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E4D12
What is the link margin in a system with a transmit power level of 10 W (+40 dBm), a system antenna gain of 10 dBi, a cable loss of 3 dB, a path loss of 136 dB, a receiver minimum discernable signal of -103 dBm, and a required signal-to-noise ratio of 6 dB?
Pick an answer to check it.
Answer: C. +8dB
Received signal = 40 + 10 - 3 - 136 = -89 dBm. Required level = MDS + S/N = -103 + 6 = -97 dBm. Margin = -89 - (-97) = +8 dB.
Tip: Margin = received minus required.