IJERD (www.ijerd.com) International Journal of Engineering Research and Development IJERD : hard copy of journal, Call for Papers 2012, publishing of journal, journal of science and technology, research paper publishing, where to publish research paper,
The document describes modifications made to a log periodic dipole antenna (LPDA) to make it more portable while maintaining performance. Specifically:
- The original LPDA had a boom length of 5.5 meters, which was reduced to 3.11 meters to improve portability.
- 38 elements were used on two booms to cover frequencies from 45MHz to 1000MHz. Plastic insulation and a spacing factor of 0.08 were used.
- The antenna was connected to a CALLISTO spectrometer via coaxial cable to convert radio signals for detection and measurement of solar bursts.
- Initial results showed the modified compact LPDA operated successfully while maintaining the desired frequency range and directivity.
http://www.axis.com/
When an image is being captured by a network camera, light passes through the lens and falls on the
image sensor. The image sensor consists of picture elements, also called pixels, that register the amount
of light that falls on them. They convert the received amount of light into a corresponding number of
electrons. The stronger the light, the more electrons are generated. The electrons are converted into
voltage and then transformed into numbers by means of an A/D-converter. The signal constituted by the
numbers is processed by electronic circuits inside the camera.
http://www.axis.com/
When an image is being captured by a network camera, light passes through the lens and falls on the
image sensor. The image sensor consists of picture elements, also called pixels, that register the amount
of light that falls on them. They convert the received amount of light into a corresponding number of
electrons. The stronger the light, the more electrons are generated. The electrons are converted into
voltage and then transformed into numbers by means of an A/D-converter. The signal constituted by the
numbers is processed by electronic circuits inside the camera.
This is the image sensing technology base pwerpoint presentation which highlights the basics of image sensing...
Image sensing is a technology of recognising a image or comparing a image or taking a image...
Extraction of Ephemeris file from Matlab SDRAsimKhan367
Ephemeris is the Satellite Position parameters in space of single Satellite ,the given doc is about extracting an Ephemeris file for all given PRN(pseudo random number of sat) from Matlab SDR (software Defined radio) code
for SDR Matlab code :https://github.com/kristianpaul/SoftGNSS
and for Data : http://downloads.qi-hardware.com/people/kristianpaul/GNSS_signal_records.tar.gz
but the results will be different for different data ,
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, - 37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, - 37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar
communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions.
The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz)
with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64
VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -
37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array
elements are feed using a direct feeding technique. This array antenna is suitable developed for use in
radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
This is the image sensing technology base pwerpoint presentation which highlights the basics of image sensing...
Image sensing is a technology of recognising a image or comparing a image or taking a image...
Similar to IJERD (www.ijerd.com) International Journal of Engineering Research and Development IJERD : hard copy of journal, Call for Papers 2012, publishing of journal, journal of science and technology, research paper publishing, where to publish research paper,
Extraction of Ephemeris file from Matlab SDRAsimKhan367
Ephemeris is the Satellite Position parameters in space of single Satellite ,the given doc is about extracting an Ephemeris file for all given PRN(pseudo random number of sat) from Matlab SDR (software Defined radio) code
for SDR Matlab code :https://github.com/kristianpaul/SoftGNSS
and for Data : http://downloads.qi-hardware.com/people/kristianpaul/GNSS_signal_records.tar.gz
but the results will be different for different data ,
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, - 37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, - 37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar
communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions.
