Electronics and Communication Engg. Dept Second Year Subject : Communication Engg.
2 MARKS Q ES!"#$S
1. Define noise and state its different types. 2. What is meant by intermediate frequency? Give its typical values. 3. Write the equation for F.M and .M !ave. ". Define sensitivity and ima#e frequency related to radio receiver. $. %&plain base band transmission system. 'Dra! bloc( dia#ram of rmstron# method. ). Why is G* used in radio receiver? +. ,tate ideal and practical values of band!idth required for F.M. -. Define narro!band and !ideband FM. 1.. Define selectivity. 11. What is ima#e frequency re/ection? 12. Define frequency modulation. 13. What is 0,1? 1". Define trac(in#. 1$. What is modulation inde& of FM.? 1'. Define phase modulation. 1). What is pulse modulation?
1+. Write points of distinction bet!een M and FM. 1-. Define 2 M322M32WM. 2.. Define F.DM. 21. Modulation inde& of .M. 22. Modulation inde& of F.M. 23. Define noise fi#ure. 2". 4oise factor 2$. 4oise temperature. 2'. ,i#nal to noise ratio. 2). Define sensitivity5 selectivity and fidelity of radio receiver. 2+. %&plain pre6emphasis and de6emphasis. 2-. Distin#uish3 define bet!een 7DM and FDM. 3.. Dra! 1loc( dia#ram of 2. system. 31. What is quanti8ation? 32. What is quanti8ation noise? 33. %&plain samplin# theorem. 3". 1loc( dia#ram of super heterodyne receiver 3$. dvanta#e of 9F amplifier. 3'. 2rinciple of optical recordin# 3) What is multiple&in#? 3+. What is the Function of microphone and list the types of microphone. 3-. Why is mi&er used in FM receiver? ".. 9equirement of 2 system.
"1. dvanta#es of differential 2*M over 2*M. "2. Define directivity and efficiency of :oud ,pea(er. "3. %&plain tone control in detail. "". %&plain concept of ma#netic recordin#. "$. What is delta modulation? "'. %&plain !ith a neat bloc( dia#ram concept of 7DM "). Distin#uish bet!een M and FM. "+. Distin#uish bet!een FM and 2M. "-. Dra! the frequency spectrum M and FM !ave $.. ;o! do you calculate the b! of M and FM !ave. ;o! many sidebands are present in the spectrum of FM !ave. $1. What are baffles? $2. What are enclosures and its type? $3. What are !oofers5 t!eeters and squa!(ers?
C%A&!ER '
1. Define modulation? What are their types? %&plain the necessity of
modulation. 2. Derive the e&pression of carrier po!er5 po!er in sidebands5 total transmitted po!er and efficiency for .M si#nal. 3. Derive an e&pression for instantaneous value of M and e&plain frequency spectrum in M !ave. ". Dra! and e&plain M broadcast transmitter. $. Describe the !or(in# of balanced modulator also derive the e&pression of o3p volta#e of it. '. Define amplitude modulation and derive an e&pression for total po!er in amplitude modulated !ave in terms of modulation inde&. +. Dra! bloc( dia#ram of communication system and e&plain the function of each bloc(. -. Dra! amplitude modulated si#nal for m<$5 m<15 m=1. 1.. %&plain over modulation5 critical modulation5 under modulation and modulation inde&. 11. %&plain the concept of 0,15 >,1 and D,1,*. 12. What are the methods to suppress sidebands? 13. %&plain noise and its types. 1". %&plain phase shift method of #eneration of ,,1.
C%A&!ER 2
1. What are the methods of FM #eneration?
2. What is the band!idth required for FM. 3. *ompare .M5 F.M and 2.M modulation. ". What are the advanta#es and disadvanta#es of M and 2.M.%&plain modulation inde& of FM. $. *ompare narro!band and !ideband FM. '. Dra! frequency modulation alon# !ith neat dia#ram. ). Derive the equation for frequency modulated !ave. +. %&plain the terms pre6emphasis and de6emphasis.
C%A&!ER ( ) *
1. %&plain the terms related to radio receiver that is selectivity5 sensitivity and fidelity. 2. Dra! bloc( dia#ram of super heterodyne receiver. 3. What is the principle of G* .%&plain simple and delayed G*. ". %&plain simple diode detector. What are its limitations? $. Dra! bloc( dia#ram of FM receiver and e&plain its bloc(s. '. Dra! bloc( dia#ram of M receiver and 2. ,ystem. ). %&plain !or(in# of phase discriminator !ith circuit dia#ram. +. What are different ,,1 demodulators? %&plain any one. -. What is amplitude limiter? %&plain in detail. 1.. %&plain trac(in# errors and their types. 11. %&plain double spottin#. 12. Write a short note on G*.
13. Why >F frequency of "$$ (;8 has been selected. %&plain the term ima#e frequency.
C%A&!ER +
1. What are the different types of pulse modulation and state its advanta#es. 2. %&plain the concept of samplin# !ith neat dia#ram and e&plain samplin# theorem. 3. %&plain 2 M !ith dia#ram and also list its advanta#es and disadvanta#es. ". %&plain 2WM !ith dia#ram and also e&plain its advanta#es and disadvanta#es. $. What is pulse position modulation e&plain !ith dia#ram .;o! 22M is derived from 2WM. '. *ompare 2 M5 2WM and 22M. ). %&plain pulse code modulation !ith dia#ram. :ist its advanta#es5 disadvanta#es and applications. +. What is quanti8ation? -. What are quanti8ation errors and ho! they can be minimi8ed? 1.. %&plain delta modulation !ith neat dia#ram and list its advanta#es5 disadvanta#es and applications. 11. %&plain differential pulse code modulation !ith dia#ram.
C%A&!ER ,
1. Write short note on microphone and state its types.
2. %&plain :, and its types. 3. Dra! 2. bloc( dia#ram. ". %&plain carbon microphones. $. %&plain the principle of 7.0 si#nal #eneration. '. %&plain principle of optical recordin#. ). %&plain ma#netic tape recordin#. +. %&plain crystal microphones. -. %&plain baffles and enclosures. 1.. %&plain tone control.
