356799
A base band signal of \(3.5MHz\) frequency is modulated with a carrier signal of \(3.5GHz\) frequency using amplitude modulation method. What should be the minimum size of antenna required to transmit the modulated signal ?
1 \(42.8\;m\)
2 \(42.8\;mm\)
3 \(21.4\;mm\)
4 \(21.4\;m\)
Explanation:
Given \({f_c} = 3.5GHz,{f_m} = 3.5MHz\) Side band frequencies are \(f_{c}-f_{m} \& f_{c}+f_{m}\) which are almost \(f_{c}\left(\because f_{C}\right.\) is in giga range while \(f_{\mathrm{m}}\) are in mega range) \(\lambda=\dfrac{c}{f_{c}}\) (roughly for side bands too) Minimum length of antenna \(=\left(\dfrac{\lambda}{4}\right)\). \(\dfrac{c}{\left(f_{c}\right) 4}=\dfrac{3 \times 10^{8}}{3.5 \times 10^{9} \times 4} \quad(\because c=f \lambda)\) \( = 21.4\;mm\)
JEE - 2022
PHXII15:COMMUNICATION SYSTEMS
356800
The process of translating the information contained by the low base band signal to high frequencies is called
1 Detection
2 De modulation
3 Amplification
4 None of these
Explanation:
Conceptual Question
PHXII15:COMMUNICATION SYSTEMS
356801
Which of the following frequencies does not belong to FM broadcast?
1 \(64\,MHz\)
2 \(106\,MHz\)
3 \(99\,MHz\)
4 \(89\,MHz\)
Explanation:
The FM broadcast range is \(88 {MHz}\) to\(108 {MHz}\). So, \(64 {MHz}\) does not belong the FM broadcast.
356799
A base band signal of \(3.5MHz\) frequency is modulated with a carrier signal of \(3.5GHz\) frequency using amplitude modulation method. What should be the minimum size of antenna required to transmit the modulated signal ?
1 \(42.8\;m\)
2 \(42.8\;mm\)
3 \(21.4\;mm\)
4 \(21.4\;m\)
Explanation:
Given \({f_c} = 3.5GHz,{f_m} = 3.5MHz\) Side band frequencies are \(f_{c}-f_{m} \& f_{c}+f_{m}\) which are almost \(f_{c}\left(\because f_{C}\right.\) is in giga range while \(f_{\mathrm{m}}\) are in mega range) \(\lambda=\dfrac{c}{f_{c}}\) (roughly for side bands too) Minimum length of antenna \(=\left(\dfrac{\lambda}{4}\right)\). \(\dfrac{c}{\left(f_{c}\right) 4}=\dfrac{3 \times 10^{8}}{3.5 \times 10^{9} \times 4} \quad(\because c=f \lambda)\) \( = 21.4\;mm\)
JEE - 2022
PHXII15:COMMUNICATION SYSTEMS
356800
The process of translating the information contained by the low base band signal to high frequencies is called
1 Detection
2 De modulation
3 Amplification
4 None of these
Explanation:
Conceptual Question
PHXII15:COMMUNICATION SYSTEMS
356801
Which of the following frequencies does not belong to FM broadcast?
1 \(64\,MHz\)
2 \(106\,MHz\)
3 \(99\,MHz\)
4 \(89\,MHz\)
Explanation:
The FM broadcast range is \(88 {MHz}\) to\(108 {MHz}\). So, \(64 {MHz}\) does not belong the FM broadcast.
356799
A base band signal of \(3.5MHz\) frequency is modulated with a carrier signal of \(3.5GHz\) frequency using amplitude modulation method. What should be the minimum size of antenna required to transmit the modulated signal ?
1 \(42.8\;m\)
2 \(42.8\;mm\)
3 \(21.4\;mm\)
4 \(21.4\;m\)
Explanation:
Given \({f_c} = 3.5GHz,{f_m} = 3.5MHz\) Side band frequencies are \(f_{c}-f_{m} \& f_{c}+f_{m}\) which are almost \(f_{c}\left(\because f_{C}\right.\) is in giga range while \(f_{\mathrm{m}}\) are in mega range) \(\lambda=\dfrac{c}{f_{c}}\) (roughly for side bands too) Minimum length of antenna \(=\left(\dfrac{\lambda}{4}\right)\). \(\dfrac{c}{\left(f_{c}\right) 4}=\dfrac{3 \times 10^{8}}{3.5 \times 10^{9} \times 4} \quad(\because c=f \lambda)\) \( = 21.4\;mm\)
JEE - 2022
PHXII15:COMMUNICATION SYSTEMS
356800
The process of translating the information contained by the low base band signal to high frequencies is called
1 Detection
2 De modulation
3 Amplification
4 None of these
Explanation:
Conceptual Question
PHXII15:COMMUNICATION SYSTEMS
356801
Which of the following frequencies does not belong to FM broadcast?
1 \(64\,MHz\)
2 \(106\,MHz\)
3 \(99\,MHz\)
4 \(89\,MHz\)
Explanation:
The FM broadcast range is \(88 {MHz}\) to\(108 {MHz}\). So, \(64 {MHz}\) does not belong the FM broadcast.