The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz)
with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64
VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -
37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array
elements are feed using a direct feeding technique. This array antenna is suitable developed for use in
radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
ARRAY FACTOR IN CURVED MICROSTRIPLINE ARRAY ANTENNA FOR RADAR COMMUNICATION S...jantjournal
This paper presents the designed of varians array in curved microstripline antenna for radar communication. The antenna geometry comprises of three varians in matrics 2x2, 2x4 and 4x4 dimensions. The several array operates in C-Band frequencies (4GHz – 8GHz) and X-Band frequencies (8GHz-12GHz) with a 1.82 VSWR, -18.72dB Return loss, 0.29 reflection coefficient, and 5.8dB gain for 2x2 array, 1.64 VSWR, -16.17dB Return loss, 0.24 reflection coefficient, and 5.4dB gain for 2x4 array, 1.04 VSWR, -37.70dB Return loss, 0.19 reflection coefficient, and 7.6dB gain for 4x4 array. All of the varians in array elements are feed using a direct feeding technique. This array antenna is suitable developed for use in radar communication systems.
Similar to IJERD (www.ijerd.com) International Journal of Engineering Research and Development IJERD : hard copy of journal, Call for Papers 2012, publishing of journal, journal of science and technology, research paper publishing, where to publish research paper, (20)
A Novel Method for Prevention of Bandwidth Distributed Denial of Service AttacksIJERD Editor
Distributed Denial of Service (DDoS) Attacks became a massive threat to the Internet. Traditional
Architecture of internet is vulnerable to the attacks like DDoS. Attacker primarily acquire his army of Zombies,
then that army will be instructed by the Attacker that when to start an attack and on whom the attack should be
done. In this paper, different techniques which are used to perform DDoS Attacks, Tools that were used to
perform Attacks and Countermeasures in order to detect the attackers and eliminate the Bandwidth Distributed
Denial of Service attacks (B-DDoS) are reviewed. DDoS Attacks were done by using various Flooding
techniques which are used in DDoS attack.
The main purpose of this paper is to design an architecture which can reduce the Bandwidth
Distributed Denial of service Attack and make the victim site or server available for the normal users by
eliminating the zombie machines. Our Primary focus of this paper is to dispute how normal machines are
turning into zombies (Bots), how attack is been initiated, DDoS attack procedure and how an organization can
save their server from being a DDoS victim. In order to present this we implemented a simulated environment
with Cisco switches, Routers, Firewall, some virtual machines and some Attack tools to display a real DDoS
attack. By using Time scheduling, Resource Limiting, System log, Access Control List and some Modular
policy Framework we stopped the attack and identified the Attacker (Bot) machines
Hearing loss is one of the most common human impairments. It is estimated that by year 2015 more
than 700 million people will suffer mild deafness. Most can be helped by hearing aid devices depending on the
severity of their hearing loss. This paper describes the implementation and characterization details of a dual
channel transmitter front end (TFE) for digital hearing aid (DHA) applications that use novel micro
electromechanical- systems (MEMS) audio transducers and ultra-low power-scalable analog-to-digital
converters (ADCs), which enable a very-low form factor, energy-efficient implementation for next-generation
DHA. The contribution of the design is the implementation of the dual channel MEMS microphones and powerscalable
ADC system.
Influence of tensile behaviour of slab on the structural Behaviour of shear c...IJERD Editor
-A composite beam is composed of a steel beam and a slab connected by means of shear connectors
like studs installed on the top flange of the steel beam to form a structure behaving monolithically. This study
analyzes the effects of the tensile behavior of the slab on the structural behavior of the shear connection like slip
stiffness and maximum shear force in composite beams subjected to hogging moment. The results show that the
shear studs located in the crack-concentration zones due to large hogging moments sustain significantly smaller
shear force and slip stiffness than the other zones. Moreover, the reduction of the slip stiffness in the shear
connection appears also to be closely related to the change in the tensile strain of rebar according to the increase
of the load. Further experimental and analytical studies shall be conducted considering variables such as the
reinforcement ratio and the arrangement of shear connectors to achieve efficient design of the shear connection
in composite beams subjected to hogging moment.
Gold prospecting using Remote Sensing ‘A case study of Sudan’IJERD Editor
Gold has been extracted from northeast Africa for more than 5000 years, and this may be the first
place where the metal was extracted. The Arabian-Nubian Shield (ANS) is an exposure of Precambrian
crystalline rocks on the flanks of the Red Sea. The crystalline rocks are mostly Neoproterozoic in age. ANS
includes the nations of Israel, Jordan. Egypt, Saudi Arabia, Sudan, Eritrea, Ethiopia, Yemen, and Somalia.
