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Altera_Forum
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17 years ago

OFDM using DSP Builder

Hi, I'm trying to implement a simplistic (4 channel) QPSK OFDM transmitter/receiver using Altera's DSP Builder and Megacore IP in Simulink. Let me just mention that I have very basic knowl...
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Altera_Forum
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17 years ago

Hi Kaz,

Even if I scale by multiplication of 2^-exp, I'm getting the same problem. The output scales in the wrong direction, its only equal to the Matlab IFFT output if I multilpy by 2^exp. I triple checked my code, it seems to be correct. Attaching my new .m file.

My overall goal is to build an OFDM transceiver in DSP Builder using only Altera blocks, currently I'm stuck at the IFFT step of the transmitter. The matlab code was just to test my understanding of the Altera IFFT block and make sure I'm getting the correct result from it before I implement it in my design.

The real problem here, is what I showed you in my previous post. In DSP Builder, using the same exact parameters of the Altera IFFT block, I'm getting different wave output (not scaled, but completely different shape) from DSP Builder Altera IFFT block compared with Altera IFFT block used from Matlab.