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CISPR-25 anechoic chamber

The main purpose of a CISPR-25 anechoic chamber is to perform measurements of radio frequency emission or immunity specialized for vehicle on board equipment testing. The combination of the pan-type 2mm galvanized panel system and the polystyrene hybrid absorbers on the walls and ceiling eliminates unwanted electrical noise and complies with automotive emission test standard like CISPR-25.

Features of a CISPR-25 anechoic chamber:

•    Noise floor level as per CISPR-25 requirements
•    Grounded EUT test table as per CISPR-25 design guide lines
•    Noiseless CDMT lights to meet the stringent requirements of CISPR-25 noise floor level

Applicable standards / test methods for a CISPR-25 anechoic chamber:

- CISPR-25
- CISPR 12 / EN55012
- ISO 11452
- SAE J1113 part 21
- Automotive directive 95/54/EC
- Various ISO standards for automotive
- Specific test standards by Automotive manufacturers

Typical performance of a CISPR-25 anechoic chamber:

- Absorber return loss of 6dB minimum between 70MHz and 6Ghz.

Typical Specifications for a CISPR-25 anechoic chamber:


Personnel Door:
Wall entry panel:
EUT power line:
Frequency range:
Table support:
6.30*5.40*3.825mtr (l*w*h)
2mm hot galvanized shielding panels with a structural steel support on the roof panels
Ferrite tiles and polystyrene hybrid absorber solution (model HT25) or model MT65
absorbers on walls and ceiling
Honeycomb model 1791-3030 (300 x 300mm / 18GHz)
RF shielded swing door model 1766-1221 (1200*2100mm)
Model 1795-3030 (300x300mm) including RF connectors
Filtered 230VAC / 32A / single phase model 4801-032
CDMT lights 70W model 1840-070
70MHz - 2.5GHz
Conductive metal ground plane
RF-grounding connections to the shield wall or floor for test table cover connection

In addition to the typical specification of the CISPR-25 semi anechoic chamber we are able to tailor the chamber’s specification to satisfy our customers’ individual requirements.

Options for a CISPR-25 anechoic chamber:

•    An additional shielded room can be installed to house high power RF amplifiers (amplifier room)or control and
     test equipment (control room).
•    EUT door: Shielded sliding door model 1754-2424 Sa (2400*2400mm) incl. lift platform for full vehicle testing
•    Video and audio monitoring system: 2 pcs color camera units with remote controllers and LCD monitors.
•    EUT test table with connection strips.
•    To test below 70MHz the absorber solution must be a hybrid solution of ferrite tiles
      and HT25 absorbers.