ATPL THEORY
Radio Navigation - Complete Summary
,Table of contents
Receiving a signal 4
Frequency spectrum 4
Determining a phase difference 5
Adding information to a wave 5
Sending binary information (1&0) 6
Emission classification 6
Polarisation 7
Dipoles 7
Different types of aerials 7
Bending waves 8
Attenuation 8
Skywaves 9
Ionospheric ducting 9
Doppler effect 9
Long range communications 10
Short range communications 10
NDB and ADF 12
Beat Frequency Oscillators (BFO) 12
Loop aerials 12
Relative bearing indicators (RBI’s) 13
Moving card ADF’s 13
Radio Magnetic Indicators (RMI’s) 13
Errors and accuracy 13
Range of a beacon 14
Types of NDB stations 15
NDB tracking 15
Homing to a beacon without allowing for drift 15
Intercepting a desired track 16
Conventional VOR 16
Doppler VOR 17
VOR Applications 17
Omni-Bearing Indicators 18
Radio Magnetic Indicators (RMI) 18
Horizontal Situation Indicators (HSI’s) 18
VOR Tracking 19
Errors and accuracy 19
Scalloping and site error 19
Power and range 19
Instrument Landing System (ILS) 20
Frequencies 20
Identification 20
Instrument displays 20
Localiser operation 21
Coverage 21
Glidepath 22
Coverage 22
Marker beacons 22
ILS tracking 23
Back course approaches 23
ILS Categories 23
Calculations 24
System monitoring 24
2
,Microwave landing system 24
The horizontal transmitter (azimuth) 25
The elevation transmitter 25
MLS aircraft equipment 25
Primary and secondary radar 25
Moving target indication (MTI) 27
En-route surveillance radar 27
Terminal surveillance radar 27
Approach surveillance radar 28
Airborne weather radar 28
Predictive wind shear (PWS) 29
Scanner Tilt Settings 29
Multi-scan radars 30
Mapping radar 30
Distance Measuring Equipment (DME) 30
DME Range and DME Derived Groundspeed 32
DME with ILS 32
Secondary surveillance radar (SSR) 33
Modes A and C transponder 33
Special codes 34
Mode S all-call 35
Satellite navigation systems 35
Navstar GPS 35
GLONASS 38
GALILEO 39
ABAS – Airborne Based Augmentation Systems 40
AAIM 40
Ground Based Augmentation Systems (GBAS) 41
Satellite Based Augmentation Systems (SBAS) 41
Navigational displays 42
FMS 43
Aircraft position 44
MCDU 44
Primary Flight Display (PFD) 44
Navigation display (ND) 45
Performance based navigation 45
Components of PBN 46
Linear and angular performance requirements 46
Continuity 46
Accuracy an integrity 46
Functionality 47
Required functions for PBN 48
Navigation specification levels 48
Developments in PBN 49
Airspace capacity 49
Components of PBN Routings 50
ARINC 424 51
RNP/RNAV Key Features 51
3
, General information
To produce radio waves, the following parts are necessary:
- Oscillating electrical current
- Aerial
Moving electrons in the aerial produce a changing magnetic field, moving away from the
aerial at the speed of light.
An aerial is a transductor: device that transforms energy from one type to another. In this
case: alternating current à free electromagnetic wave (RF – radio frequency).
Receiving a signal
When the changing electromagnetic waves pass a receiving aerial, the electrons in the
receiving aerial start to move in an identical way, compared to the transmitter.
- Frequency (Hz – Hertz). The number of complete cycles a wave makes during a
specific period of time. Usually measured in cycles per second.
- Speed of light = 3 x 10 m/s
8
The higher the frequency, the smaller the wavelength. In formula:
#
! = where λ is the wavelength (m), f is the frequency (Hz) and c is the speed of light
$
(m/s).
Wavelength is the physical distance travelled by a radio
wave during one cycle of transmission. It looks like:
Frequency spectrum
The frequency spectrum is based on the International Telecommunication Union (ITU)
classification.
A lot of questions on the official EASA exams are asked about the above table!
