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Radio frequency technology:      
Digital modulation GPS RF datacommunication UMTS
EMW GSM Transmission lines WAP
GPRS Radio frequency Transmission lines topics WIFI-WLAN

Transmission lines  related subject: Antennas, Cabling theory, Electro magnetic waves, RF transformers, TDR Measurements, Waves (physics)
Ligne de transmission en Français, pdf-file
Antennas & Transmission Lines cables and waveguides, pdf-file
Transmission lines finite resistance in transmission lines, proximity effect in transmission lines, a physical phenomenon that cause opposing currents in adjacent wires to draw toward one another, the proximity effect is caused by changing magnetic fields and therefore does not occur for low frequency signals, a tip
Transmission line and termination Characteristic impedance of a coax cable and twin lead cable, balun, twisted pair, impedance matching, ppt file
Transmission lines pdf-file
Transmission lines pdf-file
Transmission lines The transmitter that generates the RF power to drive the antenna is usually located at some distance from the antenna terminals. The connecting link between the two is the RF transmission line. Its purpose is to carry RF power from one place to another, and to do this as efficiently as possible, pdf-file
Transmission lines a tip, animated
Transmission lines pdf-file
Transmission lines ppt file
Transmission lines ppt file
Transmission lines
Transmission lines definitions for transmission lines, microwaves, power flow on transmission lines, stub tuner matching, the SMITH chart, standing wave patterns, microwave measurements, scattering parameters and the S-matrix, waveguides and cavity resonators, microstrip
Transmission lines and antennas wave propagation, sound waves, light waves, electric field, speed of light, polarization, sky wave, ionosphere, refraction, transmission lines, tropospheric, reflection, terminating, standing waves, characteristic impedance, radiations, folded dipole, radiation resistance
Transmission lines and antennas electromagnetic fields and waves, cable, coax cable, twin
Transmission line transformers balun, Guanella 1:4 balun
Transmission line transformers pdf-file
Transmission lines tutorial explores transmission line behavior, educypedia
Transmission lines tutorials transmission line tutorials in pdf format, a tip
Transmission line impedances
Transmission lines properties Balance-to-ground, unbalanced transmission line, balanced transmission line, characteristic impedance, parallel conductor line, coaxial cable, Attenuation per unit length, Skin effect, attenuation per unit length, wave propagation velocity, electrical length
Transmission line theory pdf-file
Transmission sur lignes en Français, pdf file
Understanding Coaxial RF Transmission Lines by Measurement and Calculation Page 1

Characteristic impedance calculation:


Twincable (300 W ) Coax cable (50, 75, ..  Ohm )
  • L = 2.7 µH/m

  • C = 30 pF/m

  • Rs = 0.15 W/m

  • Rp = 1014 W/m

  • L = 0.5 µH/m

  • C = 47 pF/m

  • Rs = 0.002 W/m

  • Rp = 1012 W/m




Coax cable:

Zk = 138/er . log(D/d)  (W)

L = µrµ0/2p . ln(D/d)  (H/m)

C = 2pere0/ ln(D/d)  (F/m)

er: dielectric constant (relative permittivity) of the medium (if you don't know take 2.3, Polyethylene), air = 1

e0: permittivity of free space: 8.8542.10-12 F/m

d : the diameter of the inner conductor

D : the diameter of the outer conductor

µ0: Permeability of a vacuum: 4xp×10-7 H/m

µr: relative permeability of the medium: air = 1



Twin lead (balanced pair):

Zk = 276/er . log(2a/d)  (W)

L = µrµ0/p . ln(2a/d)  (H/m)

C = pere0/ ln(2a/d)  (F/m)

µr: relative permeability of the medium


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Last updated on: 2011-01-02 | Copyright © 2011-2013 Educypedia.