SUBJECT: ANTENNAS AND WAVE PROPAGATION 1. Define an antenna. Antenna is a transition device or a transducer between a guided wave and a free space wave or vice versa. Antenna is also said to be an impedance transforming device. 2. What is meant by radiation pattern? Radiation pattern is the relative distribution of radiated power as a function of distance in space .It is a graph which shows the variation in actual field strength of the EM wave at all points which are at equal distance from the
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US ARMY SIGNAL CENTER AND FORT GORDON PRINCIPLES OF RADIO WAVE PROPAGATION (SC:25C) EDITION DATE: FEBRUARY 2005 PRINCIPLES OF RADIO WAVE PROPAGATION Subcourse Number SS0130 EDITION B United States Army Signal Center and Fort Gordon Fort Gordon‚ Georgia 30905-5000 10 Credit Hours Edition Date: February 2005 SUBCOURSE OVERVIEW This subcourse is designed to teach the principles of radio wave propagation. The prerequisite for this subcourse is that you
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spreads across a medium (i.e.‚ air or water) as a mechanical longitudinal wave formed by pressure. A Mechanical longitudinal wave can also be called compression wave as it generates compressions and rarefaction when traveling through a medium. (Sound Is a Pressure Wave - Physics Classroom) The amplitude of a sound wave is the difference between the pressure of the undisturbed air and the maximum pressure caused by the wave. The Speed of sound deviates with the temperature‚ and density of the medium
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Introduction When companies begin to dominate the local market most of the time they would want to expand their horizons to the outside world where it could either make great strides or horrible losses.Corinthia Hotels is a Maltese founded company which began from a beautiful villa around 40 years ago in Malta that has now spread to Europe and north Africa in countries like Hungary‚Portugal‚Russia‚Czech republic and Libya.The success of this company has been brought about by careful analysis of
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Business 3.4 Internal constraints SWOT analysis SWOT analysis is a strategic planning method used by business to determine their strengths‚ weaknesses‚ opportunities and threats Businesses need to consider the financial and practical implications of any marketing mix that they want to implement. Very few businesses are able to operate a marketing mix without considering the costs involved. Typically costs can limit a business’s marketing mix in several ways. Promotion The first internal
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Stoneley-wave attenuation and velocity are sensitive to fracture and formation permeability‚ especially at low frequencies. Stoneley-wave velocity declines‚ and its attenuation increments‚ as permeability increments. Beginning endeavors (started in the 1970s) to get permeability information from Stoneley information was unsuccessful because neither the significant low-frequency instruments nor the proper handling techniques had been created. The parallel advancement of present day multi-pole array
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event affected New Zealand society Event: The Second Wave of Feminism The Second Wave of Feminism flourished in the 1970s as a result of gender discrimination against women and inequality in New Zealand. The issue of abortion was a significant social feature of the Second Wave of Feminism. Women felt that they needed to be represented politically to gain economic independence and raise awareness of important social issues. The Second Wave of Feminism had both short and long term political‚ economic
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Constructive waves deposit eroded material along the shore‚ which eventually builds up over time to form a beach. This occurs when the swash is stronger than the backwash‚ depositing more sediment than it transports elsewhere. Although beaches are a landform of deposition‚ they can also be considered to be a landform of erosion. When waves are huge and high‚ the backwash is more powerful than the swash‚ removing more loose material than it deposits. These types of waves are known as destructive waves. The
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Practise essay on Change In the novel The Wave by Morton Rhue we see change occur in this novel when a classroom experiment designed to show students how to make people change and conform their behaviour to fit certain rules. The classroom experiment that the teacher created was the catalyst that caused throughout the schools behaviour and the students behaviour and attitude. Robert Billings is a student who rarely pays attention in class and is always getting low marks and sleeping in Ben Ross’s
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motion‚ even when it is really cold. Gas Waves 10. Waves transfer _energy_ from place to place‚ and it spreads _out evenly_ from the source. 11. What is a mechanical wave? _A wave that requires a medium to travel through._ Example of a mechanical wave? _Sound_ An example of a non-mechanical wave (electromagnetic)? _Light_ 12. Label the following parts on a longitudinal wave: Compression a. Compression b. Rarefaction 13. In a longitudinal wave‚ the particles move Rarefaction parallel / perpendicular
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