TRAK Microwave

Loads And Terminations

IntroductionTRAK Microwave supplies an extensive range of waveguide and coaxial high reliability load and termination products for military, space and commercial applications. For over 20 years, TRAK’s termination products were exclusively usedin the design of TRAK’s ferrite isolators and passive microwave combiners. Today, TRAK specializes in unique solutions and full design services of load and terminations directly to customers. TRAK’s load and terminations offer optimizedperformance using only the most reliable design and assembly techniques available. These products are qualified to operate in the most rigorous environments including deep space probes, linear accelerators, strategic radarsand medical body scanners.

CapabilitiesTRAK has an extensive array of capabilities required to design and manufactureloads and terminations.

� 3-D Modeling/ Finite Element Analysis

� Static Stress

� Dynamic/Modal

� High Power RF Testing: High power sources are available from 1 to 18 GHz. Several examples are listed below:

� 950 to 2300 MHz, 150W CW

� 2900 to 3100 MHz, 700kW Peak, 700W average

� 8500 to 9600 MHz, 150kW Peak, 150W average

� 8000 to 18000 MHz, 400W average

� 8000 to 20000 MHz, 20W CW

� TVAC facilities test down to 1e-5 Torr (–55 to +125 C)

� EMC Radiated Emissions from 1 GHz to 30 GHz

� Water Testing

� Pressure to 20 Bar Gauge

� Water Chilling (+4 to +60 C)

Conduction Cooled Loadwith Thermal Switch, 10 W Avg.

Convection Cooled Load,200 KW Peak, 10 W Avg.

Convection Cooled Termination,20 W Avg.

TNC Load,90 W CW

Thin Film Load,90 W CW

Coaxial Load,10 W Avg.

Wedge Load,60 W CW

Space ApplicationsFor space applications, paramount importance is placed on the reliability of the components and sub-assemblies that together form the payload systems. This also is true for the high power RF systems where redundancy networks are notalways possible. TRAK high power terminations are used on high power RFsource or combiner networks, for example, SSPA output stages, TWTA and OMUX applications, where features such as mass and performance are equally necessary.

TRAK can provide an up-to-date program heritage list and operating parameters on awide range of load types and operating frequencies.

Military ApplicationsThe majority of the terminations supplied by TRAK into military systems are for radarapplications. Terminations are designed to handle fault, as in the load on an isolator,or planned incident power conditions, as in a dummy transmit load. The combinations of high incident power and typical military operating environmentsresult in designs that are required to operate reliably under extreme conditions forextended periods of time under worst-case conditions.

A wide range of cooling options are available including conduction, convection andwater-cooling features, which are designed based on system limitations and customerpreferences to ensure reliable operation.

TRAK’s proprietary thin film load technique is used extensively in military applicationswhere the lower mass and cooler operating temperatures are key benefits.

Commercial ApplicationsTRAK supplies terminations for civilian ATC, medical oncology and industrial processing. These markets require the same qualities in their products as the spaceand military markets and consequently, TRAK is well positioned to supply the types ofproduct required.

Coaxial Load,2 W Avg.

Coaxial Load,2 W Avg.

Convection Cooled Thin Film Load,60 W Avg.

Water Cooled Load,1000 W Avg.

Finned Load,150 W Avg.

WR340 Load100 W Avg.

WR75 Thin Film Load

Waveguide DesignWhen defining high power components, TRAK closely works withits customers to fully characterize the design parameters, while giving equal consideration to electrical performance, mechanicaland environmental constraints. Often compromises have to bemade. These are evaluated, weighted and reviewed with the customer to arrive at the optimal design solution.

Once operating parameters are established in concert with the customer’s design team and policies, TRAK executes the designsuch that each termination operates at the lowest possibletemperature within its physical and mounting limitations. To arrive at optimal solutions, TRAK makes extensive use of FEAand 3-D modeling tools to ensure mechanical and thermal integritywhile under transient and steady state loading conditions.

