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Altera_Forum
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11 years ago

Costas Loop oscillates in ModelSim while locks in MATLAB!

Hello again, I have designed a Costas Loop in MATLAB and it simulates very well... locking and recovering the carrier. Here are the results: http://www.alteraforum.com/forum/attachment.php?...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

1) Did you use multiplier as phase detector?

2) You didn't need RRC inside the loop because you took I/Q directly, right?

3) Do I update the nco word as you did? once every 10 samples? How do you revert back to initial word? I mean do you update nco word with error sample for one clock cycle only?