Should we upsample the channel when upsample the signal
In simulation, we do upsample to simulate the &quot;analog&quot; signal which is a continuous signal in reality but we represent it as a high-time-resolution in our digital/discrete simulation. When we upsample our data before going through the channel, we should also upsample the &quot;impulse response&quot; (IR) of the channel. It means that the timing-base of both signal and IR of channel must be same. For example, without upsampling, take for example of a channel with an IR of {4,0,0,3,0,1.5,0,0,0}. First, We may apply our signal (without upsampling) to this channel. Then, we upsample our signal with a factor of 2 and want to apply that to this channel again. this time we have to upsample our channel's IR with a factor of 2 just like the signal. So, the upsampled channel'IR would be: {4,0,0,0,0,3,0,0,1.5,0,0 ....}. So, the time-base or time-resolution of both signal and channel should be equal.