Arabian Nubian Shield Consists of juvenile continental crest that formed between 900 550 Ma, when intra
oceanic arc welded together along ophiolite decorated arc. Primary Au mineralization probably developed in
association with the growth of intra oceanic arc and evolution of back arc. Multiple episodes of deformation
have obscured the primary metallogenic setting, but at least some of the deposits preserve evidence that they
originate as sea floor massive sulphide deposits.
The Red Sea Hills Region is a vast span of rugged, harsh and inhospitable sector of the Earth with
inimical moon-like terrain, nevertheless since ancient times it is famed to be an abode of gold and was a major
source of wealth for the Pharaohs of ancient Egypt. The Pharaohs old workings have been periodically
rediscovered through time. Recent endeavours by the Geological Research Authority of Sudan led to the
discovery of a score of occurrences with gold and massive sulphide mineralizations. In the nineties of the
previous century the Geological Research Authority of Sudan (GRAS) in cooperation with BRGM utilized
satellite data of Landsat TM using spectral ratio technique to map possible mineralized zones in the Red Sea
Hills of Sudan. The outcome of the study mapped a gossan type gold mineralization. Band ratio technique was
applied to Arbaat area and a signature of alteration zone was detected. The alteration zones are commonly
associated with mineralization. The alteration zones are commonly associated with mineralization. A filed check
confirmed the existence of stock work of gold bearing quartz in the alteration zone. Another type of gold
mineralization that was discovered using remote sensing is the gold associated with metachert in the Atmur
Desert.
Reducing Corrosion Rate by Welding DesignIJERD Editor
The paper addresses the importance of welding design to prevent corrosion at steel. Welding is
used to join pipe, profiles at bridges, spindle, and a lot more part of engineering construction. The
problems happened associated with welding are common issues in these fields, especially corrosion.
Corrosion can be reduced with many methods, they are painting, controlling humidity, and also good
welding design. In the research, it can be found that reducing residual stress on the welding can be
solved in corrosion rate reduction problem.
Preheating on 500oC and 600oC give better condition to reduce corosion rate than condition after
preheating 400oC. For all welding groove type, material with 500oC and 600oC preheating after 14 days
corrosion test is 0,5%-0,69% lost. Material with 400oC preheating after 14 days corrosion test is 0,57%-0,76%
lost.
Welding groove also influence corrosion rate. X and V type welding groove give better condition to reduce
corrosion rate than use 1/2V and 1/2 X welding groove. After 14 days corrosion test, the samples with
X welding groove type is 0,5%-0,57% lost. The samples with V welding groove after 14 days corrosion test is
0,51%-0,59% lost. The samples with 1/2V and 1/2X welding groove after 14 days corrosion test is 0,58%-
0,71% lost.
Router 1X3 – RTL Design and VerificationIJERD Editor
Routing is the process of moving a packet of data from source to destination and enables messages
to pass from one computer to another and eventually reach the target machine. A router is a networking device
that forwards data packets between computer networks. It is connected to two or more data lines from different
networks (as opposed to a network switch, which connects data lines from one single network). This paper,
mainly emphasizes upon the study of router device, it‟s top level architecture, and how various sub-modules of
router i.e. Register, FIFO, FSM and Synchronizer are synthesized, and simulated and finally connected to its top
module.
