In the case of a 70 MHz IF carrier for a transponder bandwidth of 36 MHz, energy must lie...
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In the case of a 70 MHz IF carrier for a transponder bandwidth of 36 MHz, energy must lie between:
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Answer: B. 52 and 88 MHz
The IF carrier frequency is 70 MHz with a bandwidth of 36 MHz. The signal energy occupies a frequency range centered on the carrier, extending ±(bandwidth/2) on either side. Lower bound: 70 − 36/2 = 70 − 18 = 52 MHz. Upper bound: 70 + 36/2 = 70 + 18 = 88 MHz. Therefore, energy lies between 52 and 88 MHz.
Step-by-step Derivation:
Given:
- IF carrier frequency (fc) = 70 MHz
- Transponder bandwidth (BW) = 36 MHz
Frequency range calculation:
- Lower frequency limit = fc − (BW / 2) = 70 − (36 / 2) = 70 − 18 = 52 MHz
- Upper frequency limit = fc + (BW / 2) = 70 + (36 / 2) = 70 + 18 = 88 MHz
Answer: Signal energy occupies the range [52 MHz, 88 MHz]