NOISE REDUCTION USING SHIELDING

ABSTRACT

With the advent of technology a lot of equipment use electromagnetic signals for their operation. The devices intentionally or unintentionally interfere with the operation of other circuits and effect their performance. For the proper functioning of the devices this interference needs to be avoided at least suppressed. With the advent of technology electronic/electrical systems are forced to work in the close proximity. So the effects of EMI are highly influencing the circuit operations.

We studied vigorously about the electromagnetic interference and its nature. Also the methods of suppressing EMI. We laid emphasis on shielding method of suppressing EMI. At high frequency shielding is effective method. The shield must completely enclose the electronics and must have no penetrations such as holes, seams, slots or cables.

In this paper we studied the shielding effectiveness of different metals like Copper, Aluminium, Gold, Lead and Silver, for various thicknesses. The Variation of Shielding Effectiveness with respect to the frequency are plotted and results are presented in the table. The shielding effectiveness is estimated up to 10MHz.

Table 4.1 Relative Conductivity for Metals

S.No.	Metals	Relative conductivity
1.	Aluminium	62
2.	Gold	71
3.	Copper	100
4.	Silver	105
5.	Lead	8
6.	Mercury	2
7.	Zinc	30

Table 4.2 Relative permeability for Metals

S.No	Metals	Relative Permeability
1.	Aluminium	1
2.	Gold	1
3.	Copper	1
4.	Lead	1
5.	Silver	1
6.	Mercury	1
7.	Zinc	1

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authors:

CH.SURYA PRABHA (Btech RVR&JC COLLEGE OF ENGG.)

G.SRINATH (Btech RVR&JC COLLEGE OF ENGG.)

A.L.S DURGA (Btech RVR&JC COLLEGE OF ENGG.)

B.SURESH (Btech RVR&JC COLLEGE OF ENGG.)

B.JILA (Btech RVR&JC COLLEGE OF ENGG.)

I sincerely thank authors,the students of "RVR&JC COLLEGE OF ENGG"

for their great support.

my special thanks to v.v.m.m.rao

TO DOWNLOAD FULL PROJECT REPORT CLICK HERE

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GENERATION OF CRYPTOGRAPHIC KEYS FROM FACIAL FEATURES

ABSTRACT

The main Objective of the project is to generate a biometric based cryptographic key from facial features. Existing asymmetric encryption algorithms require the storage of the secret private key. Stored keys are often protected by poorly selected user passwords that can either be guessed or obtained through brute force attacks. Combining biometrics with cryptography is seen as a possible solution but any biometric cryptosystem must be able to overcome small variations present between different acquisitions of the same biometric in order to produce consistent keys. A new method which uses entropy based feature extraction process coupled with Reed-Solomon error correcting codes that can generate deterministic bit-sequences from the output of an iterative one-way transform. The technique is evaluated using face data and is shown to reliably produce keys of suitable length for 128-bit Advanced Encryption Standard (AES).

Communications advancements in recent decades have led to an increased volume of digital data traveling through publicly shared media. This has led to the rapid development of cryptographic techniques such as AES and public some key architecture. Although keys of sufficient length are strong against both brute force and factorization attacks they still suffer from weaknesses due to insecure key protection by user selected passwords. The limitations of passwords are well documented they are simple and can be easily guessed or obtained using social engineering techniques. They are often written down and stored in an insecure location, can be shared between users, and cannot provide a guarantee of non-repudiation. Furthermore, most people tend to use the same password for a wide range of applications and as a result the compromise of one system leads to the compromise of many others. In recent years researchers have turned towards merging biometrics with cryptography as a means to improve overall security by eliminating the need for key storage using passwords. During the last decade biometrics has become commonly used for identifying individuals. The success of its application in user authentication has indicated that many advantages could be gained by incorporating biometrics with cryptography. A biometric is an inherent physical or behavioural characteristic of an individual such as their voice, face, and fingerprint or keystroke dynamics.

