Add DSP investiagtion plan.

applications/lofar2/model/pfb_os/dsp_study_erko.txt

@@ -1704,6 +1704,27 @@ Appendix B: Teaser talk: Oversampled polyphase filterbank (OPFB)
 11 References: HARRIS, CROCHIERE
 
 
+Appendix C: DSP investigation plan (RTSD-111)
+
+As RTSD team we want to have knowledge of advanced DSP like oversampled PFB,
+so that we can apply it in future projects.
+As SBe manager I want have a clear plan for investigation work, so that I know
+what I can expect as result and regarding costs.
+
+Acceptation criteria:
+
+  * identify DSP investigation topics:
+    - general: filtering, DFT
+    - filterbank: multirate, critically sampled PFB, perfect reconstruction,
+      oversampled PFB
+    - transient detection: Hilbert transform, analytic singal, half band
+      filters, all pass filters
+  * define end result (e.g. summary report in Confluence, Teaser talk)
+  * aim at about 250 hours work in 3 sprints (= 9 weeks ~= 20 story points)
+
+Definition of done: When plan is clear
+
+
 
 https://learning.anaconda.cloud/
 https://realpython.com/python-scipy-fft/