Question Bank Electronics Communication

Week 1:

1 Differentiate between AM and FM.2 The carrier amplitude after amplitude modulation varies between 4V and 1V.Calculate depth of modulation.3 What do you meant by AGC?4 Define modulation index of AM and FM.5 How PM signal is generated?6 Define amplitude Modulation7 Define Modulation index and percent modulation for an AM wave.8 Define Low level Modulation.9 Define High level Modulation.10 Define image frequency11 Define Single sideband suppressed carrier AM.12 Define AM Vestigial sideband.13 What are the advantages of single sideband transmission?14 Define frequency deviation.15 State Carson rule.16 Define Deviation ratio.17 What are the disadvantages of conventional (or) double side band full carriersystem?18 Define image frequency rejection ratio.19 Define Heterodyning.20 Distinguish between low level and high level modulatio21 With a neat block diagram explain generation of AM using DSB22 Explain in detail about the generation of SSB?23 Explain in detail about AM detector.24 Draw the circuit diagram of Foster seely discriminator and explain its working.25 Discuss the indirect method of generating the FM.26 Explain the generation of AM using DSBSC.27 Explain Armstrong method of generating FM.28 Explain the generation of PM.30 Explain in detail the demodulation of PM.31 How to achieve threshold reduction in FM receiver?32 What is meant by FOM of a receiver?33 What is extended threshold demodulator?34 Draw the Phasor representation of FM noise.35 Define pre-emphasis and de-emphasis.36 What is the need for performing pre-emphasis and de-emphasis in FM?37 What is the SNR for AM with small noise case?38 What is threshold effect with respect to noise?39 Define SNR.40 Define CSNR.41 Discuss the factors that influence the choice of intermediate frequency in a radio receiver.42 What are the advantages of superhetrodyne receiver?43 Explain the working of Superheterodyne receiver with its parameters. 44 Discuss the noise performance of AM system using envelope detection. 45 Compare the noise performance of AM and FM systems. 46 Explain the significance of pre-emphasis and de-emphasis in FM system? 47 Derive the noise power spectral density of the FM demodulation and explain its performance with diagram. 48 Draw the block diagram of FM demodulator and explain the effect of noise in detail. Explain the FM threshold effect? 49 Derive the expression for output signal to noise for a DSB-SC receiver using coherent detection.