I do it, But the problem is not resolved
I set the step_time=1p or 10p or 100p but The result was not changed!!!
also I set the initial point as follow :
.ic nco=.9 vctrl=.9
and the problem is still there.
Changing just one parameter do not suffice; You should search for some guide to take the proper methodology for solving such a kind of problem like that:
Unfortunately, I do not have SPICE installed on my PC, but despite that, as you informed that you are a master student, it's an excellent opportunity to learn by doing. The most important general tips have been already provided, and from now on it's up to you make trial and error attempts in order to obtain the appropriate configuration parameters for YOUR particular case. Furthermore, you did not say what progress obtained by reading the document suggested above.
You use behavioral expression which include system variable "time".
Generally HB Analysis can't treat behavioral expression which include system variable "time".
This is true for $abstime in Verilog-A.
Try to use .SNOSC (Autonomous Shooting Newton Analysis) instead of .HBOSC (Autonomous HB Analysis).
And your circuit is no more than driven circuit.
You don't have to invoke autonomous analyses such as ".HBOSC" and ".SNOSC" at all.
Simply use ".SN".
If you use special system task, $cds_set_rf_source_info() in Verolog-A of Cadence Spectre,
you can treat behavioral expression which include $abstime in HB Analysis.
However this is not true for HB Analysis of Synopsys HSPICE.