Setting symbol rate and sampling frequency for a carrier in Simulink

Trying to create a simple model using three QPSK carriers at varies center frequencies. I would like to individullay set the symbol rate for each carrier but cant figure out how to do that. What parameter controls the width (symbol rate) of the carrier? Also am trying to increase the simulation bandwidth to 128 but it stays at 32 Hz. The first block (random integer) is at sample time of 1/128, the next sample-hold is at 1/2 and the frequency shifts for each carrier are at -4, 0 and +4 Hz. So my question is how to set both the simulation badwidth and the symbol rate of each of these signals. Thanks.

Answer 1

[Devineni Aslesha]

The symbol rate of each of the given signals depends on the Sample time parameter in Random Integer Generator block. However, to get the simulation bandwidth of 128 Hz, the Sample time parameter of Zero-Order Hold block should be set to (1/128)/2. Since the Sample time parameter of Zero-Order Hold block is set to 1/2 as mentioned in the question, the Sample time of each symbol is taken as 1/2 instead of 1/128.