I have tried a code to compress a signal using Compressed Sensing(CS).
The input signal is $x$ and the compressed signal $y$ is given by :
$y=Φ*x$ where $Φ$ is the sensing matrix.
I have used the following matlab function to compute the energy of $x$ and the energy of $y$ .
energy_y = sum(y(1:192,:).^2);
The length of $x$ is 384 , and the length of $y$ is 192.
I found that the energy of $x$ is 446910 and the energy of $y$ is 77651282 .
Is it is reasonable to obtain higher energy for the output than the input?