Waveguide TechnologyHigh Power terminations are produced using a number of complementary techniques and processes. Some of thesetechniques are standard to the industry, but several are proprietary to TRAK. Choice of technique is governed by customerspecification and physical size parameters. When possible, TRAK prefers it’s space qualified proprietary process that offers thedesigner a host of distinct advantages.

Wedge versus Thin FilmCarborundum wedge loads are used where the appropriate length of the termination precludes using thin film. Most lowpower loads are fabricated using wedges that are epoxied into place. Design of the wedge is dependent on thefrequency, operating power and desired electrical performance

TRAK’s proprietary low mass load technology has demonstrated its ability to operate under the harshest space and military envi-ronments. The technology allows combinations of high continuous power at elevated operating temperatures to function withthe utmost reliability, while also offering several added benefits. Where design constraints allow, waveguide terminations arefabricated adding minimal mass to the basic waveguide structure. TRAK uses a conformal RF load process to coat the internal waveguide structure. Successive coats are added to conform to the internal structure, thus building up a very thin layerof RF absorbent material. These coatings are then baked at very high temperatures to form a conformal load that is both lowmass and space qualified.

Thin film loads have key distinct advantages over wedge techniques:

� Mass - Approximately 50% lower then traditional wedge designs

� Epoxy Free - Increased reliability and reduced outgassing

� Precise Coating - Precise temperature gradient modeling

� Faster Thermal Time Constant – Temperature monitoring indicating absorbed power

� RF Probes – Easy intergartion for instantaneous signal monitoring

� Structures - Compact and complex fabricated shapes

Conduction, Convection and Liquid CooledWG Loads

Duplexer 100 KW Peak, 2 KW Avg.Water Cooled Load

Coaxial DesignTRAK uses proprietary and third party software to ensure that thethermal and mechanical designs are optimized and fully capable ofproviding operation under the most extreme circumstances. TRAKmakes extensive use of 3D mechanical modeling and finite element analysis to ensure optimum solutions. In addition, drawings can be accepted and interchanged with customers sothat the design process is robust and timely. To ensure best designpractices, a checklist of questions and guidance on the optionsand trade-offs is provided to all customers.

TRAK loads are all designed with safety and reliability in mind.Whether the application is intended to be in a satellite, militaryor medical enviornment, TRAK products will always meet or exceed your expectations.

Coaxial TechnologyTRAK has a broad line of coaxial packaged loads for space and military applications. These products are designed to meet EMC, RF, and mechanical requirements. TRAK designs these loads around commercially available proprietary chip terminations. The termina-tion is modeled within a suitable housing constructed to meet themounting, environmental and cooling requirements of the host system. The housings are generally made from High ConductivityOxygen Free Copper (HCOFC), which offers the most efficient transfer of heat from the chip to the cooling structure.Finished loads are nickel or silver-plated.

Other examples of coaxial loads can be seen in TRAK’s broad rangeof high power coaxial isolators. These loads are designed as partof the isolator housing, however the techniques may be readily integrated to offer compact robust stand-alone solutions forcoaxial terminations. TRAK has supplied approximately4000 high power terminations for space applications. A full heritage program list is available upon request.

Additional technical information is available from TRAK on load and termination designs and technology.

TRAK Microwave, an ISO 9001 & AS9100 registered company,designs and manufactures a diverse range of high reliability RF

and microwave integrated assemblies, subsystems, components and time & frequency systems for defense, space

and commercial applications worldwide. For more information on TRAK Microwave,

visit our web site at www.trak.com.

TRAK ia a unique solutions company while providing full design service for the supply of

high reliability products.

Forced Air Cooled Redundancy Switch andLoad, 10 KW Avg.

Duplexer 300 KW Peak, 6-5 KW Avg.Water Cooled Load, 2 KW Avg.

Duplexer 250 KW Peak, 4.5 KW Avg.Water Cooled Load, 500 W

コーンズ ドッドウェル株式会社 第二営業本部 デバイス営業部 東京:03-5774-9978 大阪:06-6532-1012URL:http://www.cornes-dodwell.co.jp/Email:e-device@cornes-dodwell.co.jp