Differences between RHC and control horizon in MPC

Question

I have used model predictive control strategy in order to optimize a linear discrete SISo model.

For example:

$x(t+1)=-2x(t)+4u(t)$

Where I want to regulate my state $x(t)$ at the desired point (a simple regulating problem).

In every step, I predict $20$ future samples such that MPC optimizes next $20$ time instances (prediction horizon$=20$) and obtains $20$ responses for control variable(control horizon $=20$) then based on RHC technique, I just apply $10$ samples to model. I know both control horizon and prediction horizon are $20$ samples. but what about applied samples ($10$ samples) what can I name my applied samples?

Answer 1

I found another term clearly to name control sequences in this case: manipulated control sequence means some consecutive sequences of decision variables which are ready to be applied to the system.

Answer 2

based on an article (Fig.2):

https://doi.org/10.3390/en11030631

control time steps is a word to define the time between control updates and iterative receding horizon optimization.