Quiz 13: Wave Propagation

Which of the following laws states that an electric current or a changing electric field produces a magnetic field? A.Maxwell's law B.Ampere's law C.Gauss's law D.Faraday's law

If an electromagnetic wave were radiated equally in all directions from a point source in free space,what would result? A.Spherical wavefront B.Electric field C.Radio wave D.Polarization

_____________ occurs when waves pass from a medium of one density to another medium with a different density. A.Radiation B.Reflection C.Refraction D.Reception

Which of the following is (are)the result of the interaction of changing electric and magnetic fields? A.Satellite communication B.GPS satellites C.Wave propagation D.Radio waves

What is it called when the azimuth and elevation angles for the Earth station antenna must be calculated so that the correct satellite can be seen? A.GPS B.Look angle C.Footprint D.Frequency-division multiple access

What type of orbit do geostationary orbits use? A.Equatorial orbit B.Polar orbit C.Inclined orbit D.Subsatellite orbit

A(n)___________ is an electronic system performing reception,frequency translation,and retransmission. A.antenna B.transponder C.attitude control D.downlink

What type of diversity reception is comprised of two or more receiving antennas separated by 50 wavelengths or more? A.Angle B.Polarization C.Frequency D.Space

The greater the bandwidth,the greater the problem with ________________. A.phase distortion B.refraction C.tropospheric scatter D.fading

What has a strong effect on ground waves? A.Refraction B.Seawater C.Changes in terrain D.Seasonal changes

What principle states that each point on a spherical wavefront may be considered as the source of a secondary spherical wavefront? A.Faraday's B.Huygens's C.Ohm's D.Maxwell's

What is the refracting and reflecting action of the ionosphere and the ground called? A.Skipping B.Multipath reception C.Radio horizon D.Shadow zone

Skip distance is affected by the degree of _________________. A.ionic recombination B.radiation C.ionization D.solar disturbance

When is the degree of ionization greater? A.Winter and nighttime B.Summer and daytime C.Winter and daytime D.Summer and nighttime

The highest frequency that is returned to Earth when transmitted vertically under given ionospheric conditions is called the ____________. A.critical angle B.maximum usable frequency C.critical frequency D.optimum working frequency

Ionospheric storms often cause radio communications to become ____________ A.erratic B.optimum C.electromagnetic D.radiated

Which one of the following predicted the existence of electromagnetic waves and proposed that visible light was a form of electromagnetic energy? A.Hans Christian Oersted B.Michael Faraday C.James Clerk-Maxwell D.André Ampère

What type of information does Global Positioning System (GPS)provide? A.Pinpoint geographic locations B.Multipath transmissions C.Converts energy from one form to another D.Sky-wave communication

What type of system allows multiple inexpensive stations to be linked to a large,central installation? A.Sirius B.Earth station C.Very small aperture terminal (VSAT) D.Ultrasmall aperture terminal mobile satellite (MSAT)

Which of the following is used to provide a performance measure for different satellite Earth stations? A.Uplink budget B.Downlink budget C.Satellite link budget D.Figure of merit

Reception of the Sirius Satellite Radio signal is made possible using antennas,special chip sets,and _______________. A.attitude controls B.diversity receivers C.transducers D.insulators

What is the area called between the point where the ground wave is completely dissipated and the point where the first sky wave returns,no signal will be heard? A.Skip zone B.Skip distance C.Critical angle D.Ionosphere

Frequency blackouts are closely related to certain types of ____________. A.sunspot activity B.turbulence C.fading D.energy

Where would tropospheric scatter provide reliable long-distance communication links? A.Deserts B.Small cities C.Suburban areas D.Metropolitan centers

A satellite communication system consists of an uplink,a downlink,and a(n)_______________. A.apogee B.electromagnetic field C.perigee D.orbiting satellite