ScienTECH ST2115, Руководство пользователя

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ST2115
Scientech Technologies Pvt. Ltd. 42
5. Connect binary data and PN sequence outputs to the Ex-OR gate of DSSS
block. Connect the output of DSSS block to the input of unipolar to bipolar
converter. Take the output of this converter to the input of BPSK modulator.
Connect sinusoidal carrier from Carrier Generator to the carrier input of BPSK
modulator. This completes the modulator connections
6. Now Connect output of BPSK modulator to the input of BPSK demodulator
block. Connect output of this block to the comparator input. Here we would
receive original chipped data.
7. Connect the recovered chipped data (output of comparator) to one the inputs
of data recovery block. Connect ‘PN Sequence for Despreading’ output of PN
sequence generator block to the other input of data recovery gate.
8. Now turn power supply ‘On’. Observe data and PN sequence at their
respective output pins. Press load button if data is not appearing.
9. Observe the output of DSSS block. This is called ‘chipped data’.
10. Observe the output of BPSK modulator. This is RF modulated chipped data.
11. Observe the output of comparator and then Data Recovery Block. Adjust
phase of recovered carrier in BPSK modulator section and bias of comparator
until you see a complete replica of original binary data.
12. Change data pattern and repeat the whole procedure with this new data. Again
adjust phase and bias of comparator so as to recover the data completely.
13. Change chip (PN Sequence) pattern and observe the results.
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