Hello
I am building a CDMA simulation software and i have a question?
I know that CDMA based on spreading data with PN codes by preforming xor operation between each bit of data to the PN sequence and also for multi user i need to spread the data by walsh code before i spread it by PN sequence(am i right????).
So my question is :In order to create walsh code i need to generate wlash matrix and each user spred's his data bit by one of the rows of walsh matrix am i right?(also bu preforming xor) and another thing i know that i need to preform walsh transform but i don't know were i need to do it (maybe i am wrong and i don't ) and how?
Another thing i want to modulate this data by QAM so i was wondering if i need to spred the data and the to split it to IQ or first spread it and than create symbols for IQ?
Thx.