I am a beginner again to signal processing, I did my degree over ten years ago, and I am relearning all my signal processing stuff.
I am a software developer by trade but now I am looking at some LTE PHY signal processing.
I am trying to understand how QPSK signals get recovered in LTE. As I understand things, the I/Q signal is passed through a low pass filter, which results in a sort of NRZ complex waveform.
However if I try to get a constellation diagram of this data it is a mess. So how do I recover this LPF baseband to see the constellation diagram?
All I get by Google is 'NRZ' or 'Zero-forcing' or 'DC offset'. I am awaiting my LTE matlab toolbox, but I should be able to recover the I/Q right? Do I need to do some sort of convolution?