DE1932295A1 - Method for providing a signal identifying the main sector of a sector directional radio beacon - Google Patents

Description

• .- .. STANDARD ELEKTRIK LORENZ AG

Stuttgart-Zuffenhausen
. Hellmuth-Hirth-Str. 42

K.D. Eckert - H.J. Röper 4-1

"Method 2 for the provision of a signal that characterizes the main sector of a sector directional radio beacon"

The invention relates to a method for emitting a uniqueness signal in the case of a directional radio beacon, which identifies a sector of a certain latitude, for example IB , around the approach baseline (AGL), in which azimuth information for plug-in vehicles cooperating with this radio beacon is broadcast ¹ are equipped with the TACAN receivers intended for route navigation.

Such a directional radio beacon and the different generation of the same radiation field in the specific sector compared to the TACAN system, as provided by the TACAN system all around over 30 °, is in the older proposals (P 15 91 610.6j P 15 91 611.7; P 16 16 532.5) has been described. In the simplest version on which the invention is based, for a sector of - lo ° of three at a distance of 5 · λ / χ (Χ = operating wavelength) or 9'5'X / K ^{from the} first antenna an unmodulated carrier (range 10000 Hz) or the ο, ine modulation sideband of the carrier with a first modulation frequency (e.g. 15 Hz, i.e. 1000 MHz + 15 Hz) or the qine sideband of the carrier with one to the first harmonically related second modulation

. frequency (e.g. 135 Hz, i.e. 1000 MHz + 135 Hz).; · The high-frequency waves are transmitted as a pulse pair sequence with

. Correct spacing of the individual pulses (12 us) as with the TACAN- ■ System broadcast; * '

Ktz / Gr
3,6.69

, 00088 2/107 9 ,

K.D. Bokert - H.J. Röper 4-1

This type of generation of the point field in the navigation method described in the older proposals (SETAC) due to the large antenna base of. approx. 15 wavelengths and the associated splitting of the radiation diagram ambiguities in the azimuth measurement. The sector relevant to the azimuth display has an opening angle of - lö ° on both sides of the Center perpendiculars on the connecting line of the antennas. So that the user of this point fire only uses this main sector for the azimuth measurement, this should be special P must be marked.

Various ways of labeling are conceivable and obvious.

If the antennas used for sector beacons are directional radiators that only generate strong radiation within the main sector, one could think of the Marking to emit special signals from an additional antenna of the azimuth antenna system; the kind the broadcast could for example take place in the manner that the information content of the azimuth signals outside the Main sector (uniqueness sector) destroyed or ineffective

* will.

The same goal can be achieved in that an omnidirectional antenna is used to broadcast the carrier and antennas bundling only to broadcast the sidebands, such as ¹ in one of the older proposals (P 16 16 532.5) for the purpose of an all-round distance measurement. As a result of the greatly reduced sideband radiation outside the uniqueness sector, the carrier predominates there, and the amplitude modulation carrying the information disappears. ■ almost; an azimuth measurement is therefore not well possible ^{outside of the uniqueness sector x.}

099882/107 *

K.D. Eckert - H.J. Röper 4-1

One could also think of the identification signal by generating a directional signal for the sector to provide additional all-round information. This information could be provided by someone at the same location TACAN-Minibake will be broadcast. The disadvantage and inconvenience of such a solution are obvious: Increased effort on the ground and εη board the aircraft, whereby in particular, the necessary on-board interventions in the receiving equipment are to be rejected because the reception of the Sector azimuth information that normal TACAN on-board devices should be used for (compatibility).

The invention thus relates to a method for providing the main sector of a sector directional radio beacon characterizing signal, in which directional radio beacon for azimuth determination the rotating radiation field of a by a pulse pair sequence with a certain distance (e.g. 12 ^ s) of the individual pulses of a pulse pair sampled, sinusoidally amplitude-modulated high-frequency wave by means of an am At the end of the runway built-up antenna system is generated and at the receiving side in on-board stations by phase comparison a reference signal transmitted by the antenna system with the direction signal obtained from the amplitude modulation of the azimuth of the on-board stations in this is determined.

