Microwave Engineering Mid - I, September - 2014

1.Generally the waveguides are preferred below the frequencies of
  • 100GHz
  • 50GHz
  • 10GHz
  • 1GHz
Answer: D
2.In IEEE standards X-Band Limit is
  • 8 – 12.5GHz
  • 12.5- 18GHz
  • 3.9 - 8GHz
  • 1.1 – 1.7GHz
Answer: A
3.The unitary property of [S] helps to check the
  • Power balance of lossless structure
  • Frequency of lossless structure
  • Impedance of lossy structure
  • Power balance of lossy structure
Answer: A
4.Dominant mode in rectangular waveguide is
  • TE10
  • TM10
  • TE11
  • TM11
Answer: A
5.The electric field and magnetic field inside the waveguide can be determined by solving from which of the following equations subject to the appropriate boundary condition
  • Thevenin’s
  • Norton’s
  • Faraday’s
  • Maxwell’s
Answer: D
6.Which one of the following modes does not exist in waveguides
  • TE
  • TM
  • TEM
  • NONE
Answer: C
7.The ohmic loss in the strip line is due to
  • Inductance
  • Dielectric
  • Capacitance
  • Conductivity
Answer: D
8.One of the following is Ferrite
  • MnFe2O2
  • Mn2FeO2
  • ZnFe2O
  • ZnFe2O3
Answer: A
9.Relationship between phasevelocity and Groupvelocity is
  • Vp Vg = C2
  • Vp /Vg = C2
  • Vp C2 = Vg
  • None
Answer: A
10.E-Plane Tee is also called as
  • Voltage Junction
  • Power Junction
  • Current Junction
  • Impedance Junction
Answer: A
11.________________Mode exists in TM wave of rectangular waveguide as dominant mode.
Answer: TM11
12.The diagonal element of the scattering matrix are _________________co-efficient.
Answer: REFLECTION
13.When Microwave signal follow the curvature of the earth is known as ______________
Answer: Ducting
14.Wave impedance for TM wave in rectangular guide in ZTM_______________________
Answer: ZTM=η/√1-(λ0/λC)2
15.The sum of the products of each term of any row or column of ‘S’ matrix multiplied by its complex conjugate is _____________________property.
Answer: UNITARY
16.Cut-off wavelength(λc) of a wave guide is_____________
Answer: λc = 2ab/(m2b2+n2a2)½
17.The characteristic impedance of micro strip is Z0_____________________if w>>h
Answer: Z0=377/√εr.h/w
18.The Helm holts wave equation for TE & TM wave travelling in ‘Z’ direction of a wave guides are___________________& ___________________
Answer: Δ2Hz=0,Δ2Ez=0
19.The mode of propagation for micro strip line is__________________
Answer: QUASI TEM
20.When a metallic cylindrical post is introduced into the broader side of a waveguide which is extended only a short distance (<λ/4) into the wave guide it behaves as ___________________ in nature.
Answer: CAPACITIVE