Digital Signal Processing
Discuss the relations of SNR, EVM, Q and RIN.
How are the SNR and the OSNR defined?
How is the SNR related to the Shannon limit?
Name the different processing steps which need to be done in an optical digital coherent receiver.
How can chromatic dispersion be compensated and what is the characteristic of the compensation filter?
Describe the impairments which should be mitigated by de-skewing and orthonormalization.
What are the origins of timing errors?
Name different timing recovery algorithms and explain the basic ideas.
Which effect should be equalized by polarization division de-multiplexing? How can this effect be mathematically described?
Describe the different techniques which are used for polarization division de-multiplexing. How do their cost functions look like?
