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Altera_Forum
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16 years ago

QAM modulation technique using verilog

Hi all, Anyone knows how to do Quad amplitude modulation QAM (16 or 64) doesnt matter.. using verilog? Please help me. Thanks.. -John- Kuala Lumpur
Altera_Forum's avatar
Altera_Forum
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16 years ago

Here are some practical principles:

1) get your input vector(bit stream or bytes)

2) convert to sets of 4 bits(16QAM) or 6 bits(64QAM).

assume one set is I symbol, the other Q symbol

3) map your symbols to your chosen constellation e.g. if I = 0000 then assign

+1023 to your symbol (for 11 bit DAC resolution) and so on.

4) then comes the hard bit: shaping/upsampling to DAC speed...