Electrical Engineering (EE) Exam  >  Electrical Engineering (EE) Questions  >  A mixer stage has a noise figure of 20 dB. Th... Start Learning for Free
A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input is
  • a)
    11.07
  • b)
    18.23
  • c)
    56.43
  • d)
    97.38
Correct answer is option 'A'. Can you explain this answer?
Verified Answer
A mixer stage has a noise figure of 20 dB. This mixer stage is precede...
The required answer is 7.94 + (100-1)/31.62 = 11.07.
View all questions of this test
Most Upvoted Answer
A mixer stage has a noise figure of 20 dB. This mixer stage is precede...
Given data:

Noise figure of mixer stage = 20 dB

Noise figure of amplifier stage = 9 dB

Power gain of amplifier stage = 15 dB

To find: Overall noise figure referred to the input

Calculation:

1. Calculation of noise factor (F) and noise figure (NF) of the amplifier stage

Given data:

Noise figure of amplifier stage (NF1) = 9 dB

Using the formula,

NF1 = 10 log10 (F1 + 1)

9 = 10 log10 (F1 + 1)

F1 + 1 = antilog (9/10)

F1 + 1 = 7.94

F1 = 7.94 - 1

F1 = 6.94

2. Calculation of noise factor (F) and noise figure (NF) of the mixer stage

Given data:

Noise figure of mixer stage (NF2) = 20 dB

Using the formula,

NF2 = 10 log10 (F2 + 1)

20 = 10 log10 (F2 + 1)

F2 + 1 = antilog (20/10)

F2 + 1 = 100

F2 = 100 - 1

F2 = 99

3. Calculation of overall noise factor (F) and noise figure (NF) referred to the input

Using the formula,

F = F1 + (F2-1)/G1

Where,

G1 = 10^(power gain of amplifier stage/10)

= 10^(15/10)

= 31.62

F1 = 6.94 (calculated in step 1)

F2 = 99 (calculated in step 2)

F = 6.94 + (99-1)/31.62

= 6.94 + 3.10

= 10.04

Using the formula,

NF = 10 log10 (F)

= 10 log10 (10.04)

= 10.07 dB

Therefore, the overall noise figure referred to the input is 11.07 dB (option A).
Explore Courses for Electrical Engineering (EE) exam

Top Courses for Electrical Engineering (EE)

A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer?
Question Description
A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer? for Electrical Engineering (EE) 2024 is part of Electrical Engineering (EE) preparation. The Question and answers have been prepared according to the Electrical Engineering (EE) exam syllabus. Information about A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for Electrical Engineering (EE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer?.
Solutions for A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for Electrical Engineering (EE). Download more important topics, notes, lectures and mock test series for Electrical Engineering (EE) Exam by signing up for free.
Here you can find the meaning of A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer?, a detailed solution for A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer? has been provided alongside types of A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice A mixer stage has a noise figure of 20 dB. This mixer stage is preceded by an amplifier which has a noise figure of 9 dB and an available power gain of 15 dB. The overall noise figure referred to the input isa)11.07b)18.23c)56.43d)97.38Correct answer is option 'A'. Can you explain this answer? tests, examples and also practice Electrical Engineering (EE) tests.
Explore Courses for Electrical Engineering (EE) exam

Top Courses for Electrical Engineering (EE)

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev