This document discusses the design of a sniffer device to detect lost mobile phones. It begins with an introduction describing how thousands of mobile phones are lost daily and the need for a device to locate them. It then provides details on IMEI numbers, which uniquely identify each phone. The document defines a sniffer as a transceiver that can detect phones by operating at a different frequency than the mobile network. It describes the key components of the sniffer as a small base station, directional antenna, and tracking software. Advantages are listed as low cost, power efficiency and mobility. Disadvantages include the complexity of design and need for the mobile phone to have sufficient power and not be in a shadow region.

1. I.AKHILA
12761A0574

2. INTRODUCTION
 THE MAIN SCOPE OF THIS IS TO DETECT THE LOST
MOBILES
 Each and every day thousands of mobiles have been lost or
misplaced
 Though the effective way for blocking of the lost mobile to
prevent making or receiving the calls has been done by the
manufacturers of the mobiles with the help of IMEI number
 For the detection of the lost mobiles sniffer plays an important
role
 Sniffer has to be designed very precisely and size should be
reduced for mobility and or the detection

3. INTRODUCTION TO IMEI
 Each mobile device has a unique IMEI number(international mobile equipment identity)
 IMEI numbering is 15 digit unique code that is used to identify GSM phone
 To know the IMEI number *#06# should be pressed the number displayed in the LCD
screen.
 When a phone is switched on, this unique IMEI number is transmitted and checked
against a data base of black listed or grey listed phones in the network’s EIR
 Grey listing will allow the phone to be used, but it can be tracked to see who has it (via
the SIM information)

4. what a SNIFFER is?
The sniffer is basically a transceiver that works in the frequency which
is the special unused range that is operated by service provider or
it can be designed to operate at a frequency that is of much different
frequency than the one that is being used.

5. DESIGNING FOR THE SNIFFER
The sniffer device can be called as a mobile
base station that includes the following important
components:
1.Sniffer base station
2. Unidirectional antenna
3.Tracking software

6. SNIFFER BASE STATION
The sniffer is a small base station, it includes
transceiver section.
It should not operate at a frequency equal to the
frequency of the cell
It should operate at a frequency that is much
different from the frequency of the current cell in
which the operation of detection is being carried
out.

7. UNIDIRECTIONAL ANTENNA
The directional antenna acts as the eyes for
the sniffer for the purpose of the detecting
the lost mobile phones.
Antenna is a device which works at specified
frequencies range for transmitting or
receiving the data signal.
In general, antennas transmit power
depending on lobe pattern which varies
from one antenna to the other

9. SOFTWARE FOR TRACKING
The software is used for the tracking
of the lost mobile phone
The programming is done with C or
Java. However the C is most preferred as
it is easily embedded with the chips

12. Fig: the sniffer shown in fig tries to communicate
with the lost mobile.

13. ADVANTAGES
This method is used for finding
the lost mobiles effectively
Cost effective
low power consumption
Easy for the mobility

14. DISADVANTAGES
 Though this method appears to be a little bit complex
involving the design of the sniffer.
 The power of the mobile should be good enough , the
mobile phone should not be in the shadow region.

15. CONCLUSION
 This topic deals about the idea of development
“Sniffer for the detection of lost Mobile phones”
paves a way by means of which the lost mobile
phones can be recovered. But the process of detection
is yet to be developed through the software and demo
has been developed .