GATE EC 2014 Set 2 — Question 62
Go beyond PYQs with Success TrackerAI-powered personalised practice and doubt support. Unlimited practice on eligible plans; AI usage limits apply.NAT+2 / -0HardDSB-SC & SSBAnalog CommunicationsCommunicationsAM & FM Spectra
Communications → Analog Communications → AM & FM Spectra
Last updated
Question
In the figure, is the Fourier transform of the message signal where Hz and Hz. Given and , where . The cutoff frequencies of both the filters are .
The bandwidth of the signal at the output of the modulator (in Hz) is _____.

Correct answer
59.9 to 60.1
Solution
1.The message signal has a spectrum that is non-zero in the range .
2.Multiplying by shifts the spectrum to . The positive frequency components are in the range .
3.The High Pass Filter (HPF) has a cutoff frequency of . It passes frequencies greater than , which corresponds to the Upper Side Band (USB): .
4.This signal is then multiplied by . This shifts the USB spectrum by .
5.The difference frequency components are .
6.The Low Pass Filter (LPF) has a cutoff frequency of . Since Hz and , the baseband signal Hz passes through.
7.The bandwidth of the resulting signal is Hz.
Continue learning with Success Tracker
A step still unclear? Work through it with support
Use Success Tracker to ask about the reasoning, then try another GATE EC question to check your understanding.
AI-powered practice· Unlimited practice on eligible plans
- PYQs with solutions
- Attempt available previous-year questions, then compare your reasoning with the worked solution. Coverage varies by stream.
- Practice that adapts
- Choose a topic, work on weaker areas and bookmark questions to revisit. Your attempts feed your progress tracking.
- AI doubt support
- Ask follow-up questions about a step or concept while practising, instead of stopping at the final answer.
Unlimited practice is available on eligible plans. Free practice and AI usage have limits; check the current plan allowances before choosing.
This page stays readable without an account. AI responses can be wrong; check them against the solution and source material.
More questions on Analog Communications
2026 Set 1 Q22Consider a discrete memoryless source with an alphabet of four source symbols. is a…2026 Set 1 Q32A wireless digital transmission scheme is using -QAM over an additive white Gaussian noise…2026 Set 1 Q44A QPSK modulated signal from an additive white Gaussian noise (AWGN) channel is received with an…2026 Set 1 Q55Let the relevant bandwidth () of a digital communication system be and…2026 Set 1 Q57Consider a real, narrowband signal where the maximum…