Digital Communications Description and Specifications for Lab Tenders
Digital Communications.
>Experiment Trainer board that Contains:-
Crystal controlled pulse generator;
Sine Wave Generator - Provides Synchronized Sine waveform output of Frequency 1 KHz & 2KHz.
Pulse Generator-Switch selectable sampling frequency of 2,4,8,16, 32 KHz,
Internal/ External sampling signal selectable
Separate sample and sample/hold outputs available
Experiments:-
Study the Sample signal and Sample/Hold signal and its reconstruction;
Study the effects of different Sampling;
Study the effects of 2nd and 4th Order low pass filters for the reconstruction of the signal frequencies on the reconstructed signal;
Study the effects of Varying duty cycle of Sampling frequencies on the amplitude of the reconstructed signal
TDM PAM MULTIPLEXING AND DEMULTIPLEXING TRAINER
>Experiment Trainer board that Contains:-
On-board pulse generator.
4 Analog input channels sampled and time division multiplexed.
Pulse duty cycle selectable.
Internal/External sampling selectable.
4 Channel De-multiplexer.
Generation of clock at receiver by PLL System.
4th Order Butterworth L.P. filter.
Experiments:-
Study of Time Division Multiplexing and Demultiplexing using Pulse Amplitude modulation and demodulation
Study of TDM Pulse Amplitude modulation and demodulationWith Channel Identification Information
Study of TDM Pulse Amplitude modulation and demodulation using PLL method
TDM PULSE CODE MODULATION TRANSMITTER TRAINER
>Experiment Trainer board that Contains:-
Crystal Controlled Clock.
On-board Sine wave generator (Synchronized)
2 TDM Analog Channels.
PCM Transmitter.
Fast & Slow modes for real time operation and data flow examination.
Error check code options (odd-even parity, Hamming Code).
Sound input from mike
4 Switched faults allow different Error Check Options.
PC - PC Communication via RS 232 interface.
Experiments:-
Study of Pulse Code Modulation.
Sound transmitting from mike
Study the principles of ADC &DAC
Study of Pseudo Random Sequences
Study of Error Check Code Logic:
- None Parity Coding.
- Odd Parity Coding
- Even Parity Coding
- Hamming Coding
Study of effect of faults in Modulation & Demodulation Techniques.
TDM PULSE CODE DEMODULATION RECIEVER TRAINER
>Experiment Trainer board that Contains:-
Input accepts two channel multiplexed data.
On board De-multiplexed PCM Receiver.
On board L.P. Filter.
Fast & Slow modes for real time operation and data flow examination.
On board PLL for clock regeneration.
On board sync code detector.
Error check code options.
Odd or Even Parity-Single bit error detection.
Output through speaker
Experiments:-
Study of PCM Demodulation Technique
Study of Time Division Demultiplexing of PCM data
Study of Clock Regeneration by PLL Study of Detection & Correction of Error induced by switched faults in the transmitter.
Study of signal recovery in 3 connecting modes between transmitter & receiver
Study of Importance of Clock and Frame Synchronization in PCM system
Study of the effect of induced faults in receiver.
Sound receiving at loudspeaker
DATA FORMATTING AND CARRIER MODULATION TRAINER
On-board Carrier generation circuit (Sine waves synchronized to transmitter data).
On-board in phase and quadrate phase carrier for QPSK modulation.
Different data conditioning formats NRZ (L), NRZ (M), RZ, Biphase. (Manchester), Biphase (Mark), AMI, RB, differentially encoded dibit pair.
FSK, PSK, ASK ,DPSK & QPSK carrier modulation.
Variable carrier and modulation Off-Set.
Variable carrier gain.
On-board Unipolar to Bipolar conversion.
On-board data inverter.
Experiments:-
Study of Coversion of NRZ data to other data formats NRZ(L), NRZ(M) RZ, AMI, RB, Biphase (Manchester), Biphase (Mark), Differentially encoded dibit pair
Study of following Carrier Modulation Techniques and their comparison-ASK, FSK,PSK & QPSK
DATA REFORMATTING & CARRIER DEMODULATION TRAINER
>Experiment Trainer board that Contains:-
7 different data reconditioning formats NRZ (M), RZ, AMI, RB Biphase (Manchester), Biphase (Mark), differentially encoded dibit to NRZ data.
ASK, FSK, PSK, DPSK & QPSK carrier demodulation.
Output gives 2 Channels TDM multiplexed data output.
On - Board Biphase Clock recovery circuit.
On - Board data squaring circuit and differential decoder.
On - Board Butterworth filters - 4th Order (2 nos.)
Experiments:-
Study of Conversion of different data formats to NRZ data format.
Study of various Carrier Demodulation Techniques (ASK, FSK, PSK ,DPSK & QPSK)