110 #5

Front 1

Formula used to describe the relationship between the angle of incidence and refraction, when referring to lights or waves passing through a boundary between two isotrophic media, such as water, glass, or air.

Back 1

Snell's Law

Front 2

Interference generated by natural phenomena such as thunderstorms, snowstorms, cosmic sources, and the sun.

Back 2

Natural Interference

Front 3

A german theoretical physicist whose discovery of quanta won him the Nobel Prize in Physics in 1918

Back 3

Max Planck

Front 4

The value of the divergence of the magnetic field in electrostatics.

Back 4

Zero

Front 5

Vector operator that describes the infinitesimal rotation of a vector field (magnetic field or electric field) in three dimensional Euclidean space.

Back 5

Curl

Front 6

States that both conduction current and displacement current acts as a source of magnetic field.

Back 6

Maxwell's 4rth Law

Front 7

It is located between the troposphere and the ionosphere. The temperature throughout this region is considered to be almost constant and there is little water vapor present.

Back 7

Stratosphere

Front 8

A scottish scientist in the field of mathematical physics. Formulated the classical theory of electromagnetic radiation, bringing together for the first time electricity, magnetism, and light as different manifestations of the same phenomenon.

Back 8

James Clerk Maxwell

Front 9

None of the field exists in the direction of propagation.

Back 9

Transverse electric and Magnetic Field

Front 10

The distance from the transmitter to the point where the sky wave is first returned to earth.

Back 10

Skip Distance

Front 11

Frequencies above 300 Ghz. Currently the only communication in this range in for research and experimental activities.

Back 11

Submillimeter

Front 12

A hollow metal conducting pipes designed to carry and constrain the electromagnetic waves of a microwave signal.

Back 12

Waveguide

Front 13

Latin for swift, the constant c in the speed of light.

Back 13

Celeritas

Front 14

Known as Maxwells 4rth equation

Back 14

Ampere-Maxwell Law

Front 15

Analysis used when dealing with microwave frequencies.

Back 15

Wave angles

Front 16

Part of klystron that is long enough so that the accelerated electrons catch up with electrons that were accelerated at an earlier time, forming "bunches" longitudinally along the beam axis.

Back 16

Drift space

Front 17

He discovered maxwells 3rd equation.

Back 17

Michael Faraday

Front 18

Fading resulting from the multipath propagation is variable with frequency since each frequency arrives at the receiving point via a different radio path. When a wide band of frequencies is transmitted simultaneously, each frequency will vary in the amount of fading.

Back 18

Selective fading

Front 19

The bending of the wave path when the waves meet an obstruction.

Back 19

Diffraction

Front 20

Apparent change in frequency or pitch when a sound source moves either towards or away from the listener, or when the listener moves either toward or away from the sound source.

Back 20

Doppler Effect

Front 21

Basically a voltage variable capacitor. When a reverse bias is applied to the diode. It acts as a capacitor. Its capacitance depends upon the value of the reverse bias.

Back 21

Varactor diode

Front 22

It occurs when high energy ultraviolet light waves from the sun enter the ionospheric region of the atmosphere, strike a gas atom, and literally knock an electron free from its parent atom.

Back 22

Ionization

Front 23

Waves that travel along the contour of the earth by diffraction.

Back 23

Microwave

Front 24

Known as maxwell's 1st equation.

Back 24

Gauss's Law of electricity

Front 25

A microwave tube which is a combination of a simple diode vacuum tube with built in cavity resonators and an extremely powerful permanent magnet.

Back 25

Magnetron

Front 26

Meaning of TRAPPAT

Back 26

Trapped Plasma Avalanche Triggered Transit

Front 27

Opposite of ionozation, that is, the free ions combine with positive ions to return to their original neutral atom state.

Back 27

Recombination

Front 28

Zone of silence between the point where the ground wave becomes too weak, for reception and the point where the sky wave is first returned to Earth.

Back 28

Skip zone

Front 29

Also called as compression waves.

Back 29

Longitudinal waves

Front 30

Frequencies above 1GHz called?

Back 30

Microwave Frequencies

Front 31

Often called the ionospheric wave is radiated in an upward direction and returned to Earth at some distant location because of refraction from the ionosphere.

Back 31

Sky Wave

Front 32

Combination of a receiver and a transmitter operating on separate frequencies.

Back 32

Repeater

Front 33

A diode compressed of a piece of semiconductor material and a fine wire that makes contact with the semiconductor material. Also calledbas crystal diode.

Back 33

Point-Contact Diode

Front 34

Term added by Maxwell in Ampere's Law to fix capacitor problem.

Back 34

Displacement Current

Front 35

A type of wave propagation that travels in a straight line directly from the transmitting antenna to the receiving antenna. Often called line-of-sight communication.

Back 35

Direct Wave Radio Signaling

Front 36

Use to minimize multipath fading. Two or more receiving antennas are spaced some distance apart. Fading does occur simultaneously at both antennas, therefore, enough output is almost always available from one of the antennas to provide useful signal.

Back 36

Space Diversity

Front 37

A special PN-Junction diode with an intrinsic layer between the P and N sections.

Back 37

PIN Diode

Front 38

It occurs when a transmitted signal divides and takes more than one path to a receiver and some of the signals arrive out of phase, resulting in a weak or fading signal.

Back 38

Multipath Fading

Front 39

The change in direction of a wavefront at an interference between two different media so that the wavefront returns into the medium from which it originated.

Back 39

Reflection

Front 40

Waves that travel at right angles to the direction of propagation

Back 40

Transverse Wave

Front 41

Use to minimize multipath fading. Two transmitters and two receivers are used, each pair tuned to a different frequency, with the same information being transmitted sinultaneously over both frequencies.

Back 41

Frequency Diversity

Front 42

Speeding up and slowing down of the electron beam in klystron.

Back 42

Velocity Modulation

Front 43

Type of loss due to the spreading out of the wavefront as it travels away from the transmitter. As the distance increases, the area of the wavefront spreads out.

Back 43

Free Space Loss

Front 44

Refers to the emission or ehection of electrons from the surface of generally a metal in response to incident light. Energy contained within the incident light is absorbed by electrons within the metal, giving electrons sufficient energy to be "knocked" out of, that is, emitted from, the surface of the metal.

Back 44

Photoelectric Effect

Front 45

A microwave a vacuum tube using cavity resonators to produce velocity modulation of an electron beam that produces amplification.

Back 45

Klystron