APPENDIX B. EUROPEAN SITE REPORTS

Site: AEG Elektronische Röhren GmbH (AERG)
Söflingerstrasse 100
D-89077 Ulm Germany

Date Visited: September 10, 1997

WTEC: C. Mahle (report author), W. Brandon

Hosts:

BACKGROUND

The ownership of AERG has changed in the last two years. AEG Elektronische Röhren GmbH is now a company of Thomson Tubes Electroniques, Vélizy, France. Thomson's TDH (Thomson Department Hyperfrequences) Division, which is also in the traveling wave tube (TWT) business, is under the same ownership, and work at Ulm and Vélizy is now to some degree coordinated. The company plans to continue manufacturing space TWTs at both locations, even if the product line has similar or identical products. For instance, if a comparable TWT is available from both sources, the customer may decide which TWT to purchase. This leaves essentially three space TWT manufacturers worldwide (Hughes EDD, Thomson and NEC).

MARKET

The worldwide market in space tubes was approximately $140 million in 1996. The satellite manufacturers and in particular payload manufacturers are not just located in the United States, but are now distributed worldwide, and include Russia. There are several ways in which the TWT and the electronic power conditioner (EPC) can be integrated to form a traveling wave tube amplifier (TWTA). Today the TWTAs are often integrated by the TWT manufacturer (NEC or Hughes EDD); frequently the payload manufacturer procures the TWTs and integrates them with its own EPC (Hughes, Lockheed Martin). AERG now has the capability to build EPCs and integrate the TWTAs if the customer so desires, however, AERG will concentrate on TWTs as its main product.

AERG has excellent cooperation with many of the spacecraft and payload manufacturers; for instance, some firms let AERG perform all necessary R&QA activities without supervision. AERG considers their customer relationships as a major selling point.

AERG was producing about 60 space TWTs per month at the time of this visit.

R & D ACTIVITIES

AERG representatives presented a graph showing the improvement of TWT efficiency over time including projections up to the year 2004 (Figure B.1.).


Fig. B.1. TWT efficiency.

A large part of the improvements over the last few years is due to very sophisticated software modeling and optimization computer programs. TWT efficiency and performance is expected to improve gradually; no major breakthroughs in technology are expected. For instance, diamond helix supports will bring a small improvement in efficiency. Adding another collector (the current production models use 4 collectors) is likely to increase the efficiency by another 2% while the EPC changes to accommodate a fifth collector are minimal.

The current status and forecast for AERG space TWTs is listed below:

Frequency band

Current Laboratory

Current Laboratory

L-band
Rf output (W)
Efficiency (%)

52

60

C-band
Rf output (W)

60

120

Efficiency (%)

60

67

Ku-band
Rf output (W)

140

220

Efficiency (%)

72

75

Ka-band
Rf output (W)

75

100

Efficiency (%)

63

72

The efficiency of an S-band TWT would fall between L-band and C-band.

AERG representatives feel that a 60 GHz TWT (25 to 30 W with helix and up to 100 W with interdigital slow wave structure) can be put into production within 12 months when the requirement for such a tube becomes apparent.

AERG has some design activity at 94 GHz; its engineers feel that a space TWT at any frequency between 30 GHz and 94 GHz can be designed and produced within one year after requirements definition.

AERG builds also TWTs for ground applications. Asked if a TWT at 30 GHz with a 2 to 4 W power might be cost competitive with an SSPA, WTEC's hosts stated that, in their opinion, the SSPA would eventually be cheaper, certainly below the 10 W level.

CONCLUSIONS

AERG is a very competent TWT manufacturer with excellent R&D and production facilities and will continue to be very competitive in the worldwide market.


Published: December 1998; WTEC Hyper-Librarian