simple qpsk question(modulation toolkit)

[nolsqn]

hi all i have some questions about modulation toolkit . In modulation toolkit the parameter "symbol rate", for example if i give the "modulate qpsk.vi" a symbol rate of 100k (along with all the other parameters) it generates a complex wave form with to,dt and Y in which the dt is 6.25 e-7. my question is that how this symbol rate is related to dt. and also the reset (boolean operator) in all the vi's of modulation tool kit how actually does it work ? meaning if i set it in true condition and place my prog in while loop does it reset for every iteration(by reset i mean to say does it take new valeus every time?? and also wat if i set the value to false how will it effect my vi ?? uptill now what i understand while in my vi when i set the condition to false , the result for the first time i run the vi are accurate but if i keep the same value for the second time i run the vi they are not ,but when again i change the input parameters they are again correct but if again i run it with the same value they are not . help plz!!!

[Bueller]

Hi nolsqn,

Thank you for posting on the discussion forums. I highly recommend that you take a look at the detailed context help of the modultion VI you are looking at as it has all the answers for the questions you are asking.

In case you don't know this, to get the contaxt help window in LabVIEW press ctrl+H.

A quick answer for your question, sample rate- symbole rate*samples/symbol

As far as using the the reset, yes the VI resets every iteration if you place it in a while loop with a true connected to it. If you are using one of the shipped examples, I recommend keeping the default values, but if you are facing a problem with a specific code, please post that code , and I will assist you on that.

Please let me know if you have any further questions

Best regards,

Faris A

[nolsqn]

thnx .....its now all clear to me..also can any one explain how sync indent works in the sync parameters. I read the help it said "sync indent (symbols) specifies the distance that the sync sequence is indented into the information block, that is, the number of symbols preceding the sync sequence that are demodulated. For example, a value of 10 indicates that the output bit stream will consist of 10 data symbols, followed by the sync sequence, followed by the remaining data symbols". So tell me if i am right if i have gurad 1 symbol, sync 10 symbols..and data of 2000 symbol so this value should be 2000.?????

thnx

ali  

[Bueller]

Hi Ali,

The indent value is something you specify to determine where you want your sync bit to be. It is by default set to zero, which means that the sync bits are at the beginning of your wave form. If you have 1 guard symbol,10 sync symbols , and  2000 data symbols, then having an indent of 2000 will give you the following output data sequence. 1 guard symbol and 1999 data symbols then 10 sync symbols then 1 data symbol.

I hope this exaplins it more to you.

Best Regards,

Faris A 

[nolsqn]

thnx all it clears a lot of confusions in my mind...thankyou very much ..