TEM Devices /
5503 Electric Field Generator
- Generates large area uniform vertical electric field
- 10 kHz - 30 MHz frequency range
- Accommodates various EUT sizes with adjustable height feature
- Temperature maintained with external forced-air cooling, and monitored by temperature sensor
- Easy to assemble/disassemble and remove from the chamber
This E-field generator features a frequency range of 10 kHz to 30 MHz and generates a large area uniform vertical electrical field. The Model 5503 top plate consists of four separate tube conductors that are connected in parallel at the feed and load ends. This four-wire transmission line acts as a plate conductor at frequencies up to 30 MHz. A vertical, quasi-static TEM mode electric field is produced between the four-wire system and the ground plane of a semi-anechoic chamber. The width-to-height ratio of the "four-wire plate" is designed for an impedance match to a 50 ohm system without an input transformer. An external forced-air-cooled load is used to terminate the Model 5503. The cooling system maintains proper operating temperature and is monitored by a temperature sensor. The load housing is connected to a plate in the chamber floor. A pulley systems allows users to manually adjust the height to accommodate various equipment under test (EUT) sizes. The E-field generator is easy to assemble and disassemble, and can be removed from the chamber when needed.
Electric Field Distribution
The ETS-Lindgren Model 5503 field generator generates a vertical electric field between the transmission lines and the metal ground plane of a semi-anechoic chamber. The electric field distribution is modeled and optimized numerically and experimentally. The transition regions are designed to suppress higher order modes of electric field, which makes the Model 5503 suitable to operate at high frequencies while maintaining a large uniform area. The electric field distribution is computed by Numerical Electromagnetics Code II (NEC 2). A 10 kW RF input power is assumed. A full numerical model is utilized, so no assumptions are made regarding the input impedance or any other electric properties of the field generator. The height is adjustable during vehicle testing. Generally, field strength is higher for lower conductor heights. Field distributions for typical frequencies and heights are shown here. Additional data are available upon request.
The Model 5503 is suspended from the chamber ceiling with nonconductive ropes. Manual height adjustment is achieved with a pulley system. The conductors are made of 2” OD aluminum tubing with Kwik-Flange . connectors at each end. Typically, the flat central section is assembled on the floor and then lifted into place with the ropes. The I/O end tapered sections are then attached to the flat central section and grounded to floor plates. After testing, all tubing can be disconnected and the unit may be removed from the chamber.