DE102006024129B3 - Long /short band antenna for e.g. missile, has high frequency connection with outer insulation arranged below extension of preliminary body, where body migrates into narrow extension - Google Patents

Abstract

The antenna (1) has a high frequency connection with an outer insulation arranged below an extension of a preliminary body (2). The preliminary body is designed in wedge-shape. The opening angle of the preliminary body lies in the dimension of 30 degrees and the sweep angle lies in the dimension of 35 degrees. The body migrates into a narrow extension (20). The base plate has a chamfered form (40) in the front area.

Description

The The invention relates to an L-band or S-band antenna for re-entry bodies, in particular for in the atmosphere entering missiles the preamble of claim 1.

to Evaluation of a controlled reentry of a missile in the atmosphere is a continuous real-time data transmission and positioning from the missile required to a ground station. This is the focus in ensuring the data transfer through at the outside structure payload mounted missile antennas. While In the reentry flight, the exposed missile antennas are very exposed exposed to high thermal loads.

The antennas used to date for telemetry and GPS data transmission in the L or S band are predominantly designed as blade antennas and have been used in this form for years. (Please refer DE 102 20 440 , especially 4 ) The operational area essentially comprises sounding rockets and satellites.

at a stable re-entry of the missile in the height range of 90 to 20 km is a complete one Telemetry data transmission of the sensors and possibly of experiments as well as a position determination via GPS to ensure. On the telemetry side, the blade antennas are in the S band range (2.25 GHz). With a stable re-entering payload However, the antennas are exposed to very high thermal loads. Also by particle ionization and plasma formation can impairments during data transmission occur, especially in flight experiments in much higher speed ranges.

to data transfer be in real time for a Mission and others Four blade antennas are used, which, evenly distributed over the Circumference and to the longitudinal axis aligned with the exterior structure the payload are attached. The antenna radiation pattern thus shows a complete cover. While the reentry phase However, the antennas in any way mechanically and electrically change.

The Previously used S-band antenna consists of a high temperature resistant Copper beryllium alloy (CuCo2Be, Berylco 10) with a melting point at about 1030 ° C. The HF connection exists from an SMA socket whose inner conductor also made of copper-beryllium alloy consists. The inner conductor is, however, by a sheath made of Teflon protected and contacts the S-band antenna in the upper part.

at the missile antenna type used so far keeps up an uncontrolled re-entry into the earth's atmosphere the internal connection of the S-band antenna did not stand up to the high thermal loads, what et al also on the bad heat protection and the design of the aerial antenna is due. Further, this is also depends on the position and the position of the flying antenna relative to the flow.

by virtue of of thermal loads of the missile antennas, for example with salvaged antennas to a degradation of the antenna connection come to discoloration of the Alloy was to recognize, by which on special temperature loads and flow paths closed back could be. Furthermore, the inner conductor and the Teflon insulation were melted.

This indicates that high temperatures are punctual and short-term have occurred, because the lower part of the Teflon insulation is intact. From discoloration let himself go an oncoming flow derive at an angle of about 45 °, in which the inner conductor outside of the flow shadow of the antenna preform lies. (As long as the inner conductor is in the protection of the pre-body, he stays i.a. intact.) The melting of the upper part of the Teflon insulation released a temperature of about 300 ° C below 900 ° C shut down. The upper part of the antenna showed strong tarnish colors from black to violet ranged.

Of the preforms The antennas used so far generated under optimum flow conditions (Angle of attack α = 0 °) in his Caster a so-called Totwassergebiet, in which by reduction the Mach number higher Temperatures prevail. The general occurrence of this slipstream area let yourself by the structure of the antenna itself can not be avoided. In the previous ones Requirements and operating modes, however, was the 5-band flying antenna sufficient.

meanwhile however, will provide a safer telemetry and GPS transmission while re-entry into the atmosphere. For one such use is the missile antenna type used so far no longer suitable, since even with controlled reentry with up to 3 km / s or 10800 km / h and at the then occurring high temperatures the proper function of the antenna is no longer guaranteed is.

The object of the invention is therefore, the functionality in terms of securing the GPS and telemetry data transmission of antennas in the L or S band at extreme temperature load in the hypersonic range during a controlled Wieder entry of payload bodies.

These The object is achieved with the subject matter of claim 1. Advantageous developments are the subject of the claim 1 directly or indirectly referred back Claims.

at the L- or 5 antenna is the preform wedge-shaped in the way designed such that its opening angle α in the order of magnitude from about 30 ° as well whose sweep angle β is approximately in the order of magnitude from 35 ° to 40 °. Furthermore, the antenna goes in the rear area in a narrower extension over.

Of the In this way modified pre-body of the antenna is thus due to the widening and narrower extension at the end of the expansion area enlarged and simultaneously shifted forward, causing the direct expansion is attenuated at the radius of the antenna arm.

Nice at slightly oblique Anströmungsbedingungen at an angle of 1 to 10 degrees is in the previous antenna the antenna central area exposed to the free flow. The wedge-shaped according to the invention preforms with an opening angle α of 30 ° protects against the Head at flow angles of up to 15 °.

At the only bevelled Bottom plate of the previous antenna, a compression shock is generated, which lies fully in the antenna dialectic. There according to an advantageous development The bottom plate is executed rounded, this rounding leads to the bottom plate to a detached one Push at an oblique flow, whereby the shock waves are further away from the core area.

