ABSTRACT

This method uses external circuits that are to be added into the Cell Phones, which has many categories, where all the drawbacks are being put forth. This project is considered as commercial and more practical. The input jamming signal frequency is in the order of 400Mhz. The deactivation of LCD panel and speaker is done through a micro controller 89c51. This project gives total solution for both the customers and the network service providers. Whereas in conventional jammers the user gets totally no signal message, in our project this problem is avoided so important calls are not missed.

EXISTING SYSTEM:

Jammers fully disconnects the conenction between

the mobile node and the Base station.

Jammers interferes in other wireless networks also.

Jammers will cause huge loss to service providers.

In this Project, we are modifying the jammer concept because of this we have two advantages, one is that we get rid of legal problems because we have to use 900 MHZ oscillators the other one is that we let the mobile user to know the caller identity.

PROPOSED SYSTEM

SCHEMATIC SETUP

400 Mhzrx

speaker400 Mhztx

Micro controller

switches

Display section

BLOCK DIAGRAM

DETECTEDCODE

PIN DIAGRAM OF 89C51

LITERATURE REVIEW

ARCHITECTURE OF 89C51

Literature Review – Microcontroller (ATMEL 89C51)

I/O Ports

Port 0 (8 lines)

Port 1 (8 lines)

Port 2 (8 lines)

Port 3 (8 lines)

FEATURES OF 89C51

It is a low-power, high-performance.

CMOS 8-bit micro computer.

128 x 8-Bit Internal RAM.

Two 16-Bit Timer/Counters.

Programmable Serial Channel.

Low Power Idle and Power Down Modes.

32 Programmable I/O Lines.

Six Interrupt Sources.

POWER SUPPLY DIAGRAM

7805

BLOCK DIAGRAM-EXPLANATION

The basic functionality of our project could be divided

into following two sections.

Transreceiver

» Transmitter Section

» Receiver Section (in mobile device)

Transmitter section:

The transmitter section consist of 400 mhz transmitter in omni direction.

Receiver section

The Receiver section consist of 400 mhz

receiver which is interfaced with the

microcontroller.

CIRCUIT EXPLANATION

When they gets the signal from the receiver receives the

signal and decode the signal and compare the predefined

value and then it does the de activation of key board and

speaker as long as the person is inside the coverage distance

of the jammer.

Features Operating voltage:2.4V~12V for the HT12E Low power and high noise immunity CMOS technology Minimum transmission word’s of 4 words for the HT12E Built-in oscillator needs only 5% resistor Data code has positive polarity Minimal external components HT12E: 18-pin DIP/20-pin SOP package

HT-12E ENCODER

The 2^12 encoders are a series of CMOS LSIs for remote control system applications.

They are capable of encoding information which consists of N address bits and 12N data bits.

Each address/data input can be set to one of the two logic states.

The programmed addresses/data are transmitted together with the header bits via an RF transmission medium .

Transmission is enabled by applying a low signal to the TE pin.

DESCRIPTION

It also operates at 433.92MHz, and has a sensitivity of 3uV.

It operates from 4.5 to 5.5 volts-DC,

It has both linear and digital outputs.

RF RECEIVER

Operating voltage: 2.4V~12V Low power and high noise immunity CMOS technology Low standby current Capable of decoding 12 bits of information Binary address setting Received codes are checked 3 times Address/Data number combination - HT12D: 8 address bits and 4 data bits Built-in oscillator needs only 5% resistor Valid transmission indicator Easy interface with an RF transmission medium Minimal external components Pair with Holtek's 212 series of encoders 18-pin DIP, 20-pin SOP package

HT12D DECODER

MERITS:

No loss for service providers.

The identity of the caller is shown in the display.

No interference created to any electronic deivce.

No license problem at 400 MHZ carrier frequency.

APPLICATIONS

Mostly in Educational institutes and temples and

conference halls

With some modifications we can provide this

service in industries or in secured places during the

restricted hours/timings.

FUTURE ENHANCEMENTS

The circuit may be designed with ASIC.

By increasing the coverage distance the jamming

device will become still efficient.

May be the identity of the user can be detected.

Work Schedule

Review 1 Review 2 Review 31. Selection of Project.

2. Study of programming concepts of microcontroller.

3. Study of basic concepts of all sensors.

1. Preparation of hardware system.

2. Integrating internal system through program.

Implementation of our project.

APPENDIX

THANK YOU