People,

I need to write some code (Matlab or IDL) to simulate a CDMA system.

I am having issues with knowing what to add and multiply modulo 2.

If I have my spread spectrum codes in -1,+1 format (ie: not 0, 1) whats the deal?

Also... im trying to get something basic to start with, like having 2 signals each with their own PN sequence {gold codes in this case}, add them and try and get an original signal back by multiplying again with a PN sequence, but it doesnt work.

Do i need a signal to modulate these onto?

Do i need to reverse the vectors at the end because of how matlab multiplies?

Any ideas?

I plan to implement matched filters, noise etc @ some stage.

Cheers.

Mr Tulip.