The signals of the internal red and blue chips of the white LEDs were modulated at specific frequencies and the generated photocurrent was measured by a pin-pin photodetector based on a-SiC:H/a-Si:H. This device operates as a visible optical filter with controlled wavelength sensitivity through the use of adequate optical biasing light. Thus it is able to detect different wavelengths which allow the detection of the individual components of the tri-chromatic white LED. This possibility is the basis for the indoor location algorithm. We demonstrate the possibility of decoding four transmission optical channels supplied by two different wavelengths of white LEDs modulated under different bit sequences. The identification of the signals received by the photodetector allows the location identification of the photodetector position and supplies indoor navigation.

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