Objective
Generation and detection of Delta Modulation.
Aim of the Experiment
To study the generation and detection of Delta Modulation.
Equipment Required
Delta Modulation and Demodulation Trainer Kit
Digital Storage Oscilloscope (100MHz, 1GSa/S)
Power supply
Probes
Patch cord
Connecting wires
Theory
Delta Modulation is a form of pulse modulation where a sample value is represented as a single bit. This is almost similar to differential PCM, as the transmitted bit is only one per sample just to indicate whether the present sample is larger or smaller than the previous one. The encoding, decoding and quantizing process become extremely simple but this system cannot handle rapidly varying samples. This increases the quantizing noise.
Procedure
The connections are given as per the block diagram.
2. Connect power supply in proper polarity to kits DCL-07 and switch it on.
3. Keep the Switch S2 in Delta position.
4. Keep the Switch S4 High.
5. Observe the various tests points in delta demodulator section and observe the reconstructed signal through 2nd order and 4th order filter.
Block Diagram / Circuit Diagram
Graph
Observation Table
Signal | Amplitude | Time period | Frequency |
Message Signal | |||
Digital Sampler Output | |||
Integrator-3 Output | |||
Filter Output |
Result
Delta Modulation and Demodulation are verified in the hardware kit and its waveforms are studied.
Conclusion
From the above experiment, the amplitude of demodulated signal is obtained as ..........
Precautions
1) Do not use open ended wires to connect 230V, 50Hz power supply.
2) Check the connection before giving the power supply.
3) Observations should be done carefully.
4) Disconnect the circuit after switched off the power supply
Tags:
Image Credits: Freepik