Active Power Exchange in Distributed Power-Flow Controller (DPFC) At Third Ha...IJERD Editor
This paper presents a component within the flexible ac-transmission system (FACTS) family, called
distributed power-flow controller (DPFC). The DPFC is derived from the unified power-flow controller (UPFC)
with an eliminated common dc link. The DPFC has the same control capabilities as the UPFC, which comprise
the adjustment of the line impedance, the transmission angle, and the bus voltage. The active power exchange
between the shunt and series converters, which is through the common dc link in the UPFC, is now through the
transmission lines at the third-harmonic frequency. DPFC multiple small-size single-phase converters which
reduces the cost of equipment, no voltage isolation between phases, increases redundancy and there by
reliability increases. The principle and analysis of the DPFC are presented in this paper and the corresponding
simulation results that are carried out on a scaled prototype are also shown.
Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVRIJERD Editor
Power quality has been an issue that is becoming increasingly pivotal in industrial electricity
consumers point of view in recent times. Modern industries employ Sensitive power electronic equipments,
control devices and non-linear loads as part of automated processes to increase energy efficiency and
productivity. Voltage disturbances are the most common power quality problem due to this the use of a large
numbers of sophisticated and sensitive electronic equipment in industrial systems is increased. This paper
discusses the design and simulation of dynamic voltage restorer for improvement of power quality and
reduce the harmonics distortion of sensitive loads. Power quality problem is occurring at non-standard
voltage, current and frequency. Electronic devices are very sensitive loads. In power system voltage sag,
swell, flicker and harmonics are some of the problem to the sensitive load. The compensation capability
of a DVR depends primarily on the maximum voltage injection ability and the amount of stored
energy available within the restorer. This device is connected in series with the distribution feeder at
medium voltage. A fuzzy logic control is used to produce the gate pulses for control circuit of DVR and the
circuit is simulated by using MATLAB/SIMULINK software.
Study on the Fused Deposition Modelling In Additive ManufacturingIJERD Editor
Additive manufacturing process, also popularly known as 3-D printing, is a process where a product
is created in a succession of layers. It is based on a novel materials incremental manufacturing philosophy.
Unlike conventional manufacturing processes where material is removed from a given work price to derive the
final shape of a product, 3-D printing develops the product from scratch thus obviating the necessity to cut away
materials. This prevents wastage of raw materials. Commonly used raw materials for the process are ABS
plastic, PLA and nylon. Recently the use of gold, bronze and wood has also been implemented. The complexity
factor of this process is 0% as in any object of any shape and size can be manufactured.
Spyware triggering system by particular string valueIJERD Editor
This computer programme can be used for good and bad purpose in hacking or in any general
purpose. We can say it is next step for hacking techniques such as keylogger and spyware. Once in this system if
user or hacker store particular string as a input after that software continually compare typing activity of user
with that stored string and if it is match then launch spyware programme.
A Blind Steganalysis on JPEG Gray Level Image Based on Statistical Features a...IJERD Editor
This paper presents a blind steganalysis technique to effectively attack the JPEG steganographic
schemes i.e. Jsteg, F5, Outguess and DWT Based. The proposed method exploits the correlations between
block-DCTcoefficients from intra-block and inter-block relation and the statistical moments of characteristic
functions of the test image is selected as features. The features are extracted from the BDCT JPEG 2-array.
Support Vector Machine with cross-validation is implemented for the classification.The proposed scheme gives
improved outcome in attacking.
Secure Image Transmission for Cloud Storage System Using Hybrid SchemeIJERD Editor
- Data over the cloud is transferred or transmitted between servers and users. Privacy of that
data is very important as it belongs to personal information. If data get hacked by the hacker, can be
used to defame a person’s social data. Sometimes delay are held during data transmission. i.e. Mobile
communication, bandwidth is low. Hence compression algorithms are proposed for fast and efficient
transmission, encryption is used for security purposes and blurring is used by providing additional
layers of security. These algorithms are hybridized for having a robust and efficient security and
transmission over cloud storage system.