Biometrics, in contrast to passwords, cannot be forgotten, are difficult to copy or forge, impossible to share and offer more security then a common eight character password. The principal drawback of a biometric is that it is not precise like a password or cryptographic key. Limitations of acquisition technology and the inherent changes in the biometric (such as pose and expression for faces) and environmental conditions (such as lighting) lead to variations in each sample of the same biometric. For example, although an iris is considered to be the most accurate of biometrics, there can be up to 30% variation between two different images of the same iris. It is the primary challenges of all biometric cryptosystems to overcome this variation whilst harnessing the advantages of biometrics in order to improve the security of encryption keys. Another challenge stems from the permanence of a biometric. Apart from physical damage, fingerprints or iris remain largely unchanged throughout a person�s life. This is a desired property in most applications of biometrics but in cryptography this is a weakness. Cryptographic keys need to be (and they often are) revoked or changed both proactively as a measure to increase security and reactively as response to key compromise. Most proposed schemes ultimately come down to the protection of an existing cryptographic key with biometric information. While the existing key can be changed the biometric used to secure it cannot and this shortcoming is often neglected.

A cryptographic key generation using face biometric was implemented and verified. A method which uses an entropy based feature extraction process coupled with Reed-Solomon error correcting codes that can generate deterministic bit-sequences was implemented. Combining biometrics with cryptography is a possible solution but any biometric cryptosystem must be able to overcome small variations present between different acquisitions of the same biometric in order to produce consistent keys. Hence the biometric key obtained from the face as been combined with the cryptographic key and the look-up table was generated in order to obtain the cryptographic key while decoding. The method is also flexible, the bio-keys used to protect the cryptographic key can be changed and revoked and is a significant feature not possessed by other methods. The method can be modified to protect keys of increasing length by either increasing the size of bio keys through performing more rotations/iterations of the bi spectral transform or by changing the RS encoding scheme used. A standard 128bit AES algorithm is used here and the obtained cryptographic key is verified using that 128bit AES algorithm

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authors:

PAVANI (Btech RVR&JC COLLEGE OF ENGG.)

S.TILAK (Btech RVR&JC COLLEGE OF ENGG.)

VINOD KUMAR (Btech RVR&JC COLLEGE OF ENGG.)

KRANTHI KUMAR (Btech RVR&JC COLLEGE OF ENGG.)

I sincerely thank authors,the students of "RVR&JC COLLEGE OF ENGG"

for their great support.

my special thanks to v.v.m.m.rao

TO DOWNLOAD FULL PROJECT REPORT CLICK HERE

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VHDL IMPLEMENTATION OF ADVANCED ENCRYPTION STANDARD ALGORITHM

ABSTRACT

The Data Encryption Standard (DES) is a block cipher that uses shared secret encryption. It was selected by the National Bureau of Standards as an official Federal Information Processing Standard (FIPS) for the United States in 1976 and which has subsequently enjoyed widespread use internationally. It is based on a symmetric-key algorithm that uses a 56-bit key. The algorithm was initially controversial with classified design elements, a relatively short key length, and suspicions about a National Security Agency (NSA) backdoor. In recent years, the cipher has been superseded by the Advanced Encryption Standard (AES).

The Advanced Encryption Standard can be programmed in software or built with pure hardware. However Field Programmable Gate Arrays (FPGAs) offer a quicker, more customizable solution. This research investigates the AES algorithm with regard to FPGA and the Very High Speed Integrated Circuit Hardware Description language (VHDL). Xilinx software is used for simulation and optimization of the synthesizable VHDL code. All the transformations of Encryption are simulated using an iterative design approach in order to minimize the hardware consumption.

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authors:

CH.RAVI PHANINDRA (Btech RVR&JC COLLEGE OF ENGG.)

P.GEETHA NATH (Btech RVR&JC COLLEGE OF ENGG.)

N.JAYA RAM(Btech RVR&JC COLLEGE OF ENGG.)

N.NAVEEN (Btech RVR&JC COLLEGE OF ENGG.)

