Audio and Data module system

In MODCOM-3, various techniques of baseband data transmission currently used in digital communications systems are studied. Data signals are converted into Baseband sequence of data symbols. Specifically, 2B1Q and AMI/TBC coders are studied.The module also contains a transmission channel, a receiverand two different time recovery synchronization circuits.The pseudo-random sequence generator in MODCOM-1 acts as theinformation source. Data signals are measured in both the time and frequency domain using the PU-400 interface to the personal computer. The white noise generator and bit error rate (BER) meter, supplied by the PU-410 RF service unit, replace expensive test equipment.Module DescriptionThe Baseband Transmission and Synchronization moduleMODCOM-3 provides a number of communication functions thatenable the student to perform meaningful and interesting experiments.MODCOM-3 consists of the following:2B1Q coder AMI/TBC coder Transmission channel with variable bandwidth Receive filter Line equalizer Integrate & dump filter Slicer & decision circuit with variable threshold and sync. input 2B1Q decoder AMI/TBC decoder Time recovery using a squaring circuit Time recovery using a zero-crossing PLL Clock jitter circuit Recommended Experiments1. Twinned Binary Code2. AMI Code3. Comparison of AMI with 4-level PAM (2B1Q) 4. Intersymbol Interference (ISI)& Eye Pattern5. Time Recovery With Squaring Circuit6. Time Recovery with Zero Crossing Circuit7. AMI Noise Performance8. 2B1Q Noise Performance9. Timing Recovery Performance