What is the sampling frequency used at the Receiver of DVB_T Signal. Can I increase/decrease the sampling frequency of Tx signal to detect the presence of TV signal

Dear support team member,

I am currently using DVB-T signal available using Simulink model I found in communication demos folder (Simulink model I found in http://www.mathworks.com/help/comm/examples).

I am collecting the samples from Tx Part. And analyzing the data for TV signal detection by increasing/deceasing signal to noise ratio. But, I have questions related to sampling frequency of DVB_T signal.

Question 1: How can I change the center frequency of DVB_T signal in the model (If so, am i need to change any other parameter in the Tx link to get the real time TV band signal).

Question 2: How do I change the sampling frequency of collected data after transmitter. And What is the formula to find out the sampling frequency.

I am grateful if you provide the answers to my questions.