According to the invention, by means of a second antenna system built next to the runway and at right angles to the touchdown point provided for landing aircraft, a third pulse following each pulse pair at a certain distance (A t, eg 36 p) is transmitted on the same carrier wave; the distance between the third pulse and the first of the individual pulses of the pulse pair is measured and displayed in the aircraft.

009882/1079

K.D. Eckert - H.J. Röper 4-1

The invention is explained in more detail with reference to figures in the figures represent schematically;

1 shows the runway with antenna systems A and E and the sector shown;

2 shows the transmitting device assigned to the azimuth antenna system A;

Pig. 5 assigned to the elevation antenna system E. Receiving-transmitting device;

4 shows that associated with the azimuth antenna system A in a second exemplary embodiment Distance measuring device;

5 shows the on-board receiving device for determining the distance between the third pulse and the first Pulse of the pulse pair;

6 shows the lateral assignment of the individual pulses.

The method described thus allows labeling of the uniqueness sector, independent of, the charisma and Propagation conditions. The invention is based on the assumption from the older proposals that an azimuth measurement (SETAC-A) and an elevation measurement (SETAC-E) in one specific sector. ·

The transmitting device of Fig. 2 with the devices share 21 (signal generation) and 22 (transmitter for carriers and sidebands) is known and does not belong to the scope of the invention.

• A 009882/1079

K.D. Eckert - H.J. Röper 4-1

The method of elevation measurement is improved according to another pre-sole in that the antenna system E (Fig. 1) for transmitting the elevation signals (SETAC-E) to the side of the runway at a certain distance from it at the level of the intended touchdown point T (Pig. I) is installed for landing aircraft, while the antenna system A is set up for broadcasting the azimuth signals at one end of the runway. The elevation signal is a pulse (pulse 3, FIG. 6), which follows each random pulse pair serving for azimuth measurement (pulse 1 and 2, FIG. 6; distance 12 ps at a fixed distance At (e.g. 36 jis; FIG. 6) According to the other proposal, the third pulse (pulse 3) representing the elevation signal is generated in the transmitting device (34, 35J Fig. 3) assigned to the antenna system E in that the pulse pairs emitted by the azimuth antenna system A are generated in one of the transmitting devices (34 , 35; Fig. 3) of the elevation antenna system E associated receiving station (Fig. 3) are received (30, 31) and decoded (32); with the help of a pilot pulse device, as it is known from precision distance measurement ensured that the third pulse is always that precisely defined time later (delay 33, Fig. 3) * e.g. 36 ^ s after receiving the first single pulse (or 24 ^ s after receiving the second single pulse) of a pulse pair transmitted by the azimuth antenna system A. in the elevation Antenna system E assigned receiving station (30, 31, 32, 33) from the elevation antenna system E is transmitted. I -

■ ■ ■ ■ '"·' ■■■ '!" - ■ ""

The individual parts of the device of FIG. 3 are known, and the summary of the parts of the device to form arrangements that one Fulfilling the desired function is the task at hand

familiar to the person skilled in the art .; . ,. - - - - ■ - """* · ■ - ['.. *""--" ■ "'. * -.

/ The same applies to tu6l ¥ -for the equipment compilations according to Figures 4 and 3 ^, which are to be mentioned later.

K.D. Eckert - H.J. Röper 4-1

On the connecting straight line AE between the azimuth and elevation antenna systems, this time interval between the third pulse and one of the individual pulses of the pulse pair is always retained for an aircraft working together with the radio beacon. However, if the aircraft deviates from this straight line AE on approach, the time interval between the third pulse and the pulse pair changes by a value t InAt + t (? Fig. 6) during reception due to the different transit times of the waves from the two antenna systems to the aircraft .

The idea of the invention is based on this consideration. By Determining the time interval At + tr of the third pulse from the first single pulse of a pulse pair can therefore be done with a corresponding receiver (50, 51 * 52, 53 * 5 ^ 1 Fig. 5) equipped aircraft a criterion (decoder 52, uniqueness control 52, display 5 ^) for the approach of the radio beacon in the main sector. The azimuth is determined using of the device parts 55 (decoder for pulse 1/2), 56 (azimuth evaluation) and 57 (azimuth display).