Application of Buckley-Leverett Equation in Modeling the Radius of Invasion i...IJERD Editor
A thorough review of existing literature indicates that the Buckley-Leverett equation only analyzes
waterflood practices directly without any adjustments on real reservoir scenarios. By doing so, quite a number
of errors are introduced into these analyses. Also, for most waterflood scenarios, a radial investigation is more
appropriate than a simplified linear system. This study investigates the adoption of the Buckley-Leverett
equation to estimate the radius invasion of the displacing fluid during waterflooding. The model is also adopted
for a Microbial flood and a comparative analysis is conducted for both waterflooding and microbial flooding.
Results shown from the analysis doesn’t only records a success in determining the radial distance of the leading
edge of water during the flooding process, but also gives a clearer understanding of the applicability of
microbes to enhance oil production through in-situ production of bio-products like bio surfactans, biogenic
gases, bio acids etc.
Gesture Gaming on the World Wide Web Using an Ordinary Web CameraIJERD Editor
- Gesture gaming is a method by which users having a laptop/pc/x-box play games using natural or
bodily gestures. This paper presents a way of playing free flash games on the internet using an ordinary webcam
with the help of open source technologies. Emphasis in human activity recognition is given on the pose
estimation and the consistency in the pose of the player. These are estimated with the help of an ordinary web
camera having different resolutions from VGA to 20mps. Our work involved giving a 10 second documentary to
the user on how to play a particular game using gestures and what are the various kinds of gestures that can be
performed in front of the system. The initial inputs of the RGB values for the gesture component is obtained by
instructing the user to place his component in a red box in about 10 seconds after the short documentary before
the game is finished. Later the system opens the concerned game on the internet on popular flash game sites like
miniclip, games arcade, GameStop etc and loads the game clicking at various places and brings the state to a
place where the user is to perform only gestures to start playing the game. At any point of time the user can call
off the game by hitting the esc key and the program will release all of the controls and return to the desktop. It
was noted that the results obtained using an ordinary webcam matched that of the Kinect and the users could
relive the gaming experience of the free flash games on the net. Therefore effective in game advertising could
also be achieved thus resulting in a disruptive growth to the advertising firms.
Hardware Analysis of Resonant Frequency Converter Using Isolated Circuits And...IJERD Editor
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LCC resonant converter it is associated with a disadvantage that, though it has two resonant frequencies, the
lower resonant frequency is in ZCS region [5]. For this application, we are not able to design the converter
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series resonant tank of Lr and Cr converter acts very similar to Series Resonant Converter. The benefit of LLC
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exclusive transformer supply[3]. The IGBT’s are fired using the appropriate signal using the previous boards
and hence at last a high frequency rectifier ckt with a filtering capacitor is used to get an exact dc
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IJERD (www.ijerd.com) International Journal of Engineering Research and Development IJERD : hard copy of journal, Call for Papers 2012, publishing of journal, journal of science and technology, research paper publishing, where to publish research paper,
1. International Journal of Engineering Research and Development
e-ISSN: 2278-067X, p-ISSN: 2278-800X, www.ijerd.com
Volume 3, Issue 3 (August 2012), PP. 36-39
Modification and Performance of Log Periodic Dipole Antenna
Z.S.Hamidi1, Abidin Z.Z2, Ibrahim Z.A.3, N.N.M. Shariff4, C. Monstein5
1,2,3,4
Faculty of Science, University Malaya, Kuala Lumpur, Malaysia
1
Faculty of Applied Sciences, University Teknologi MARA, UiTM S.Alam Selangor, Malaysia
5
Institute of Astronomy, ETH Zurich, Switzerland
Abstract––Technological advances and developments in solar activities, particularly in solar radio bursts, have created a
demand of constructing log periodic dipole antenna (LPDA) to monitor this phenomenon in radio region. In this paper,
we make an effort in designing a portable LPDA that suitable with the criteria, specification and practical enough
although is the boom length size of the antenna is 3.11meter. This initiative is to modify so that it will be more portable
and established enough. We choose value of 0.08 spacing factor τ= 0.8 as a directivity of antenna. The performance of
this antenna will also be discussed.
