LOCALIZATION OPTIMIZATION IN WIRELESS SENSOR NETWORKS USING BIO

LOCALIZATION OPTIMIZATION IN WIRELESS SENSOR NETWORKS

USING BIO-INSPIRED ALGORITHMS

Introduction

Localization important for wireless sensor network (WSN)

performance

Bio-inspired algorithms like firefly algorithm (FA) used for

optimization

Proposed hybrid eagle-firefly algorithm for energy-efficient

localization

Firefly Algorithm

Mimics attraction between fireflies based on brightness

Fireflies move towards brighter fireflies for optimization

Used for localization by minimizing distance error

Proposed Hybrid Algorithm

Combines eagle optimization with firefly algorithm

Eagle exploration for global search, firefly for local optimization

Considers received signal strength indication (RSSI)

Results

Hybrid algorithm gives lower MSE than standalone firefly

Localization error reduced by around 15% with hybrid approach

Savings increase with higher node density

Conclusion

Bio-inspired hybrid algorithm enhances localization accuracy

Reduces localization error and optimizes energy consumption

Combines global and local search capabilities for efficiency

Key Highlights

Bio-inspired algorithms suitable for WSN optimization problems

Hybrid algorithm combines benefits of multiple techniques

Energy-efficient localization enables better WSN performance

Results validate superiority of proposed hybrid eagle-firefly

approach

PHOTONIC CRYSTAL BASED ALL-OPTICAL HALF ADDER

Introduction

On-chip photonic integration enables high-speed optical circuits

Photonic crystals allow realizing compact optical logic devices

Proposed photonic crystal based all-optical half adder

Photonic Crystal Design

2D square lattice of silicon rods in air

Line defect waveguide and point cavities introduced

PBG from 1250nm to 1700nm covers telecom wavelengths

Operating Principle

Inputs at Port 1 and Port 2, outputs at Sum and Carry ports

Point cavity resonance conditions control output logic levels

Reference input sets threshold for differentiating logic 0 and 1

Results

Truth table functionally validated through FDTD simulations

High contrast ratio of 7.58dB at Sum port and 9.52dB at Carry port

Fast response time of 1.8ps enables 0.55Tbps operation

Conclusion

Photonic crystal defects enable all-optical logic implementation

Compact half adder demonstrated with high speed and contrast

ratio

Suitable for integrated all-optical information processing circuits

Key Highlights

Photonic bandgap and defects allow controlling light propagation

Resonance conditions in point cavities modulate output signals

Achieves logic functionality along with small footprint and high bit

rate

Essential building block for future integrated optical computing

chips

PHOTONIC CRYSTAL-BASED REVERSIBLE LOGIC GATE

Introduction

Photonic implementations enable high-speed reversible logic gates

Silicon photonics suitable due to compactness, CMOS compatibility

Proposed all-optical reversible swap gate using ring resonator

Ring Resonator Model

Silicon waveguides on SiO2 substrate

Pump and signal inputs control mode conversion

Output at through and drop ports

Operating Principle

Quasi-TE mode input signifies logic '1', Quasi-TM signifies logic '0'

Truth table satisfied by selecting input modes and power

thresholding

Swapping operation demonstrated for different input cases

Results

Functionality verified through FDTD simulations

Ultra-fast switching time of 0.2 ps

Compact single ring resonator swap gate

Conclusion

Photonic ring resonator enables all-optical reversible logic

Speed and simplicity advantageous for optical computing

Swap gate basic building block for reversible networks

Key Highlights

Nanophotonics allows implementing high-speed low-power logic

All-optical realization using photonic crystals and resonators

Compact integrated swap gate demonstrated

Essential for progress towards reversible optical computing

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