Hi Akanksha,
As per the updated syllabus of NEET UG 2019 the "communication systems" chapter is not included in the syllabus.
To be on the safe side, you can if you want, have a rough idea of what type of questions were asked under communication systems to atleast attempt the question incase it comes in the worst case scenario. Apart from that, as far as syllabus is concerned, communication systems is not included.
Hope this addresses.
Thankyou.
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