hi folks,

I need sum help regarding multirate systems.
I am currently working on a project where we r developing a Transfer
Function model for Kalman Filter (Actually EKF). We have developed a
Kalman Filter for Avionics System of an autopilot.
In this filter we have GPS (measurements for KF) running at 5Hz and
inputs that is accelerometers and rate gyoros (INS) at 25 Hz. KF
operates at freq of 25 Hz.
Now we have developed a TF model for GPS update (at 5 Hz) inside KF and
TF model for numerical integration (at 25 Hz). The output of GPS update
is fedback to the numerical integration. Now to capture this in terms
of TF I need to take care of these mutirate systems.
Can anybody please guide me in this ..

thx and regards
Sumit