If one leaves a certain time for the value X. Variation to, is therefore a certain) range given by the maximum permissible value ν, in which the pulses received on board are still decoded as correct, then an area is defined by this range in the horizontal plane, which is surrounded by a hyperbola (H. , Fig. 1) is included, within the time 3 between the first pulse of the pulse pair and the third pulse At + τ. :

■.

The time at

A unö E.

is determined by two factors, namely by

and; V $ 8j distance AE outer form antenna systems

00tf iijt # _: i & *

the one on the side! ι Deviation of the measuring aircraft from the j Connected Afc of the two antenna systems, i.e. from Azimuth angle,

K.D. Eckert - H.J. Röper 4-1

In Fig. 1, the runway L with the azimuth and elevation antenna systems A and E, the approach baseline B, the intended, most favorable touchdown point T and the zone delimited by the hyperbola H, which coincides with the boundaries of the j56 ° sector coincides. It is to notice that the real conditions cannot be reproduced exactly in the drawing because the runway L with a length of approx. 3 km about 100 times as cross What should be drawn is how the distance between the elevation antenna system E and the approach baseline B. The runway L is therefore drawn interrupted in order to better represent the unambiguous zone - according to the real conditions to be able to. With these distances it is also clear that the straight line AE connecting the antenna systems A and E, around which the Hyperbolic field "as is known, with the approach baseline B approximately coincides. It is therefore permissible in the graphic representation to indicate the axis of the Hyperbola that defines the uniqueness zone as having the approach baseline B coinciding.

It can initially be assumed that the distance AE between the two antenna systems, if it is not the same for all point lights, is known for each point light of this type on board, and that the permissible deviation from the connecting straight line AE, i.e. the value τ, is given. Then, with the aid of an appropriately dimensioned decoder 52 (Fig. 5) for the pulse intervals and the uniqueness control 53 & n board, it can be determined whether the plug-in item is within the area defined by the maximum value of T and enclosed by the corresponding hyperbola E or not . If the maximum permissible value is now chosen so that the hyperbola - or rather its asymptotes - with the boundaries of the uniqueness sector, which is determined by the sector beacon from antenna system A for the azimuth determination 009882/1079

K.D. Eckert - H.J. Röper 4-1

coincide, then it is determined by the signal output by the decoder 52 (uniqueness control 53) whether the measuring plug-in item is located within the uniqueness sector or not. In this way the uniqueness area (display 5 ² O is determined.

It should be noted that in and of itself it is irrelevant for the functioning of the procedure whether the one in front Elevation antenna system E third pulse to be transmitted from the first or second single pulse from the azimuth ^ antenna system A transmitted pulse pairs is derived. It is only necessary to set the delay time (53> Fig. 3) to .select accordingly in order to activate the third pulse at the same time to set the desired position on the time axis. Since in the TACAN system the time interval between the pulse pairs is at least 60 με - 10 ^ s, is for the position of the third impulse given a wide margin; the time of occurrence of the third pulse is just like that to choose that it is at a sufficient distance from the second single pulse of a first pulse pair and from the first single pulse of the next pulse pair falls into this so-called dead time.

However, it is advisable to derive the third pulse to be transmitted by the elevation antenna system generally from the second individual pulse of a pulse pair, as the following exemplary embodiment shows.

However, if on board the plug stuff the distance between the two Antenna systems A and E (Fig. 1) is not known, or if you want to achieve that the system described in runways of different lengths even without the inclusion of the distance AE between the two antenna systems on board in the works in the same way, this can only be achieved through measures on the sending side. Provided one

\ 009882/107 9 · / ·

. , BAD O $! QINAt.

