Bluetooth Enabled Smart Device for Attendance Monitoring with Feedback System Nowadays in the modern trend Communication takes place through wireless only. Mostly is Wireless Communications there will be a Transmitter unit and a Receiver unit and the type of transmission can be Infrared, RF, Bluetooth etc. Here, the problem is the communication is Simplex communication i.e., One end we can transmit data and on the other end we can receive data. No duplex communication is possible. To overcome this factor, we can develop a project in which we can send and receive data in wireless. This will be useful for many applications such as in hospitals, schools, colleges etc. Here in our project we have an idea to have an Hand held device in which we have a transmitter and a receiver unit fixed in that device where we can enable the transmitter, Send a message and deactivate it. Then Activate the receiver unit wait for the acknowledge or for the data to come in and deactivate it. The other side also has a similar unit. For the Hand Held device we have decided to use a pic microcontroller with LCD Display and Keypad. We have decided to use a Bluetooth Transmitter and Bluetooth Receiver unit whose frequency is 2.4Ghz.

1. Bluetooth Enabled Smart Device for
Attendance Monitoring with Feedback
System
Nowadays in the modern trend Communication takes place through
wireless only.
Mostly is Wireless Communications there will be a
Transmitter unit and a Receiver unit and the type of transmission can be
Infrared, RF, Bluetooth etc.
Here, the problem is the communication is
Simplex communication i.e., One end we can transmit data and on the
other end we can receive data. No duplex communication is possible. To
overcome this factor, we can develop a project in which we can send and
receive data in wireless.
This will be useful for many applications such as in hospitals, schools,
colleges etc. Here in our project we have an idea to have an Hand held
device in which we have a transmitter and a receiver unit fixed in that
device where we can enable the transmitter, Send a message and
deactivate it. Then Activate the receiver unit wait for the acknowledge or
for the data to come in and deactivate it. The other side also has a similar
unit.
For
the
Hand
Held
device
we
have
decided
to
use
a
pic
microcontroller with LCD Display and Keypad.
We have decided to use a Bluetooth Transmitter and Bluetooth
Receiver unit whose frequency is 2.4Ghz.
89. Rangarajapuram main road,(Near SBI Bank),Kodambakkam
Chennai-600024, http://www.maastechindia.com

2. Block Diagram
Attendance Side:
Personal Computer
Bluetooth Module
RS232
+5V Power Supply
89. Rangarajapuram main road,(Near SBI Bank),Kodambakkam
Chennai-600024, http://www.maastechindia.com

3. Hand Held Device (Person/Student Side):
Bluetooth Module
Signal Converter
Circuit
+5V Power Supply
PIC16F877
Microcontroller
Keypad
89. Rangarajapuram main road,(Near SBI Bank),Kodambakkam
Chennai-600024, http://www.maastechindia.com
LCD

4. BLUETOOTH TECHNOLOGY
Bluetooth technology is an industry wireless specification standard
for use in various devices for short-range communications. As a radiobased technology it allows devices to share information over a maximum
range of 10 meters. Bluetooth enables mobile computers, mobile phones,
portable handhelds, and the Internet to “talk the talk” without cables. With
bluetooth, devices don't need to be 'looking' at each unlike other wireless
technologies (i.e. infrared). As long as two bluetooth devices are close
enough to each other, it’s possible to make a connection. With bluetooth
technology getting connected takes on a whole new meaning.
Bluetooth communicates on a frequency of 2.45 gigahertz, which has
been set aside by international agreement for the use of industrial, scientific and
medical devices (ISM) A number of devices that you may already use take
advantage of this same radio-frequency band. Baby monitors, garage-door
openers and the newest generation of cordless phones all make use of
frequencies in the ISM band. Making sure that Bluetooth and these other
devices don't interfere with one another has
been a crucial part of the design process.
It is unlikely that several devices will be on the same frequency at
the same time, because Bluetooth uses a technique called spread-spectrum
frequency hopping. In this technique, a device will use 79 individual, randomly chosen
frequencies within a designated range, changing from one to another on a regular basis. In the
case of Bluetooth, the transmitters change frequencies 1,600 times every second, meaning that
more devices can make full use of a limited slice of the radio spectrum Since every Bluetooth
transmitter uses spread-spectrum transmitting automatically, it’s unlikely that two transmitters will
89. Rangarajapuram main road,(Near SBI Bank),Kodambakkam
Chennai-600024, http://www.maastechindia.com

5. be on the same frequency at the same time. This same technique minimizes the risk that portable
phones or baby monitors will disrupt Bluetooth devices, since any interference on a particular
frequency will last only a tiny fraction of a second.
When Bluetooth-capable devices come within range of one another,
an electronic conversation takes place to determine whether they have
data to share or whether one needs to control the other. The user doesn't
have to press a button or give a command -- the electronic conversation
happens automatically. Once the conversation has occurred, the devices -whether they're part of a computer system or a stereo -- form a network.
Bluetooth systems create a personal-area network (PAN), or piconet, that
may fill a room or may encompass no more distance than that between the
cell phone on a belt-clip and the headset on your head. Once a piconet is
established, the members randomly hop frequencies in unison so they stay
in touch with one another and avoid other piconets that may be operating
in the same room.
Most of the time, a network or communications method either works
in one direction at a time, called half-duplex communication, or in both directions
simultaneously, called full-duplex communication. A speakerphone that lets you either listen or
talk, but not both, is an example of half-duplex communication, while a regular telephone handset
is a full-duplex device. Because Blue tooth is designed to work in a number of different
circumstances, it can be either half-duplex or full- duplex.
Benefits
Depending on your needs and the blue tooth enabled device, you can hope
to gain several benefits from using blue tooth technology in your
environment. Some of the benefits are:
89. Rangarajapuram main road,(Near SBI Bank),Kodambakkam
Chennai-600024, http://www.maastechindia.com

6. •
Connecting devices without the need for cables
•
Becoming more integrated within laptops, mobile phones, handhelds,
and many other devices
•
Reduced power consumption
•
Industry wireless communications standard
89. Rangarajapuram main road,(Near SBI Bank),Kodambakkam
Chennai-600024, http://www.maastechindia.com

7. •
Connecting devices without the need for cables
•
Becoming more integrated within laptops, mobile phones, handhelds,
and many other devices
•
Reduced power consumption
•
Industry wireless communications standard
89. Rangarajapuram main road,(Near SBI Bank),Kodambakkam
Chennai-600024, http://www.maastechindia.com