Index Terms––Log Periodic Dipole Antenna (LPDA), signal detection
I. INTRODUCTION
Technological advances and developments in solar activities, particularly in solar radio bursts, have created a
demand of constructing log periodic dipole antenna (LPDA) to monitor this phenomenon in radio region. In principle,
antennas can be used to transmit or receive electromagnetic waves. The properties in both cases are the same due to the
principle of reciprocity. Among the types of antennas, LPDA have attracted much attention lately due to the broadband
frequencies. During recent years, logarithmically periodic antennas have been widely used due to their frequency response
characteristics, simplicity of design and directivity [8]. It also part of ISWI (International Space Weather Initiative) project
in order to monitoring the solar activity 24h/7d coverage of solar observations in state of support develop countries
participate internationally with a latest technologies of instrument [1]. In our work, we need to construct an antenna to
monitor solar burst in radio region. These bursts can best be distinguished in spectrometer, as demonstrated already. In the
meter wavelength range, 5 types of radio emissions are distinguished and at decimeter wavelengths there is a similar number
[2, 3]. The Log Periodic Dipole Antenna (LPDA) plays an important role in the modern communication and radar system
[7]. Development of LPDA has started since 1961 initiated by Isbell [6]. Later, Carrel analyzed the LPDA mathematically
and computed its radiation pattern, input impedance, etc., using a digital computer [9]. It must be sensitive to a broad
frequency range and angular distribution of the incident radio pulse. On the other hand, it plays an important role in
handling the noise issue and thus is essential to detect preferably pure signals. One main criteria that make LPDA become
more relevant is due to it sensitivity that possible to detect signal of the Sun. Moreover, it also economical and practical to
be implements.
Our first construction of LPDA has successfully been setup at National Space Centre, Banting on 21st February
2012. This antenna focused in 45 MHz till 870 MHz. although we could obtain a good data of solar burst; there is still
improvement that needs to be done. Due to long boom length, approximately 5.5 meter, its make antenna become not
practical for portable purpose. In addition, we still need to improvised by reduce the length of the cable which been quite
long to the detector. Our previous antenna also not covered the range below than 80 MHz where this situation will limit the
detection of low frequency of solar. Since radio waves at frequencies < 150 MHz from the Sun originate primarily in its
corona, observations of polarized solar radio emission can be used to derive information about the magnetic field in the
corona. The lightning protection of the antenna also should be concerned by used other material at the top of the antenna.
Low antenna impedance problem can be olve by designing dipole and folded dipole antennas because they shows higher
antenna impedance than monopole antenna but planar diversity folded dipole and M-slot folded patch antenna has lower
gain in associated application [5].
For the further treatment of the received data, a precise knowledge of the antenna characteristics is necessary. A
detailed characterization of the mentioned logarithmic periodic dipole antennas is one major objective. Therefore, we plan to
modify the antenna by considering the same range of frequency but can be used portably. We choose a range from 45MHz
till 1000 MHz but the length of the antenna reduce to 3.11meter. In this paper, we make an effort in designing a portable
LPDA that suitable with the criteria, specification and practical enough to observe the solar activities daily.
II. SPECIFICATION OF THE LOG PERIODIC DIPLOLE ANTENNA (LPDA)
Here, we summarized the various aspects of the antenna system, digital hardware, the data acquisition and receiver
front is presented in this section. Figure 1 showed the schematic diagram of LPDA. A total of 38 elements will be that
represent specific frequency will be constructed for two (2) boom. We choose to use a plastic material as an insulator. The
diameter of the insulator is 30mm x 18mm. This size is better enough compared to our previous antenna which is 10 x10 mm
only. We also choose value of 0.08 spacing factor τ= 0.8 as a directivity of antenna. This log periodic dipole antenna
36
2. Modification and Performance of Log Periodic Dipole Antenna
directly control via low loss coaxial cable type RG8 to the CALLISTO spectrometer. The Compact Astronomical Low-cost
Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) has been described in detail by
Benz et al. [2,3]. CALLISTO spectrometer will convert the high-frequency electromagnetic signals into a form convenient
for detecting and measuring the incoming radio emission. With large instantaneous bandwidths and high spectral
resolutions, these instruments will provide increased imaging sensitivity and enable detailed measurements of the dynamic
solar burst. We also used the preamplifier ~20dB for amplification purpose. As a part of data acquisition, CALLISTO
software and RAPP JAVA Viewer will be used. We also can use IDL program to analyze the data. The specification of the
antenna is described in Table 1.
