I'm not a c-programmer, rather a guy who inherited a system that previously had an I/Q demodulation in a gate array, need to move it into c-code. I have 1024 sample buffer that was synchronously digitized with x4 clock, so samples are alternately +I, +Q, -I, -Q,....... Need a snippet of code that flips signs of alternate I's and Q's so they are all positive, then sums the I's and Q's. I know this is trivial for a c-programmer, but not so for a non-programmer. Can anyone point me to an example, please?