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Wireless Communications Principles and Practice - Chapter 4: Mobile Radio Propagation Large-Scale Path Loss

Wireless Communications Principles and Practice - Chapter 4: Mobile Radio Propagation Large-Scale Path Loss Introduction, Electromagnetic Spectrum, Electromagnetic Waves; Speed, Wavelength, Frequency; Electric and Magnetic Fields. | Wireless Communications Principles and Practice Chapter 4: Mobile Radio Propagation: Large-Scale Path Loss Doan Thi Thu Ha Vietnam National University of Agriculture Introduction • Radio waves are one form of electromagnetic radiation • Electromagnetic radiation has a dual nature: – In some cases, it behaves as waves – In other cases, it behaves as particles (photons) • For radio frequencies the wave model is generally more appropriate • Electromagnetic waves can be generated by many means, but all them involve the movement of electrical charges Electromagnetic Spectrum wavelength Electromagnetic Waves • Electromagnetic transmissions move in space as Transverse waves • Waves are characterized by frequency and wavelength v f Speed, Wavelength, Frequency • Light speed = Wavelength x Frequency = 3 x 108 m/s = 300,000 .