Low Loss, High Power Dielectric Filters

  • Status
    Ongoing
  • Status date
    2008-11-14
Objectives

The objective is to demonstrate the low loss, mass and volume reduction for a high power filter at Ku Band using advanced dielectric material, considering all the high power issues associated with self-heating, multipaction, corona breakdown and PIM.

Development of a dielectrically loaded filter for use as a Ku Band High power channel filter will require a combination of proper materials selection and innovative cavity design. Recent advance in dielectric material with excellent microwave characteristics offers the potential of developing Ku dielectric OMUX. Paramount to success is the ability to limit heating and dissipate heat within the resonator assembly.

Challenges

Key issues are:

  • Availability of high performance dielectric materials for implementation,
  • Mechanical and thermal design of the dielectric loaded resonator filter,
  • RF/mechanical/thermal performance optimisation.
Benefits

With the anticipated growth of satellite communications systems and the ever-increasing demands of capacity, system architectures are increasing requiring large numbers of channel filters at ever increasing power levels. The implication to a provider such as Comdev is an emerging market for a technology that can deliver a low loss, low mass in a reduced volume Ku Band high power filter.

Traditionally the volume and mass of waveguide filters was dependent on the frequency of operation. Dielectric materials can be utilized to reduce size and mass significantly. In addition dielectric materials can often offer better pass band and out of band spurious performance then their waveguide predecessors.

Existing dielectrically loaded filters at C-Band and Ku-Band Input multiplexers demonstrate the mass and volume reductions. Based on market adoption of dielectric filters in the input multiplexer marketplace an offering of a similar technology to the output filter market would give COMDEV a significant new product and a further edge on our competitors.

Features

Several architectures are proposed from the onset of the project. All of the architectures and filter designs proposed have several key features in common.

  • Size: Dielectrically loaded filters can offer significant volume reductions over traditional guided wave filters,
  • Mass: Mass savings in concert with the volume reduction allow greater flexibility and capacity to multiplexer design,
  • RF performance: Properly designed and constructed, dielectric filters can offer substantively better out-of-band performance.
Plan

The proposed study work is separated into two phases with five work packages. The first phase covers dielectric high power Ku-band filter design, material and suppliers research and development. The second phase covers Breadboard manufacturing, test and design validation.

Current status

The project continues on plan and nears completion of formal testing. Significant test events such as mechanical and high power testing are complete. Hardware continues to meet or exceed expectation as the final stages of testing wrap up. Upcoming project events include completion of formal testing and preparation of final project reports. The project is on target for completion as planned.