Generating signal with several frequencies - Timing issues

Hi
I use Labview 7.1.
I am trying to generate a signal composed of 1000 different frequencies.
For this purpose I am using the Multitone Generator VI .
My problem is that the generating process is too long for my real-time
application.
Is there any way to accelerate (optimize) this process?
I think about several options, such as:
Using more powerful computer (multicore)
Making the process parallel (is it relevant
for Labview7.1?)
Changing VI's properties (priority etc..)
Please advice
Amir

Hi,
Attached my problem.
I am trying to generate signal with 100 frequency component (100 different sine waves).
According to the timers it is taking 87mSec to produce the signal which length is 1 second.
In my project, I need to generate 1000 frequency components. And also 20 channel of this kind.
So it is clear that i will not be able to achieve the timing requirements
(It will take more than 1 second to generate a signal of 1 second)
What can you advise me ?
Thanks
Amir
Attachments:
Generate_100_freq_signal.jpg ‏156 KB

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Jeff Bohrer wrote:
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I am sampling at 100 times the sine wave's frequency and 200 times the square wave's frequency. Increasing the sampling rate completely solves my problem. But since I am acquiring several other inputs, I cannot afford a sampling rate higher than 5kHz.
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Preetham1 wrote:
Hello srikrishnaNF,
Thanks for the solution. But the issue is I just want to append one cycle of a1,f1 and one cycle of a2, f2. f1 and f2 could be DBL. Let me know if you have a solution. I shall appreciate it.
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Attachments:
Build Waveforms.png ‏23 KB

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I am trying to use NI-USB 6259(BNC) to send Pulse signals to conduct position control of a servo motor with labview. The position control of servo motor follows these rules:
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0-1
923
1
923hz
1-2
3540
0
3540hz
2-3
1751
1
1751hz
3-4
2663
0
2663hz
4-5
353
0
353hz
5-6
1017
1
1017hz
6-7
3436
1
3436hz
7-8
302
0
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1
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9-10
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Solved!
Go to Solution.
Attachments:
Counter - Finite Output.vi ‏57 KB
Finite output.png ‏13 KB

Hi aacuna,
Thank you for your reply!
I already checked that article. The frequency in that Vi can change dynamically, but the method of adjusting the frequency is ‘manual’ .Below is the front panel of that Vi. When the Vi is running we can change the frequency by press the button.
Time(s)
Frequency
0-1
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1751hz
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7-8
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8-9
1513hz
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Thank you！

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[email protected]

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Attachments:
frequencytest.vi ‏21 KB

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     com.crystaldecisions.reports.reportengineinterface.a.a.b.a(Unknown Source)
     com.crystaldecisions.reports.sdk.ReportClientDocument.open(Unknown Source)
     com.sysarris.aris.crystalreports.RepServlet.generateReport(RepServlet.java:65)
     com.sysarris.aris.crystalreports.RepServlet.doPost(RepServlet.java:40)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:763)
     javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
     weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:225)
     weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:127)
     weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:272)
     weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:165)
     weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3153)
     weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
     weblogic.security.service.SecurityManager.runAs(SecurityManager.java:121)
     weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:1973)
     weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:1880)
     weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1310)
     weblogic.work.ExecuteThread.execute(ExecuteThread.java:207)
     weblogic.work.ExecuteThread.run(ExecuteThread.java:179)
Can you please suggest any work around for this?

I'm not referring to Servlet threading issues.
I'll clarify.
You have two threads, both entering ReportClientDocument.open(...) method.
Thread 4 is waiting to acquire 'com.crystaldecisions.reports.queryengine.av@15214b9'
Thread 0 is waiting to acquire ''com.crystaldecisions.reports.queryengine.av@12e0415'
So I'm thinking ??? are they the same objects?
My specific question concerning the ReportClientDocument is that both are calling open - i.e., trying to open a new report. You wouldn't be trying to open different reports using the same ReportClientDocument - so was wondering if you've cached the RCD and trying to open two different reports at the same time on the same instance via different threads.
You'd normally tie a ReportClientDocument instance to a HTTP Session, to ensure each user gets their own copy.
Sincerely,
Ted Ueda

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