I sincerely thank authors,the students of "RVR&JC COLLEGE OF ENGG"

for their great support.

my special thanks to v.v.m.m.rao

TO DOWNLOAD FULL PROJECT REPORT CLICK HERE

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CELL PHONE OPERATED ROBOT

ABSTRACT

The main aim for design the project is, actually all countries need military force, it is necessary for protecting the country. At the time of wars so many soldiers lost their lives, and country lost the Daring and dynamic personality. So here human lost increasing day by day. We think about it from such a long time how to reduce the human loss. Then we made one equipment to reduce human loss.

Now-a-days Tracing and attacking enemies (or) militants at different areas are very much difficult for the soldiers. We have implemented a solution for the problem by replacing soldier with a Robot Soldiers completely controlled by GSM/CDMA network. This is constructed with two motors. Here two are linear motors . One is for forward and backward rotations (directions), another one is for rotating left and right directions.. The entire Robot is constructed with popular Micro-Controller Series MCS51 series 8051 compatible 89S52 Micro-Controller DTMF network, (GSM Modem) & etc.

Initially we will have to dial up through any GSM network (or) CDMA (or) from any other remote places at least by land line. After completion of the pre-defined rings it enters into the auto answering mode and transmits the picture from the destination area to the controller room that can be watched in any display devices. So according to the picture the person who is there in the control room can take necessary operations

In this project, we present controlling of a robot using DTMF technique. The robot is controlled by a mobile phone that makes call to the other mobile phone attached to the robot. In the course of the call, if any button is pressed, tone corresponding to the button pressed is heard at the other end of the call. This tone is called dual tone multi frequency (DTMF). Using DTMF code, direction of motion of the robot can be controlled by mobile phone.

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authors:

MOUNICA (Btech RVR&JC COLLEGE OF ENGG.)

MAHESWARI(Btech RVR&JC COLLEGE OF ENGG.)

T.SIVA SHANKAR(Btech RVR&JC COLLEGE OF ENGG.)

RAVI RAJ(Btech RVR&JC COLLEGE OF ENGG.)

I sincerely thank authors,the students of "RVR&JC COLLEGE OF ENGG"

for their great support.

my special thanks to v.v.m.m.rao

TO DOWNLOAD FULL PROJECT REPORT CLICK HERE

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WIRELESS NOTICE BOARD USING MOBILE PHONE

ABSTRACT

The aim of this project is to built a prototype of a �wireless notice board� with LCD display using DTMF signaling. In this project we are using two mobile phones.We pass signals from first mobile to DTMF circuit through second mobile phone.The DTMF decoder circuit decodes the signals and sends the output to the microcontroller.Alphabets are not sent directly to the notice board (LCD) at receiver, but sent in the encoded form following an algorithm. This is because the keypad of mobile phone is numerical and DTMF decoded can only decode the number pressed at transmitting mobile in to its equivalent binary at the receiver.Alphabets are sent in an encoded form using numeric keypad to the receiver mobile and DTMF decoder as usually converts the numerical in to its binary equivalent.The decoded binary sequence is sent to the microcontroller which is pre programmed to decode the binary sequence in to respective alphabet and is sent to the LCD display.The LCD displays the encoded alphabet transmitted at the transmitted mobile. And hence the message to be displayed is printed on the LCD display.

Modules:

� Microcontroller

� Mobile phones

� Power supply

� DTMF circuit

� LCD display

Languages & softwares:

� Keil uVision

� Embedded C

� ISP flash programmer

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authors:

P.SHOBHA (Btech RVR&JC COLLEGE OF ENGG.)

S.VENKATESH (Btech RVR&JC COLLEGE OF ENGG.)

T.RAGHURAM (Btech RVR&JC COLLEGE OF ENGG.)

M.KRISHNA KANTH(Btech RVR&JC COLLEGE OF ENGG.)

P.PRABHATH(Btech RVR&JC COLLEGE OF ENGG.)