According to one Another advantageous embodiment of the invention is the bottom plate to the outer contour the payload, in particular a missile adapted in such a way that they are flat throughout on the outside structure is applied. Because of the opposite the previous antenna design considerably more massive interpretation of the preliminary body, the essential Part of the kinetic energy of the incoming particles receives is thus a much better heat dissipation to the bottom plate and thereby also the payload / missile outer structure reached.

to boot is according to the invention the sweep angle β of Leading edge of the preform in comparison to the previous embodiment of the preform of 45 ° reduced by about 35 °. There, as already stated the bearing surface the bottom plate better, as continuous flat, to the payload outer structure adapted and thus attached to this is also a better way heat dissipation to achieve.

in the With regard to the discussion about adjoining and detached Compression collisions at the previous antenna are all sharp edges of the previously used antenna performed rounded. Preferably In this case, the curves of the preform have small radii in the Magnitude of about 1.5 mm, while the curves on the bottom plate in the order of about 2.5 mm lie.

Various Measurements in the high-frequency range have the perfect electrical function the antenna according to the invention approved. simultaneously The measurements showed an adjustment of well over 20 dB Reflection attenuation at a bandwidth of 160 MHz.

Further Temperature measurements have shown that antennas designed according to the invention the heat energy much better delivered to the payload outer structure, which in turn leads to a lower slope in the temperature rise leads. In addition, a better protective effect of the Antennenvorkörpers was detected.

On Because of the modification of the bottom plate was also an oblique flow good thermal protection given. Furthermore, the measurements have shown that the time to reach the critical temperature in the SMR antenna connector through the antennas according to the invention extended by up to 15s has been. This in turn can be used at mission times at the re-entry of a missile be decisive from 30 to 60 seconds.

following becomes a preferred embodiment an S-band antenna described. Show it

1 a schematic sectional view of an S-band antenna along the line II in 2 ;

2 a schematic plan view of an S-band antenna, and

3 a perspective not to scale representation of an S-band antenna.

One in its entirety 1 designated S-band antenna has a substantially rectangular bottom plate 4 at their front, in 1 to 3 right end a rounding off 40 having. Further, at both ends of the bottom plate 4 lowered holes 42 educated.

With the bottom plate 40 forms a hook-shaped preform 2 one unity. Like the sectional view of the 1 it can be seen, closes the preform 2 the S-band antenna 1 with the bottom plate 4 one Sweep angle β of 35 °. This sweep angle β is preferably about 40 ° in the case of an L-band antenna not shown in the figures. In both the S-band and the L-band antenna, the so-called opening angle α is preferably about 30 °.

Like the top view in 2 and the perspective view in 3 can be seen, is the preform 2 in a considerably narrower extension 20 above. Below the extension 20 in the "slipstream" of the precursor 2 is an RF connection to the antenna provided, of which except the mounting holes in 2 and 3 only the sheath 3 can be seen, which preferably consists of a special ceramic, such as oxide ceramics.

In the perspective view in 3 are the edge roundings 21 both on the preform 2 and its extension 20 can be seen, each having a small radius, preferably in the order of about 1.5 to 2 mm. Furthermore, the edges are rounded off 41 on the long sides and the front rounding off 40 the bottom plate 3 played. The radii of the edge roundings 41 at the bottom plate 4 have slightly larger radii and are on the order of about 2.5 mm.

1

S-band antenna

2

preforms

20

Extension of 2

21

Edge rounding of 2 and 20

3

jacket an RF antenna

4

baseplate

40

front rounding on 4

41

Cantering on 4

42

lowered drilling

α

opening angle

β

sweep angle

Claims (7)

L- or S-band antenna for reentry body, in particular for reentry into the atmosphere missile consisting of a bottom plate, a wedge-shaped preform and an arranged under an extension of the preform RF terminal with external insulation, characterized in that the preform ( 2 ) is wedge-shaped in the way that its opening angle α in the order of 30 ° and the sweep angle β is in the order of 35 ° and in the rear region in a narrower extension ( 20 ), and that the bottom plate ( 4 ) in the front area a rounded shape ( 40 ) having. L or S band antenna according to claim 1, characterized in that the bottom plate ( 4 ) is adapted to the payload / missile outer structure. L or S band antenna according to claim 2, characterized in that the bottom plate ( 4 ) lies flat on the underside of the payload / missile outer structure. L-band or S-band antenna according to one or more of the preceding claims, characterized in that, in order to reduce temperature peaks with controlled flow, the preform ( 2 ) and its extension ( 20 ) and the bottom plate rounded edges ( 21 ; 41 ) exhibit. L or S band antenna according to claim 4, characterized in that the edge fillets ( 21 ) of the precursor Klei ne radii in the order of about 1.5 mm and the edge rounding of the bottom plate ( 4 ) are on the order of about 2.5 mm. L- or S-band antenna according to claim 1, characterized in that for the thermal insulation of the terminal contacts of the RF antenna, this a sheath ( 3 ) of temperature-resistant ceramic. L or S band antenna according to claim 6, characterized in that the temperature resistant ceramic sheath ( 3 ) consists of glass-ceramic.