Simulation results of dynamically reconfigurable broadband photonic access networks (BB photonics)

The integration of wireless and optical networks increases the capacity and mobility as well as decreases costs in the access networks. However, there are nonlinearity and obstacles preventing them from being perfect media. A serious issue for WDM systems is the presence of resonant four wave mixing (FWM) terms, as a result of interactions between different channels. FWM presents a major source of non-linear cross talk since they often fall near or on top of the desired signals. So the best solution is to avoid the FWM generation from early design stages. The effect of four wave mixing (FWM) as one of the influential factors in the WDM for RoF has been studied here using Optisystem. The investigation of FWM effect with different number of channels at various channel spacing has also been done. The simulation results reveal that the less number of users at input cause less FWM but in today’s technology, it is important for the circuit to handle WDM.

Adaptive Scheduling for TCP-Fairness in Wireless Broadband Networks

Wireless Multi-Access Environments and Quality of Service Provisioning ◽

10.4018/978-1-4666-0017-1.ch007 ◽

2011 ◽

pp. 161-186

Author(s):

Balakrishnan K ◽

Ritesh Kumar Kalle ◽

Debabrata Das

Keyword(s):

Access Networks ◽

Adaptive Scheduling ◽

Wireless Access ◽

Wireless Access Networks ◽

Broadband Wireless ◽

Last Mile ◽

Tcp Fairness ◽

Wireless Broadband ◽

Simulation Results ◽

Tcp Throughput

The exponential growth in multimedia traffic (Cisco Visual Networking Index, 2010), predominantly on UDP transport, poses a threat to the TCP’s best effort throughput. This problem is more acute in last mile broadband wireless access networks (Bakshi, Krishna, Vaidya, & Pradhan, 1997). Most scheduling algorithms discuss improving the combined TCP and UDP throughput or improving the TCP throughput without studying the effects of inelastic traffic such as UDP. This chapter furthers the necessity for TCP throughput protection and proposes a novel dynamically adapting Weighted Fair Queue (WFQ) based scheduling mechanism that provides a higher degree of TCP protection. This is accomplished by differentiating between TCP and UDP flows, buffer provisioning for each flow, and prioritizing TCP ACK packets. The simulation results show that the proposed mechanism yields a relative improvement of up to 29% of TCP goodput and 7.5% of aggregate MAC throughput over the mechanism without the proposed improvements.

Energy Efficient Frame Structure for Gigabit Passive Optical Networks

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v6i6.11109 ◽

2016 ◽

Vol 6 (6) ◽

pp. 2971

Author(s):

Rizwan Aslam Butt ◽

Sevia Mahdaliza Idrus ◽

Raja Zahilah Radzi ◽

Kashif Naseer Qureshi

Keyword(s):

Optical Networks ◽

Energy Efficient ◽

Optical Network ◽

Access Networks ◽

Frame Structure ◽

Passive Optical Networks ◽

Information And Communication ◽

Simulation Results ◽

Life On Earth ◽

Additional Hardware

<p>Increasing power consumption in information and communication access networks is one of the major cause of greenhouse gas emissions. These emissions are harmful to life on earth. Passive Optical Networks (PONs) are energy efficient but the broadcast nature of downstream traffic may cause of huge unnecessary processing of frames by the optical network units and result in significant energy wastage. Bi-PON technique tried to solve this problem by changing the XGPON / GPON frame structure to an interleaved pattern but also required additional hardware changings at the optical network units. In this study, we have tried to achieve the same objective by making a few changings in the GPON frame structure without modifying the existing hardware structure. The simulation results show that 25.25% processing energy of an ONU can be saved by incorporating these changes.</p>

Energy Efficient Frame Structure for Gigabit Passive Optical Networks

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v6i6.pp2971-2978 ◽

2016 ◽

Vol 6 (6) ◽

pp. 2971

Author(s):

Rizwan Aslam Butt ◽

Sevia Mahdaliza Idrus ◽

Raja Zahilah Radzi ◽

Kashif Naseer Qureshi

Keyword(s):

Optical Networks ◽

Energy Efficient ◽

Optical Network ◽

Access Networks ◽

Frame Structure ◽

Passive Optical Networks ◽

Information And Communication ◽

Simulation Results ◽

Life On Earth ◽

Additional Hardware

<p>Increasing power consumption in information and communication access networks is one of the major cause of greenhouse gas emissions. These emissions are harmful to life on earth. Passive Optical Networks (PONs) are energy efficient but the broadcast nature of downstream traffic may cause of huge unnecessary processing of frames by the optical network units and result in significant energy wastage. Bi-PON technique tried to solve this problem by changing the XGPON / GPON frame structure to an interleaved pattern but also required additional hardware changings at the optical network units. In this study, we have tried to achieve the same objective by making a few changings in the GPON frame structure without modifying the existing hardware structure. The simulation results show that 25.25% processing energy of an ONU can be saved by incorporating these changes.</p>

Dynamically Reconfigurable NoC for Future Heterogeneous Multi-core Architectures

Dynamic Reconfigurable Network-on-Chip Design ◽

10.4018/978-1-61520-807-4.ch010 ◽

2010 ◽

pp. 256-276

Author(s):

Balal Ahmad ◽

Ali Ahmadinia ◽

Tughrul Arslan

Keyword(s):

Network Interface ◽

Packet Size ◽

Network Delay ◽

Data Intensive ◽

Dynamically Reconfigurable ◽

High Data ◽

Communication Framework ◽

Data Throughput ◽

Channel Bandwidth ◽

Simulation Results

To increase the efficiency of NoCs and to efficiently utilize the available hardware resources, a novel dynamically reconfigurable NoC (drNoC) is proposed in this chapter. Exploiting the notion of hardware reconfigurability, the proposed drNoC reconfigures itself in terms of switching, routing and packet size with the changing communication requirements of the system at run time, thus utilizing the maximum available channel bandwidth. In order to increase the applicability of drNoC, the network interface is designed to support OCP socket standard. This makes drNoC a highly re-useable communication framework, qualifying it as a communication centric platform for high data intensive SoC architectures. Simulation results show a 32% increase in data throughput and 22-35% decrease in network delay when compared with a traditional NoC with fixed parameters.