Fig 1. Schematic diagram of LPDA
37
3. Modification and Performance of Log Periodic Dipole Antenna
Table I : Overall Performance For The Car Sequence
No of elements L R d
1 3.96 3.17 0.64
2 3.17 2.54 0.50
3 2.54 2.03 0.40
4 2.03 1.62 0.32
5 1.62 1.29 0.26
6 1.29 1.04 0.21
7 1.04 0.83 0.16
8 0.83 0.66 0.13
9 0.66 0.53 0.11
10 0.53 0.43 0.09
11 0.43 0.34 0.07
12 0.34 0.27 0.05
13 0.27 0.21 0.04
14 0.21 0.17 0.03
15 0.17 0.14 0.02
16 0.14 0.11 0.21
17 0.11 0.09 0.017
18 0.09 0.07 0.014
19 0.07 0.06 0.011
III. RESULTS AND DISCUSSION
The log periodic dipole antenna for the range 45–1000 MHz (Low Frequency Broad Band) is a stationary inverted
V dipole, on the east-west vertical plane. Each leg has a length of 3.1 m with maximum a width of 1 m. At present this
LPDA has been operated at Physics Department University of Malaya located at 3°7′51″N 101°40′10″E. For calibration
purpose, this antenna is disconnected from the system and a white noise generator (constant,T = 104 K) is connected. The
duration of the calibration is about 1 min and the signal is recorded. The main purpose to get this signal is used to recognize
the whole system behavior and to calibrate it. After the end of the calibration the antenna is connected again to the system.
The values of scale factor (τ), subtended angle (α), and spacing factor (σ) are chosen so that the resulting gains can be
compared to the constant directivity contours for LPDAs by Carrel [4].
Table II : Comparison of LPDA modification with the previous antenna
Frequency range 80 MHz to 870 45 MHz to
MHz 1000 MHz
Polarization linear linear
Input impedance 50 Ω (unbalanced) 50 Ω
(unbalanced)
Standing wave 1 ≤2 1 ≤2
ratio (VSWR)
Spacing factor 0.14 0.08
Gain 6.5 dBi 10 dBi
RF connector N connector N connector
Antenna length 5.45 m 3.11 m
Max. antenna 1.98 m 1.98 m
width
Weight 6 kg 4.2 kg
Lightning Yes Yes
protection
The antenna is mounted horizontally on a steerable azimuth/elevation tower and controlled by the computer to
automatically point the sun during the day time. Beside the established detection techniques, the construction of antenna also
needs to be improved. Logarithmic periodic dipole antenna (LPDA) was designed to precisely match the environmental
requirements. The used LPDA play a key role for the successful detection of solar burst as they provide the sensitive
component of the radio detector. The Callisto spectrometer e-C07 having a detector sensitivity of 25mV/dB including
control cables and rf adapters was supplied by ETH Zurich. Meanwhile, the frequency range of CALLISTO spectrometer
ranges from 45MHz to 870MHz in three (3) sub bands. The channel resolution is 62.5 kHz, while the radiometric bandwidth
is about 300 kHz. The sampling time is exactly 1.25msec per frequency-pixel while the integration time is about 1msec. The
frequency in the output data is expressed in MHz and the detector output is expressed in millivolts. To transfer signals in the
38
4. Modification and Performance of Log Periodic Dipole Antenna
radio frequency regime (1-100 MHz) preferably lossless, special cables are needed. We used RG-8 cable for outdoor
purpose. At this location an additional measurement was taken when applying a 50Ω resistor to the antenna terminal as a
reference level to evaluate the power level in dB above this broad- band load (a termination resistor at ambient temperature
in the order of 300Kelvin). Both are stored in a simple ASCII which can be analyzed with any spread sheet like IDL, Math-
CAD or EXCEL. By improving the method of construction, we will achieve a deeper understanding of the mode of
operation of LPDAs by measurements of the electrical transactions within the antenna structure and of single components of
LPDAs. Our next plan is to attempt different test setups will be used to benchmark both, the electrical and mechanical
performance of the LPDA concerning low region of radio frequency.
