empirical study of ann based prediction of resonant frequency and bandwidth of circular slot loaded...
TRANSCRIPT
EMPIRICAL STUDY OF ANN BASED PREDICTION OF
RESONANT FREQUENCY AND BANDWIDTH OF
CIRCULAR SLOT LOADED POLYGON FSS
AUTHOR NAME
• M. PANDA
• MD RABIUL HOSSAIN
• MD EHTESHAM HUSSAIN
• SAMRIDDHA SAMANTA
• RUBABA RAHMAN
Presented byRUBABA RAHMAN
OUTLINE What is FSS
Elements of FSS Design
Types of FSS
Applications of FSS.
Work Done By The Candidate
Conclusions
WHAT IS FREQUENCY SELECTIVE SURFACE ???
A frequency-selective surface (FSS) is any thin, repetitive surface designed to reflect, transmit or absorb electromagnetic fields based on frequency. In this sense, an FSS is a type of optical filter or metal-mesh optical filters in which the filtering is accomplished by virtue of the regular, periodic pattern on the surface of the FSS.
ELEMENTS OF FSS DESIGN
Element Geometries:Patch-type elements-capacitive effect.Aperture-type element-Inductance Effect.
PATCH-TYPE ELEMENTS
The patch-array produces a capacitive response, Band Stop Filter
APERTURE-TYPE ELEMENT
Array of slots is inductive- Band Pass filter
TYPES OF FSSFSS (Based on shapes by MUNK,[1])– 4 Classes.
1. The center connected or N-poles
2. The loop Types
3. Solid interiors or plate types
4.Combinations of 1,2,3
APPLICATIONS OF FREQUENCY SELECTIVE SURFACES ..• Frequency selective surfaces have been most commonly used in
the radio frequency region of the electromagnetic spectrum• use in applications as diverse as the aforementioned microwave
oven, antenna radomes and modern metamaterials.• Sometimes frequency selective surfaces are referred to simply as
periodic surfaces and are a 2-dimensional analog of the new periodic volumes known as photonic crystals.
ARTIFICIAL NEURAL NETWORK (ANN)
Artificial Neural Networks (ANNs) are a family of models inspired by biological neural network i.e. the central nervous system of animals, in particular the brain and are used to estimate or approximate functions that can depend on a large number of inputs and are generally unknown. Artificial neural networks are generally presented as systems of interconnected neurons which exchange messages between each other. The connections have numeric weights that can be tuned based on experience, making neural nets adaptive to inputs and capable of learning.
PROPOSED STRUCTURE OF FSS
The geometry of the single layer FSS unit cell structure shown in Fig which consists of polygon with centrally circular slot loaded. The dimension of unit cell structure is clearly mentioned in the said figure. For x, y direction periodicity the length is 11mm & 16mm respectively. The unit cells are placed in repeated structure in 2D Array form
3 mm
10 mm3
mm
12 m
m
11 mm
16 m
m
SIMULATION RESULT USING ANSOFT
Computer based extensive numerical method is used for designing the parameter of FSS by using different commercial software. Numerical methods are Finite Element Method (FEM), Method of Moment (MOM), Finite Difference Time Domain (FDTD) method etc. For extensive simulation ANSOFT simulation tool is adopted here.
BAND WIDTH VARIATION FOR DIFFERENT Y DIRECTION PERIODICITY
RESONANT FREQUENCY FOR DIFFERENT Y DIRECTION PERIODICITY
ARTIFICIAL ANN FOR PREDICTION OF BW AND RF
Back Propagation (BP) is best on MLN perception. Four layer architecture is used here. One input layer, one output layer and two hidden layer is used for the proposed ANN model. For input layer of ANN model the periodicity in x-direction and y-direction are taken. The output of ANN model is the bandwidth and resonating frequency.
PROPOSE ANN MODEL FOR ESTIMATION OF BAND WIDTH AND RESONANT FREQUENCY
DATA SEQUENCE FOR ANNSl no. Periodi
city in x-
direction
(mm)
Periodicity in
y-directio
n(mm)
1 11 18.5
2 11.5 17
3 12.5 17
4 13.5 18
5 14.5 19.5
Sl No. ANSOFT simulation B.W (GHz)
ANNB.W
(GHz)
1 4.63 4.75
2 5.49 5.38
3 5.28 5.4
4 4.38 4.28
5 3.53 3.66
Sl No. ANSOFT
Simulation RF (GHz)
ANNRF(GHz
)
1 10.35 10.43
2 10.17 10.27
3 9.98 10.1
4 9.88 9.76
5 9.62 9.57
INPUT Output for BW Output for RF
CONCLUSION • All results are quite satisfactory. • Results obtained by proposed ANN structure are compared with ANSOFT
simulation tool results. • In both cases result are quite identical and error value is in acceptance range. • For further future study authors intend to take new model with solid or slit
loaded structure with different dimensions.• Apart from Neural Network authors concentrate on different types of soft
computing tool like PSO,GA, ant colony optimization.
THANK YOU