Hi rolando. I'll add a little to what Dan said in his mail. > Hello CASPER > > I have some doubts, and I hope you can help me understand. > > Regarding correlators: > > 1. What is the reason of using one Roach (exclusively) for F engine, and > one Roach (exclusively) for the X Engine, through one switch? >
The switch is used in correlators with a large number of inputs, that is, more than can fit on one Roach or ibob, or in applications where the X-engine is split over more than one device. The switch acts as a way to send parts of the spectrum to different x engines for correlation. As Dan says, you don't necessarily need a switch just for small systems that fit on one board. > 2. Why can not use the latest libraries to program the FPGA IBOB card? As dan says, the Virtex-II Pro is no longer supported by new Xilinx tools, and the Matlab/Simulink versions in use for the newest libraries are not compatible with older tools, so can't be used with them. > > 3. To build a correlator with IBOB's (8 input/two QuADC), what would be > the > advantages of using one IBOB to F engine, and one IBOB for X engine? Or > just one IBOB is enough? If it all fits on one board, then that is definitely easier. If it fits or not would depend on the bandwidth you need, the number of channels you use, and the number of bits used in the calculation, among many other factors. John > > Best Regards > > Rolando Paz >