IV. CONCLUSION
Concerning the objective to expand the low limit of the receiving frequencies is to investigate more detection of
solar burst to very low frequencies; it is become possible with the construction of LPDA. It could not be denied that the
radio detection of solar activities in radio region makes various demands on the used antennas. We also managed to
improvise the value of gain with 10 dB compared to the previous one 5.71 dB. We will motivate the electrical and
mechanical conception of the used LPDAs as a consequence of a precise adjustment of the antenna properties to the
demands of radio detection for the next construction. The daily operation is fully automated: receiving universal time from a
GPS, pointing the antenna to the sun, system calibration, starting and stopping the observations at preset times, data
acquisition, and archiving on database. This antenna can be used either permanently or portably to study the onset and
evolution of solar radio bursts and associated solar flare phenomena. Up to date, we have shown the improvement of the
LPDA construction. Our next task is to monitor the Sun activities, compare with the other sites and make a solar burst model
for the long term project.
ACKNOWLEDGMENT
We express our sincere thanks to University Malaya, Universiti Teknologi MARA, National Agency Space of
Malaysia (ANGKASA) and National Space Centre for the collaborations of e-CALLISTO. The development, production and
distribution of CALLISTO spectrometers it supported by ETH engineer. The author also would like to thanks to C. Monstein
from Switzerland and Prof Dr Zainol Abidin Ibrahim for the technical part of advice. This work was partially supported by
the Excellence Fund UiTM and PPP UM PV071/2011B grants. This project is an initiative work of the International of
Space Weather Initiative (ISWI) program.
REFERENCES
[1]. A.O. Benz, Plasma Astrophysics, 2nd edn. (Springer, Dordrecht, 2002).
[2]. Arnold O. Benz, Christian Monstein and Hansueli Meyer CALLISTO, A New Concept for Solar Radio
Spectrometers, Kluwer Academic Publishers, The Netherlands, 2004.
[3]. Arnold O. Benz, Christian Monstein and Hansueli Meyer CALLISTO, A New Concept for Solar Radio
Spectrometers, Kluwer Academic Publishers, The Netherlands, 2004.
[4]. Carr J .: „Some variations in log-periodic antenna structures‟, IRE Trans. Antennas Propag., 1961, 9, (2), pp.
229–230
[5]. Constantine A.B.: „Antenna theory: analysis and design [M]‟ (Wiley-Interscience, 2005)
[6]. D.E.Isbell, “ Log-periodic dipole arrays,” IRE Trans. Antenna Propagate., Vol.AP-8, pp.260-267, May 1960.
[7]. G.H. Zhai, W. Hong, K. Wu and Z.Q. Kuai, “Wideband substrate integrated printed log-periodic dipole array
antenna”, IET Microw. Antennas Propag., Vol. 4, Iss. 7, pp. 899–905, 2010.
[8]. Mittra., Jones K.E.: „Theoretical brillouin (k 2 b) diagrams for monopole and dipole arrays and their applications
to log-periodic antennas‟, IEEE Trans. Antennas Propag., 1964, 51, (3), pp. 533–540
[9]. R.L.Carrel, “ The design of log periodic dipole antennas” in 1961 IRE Conv.Rec., Vol 1, pp 61-75.
39