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Simulators >> RF Simulators >> qpnoise/qpac never starts after successful qpss
https://designers-guide.org/forum/YaBB.pl?num=1367572991

Message started by Ruiyan on May 3^rd, 2013, 2:23am

Title: qpnoise/qpac never starts after successful qpss
Post by Ruiyan on May 3^rd, 2013, 2:23am

Hi Guys,

Just wondering what's happening here.
I'm trying to simulate a down conversion receiver with a blocker tone using qpss.
The qpss ran successfully. I'm expecting the qpac or qpnoise to follow that shortly.
However qpac/qpnoise will just sit there, never started even the first frequency point. no warning messages, no errors. I get the initial title for qnoise analysis and the Input Frequency Range = (...). but nothing after that!
Is this likely to be a memory problem?
I did get warnings of intensive swap activity and possible reduced performance.

Thanks.
Ruiyan

Title: Re: qpnoise/qpac never starts after successful qpss
Post by RFICDUDE on May 5^th, 2013, 4:37am

It is probably a memory problem.

If you have a terminal window open you can use the "top" linux command to see processes running. Use the "m" key to display processes according to memory usage. You will probably see the spectre process using most of the physical memory.

If it is a memory problem then you could try using the "swapfile" option for the QPSS/QPAC simulation. This will store information in a swapfile that is not needed for the current calculation. It doesn't slow down the simulation and it will free up memory for the simulator.

Title: Re: qpnoise/qpac never starts after successful qpss
Post by Ruiyan on May 7^th, 2013, 2:40am

Many thanks, RFICDUDE. I will try the swapfile option.