1. Power Line Communication using an Audio Input
Hashem AL-khateeb
Abdullah Shab
Ahmed rbaba’h
Tariq Ziad

2. Outline Introduction to general PLC A Detailed Look Proposed Design
Project Build and Tests
Advantages & Disadvantages
Application
Conclusions

3. Introduction to general PLC
Power line communication or power line carrier (PLC), also known as Power line Digital Subscriber Line (PDSL), mains communication, power line telecom (PLT), or power line networking (PLN), is the use of existing electrical cables to transport data, and it has been around for a very long time. Broadband over Power Lines (BPL) uses PLC by sending and receiving information bearing signals over power lines to provide access to the internet.

5. A Detailed Look…
MODULATION
Interference from AC lines which operate at 50 Hz V.
FM modulation necessary to transmit at higher frequencies.
DEMODULATION
Demodulation circuit required to demodulate the modulated signal and convert to standard audio output.
Filter circuits required to block 50Hz noise and any frequencies not part of the transmitted audio.

6. Design Overview

7. Modulation Circuit

8. Modulation Circuit Continued…
The VCO used for modulation purposes was the LM565.
The frequency production of the VCO was controlled using:
where Rt = Timing Resistance on pin 8.
Ct = Timing Capacitance on 9.
Vcc = Power Supply Voltage.
Vc = The control voltage on Pin 7.

9. Demodulation Circuit

10. Demodulation Circuit Continued..
LM565 used to implement the VCO.
The input signal coupled in to the circuit through pin 2.
A more complicated network of components at output for noise reduction purposes.
Potentiometer used to match current frequency to the carrier frequency.

11. Filters Noise above 10Khz was minimal Standard HPF implemented.
Chosen values were R = 15kΩ and C = 1nF

12. Component Selection LM 565 Potentiometers Readily available.
Carrier frequency adjustment through timing capacitor and resistor.
Potentiometers
Easy tuning manipulation

13. Design and Testing 1) Build Modulator/Demodulator.
2) Test Modulator/Demodulator Functionality.
3) Build Filters.
4) Test Filter Functionality.
5) Combine Modulator/Demodulator with Filter.
6) Test Transmitter/Receiver Functionality.
7) Combine Transmitter/Receiver with 50 Hz Simulated Noise.
8) Test with Simulated Noise.
9) Combine Transmitter/Receiver with 50 Hz Power Line.
10) Test with Power Line (Variac).

14. Board Layout

15. Board Layout - Transmitter

16. 100 kHz FM Modulated Signal
Modulator Testing
Computer
Audio Signal
Modulator
100 kHz FM Modulated Signal

17. Timing Capacitor (pin 9):
~100 kHz
Modulator output :

18. Board Layout-coupling stage

19. Board Layout-receiver

20. Demodulator Testing
DC Power
Demodulator
(No signal)

21. Timing Capacitor (pin 9):

22. Filter Testing
Filter
Input Signal
50 Hz
100kHz
Output Signal

23. 50 Hz Response:
Gain = .01 V/V
100 kHz Response:
Gain = .98 V/V

24. Integration Testing Speaker Computer Demodulator Modulator Power Strip
(Filter)
(Filter)

25. Qualitative Evaluation
-Clarity of signal (after tuning)
Quantitative Evaluation
- SNR (at 10 kHz) dB

26. Communication with simulated 50Hz
Speaker
Simulator
50 Hz, 20 volts
Computer
Power Strip
Demodulator
Modulator

27. Qualitative Evaluation
-Clarity of signal (after addition tuning)
Quantitative Evaluation
- SNR (at 10 kHz) dB

28. Communication over Power Line
Speaker
Power Line
50 Hz, 220 volts
Computer
Power Strip
Demodulator
Modulator

29. Challenges - Filter Performance
Relative background noise persistent through the initial filter design.
DC offset distortion of the output signal
DC offset connected to ground through inductors causing over current conditions.
Proposed three stage RC filter design

30. Filter Performance

31. Advantages of PLC Low cost. Low power consumption.
data over PLs was used for protection.
Data rates above 1Mbps.

32. Disadantages of PLC Ground Issues.
Radiation of the Transmitted Signal.
Impedance Mismatches.
The Time-variant.

33. Application OF PLC VoIP (Voice over IP). VoD (Video On Demand).
Online Gaming .
AMR (Automatic Meter Reading) .
Smart Home Management .
Power Grid Management and Control .
Local Area Network (LAN).
Wide Area Network (WAN)
CCTV and Security Networks

34. Conclusions
This telecommunications model has multiple advantages over others including speed, an established local loop, and dedicated connections. These advantages make Power Line technology an attractive alternative for telecommunications systems.
Power line communication uses the existing power lines within a home, building or an outdoor power distribution network to transmit data from one device to another. With a well-designed power line solution, devices should be able to communicate using the existing wiring infrastructure, without any rewiring or modification. This makes power line communication one of the most cost-effective means for networking devices.

35. QUESTIONS?