Electric beacon

A beacon (english radio beacon station) is to enable a radio station of the radionavigation service, whose releases are destined to a mobile radio station to establish their bearing or direction in relation to the beacon as defined in the Radio Regulations Radio Regulations ( Radio Regulations ) of the International Telecommunication Union.

• 3.1 With non-directional beacons ( NDB ) 3.1.1 DF method
• 3.1.2 hyperbolic

Classification

Basically beacon leave in undirected Beacon, divide -looking beacon and VOR. The directional beacons include localizer ( localizer ) and glide path ( glideslope ) to the rotary beacons include civilian use VHF omnidirectional radio range (VOR) and the military tactical air navigation ( TACAN ).

Radio navigation method

With non-directional radio beacons

A non-directional beacon ( NDB ) is a ( long wave ) transmitter, which radiates equally well in all directions, a continuous signal. Its original mission was to enable a pilot to Richtungpeilung airfields, so the transmitter is modulated to identify with one ( Morse ) code. The direction to the NDB, which is marked on maps as a point, can be determined with rotating directional antennas. In general we can distinguish two navigation methods:

DF method

In the DF method, the receiver can determine the direction of origin of the signal relative to the receiver by means of a rotatable directional antenna or by a plurality of fixed directional antennas. Knowing the directions of two beacons, one can derive from its position ( cross-bearing ).

Hyperbolic

In the hyperbolic send at least three beacon almost simultaneously each time signals that arrive slightly offset at the receiver. From the difference in the signal propagation times, the receiver may change its position relative to the transmitting stations detect ( " My distance from transmitter A is x kilometers bigger than my distance from transmitter B"). Since the position of the transmitting stations is known, can be derived from the current position. Hyperbolic therefore not based on the determination of direction, but the distance determination. As result from the signals of only two transmitting stations several possibilities for the calculated position, lying on a hyperbola (hence the term hyperbolic ), you need at least three stations.

With directional radio beacons

Looking beacon Send preference in a certain direction, for example in the entry lane of an airport. In order to build according to precise directional antennas, they must send with very short wavelengths in the VHF range. They are used when a vehicle is to follow the radiated from the directional antenna of the beacon transmitter.

With rotating beacons

Omnidirectional radio broadcast in every direction another signal and are therefore marked on maps with a compass rose. The evaluation of their signals to indicate to the navigator, in what direction relative to the beacon it is located. The direction is designated by the term radial.

For the determination using a transmitter, which also has a full radiator next to a rotating narrow main lobe. The transmitter is sending after each passage of a certain zero point of the rotary lobe an audible tone or otherwise measurable signal on the omnidirectional antenna. The evaluating electronics in the plane determines from the known orbital period of the fire as well as the time interval between the arrival of the main lobe at the measurement receiver in the aircraft and the acoustic tone, the relative angle to the beacon.

For your own location, you can use another beacon for the production of a cross bearing.

Radio navigation systems

With non-directional beacons ( NDB )

DF method

• Radio compass (ADF )
• Radio fire

Hyperbolic

• GEE
• LORAN
• Shoran
• Tropic
• Chaika ( Radio Navigation )
• Decca navigation system
• Alpha
• Omega navigation method

With directional radio beacons

• Early Lorenz-A/N-System
• Lawrence ultra-short landing beacon
• Knickebein ( beacon )
• Instrument landing system (ILS )
• PRMG

With omnidirectional radio range (VOR )

• Telefunken compass transmitter
• Further developed Lorenz-A/N-System
• Sun and Consol
• TACAN
• RSBN

While in maritime navigation, radio beacons have been replaced by more modern satellite navigation process and come only in remote areas of application, they are in aviation as part of the IFR (Instrumental Flight Rules IFR ) is still used extensively.

However, many Seefunkfeuer were not shut down, but rebuilt in DGPS beacon (differential GPS). DGPS beacon can be easily distinguished from other beacons: DGPS beacon give only a noise in the loudspeaker again, whereas conventional beacons send their identifier permanently as Morse code.

There are also radio beacon that. Besides their identification in addition spoken weather reports for the lake or transmitted aviation, by the method of amplitude modulation or the compatible single-sideband

Flight Beacon

Flight beacon for route navigation may be basically divided into:

• Non-directional beacon ( NDB - Non -Directional Beacon ) is located by the ADF ( "Radio Compass " )
• Directional beacon (eg VOR - Very high frequency omnidirectional radio range, TACAN )

By suitably precise time measurements a statement about the distance to the airport beacon is possible with some aeronautical radio navigation method. This is realized by a DME ( Distance Measuring Equipment), which is built next to the VOR. In connection with the course information of the VOR flight beacon position determination is thus possible at any time.

The price information is based on the phase shift between a radiated in all directions, and the signal received on the radio line of position related signal is evaluated. Fly the aircraft, for example, with a westerly course (270 ° ) on the VOR to ( " inbound " ) or with an easterly course ( 090 ° ) away from ( "outbound "), then the phase difference between the directed and undirected the signal 90 degrees. In the approach to the beacon with East Course (inbound, 090 ° ) and departure from this course with the West (Outbound, 270 °), the phase difference is 270 °.

For better understanding, the following conceptual model: A lighthouse shines every six minutes a short light signal equally in all directions. At the same time each starts a horizontal circumferential, tightly bundled beam of light exactly 6 minutes = 360 seconds required for a full orbit = 360 degree, ie one degree per second. A skipper who, after the flash of light on the lighthouse top looks the Peilstrahl 135 seconds, knows that he is 135 ° is on the course line.

A VOR / DME station is additionally equipped with a DME unit ( Distance Measuring Equipment ).

In the military flight operations is (still) the Tactical Air Navigation ( TACAN ) for the application that is based on a principle similar to VOR, but by a factor of 1.2 to 2 is more precise. Located VOR and TACAN ground stations at the same position, the combination is also known as VORTAC.

VOR / DME are still by the law of the instrument navigation primary sensors. However, the process is more and more replaced by GPS.

Seefunkfeuer

A Seefunkfeuer is an imaginary mostly for maritime use Beacon, which is mainly operated in chains, all Seefunkfeuer broadcasting different Morse IDs in this chain in the course of a cycle time. As with NDBs the modulation type A2 is mostly ( sounding telegraphy ) applied.

The transmit antennas and transmission powers of Seefunkfeuern correspond to those of distance beacons. In addition, there are in some countries Seefunkfeuer that transmit weather reports in AM or SSB. With the increasing spread of the GPS Seefunkfeuer in Germany were shut down on 1 January 2000.

The stations were partly rebuilt in DGPS stations or NDBs.