On Tue, Jun 20, 2006 at 09:32:48AM -0700, Johnathan Corgan wrote: > I was Googling around on constant modulus stuff and came across the > following paper: > > http://www.ee.ucl.ac.uk/lcs/papers2002/LCS133.pdf
Thanks for the pointer. > But it wasn't the CMA stuff that caught my attention, it was the > description of converting a transversal FIR filter from a MAC function > to an adder by going into the logarithmic domain, delay/adding the > (log)weights, then exponentiating. This appeared to be done with fixed > point integers. The log operation was approximated. > > I'm not all that familiar with optimized floating point (it just works) > so I don't know how long SSE, etc. multiplies take, but I am interested > in knowing whether there is merit to this transform in time and MIPS for > a float based signal stream on a x86 processor such as we use in GNU Radio. Floating point is very fast. We can do pretty close to 1 MAC / clock cycle on Pentium 3/4/M, Athlon and AMD-64. > -Johnathan, posting from sunny, 109F Phoenix "but it's a dry heat" AZ :-( Eric _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