K.D. Eckert - H.J. Röper 4-1

The system can be designed as follows, regardless of the distance between the antenna systems: the time of transmission of the third pulse from the elevation antenna system E is derived from the reception of the second individual pulse of the pulse pair transmitted by the azimuth antenna system A. For this purpose, the distance between the individual pulses of the pulse pair emitted by the azimuth antenna system A (pulse 1 and 2, Pig. 6) is varied according to the respective distance between the two antenna systems. This is achieved in that by means of a known precision distance measuring device (Fig. 4) assigned to the Äzimuth antenna system A, the exact distance of the two antenna systems is measured in the interrogation process and with the result (control signal a; Fig. 4, Fig. 1) the The distance between the individual pulses of the pulse pairs is varied in such a way that, when measuring in the aircraft, the time variation vont, i.e. the distance between the first individual pulse of a pulse pair and the third pulse, i.e. Δ t + r, regardless of the distance between the two antenna systems A and E, always at the same azimuth angle remains constant. It is sufficient to carry out this distance measurement and the setting of the time interval between the individual pulses of the pulse pairs to be transmitted once and for all at each airport. If the distance between the two antenna systems at the various airfields varies between 2000 m and ^ 000 m, the necessary change in the interval between the individual pulses of a pulse pair, which is normally 12 ps, remains within the limits prescribed for the TACAN system.

The broadcasts of the azimuth and elevation antenna systems A and E are shared on board the aircraft Receivers (30, 51; Fig. 5) received in two channels (Azimuth evaluation, 55, 561 uniqueness check, 52, 53)

009882/1079 ° ^{/ o}

KD Eckert -, HJ Röper 4-1.

evaluated in a manner known per se and with appropriate Display devices (57 or 54). The uniqueness indicator (54) shows whether the distance t + τ of the third, from the elevation antenna system E transmitted pulse from the first single pulse of a pulse pair, the front azimuth antenna system A has been sent out, lies within the specified limits, i.e. whether the plug stuff is is located within the zone given by the hyperbola H (Pig. I).

% Claims 2 sheets of drawings «6 Pig.

009882/1079

Claims (2)

K.D. Eckert - H.J. Röper 4-1 Claims Method for providing a signal identifying the main sector of a sector radio beacon, in which-. 'Directional radio beacon for azimuth determination the rotating radiation field of a sinusoidal air.plit.uden-modulated high-frequency wave sampled by a pulse pair sequence with a certain spacing (e.g. 12 ^ s) of the individual pulses of a pulse pair is generated by means of an antenna system set up at the end of the runway and at the receiving end in on-board stations Phase comparison of a reference signal transmitted by the antenna system with the directional signal obtained from the amplitude modulation of the azimuth of the on-board stations is determined therein, characterized in that by means of a second antenna system (E, Fig. 1 ) each pair of pulses at certain: ". Distances (At, eg Jb ps; delay J> 3 * Fig. J>) the following third pulse is emitted on the same carrier wave that the pulse-shaped emanations, both the azimuth and the Elevation antenna system (A or E, Fig. 1) in a common on-board receiver (Fig. 5) are received, and that the distance of the third pulse (Zk t + τ ) from the first of the individual pulses of the pulse pair is measured (52, 53) and displayed (5 * 0) as an uniqueness signal. 2. The method according to claim 1, characterized in that; 3 the third "pulse to be transmitted by the elevation antenna system (E) is derived from the first individual pulse of the pulse pair transmitted by the azimuth antenna system (A) by in an 009882/107 9 K.D. Eckert - H.J. Röper 4-1 In a known manner, the pulse pairs are received (30, 31) and decoded (32) in a receiving device (FIG. 3) assigned to the elevation antenna system (E), and that after a corresponding delay (33) the pulse thus processed is sent to the modulator (3 ² O of the transmitter (35) is entered and broadcast (E). 3 · The method according to claim 2, characterized in that the to be sent out from the third elevation system (E) is derived from the pulse w zv / nits single pulse of light emitted from the azimuth antenna system (A) pulse pair. Method according to Claim 3 *, characterized in that the distance of the elevation antenna system (E) from the azimuth antenna system (A) is determined in a distance measuring device (Pig. 4) assigned to the azimuth antenna system (A) using the interrogation method and with the measurement result (control signal a, Fig. 4 and Fig. 1) the distance between the individual pulses of the transmitted pulse pairs (pulse 1/2, Fig. 6) is varied in such a way that upon reception on board the temporal variation of the distance between the third pulse and the first individual pulse of a pulse pair, is always constant at the same azimuth angle regardless of the distance between the two antenna systems (A and E, Fig. 1). 009882/1079 L e r s e i t e