As per the new syllabus notified by CBSE in June 2014. Some new topics have been added to class-12 Physics in the chapter Communication Systems. The new topics are not given in NCERT text book for physics.
CBSE has issued a separate study material for these new topics. Students are advised to go through the new Supplementary Material for Class-12 Physics Here.
The Topics added are :
- INTERNET
- MOBILE TELEPHONY
- Global Positioning System
Unit X: Communication Systems (10 Periods and 10 Marks)
Elements of a communication system (block diagram only);
Elements of a communication system (block diagram only);
bandwidth of signals (speech, TV and digital data);
bandwidth of transmission medium.
Propagation of electromagnetic waves in the atmosphere,
sky and space wave propagation,
satellite communication.
Need for modulation, amplitude modulation and frequency modulation,
advantages of frequency modulation over amplitude modulation.
Basic ideas about internet, mobile telephony and global positioning system (GPS) (NEW)