I sincerely thank authors,the students of "RVR&JC COLLEGE OF ENGG"

for their great support.

my special thanks to v.v.m.m.rao

TO DOWNLOAD FULL PROJECT REPORT CLICK HERE

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CAR THEFT CONTROL

ABSTRACT

This Project presents Micro controller, DSP controller based Electronic Security System. This security system is designed to inform the user(s) by Phone in any case of unsecured situation in his car�s. wherever the equipment is installed. This equipment has magnetic sensors at every ventilation i.e. doors, engine etc. The Passive Infrared sensors (PIR) for human body detection, Piezo electric vibration sensors for detection of vibration of car, etc which will be a closed circuit.

The sensors are in contact when the doors are closed that makes the circuit closed. And if the doors are opened, the circuit breaks and the home lights get switched on. The micro controller waits for the seconds of time specified. In unsecured situations the micro controller Calls the four specified phone numbers through your landline phone connection or GSM modem and transfers the voice message recorded in the DSP controller (address details) and at the same time a loud buzzer sounds at 1000 watts PMPO of power continuously until the system is switched off with a key which is provided only with the product or the password entered through the matrix keyboard. This equipment is designed by using micro controller to give maximum security and digital communication systems. The system has other features like Panic Button, Emergency Doctor�s Button to transfer information about health seriousness to their personal doctors. This equipment works on automatic rechargeable battery during power failures. The link between Sensors and Control Panel is FSK/ASK transmitter & Receiver

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authors:

S.V. SAI KIRAN (Btech RVR&JC COLLEGE OF ENGG.)

M.VIKRAM (Btech RVR&JC COLLEGE OF ENGG.)

V.MURALI MOHAN RAO (Btech RVR&JC COLLEGE OF ENGG.)

G.RAMAYYA (Btech RVR&JC COLLEGE OF ENGG.)

I sincerely thank authors,the students of "RVR&JC COLLEGE OF ENGG"

for their great support.

my special thanks to v.v.m.m.rao

TO DOWNLOAD FULL PROJECT REPORT CLICK HERE

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HOW TO MAKE YOUR OWN POWER SUPPLIES

Every electronics circuit needs a power supply to work, so this post is dedicated to know,how can we construct our own power supply with great ease for varying uses,at low cost and eliminate the use of batteries and adapters.

Here we should convert 220V A.C mains to required D.C voltage,for that follow these sequence of steps:

step1: A transformer converts 220V A.C in to 12V A.C(based on transformer u choose),please do remember that it just steps down the voltage level and nothing more than that. dont be in an illusion that it directly gives D.C.

step2: 12V A.C output of transformer is now rectified by using either full wave rectifier or bridge rectifier based on the tranformer we use.the 12V A.C is having positive and negative peak voltages.so the rectifier does the job of converting bidirectional voltages to unidirection.

step3: the unidirectional voltage peaks given out by the rectifier is now converted to D.C by using filter capacitors. A filter capacitor converts uniderectional wave forms to constant D.C voltages,this is possible by the property of charging and discharging of capacitor.The typical value of a filter capacitor can be 1000uF or 470uF.

step4: up to the step3 we are able to get a D.C. but D.C is unregulated.to regulate this we can use zener diodes or simply a voltage regulator IC.

the voltage output we need can be obtained by using voltage regulators IC s of LM 78XX series.

where XX can be 05,06,09,12...etc

7805 can give a constant output of 5V whatever may be the input supply

7806 can give a constant output of 6V whatever may be the input supply

7809 can give a constant output of 9V whatever may be the input supply

7812 can give a constant output of 12V whatever may be the input supply

hence by choosing XX we can get the required D.C output voltage.

The most important part of a powersupply is a transformer,

The transformer can be two types

1.center tapped(3 output terminals)

2.non center tapped(2 output terminals)

->If we are using a center tap transformer then it will be easy to use a full wave rectifier.

->If we are using a non center tap transformer then it will be easy to use a brigde rectifier.

Just follow this Circuits given below for each tyoe of transformers.

FOR CENTER TAP TRANSFORMER USE THE CIRCUIT BELOW:

FOR NON CENTER TAP TRANSFORMER USE THE CIRCUIT BELOW:

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