4
Radio Navigation - Complete Summary
,Table of contents
Receiving a signal 4
Frequency spectrum 4
Determining a phase difference 5
Adding information to a wave 5
Sending binary information (1&0) 6
Emission classification 6
Polarisation 7
Dipoles 7
Different types of aerials 7
Bending waves 8
Attenuation 8
Skywaves 9
Ionospheric ducting 9
Doppler effect 9
Long range communications 10
Short range communications 10
NDB and ADF 12
Beat Frequency Oscillators (BFO) 12
Loop aerials 12
Relative bearing indicators (RBI’s) 13
Moving card ADF’s 13
Radio Magnetic Indicators (RMI’s) 13
Errors and accuracy 13
Range of a beacon 14
Types of NDB stations 15
NDB tracking 15
Homing to a beacon without allowing for drift 15
Intercepting a desired track 16
Conventional VOR 16
Doppler VOR 17
VOR Applications 17
Omni-Bearing Indicators 18
Radio Magnetic Indicators (RMI) 18
Horizontal Situation Indicators (HSI’s) 18
VOR Tracking 19
Errors and accuracy 19
Scalloping and site error 19
Power and range 19
Instrument Landing System (ILS) 20
Frequencies 20
Identification 20
Instrument displays 20
Localiser operation 21
Coverage 21
Glidepath 22
Coverage 22
Marker beacons 22
ILS tracking 23
Back course approaches 23
ILS Categories 23
Calculations 24
System monitoring 24
2
,Microwave landing system 24
The horizontal transmitter (azimuth) 25
The elevation transmitter 25
MLS aircraft equipment 25
Primary and secondary radar 25
Moving target indication (MTI) 27
En-route surveillance radar 27
Terminal surveillance radar 27
Approach surveillance radar 28
Airborne weather radar 28
Predictive wind shear (PWS) 29
Scanner Tilt Settings 29
Multi-scan radars 30
Mapping radar 30
Distance Measuring Equipment (DME) 30
DME Range and DME Derived Groundspeed 32
DME with ILS 32
Secondary surveillance radar (SSR) 33
Modes A and C transponder 33
Special codes 34
Mode S all-call 35
Satellite navigation systems 35
Navstar GPS 35
GLONASS 38
GALILEO 39
ABAS – Airborne Based Augmentation Systems 40
AAIM 40
Ground Based Augmentation Systems (GBAS) 41
Satellite Based Augmentation Systems (SBAS) 41
Navigational displays 42
FMS 43
Aircraft position 44
MCDU 44
Primary Flight Display (PFD) 44
Navigation display (ND) 45
Performance based navigation 45
Components of PBN 46
Linear and angular performance requirements 46
Continuity 46
Accuracy an integrity 46
Functionality 47
Required functions for PBN 48
Navigation specification levels 48
Developments in PBN 49
Airspace capacity 49
Components of PBN Routings 50
ARINC 424 51
RNP/RNAV Key Features 51
3
, General information
To produce radio waves, the following parts are necessary:
- Oscillating electrical current
- Aerial
Moving electrons in the aerial produce a changing magnetic field, moving away from the
aerial at the speed of light.
An aerial is a transductor: device that transforms energy from one type to another. In this
case: alternating current à free electromagnetic wave (RF – radio frequency).
Receiving a signal
When the changing electromagnetic waves pass a receiving aerial, the electrons in the
receiving aerial start to move in an identical way, compared to the transmitter.
- Frequency (Hz – Hertz). The number of complete cycles a wave makes during a
specific period of time. Usually measured in cycles per second.
- Speed of light = 3 x 10 m/s
8
The higher the frequency, the smaller the wavelength. In formula:
#
! = where λ is the wavelength (m), f is the frequency (Hz) and c is the speed of light
$
(m/s).
Wavelength is the physical distance travelled by a radio
wave during one cycle of transmission. It looks like:
Frequency spectrum
The frequency spectrum is based on the International Telecommunication Union (ITU)
classification.
A lot of questions on the official EASA exams are asked about the above table!
4
