Home > Community > Forums > RF Design > changing the simulator sampling time

Email

* Required Fields

Recipients email * (separate multiple addresses with commas)

Your name *

Your email *

Message *

Contact Us

* Required Fields
First Name *

Last Name *

Email *

Company / Institution *

Comments: *

 changing the simulator sampling time 

Last post Fri, Aug 10 2012 4:36 AM by Andrew Beckett. 1 replies.
Started by nevinalex1234 10 Aug 2012 04:14 AM. Topic has 1 replies and 1242 views
Page 1 of 1 (2 items)
Sort Posts:
  • Fri, Aug 10 2012 4:14 AM

    • nevinalex1234
    • Top 500 Contributor
    • Joined on Wed, Jul 18 2012
    • aluva, Kerala
    • Posts 26
    • Points 430
    changing the simulator sampling time Reply

     Hi

    I was trying to import cadence spectre values into matlab for analysis. I assumed that cadence samples a sinusoid for a given freq, for example if theoretically from transient signal of length upto 350ps i was expecting 1ps samples(sampled at 1000GhZ), ie 350 samples. But when i imported the values into MATLAB, there are hardly 80 odd values. The envelope of the wave resembles by cadence plot, but still i have lost a lot of values. Isnt the simulator trying to negate out some redundant values. 

    How do i change/freeze the simulator sampling time so that i recover the entire values ?

    • Post Points: 20
  • Fri, Aug 10 2012 4:36 AM

    Re: changing the simulator sampling time Reply

    Why do you think it should be sampled? spectre uses variable (adaptive) timesteps to ensure it follows signals to the desired accuracy - so there's nothing that would give you a regularly spaced timestep (by default) - why would it sample at 1000GHz unless you told it to?

    You can specify the strobeperiod parameter on the tran analysis (see "spectre -h tran") to specify that the simulator should write out the results at the specified interval - note that it also ensure that it solves at these strobeperiod timepoints - although it will also solve at intermediate points too if needed to preserve accuracy, but won't output them by default (unless you set strobeoutput=all - which is only available in relatively recent versions of MMSIM).

    Regards,

    Andrew.

    • Post Points: 5
Page 1 of 1 (2 items)
Sort Posts:
Started by nevinalex1234 at 10 Aug 2012 04:14 AM. Topic has 1 replies.