Simple demo of adm of speech signal using matlab progrmming

1. Adaptive
Delta
Modulation
for Speech
Signal K Sai Malleswar
By:
Kshitiz Sinha
Kumar Harshit
L. Deepak

2. Topics and Steps
1 • Sampling
2 • Quantization
3 • Delta modulation
4 • Adaptive delta modulation
5 • Demodulation
6 • Conclusion

3. Topics and Steps
• Sampling:
sampling theorem
• Quantization:
types of Quantization

4. Topics and Steps
• Delta Modulation
• Errors in Delta
modulation

5. Topics and Steps
Adaptiveness
• Increasing or decreasing the step size according to the
error ………

6. The system
Adaptive delta Demodulation
Signal acquisition
modulation
Calculating maximum
Recording speech Receiving and decoding
variation in message
using Wavrecord the data
signal and step size
Calculating error and Reconstructing
plotting the
adapting step size delta (demodulating) the
sampled signal
signal
Transmitting data using
DAT files in binary form Signal conditioning

7. Signal acquisition
• The real time signal is recorded using
“Wavrecord” command.
y = wavrecord(n,Fs,'dtype')

8. Adaptive delta modulation
Calculating maximum
Calculating error and Transmitting data using
variation in message
adapting step size delta DAT files in binary form
signal and step size
Choosing step size as
.0001*max

9. Adaptive delta modulation
Calculating maximum
Calculating error and Transmitting data using
variation in message
adapting step size delta DAT files in binary form
signal and step size
Adjusting
delta value

10. Adaptive delta modulation
Calculating maximum
Calculating error and Transmitting data using
variation in message
adapting step size delta DAT files in binary form
signal and step size

11. Demodulation
Reconstructing
Receiving and decoding
(demodulating) the Signal conditioning
the data
signal

12. Demodulation
Reconstructing
Receiving and decoding
(demodulating) the Signal conditioning
the data
signal

13. Demodulation
Reconstructing
Receiving and decoding
(demodulating) the Signal conditioning
the data
signal
Can use this step
depending on the
noise present.

14. Performance parameters
• When the sampling frequency is „22000
Hz‟ then the required band width is “42.97
Kbits/sec”.
• The compression ratio obtained is 8.