Ku-Band OMUX 500 Watt per Channel

  • Status
    Ongoing
  • Status date
    2011-01-26
Objectives

To offer HDTV (High Definition Television) services with small diameter receive antennas (<0.5m), higher levels of EIPR (Equivalent Isotropic Radiated Power) of the satellite transmit antenna are required. For that purpose, transponders with an output power in the range of 500W per channel are needed to feed the antenna network.

The objective of this project is to develop, design, realize and test a multichannel OMUX with high unloaded Q-factor, suitable for an input power in the range of at least 500W per channel.

To achieve this task, different high power filter concepts will be assessed and analyzed. Special attention will be payed to the most critical aspects of high power OMUX design like heat dissipation and the occurrence of multipactor and corona breakdown. The selected approach will be substantiated by dedicated FEM simulations with respect to these risks.

After the selection of an appropriate filter concept and the development of a suitable manifold, a 3-channel Ku-band OMUX demonstrator with an input power of 500W per channel will be designed, manufactured and evaluated. Furthermore a feasibility and concept study for an 8-channel 500W per channel OMUX will be elaborated.

Challenges

The following key issues are addressed by the “Ku-band OMUX 500 Watt per Channel” project:

As a demonstrator, a multi-channel OMUX with high unloaded Q-factor, suitable for an input power of at least 500W per channel shall be developed and realized. To achieve this task, different high power filter concepts will be assessed and analyzed.

Special attention will be payed to the most critical aspects of a high power OMUX design like heat dissipation and the occurrence of multipactor and corona breakdown. This will be done with the help of a dedicated software tool, upgraded in the frame of this project and by dedicated physical analysis.

After the selection of the appropriate filter and manifold concept, a 3-channel Ku-band OMUX demonstrator with 500W per channel will be manufactured and tested. Furthermore a feasibility and concept study for an 8-channel 500W per channel OMUX will be elaborated, based on the insights gained during the development and test of the 3-channel OMUX.

Benefits

To offer HDTV (High Definition Television) services with small diameter receive antennas (typically <0.5m), higher levels of EIPR (Equivalent Isotropic Radiated Power) of the satellite transmit antenna are required to feed the antenna network. For that purpose, transponders with an output power in the range of 500W per channel are needed.

As a part of the transmit path, OMUXes sustaining input powers as high as 500W per channel are required in order to handle these power levels and thereby allow for the reduction of the receive antenna diameter.

Features

Based on the selection of the optimal waveguide concept (see above), a 3-channel Ku-band OMUX for an input power of 500W per channel will be developed and realized. Attention will be paid not only to the insertion loss, bandwidth and power handling capability but also to thermal losses, frequency stability, mass, volume and various other design aspects.

Critical aspects of the high power OMUX design – like the potential occurrence of multipactor and corona discharge – will be examined by additional FEM simulations and testing.

The 3-channel, 500W per channel Ku-band OMUX will be subjected to various electrical, mechanical and thermal analysis – among those also multipactor and RF breakdown analysis at ambient conditions.

Based on the insights gained during the realization and testing of the 3-channel OMUX, a feasibility study for an 8-channel OMUX with 500W per channel will be performed to complete this project.

Plan

The project consists of three phases:

In phase one, high power filter realizations and temperature compensation techniques are reviewed. Three high-power filter design concepts are compared in detail.

In phase two, one or more high power filter and compensation concepts are chosen and designed, manufactured, tuned and tested. This comprises also the simulation and analysis of multipactor and RF breakdown.

In phase three, a manifold concept will be chosen and analyzed. Based on the selected filter and manifold concept, a 3-channel OMUX demonstrator will be manufactured and tested. Furthermore a feasibility study for a 500W 8-channel OMUX will be undertaken.

Current status

Phase one of the project, the “High Power Filter Review and Trade-Off” has been completed. Based on a detailed filter concept trade-off and breadboard testing, the presumably optimum solution with respect to power handling capability, insertion loss, bandwidth, thermal losses, frequency stability, mass, volume etc. has been identified.

Project phase two “Development, Manufacturing and Test of Chosen High Power Filter” is currently in progress. The High Power Filter has been designed, the corresponding Filter CDR has taken place and EM manufacturing was started. After completion of the manufacturing and tuning process the High Power Filter will undergone a tough Low- and High- Power test program which results will be reviewed during the subsequent Phase 2 Close-Out Meeting.

In parallel to these activities a software tool is being enhanced to allow the FEM simulation of the filter, combiner and OMUX with respects to analysis of Multipactor and RF breakdown.