Select Fabricators RF Shielded Facility Tents

Structural Aluminum External Frame

Portable EMI Shielded Labs

Series 300

RF Shielded Tent with Vestibule

Rigid Aluminum Framing

Automotive Emission & Immunity Testing in an RF Shielded Tent

1. Internal or External Frame

A free-standing, aluminum channeled, post and beam Series 300 frame supports the weight of port plates, multiple vents for both intake and exhaust, the modular fabric panels and RF anechoic foam panels. Internal frame channels are used to create a clamping system with fabric overlaps to provide an RF tight seal. The patent pending design conductively connects every horizontal and vertical frame member in the system.

2. Metal Ground Plane Floor

An aluminum sheet ground plane system is conductively connected to the frame and modular fabric panels allowing heavy units to enter and exit. The floor plane system uses a rabbet edge design and connected using EMI shielding gaskets and flush-mount clamping bars. The perimeter floor plates contain hardware that clamp to the tent's modular fabric panels which establishes a RF tight seal.

3. Removable Fabric Panels

The removable panels for the modular tent enclosure are made with NovaSelect conductive silver/copper/nickel fabric, externally coated with an acrylic that minimizes particle shedding and metal plating breakdown. The flexible "hardware cloth" is cleanroom ISO Class 7 (Class 10,000 Fed. Std. 209) compatible. Every modular panel has stainless steel grommets installed around the outside perimeter to allow for stud/clamp connection to frame system and aluminum panel floor system.

The single door / double row flexible magnet seal (US Pat. No. 9,029,714) is a separate detachable panel and uses the aluminum bar clamping system on larger size enclosures. Because each panel is conductively connected to each other, the equipment door does not require a threshold, facilitating access.

4. Modular Anteroom

An external anteroom can be added for access once the main door has been secured. The anteroom is permanently attached to a modular panel connecting the unit to the internal frame and aluminum ground plane floor. The anteroom can optionally accordion fold towards main chamber to help minimize the footprint.

External anterooms include the standard conductive fabric floor with heavy duty vinyl protective layering on top and bottom. All four walls and ceiling inside the anteroom can be covered with optional lightweight fire barrier or ESD material.

5. Anechoic Foam Panels

Anechoic foam panels are installed on internal frame system as needed. Encased when specified, to prevent shedding and comply with ISO Class 7 (Class 10,000 Fed. Std. 209) cleanroom specifications,

RF Isolation Enclosures for Oversized Applications: The Big RF Tent

RF / EMI testing of aircraft and large electronic intensive military vehicles can be a three ring circus, posing unique product development challenges. The Big RF Tent is an affordable way to reduce large capital outlays constructing oversized permanent RF / EMC testing chambers, and the complex logistics and time delays using off site testing labs or open area test sites (OATS).

For large vehicles and aircraft, the total installed system needs to be tested for EMI susceptibility and also for emitted RF radiation for FCC compliance. Tuning and calibration is also important with the whole system installed in the vehicle.

Select Fabricators extra-large RF shielded tents offer an innovative way to assure all the electronic and wireless components as installed in the aircraft or vehicle are fully RF / EMC tested, and sensitive electronics are properly calibrated.

Select Fabricators has designed and built RF shielded tents for aerospace and military applications as large as 45'L x 30'W x 19.5'H, and can research the feasibility of larger RF shielded tents if required. These very large, highly engineered, customized RF tent enclosures are constructed of metalized conductive fabric with permanent or collapsible frames, RF filters, and are complete with air-conditioning. RF / EMI tents provide shielding ratings of -85dB from 400 MHz to 18 GHz to meet your testing and calibration requirements. Some applications also include foam to dampen internal reflection.

The cost of these extra large tents is a fraction of a hard walled chamber of this size. Additionally, when the product development project is complete, these tents are designed to be readily taken down and stored for future use, or shipped to be used for another project at another location. This saves significant square footage of valuable space, and may avoid the high cost of building and housing duplicate oversized chambers in multiple locations.

Aerospace product development applications for extra large RF tents include RF susceptibility testing of the entire system and testing for radiated RF emissions from the system. The United States Military's Standard MIL-STD-461F appendix A states:

When equipment is too large or requires special provisions (loads, drives, water, emission of toxic fumes and such), testing in a typical semi-anechoic room may not be feasible. Temporary screen rooms consisting of hardware cloth can be built around the test area to reduce the ambient for radiated emission testing and to contain the RF field during radiated susceptibility testing. Since the room may be highly reflective, care must be taken to identify any resonances. Several antenna positions may be required in order to reduce the effect of the resonances.

Extra large tents also allow calibration and tuning of sensitive electronics in large aircraft and vehicles during product development, free from outside interference. For calibration of electronics installed in large military vehicles in the field, these extra large RF Tents can provide outdoor portable RF isolation.