Reverberant chambers

Shielded chambers

Gtem Cells

Semi-anechoic Chambers

EMC Antennas

Wi-Fi Antennas

 

 


Transverse Electro Magnetic (TEM) cell or Crawford cell (named after its inventor) is used to generate accurate electromagnetic waves over a wide frequency range: DC (0 Hz) to GHz. EM waves generated in the cell propagate in transverse mode and have the same characteristics as a plane wave. It can be used to calibrate E-field broadband probes for testing radiated E-field immunity as well as for measuring radiated emission from a product with a spectrum analyzer/EMI receiver.TEM cell generates a consistent electromagnetic field for testing small RF devices such as wireless pagers, receivers, portable phones, etc. An external test signal applied through the input port of the TEM cell generates a consistent and predictable (plane wave) test field inside the TEM cell. The radiation field emanating from a device (under test) located in the cell can also be detected through the signal generator port  connected to an EMI receiver or a spectrum analyzer. The Equipment Under Test (EUT) is placed on the bottom ground plane as in Open Area Test Site (OATS) and in accordance with the shielded enclosure conditions. TEM cells are used in final compliance certification tests. There IEC 61000-4-3  EMC standard, require a TEM cell for radiated susceptibility and radiated emission tests. Integrated Circuits (IC), Micro Electro-Mechanical Systems (MEMS) devices and PCBs can also be tested according to the standard SAE J1752-3 .  TEM cells can deliver an equivalent OATS performance inside the comforts of a lab with minimum OATS errors. The main advantage of a TEM cell over a strip-line is that in the former, the EUT is completely shielded (except a window to insert/monitor the EUT) from the external environment, thus producing results with negligible errors. It is one of the reasons why a TEM cell is qualified to perform final compliance tests.

Technical Specifications TEM 200 TEM 500 TEM 1000 TEM 3000
Frequency range DC-200 MHz DC-500 MHz DC-1GHz DC-3GHz
Height under the plate 30 cm 10cm 7,3cm 2,35cm
Dimensions (LxWxH) 130x70x62cm 60x30x22cm 54x45x18cm 15x8x6cm
Max. Input power 1,6KW long term 1KW long term 750W long term 400W long term
Field for a 25W amplifier 118V/m 350V/m 475V/m 1,4KV/m
Impedance 50 ohm 50 ohm 50 ohm 50 ohm
VSWR <1.1 <1.1 <1.2 <1.2
Return Loss >25dB >25dB >20dB >20dB
Connector type N N N N or TNC, SMA
Weight Approx. 40Kg Approx. 20Kg. Approx. 4,8Kg. Approx. 1,6Kg.
Options Signal and power supply filter
* Can be equipped with a test setup for IC or PCB acc. to SAE J1752-3


Download – TEM Cell

OPEN TEM CELL

Open TEM-cells are well suited for immunity testing of small objects according to European (CE) and automotive standards (SAE J1113-25) or for biological experiments. The advantage of these O-TEM cells is that they are open and it is very easy to control the functions of the EUT (Equipment Under Test).The applications are for instance the immunity testing of watches, pagers, telephones or PCB’s.In comparison with other closed TEM-cells, the price is low. The field decreases rapidly outside the Open TEM-cells (approx. 33 dB at 1 meter) and it is therefore possible to use an Open TEM-cell in ordinary facilities. Another interesting application is the calibration of field probes as the generated field inside the Open TEM-cell is very exact. Open TEM-cells are the most precise structures for field calibrations.

Technical Specifications O-TEM 200 O-TEM 500 O-TEM 1000 O-TEM 3000
Frequency range DC-200 MHz DC-500 MHz DC-1GHz DC-3GHz
Height under the plate 33,3 cm 14,7cm 7,3cm 2,5cm
Dimensions (LxWxH) 180x160x73cm 97x81x32cm 54x45x16,8cm 44x18x8cm
Max. Input power 1,5KW long term 1KW long term 750W long term 400W long term
Field for a 25W amplifier 105V/m 215V/m 480V/m 1,4KV/m
Impedance 50 ohm 50 ohm 50 ohm 50 ohm
Wave impedance 377 Ω 377 Ω 377 Ω 377 Ω 377 Ω
Connector type N N N N or TNC, SMA
VSWR <1.1 <1.1 <1.2 <1.9
Field precision ± 5 % ± 5 % ± 5 % ± 5 %
Weight Approx. 55Kg Approx. 12Kg. Approx. 3,5Kg. Approx. 3Kg.
Options Signal and power supply filter, Dummy Load.
* Can be equipped with a test setup for IC or PCB acc. to SAE J1752-3

Download OPEN TEM Cells








Automotive TEM filters