contact comtest engineering

3m semi anechoic chamber

The main purpose of a 3 m semi anechoic chamber is to perform measurements of radiated emission and/or immunity at 3 or 1 mtr test distance. The combination of the pan-type 2mm galvanized panel system, parallel closing RF shielded doors and polystyrene hybrid absorbers on the walls and ceiling creates a high performance controlled electromagnetic environment that complies with international immunity and emission test standards. The 3m semi anechoic chamber is a multi functional EMC test facility for commercial, military and automotive testing.

Features of a 3m semi anechoic chamber:

  • Full compliance emission test site for frequency range of 30MHz to 18GHz as per CISPR 16-1-4
  • Full compliance immunity test site for frequency range of 80MHz to 6GHz as per IEC/EN 61000-4-3
  • Shielding effectiveness according to EN 50147-1 (>80dB at 10kHz)

Applicable standards / test methods for a 3m semi anechoic chamber:

  • CISPR 16-1-4
  • IEC/EN 61000-4-3
  • EN 50147-1
  • ANSI C63.4
  • FCC 15

Typical performance of a 3m semi anechoic chamber:

  • NSA: +/- 4.0dB
  • sVSWR: ≤ 6dB
  • FU: 75% of 16 points ≤ 6dB at 3m test distance & 1,5 x 1,5m test window (0,8m above floor level)


Typical specifications for a 3m semi anechoic chamber:

Entrance door
Wall entry panel
EUT power line
Frequency range
Test distance
Test volume*
Turn table
Antenna mast             
8.55x5.55x5.325m (l*w*h)
2mm ZMA-140 galvanized shielding panels with a free standing structural steel support
Hybrid solution of ferrite tiles and polystyrene hybrid absorber (model HT45) on walls and ceiling
Honeycomb model 1791-3030 (300x300mm / 18GHz)
RF shielded swing door model 1766-1221 (1200x2100mm)
Model 1795-1530 (150x300mm) including RF connectors
Filtered 230VAC / 32A / single phase model 4801-032
CDMT lights 70W model 1840-070
30MHz to 18Ghz for radiated emission and 80MHz to 6GHz for radiated immunity
3m between centre of antenna and EUT
Reflective ground plane with floor entry panels incl. RF connectors
Fiber optic controlled turn table 2m diameter
Fiber optic controlled antenna mast

* other test volume dimensions available upon request.

In addition to the typical specification of the 3m semi anechoic chamber Comtest can tailor the chamber’s specification to satisfy our customers’ individual requirements.

Options for a 3m semi anechoic chamber:

  • An additional shielded room can be installed to house high power RF amplifiers (amplifier room) or control and test      equipment (control room).
  • Video and audio monitoring system: color camera unit with remote controller and LCD monitor.
  • RF shielded sliding door model 1754-2424 Sa (2400x2400mm) incl. lift platform for large EUT entrance.