RADIO NAVIGATION
Summary / Notes
, Table of contents
Section 1 – Radio Navigation Basics
Basic Radio Principles… ............................................................. 2
VHF Direction Finding… .............................................................. 5
NDB and ADF. ........................................................................... 5
VOR and Doppler VOR ................................................................ 8
Distance Measuring Equipment (DME) ..................................... 10
Section 2 – Landing systems
Instrument Landing System (ILS) ............................................. 11
Microwave Landing System (MLS) ............................................ 12
Section 3 – Radar systems
Radar Principles….................................................................... 13
Ground Radar… ........................................................................ 14
Secondary Surveillance Radar (SSR)… ....................................... 15
Airborne Weather Radar (AWR) .............................................. 16
Section 4 – GNSS and PBN
Global Navigation Satellite Systems (GNSS) ............................. 17
Performance Based Navigation (PBN)… .................................... 19
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, Chapter 1 – Basic Radio Principles
Electron Flow
-Atom = central nucleus around which electrons orbit
-Electrons = negatively charged
-Protons = positively charged
-Electron flow = 2 atoms -> electron transfers from negative to positive one
Electrical Current
-AC = Alternating current
-DC = Direct current
-Pulsating = Varying current strength
-EMR = Electromagnetic radiation
Radio Wave Formula (c = f x λ)
-λ = Lambda = wavelength (m)
-f = Hertz = cycles per second (hz)
-c = velocity of propagation = 3 x 10^8 (m/s)
Equipment Frequencies
NDB 190 – 1750 kHz
Radio Spectrum
HF Communication 2 – 25 MHz
-VLF = 3 – 30 kHz ILS Marker 75 MHz
-LF = 30 – 300 kHz ILS Localizer 108 – 112 MHz
-MF = 300 kHz – 3 MHz VOR 108 – 118 MHz
-HF = 3 – 30 MHz VHF Communication 118 – 137 MHz
-UHF = 300 MHz – 3 GHz ILS Glide Slope 328.6 – 335.4 MHz
-SHF = 3 – 30 GHz DME 960 – 1215 MHz
-EHF = 30 – 300 GHz SSR/TCAS 1030 – 1090 MHz
MLS 5031 – 5091 MHz
Weather Radar 9375 MHz
Attenuation
-Meaning = reduction signal strength due to absorption/scattering/dispersion
-Geometrical dispersion = signal reduction as it spreads out over increasing area
Polarisation
-Magnetic field/ electric field = at right angles to each other and direction of motion energy
-Polarisation of radio wave = alignment of electric field
-LF/MF/HF = use horizontally polarized antennas
-High frequency communication = use vertically polarized antennas
-Different polarisation = cos angle between aerials = signal strength
-Circular polarisation = simultaneous horizontal and vertical polarisation
-H = magnetic wave
-E = electric wave
-TX = Transmitter
-RX = Receiver
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Summary / Notes
, Table of contents
Section 1 – Radio Navigation Basics
Basic Radio Principles… ............................................................. 2
VHF Direction Finding… .............................................................. 5
NDB and ADF. ........................................................................... 5
VOR and Doppler VOR ................................................................ 8
Distance Measuring Equipment (DME) ..................................... 10
Section 2 – Landing systems
Instrument Landing System (ILS) ............................................. 11
Microwave Landing System (MLS) ............................................ 12
Section 3 – Radar systems
Radar Principles….................................................................... 13
Ground Radar… ........................................................................ 14
Secondary Surveillance Radar (SSR)… ....................................... 15
Airborne Weather Radar (AWR) .............................................. 16
Section 4 – GNSS and PBN
Global Navigation Satellite Systems (GNSS) ............................. 17
Performance Based Navigation (PBN)… .................................... 19
1
, Chapter 1 – Basic Radio Principles
Electron Flow
-Atom = central nucleus around which electrons orbit
-Electrons = negatively charged
-Protons = positively charged
-Electron flow = 2 atoms -> electron transfers from negative to positive one
Electrical Current
-AC = Alternating current
-DC = Direct current
-Pulsating = Varying current strength
-EMR = Electromagnetic radiation
Radio Wave Formula (c = f x λ)
-λ = Lambda = wavelength (m)
-f = Hertz = cycles per second (hz)
-c = velocity of propagation = 3 x 10^8 (m/s)
Equipment Frequencies
NDB 190 – 1750 kHz
Radio Spectrum
HF Communication 2 – 25 MHz
-VLF = 3 – 30 kHz ILS Marker 75 MHz
-LF = 30 – 300 kHz ILS Localizer 108 – 112 MHz
-MF = 300 kHz – 3 MHz VOR 108 – 118 MHz
-HF = 3 – 30 MHz VHF Communication 118 – 137 MHz
-UHF = 300 MHz – 3 GHz ILS Glide Slope 328.6 – 335.4 MHz
-SHF = 3 – 30 GHz DME 960 – 1215 MHz
-EHF = 30 – 300 GHz SSR/TCAS 1030 – 1090 MHz
MLS 5031 – 5091 MHz
Weather Radar 9375 MHz
Attenuation
-Meaning = reduction signal strength due to absorption/scattering/dispersion
-Geometrical dispersion = signal reduction as it spreads out over increasing area
Polarisation
-Magnetic field/ electric field = at right angles to each other and direction of motion energy
-Polarisation of radio wave = alignment of electric field
-LF/MF/HF = use horizontally polarized antennas
-High frequency communication = use vertically polarized antennas
-Different polarisation = cos angle between aerials = signal strength
-Circular polarisation = simultaneous horizontal and vertical polarisation
-H = magnetic wave
-E = electric wave
-TX = Transmitter
-RX = Receiver
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