Verify mobile number in custom form

Hi, first: Thanks for that great plugin! Doing everything well, but i need a special case:

I execute the php with

global $sms;
$sms->to  = array( $myVariable );
$sms->msg = "Test";
$sms->SendSMS();

The Problem is, that $myVariable coming from an input field of the same php file. So i have to pass that with jQuery to that PHP variable!?
Do you have any suggestions for that case?

Or do you have another solution for verify the mobile number inside an custom form?