This is a Communication System Project(Electronics Engineering).In this project we are transmit the the voice signal by transceiver in different conditions 1.Normal Condition 2.Ab-normal Conditions(With interrupt input signals)

1. Communication System
1Sunil Kumar Shesma

2.  Introduction
 Apparatus
 Circuit Diagram
 Technical Details
 Technical Specifications
 Working
 Conclusion
 References
2Sunil Kumar Shesma

3.  A transceiver is using transmit the signal as
well as receive the signal.
 It is a device comprising both a transmitter
and a receiver that are combined and share
common circuitry or a single housing. When
no circuitry is common between transmit and
receive functions, the Device is a transmitter-
receiver.
 It is a Wireless Digital Audio Streaming
Realtime with Arduino and nrf24L01 module
based project.
3Sunil Kumar Shesma

4.  nrf24L01 module is highly integrated, ultra
low power(ULP),2Mbps RF transceiver IC for
the 2.4Ghz ISM(Industrial, Scientific and
Medical) band.
 In this project, We are using transmitting the
voice signal using nRF24L01 module in
following conditions:
1.Normal Condition
2.Ab-normal Condition(With interrupt input
signal)
4Sunil Kumar Shesma

5.  nRF24L01 Module
 Arduino UNO
 Electret Microphone
 Npn transistor
 Buttons
 3.5 mm jack breakout
 Breadboard
 10k resistor
 100k resistor
 100nF Capacitor
5Sunil Kumar Shesma

6. 6Sunil Kumar Shesma

7.  nRF24L01 Module:
The nRF24L01 is a single chip 2.4GHz
transceiver with an embedded baseband
protocol engine designed for ultra low power
wireless applications. An MCU (microcontroller)
and very few external passive components are
needed to design a radio system with the
nRF24L01.
7Sunil Kumar Shesma

8.  Arduino UNO:
The Arduino Uno is a microcontroller board
based on the ATmega328 (datasheet). It
contains everything needed to support the
microcontroller; simply connect it to a
computer with a USB cable or power it with a
AC-to-DC adapter or battery to get started.
8Sunil Kumar Shesma

9.  nRF24L01:
Transmitter
Programmable output power: 0, -6, -12 or
-18dBm
11.3mA at 0dBm output power
Receiver
Integrated channel filters
12.3mA at 2Mbps
-82dBm sensitivity at 2Mbps
-85dBm sensitivity at 1Mbps
Programmable LNA gain
9Sunil Kumar Shesma

10.  Microcontroller
ATmega 328
 Operating Voltage 5V
 Input Voltage
(recommended) 7-
12V
 Input Voltage (limits)
6-20V
 Digital I/O Pins 14 (of
which 6 provide PWM
output)
 Analog Input Pins 6
 DC Current per I/O
Pin 40 mA
 DC Current for 3.3V
Pin 50 mA
 Flash Memory 32 KB
of which 0.5 KB used
by bootloader
10Sunil Kumar Shesma

11.  Gathers the tools
 Microphone Circuit
 Call Button
 Add Speaker
 Wireless transmission
 Ardiuno Code
11Sunil Kumar Shesma

12. Microphone Circuit :
it will produce an AC
current at the base of the
transistor based upon the
sound wave hitting the
microphone. The base
current of the transistor is
amplified and so we have
an amplified sound wave
that we are feeding into
our microcontroller.
12Sunil Kumar Shesma

13.  Call Button:
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14. Call Button:
Here we have used a simple pushbutton,10 k resistor,
and a 100 nF capacitor.
 With this piece of code, we go to the "talk()" function
which checks the voltage on pin 3.
 If the voltage is HIGH or 5 V, the nRF24L01 will switch
to transmit mode (sending voice). If the voltage is
LOW or 0 V, the nRF24L01 will switch to receive mode
(receiving voice). The voltage on pin 3 should be
HIGH when the button is pressed and LOW when the
button is released.
 Whenever the voltage on pin 3 "CHANGES" as denoted
in our "attachInterrupt" function, the "talk()“ function
will execute.
14Sunil Kumar Shesma

15.  Add Speaker:
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16. Wireless
Transmission:
 nRF24L01 to Arduino
 1. Ground to Ground
 2. Vcc to 3.3 V (NOT 5
V)
 3. CE to digital pin 7
 4. CSN to digital pin 8
 5. SCK to digital pin 13
 6. MOSI to digital pin 11
 7. MISO to digital pin 12
 8. IRQ to digital pin 2
16Sunil Kumar Shesma

17.  Ardiuno Code:
 We put together a simple code utilizing the
RF24 and RF24Audio libraries.
 Upload this code to both Arduinos. Both
circuits with default to "receive“ at the start of
the code. Press the "call button" to transmit
audio from one radio to the other.
 Remark: The RF24Audio is using PWM and
some other techniques to transmit audio.
17Sunil Kumar Shesma

18.  With the help of our transeceiver module, we
can transmit the voice signals upto
100meters.
 Here, For getting less interrupt we can use
the less bandwidth low pass filter.
18Sunil Kumar Shesma

19.  https://www.google.co.in/url?sa=t&source=web&r
ct=j&url=http://www.instructables.com/id/Wristwa
tch-
WalkieTalkie/&ved=0ahUKEwi6lKyu_63SAhUDULwK
HYv8AfsQFggZMAA&usg=AFQjCNESRlVxZZhszA-
GlmmVLPyyF7QE7Q&sig2=GZSeTZkyUUciXraVuVcA
GQ
 https://hackaday.io/project/8598-wristwatch-
walkie-talkie
 http://cassiopeia.hk/walkietalkie/
19Sunil Kumar Shesma

20. Thanking you
20Sunil Kumar Shesma