Efficient Algorithms for Coded Multicasting in Heterogeneous Caching Networks

Entropy ◽

10.3390/e21030324 ◽

2019 ◽

Vol 21 (3) ◽

pp. 324 ◽

Cited By ~ 2

Author(s):

Giuseppe Vettigli ◽

Mingyue Ji ◽

Karthikeyan Shanmugam ◽

Jaime Llorca ◽

Antonia Tulino ◽

...

Keyword(s):

Time Complexity ◽

Storage Capacity ◽

Content Delivery ◽

Access Networks ◽

System Parameters ◽

Content Delivery Networks ◽

Local Graph ◽

Simulation Results ◽

Delivery Networks ◽

Exponential Complexity

Coded multicasting has been shown to be a promising approach to significantly improve the performance of content delivery networks with multiple caches downstream of a common multicast link. However, the schemes that have been shown to achieve order-optimal performance require content items to be partitioned into several packets that grows exponentially with the number of caches, leading to codes of exponential complexity that jeopardize their promising performance benefits. In this paper, we address this crucial performance-complexity tradeoff in a heterogeneous caching network setting, where edge caches with possibly different storage capacity collect multiple content requests that may follow distinct demand distributions. We extend the asymptotic (in the number of packets per file) analysis of shared link caching networks to heterogeneous network settings, and present novel coded multicast schemes, based on local graph coloring, that exhibit polynomial-time complexity in all the system parameters, while preserving the asymptotically proven multiplicative caching gain even for finite file packetization. We further demonstrate that the packetization order (the number of packets each file is split into) can be traded-off with the number of requests collected by each cache, while preserving the same multiplicative caching gain. Simulation results confirm the superiority of the proposed schemes and illustrate the interesting request aggregation vs. packetization order tradeoff within several practical settings. Our results provide a compelling step towards the practical achievability of the promising multiplicative caching gain in next generation access networks.

Dynamically reconfigurable high-efficiency terahertz metasurface holograms

EPJ Applied Metamaterials ◽

10.1051/epjam/2020012 ◽

2021 ◽

Vol 8 ◽

pp. 2

Author(s):

Mengyuan Hu ◽

Zhen Tian

Keyword(s):

Gallium Arsenide ◽

High Efficiency ◽

Polarized Light ◽

Pump Light ◽

Circularly Polarized Light ◽

Circularly Polarized ◽

Time Dynamic ◽

Dynamically Reconfigurable ◽

Dynamic Display ◽

Simulation Results

A reflective, dynamically reconfigurable, high-efficiency metasurface holographic scheme is presented in this paper, which is realized by pumping thin gallium arsenide wafers with a structured femtosecond laser. When the terahertz (THz) passes through the gallium arsenide wafer (GaAs), the pattern carried by the pump light is converted into the complex permittivity of the light carrier density distribution on the gallium arsenide wafer, which modulates the wafer, thereby changing the transmittance of the THz wave. The wavefront of the THz beam is determined by changing the shape and direction of the projected resonator on the DMD by Pancharatnam-Berry (P-B) phase principle. The numerical simulation results show that different holograms can be obtained by dynamically switching the projection on the DMD, and the orthogonal conversion efficiency of circularly polarized light can reach 90%. The holographic scheme proposed in this paper is convenient and fast and may advance the real-time dynamic conversion and dynamic display of holograms.

Analysis of Influence of Optical Electrode Geometry Effects on Manipulation Using Lateral-Field Optoelectronic Tweezers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.194-196.2444 ◽

2011 ◽

Vol 194-196 ◽

pp. 2444-2447

Author(s):

Chun Feng Song ◽

Ke Chen ◽

Zhong Hua Ni

Keyword(s):

Electric Field ◽

Electrode Geometry ◽

Lateral Field ◽

Optoelectronic Tweezers ◽

Dynamically Reconfigurable ◽

Effective Technology ◽

Simulation Results ◽

Floating Electrode ◽

Manipulation Capability ◽

Peak Value

The use of photoconductive film improves the flexibility of dielectrophoretic device and the optoelectronic tweezers provides dynamically reconfigurable optical electrode which provides effective technology in the bio-particles parallel manipulation. In this paper, a circle floating electrode and a castellated shape optical electrode are designed in the lateral-field optoelectronic tweezers. The gradient of the square of the electric field is analyzed as the main parameter. The simulation results show that the floating electrode changes the distribution of the electric field and improves the manipulation capability in the region between the strip electrodes. The castellated shape electrode extends the strip electrode and performs the capability of the traditional physical castellated shape electrode. On the same condition the peak value of x direction of the gradient of the square of the electric field is about 15% smaller than the traditional physical electrode mode because the potential decays in the photoconductive film. To obtain the reconfigurable capability, this shortcoming can be overcome by increasing the applied AC signal voltage.