In my experience the tile lined chambers will meet site attenuation if appropriately sized. You must be able to do the 4 meter height scan. The larger the chamber the better the site attenuation is likely to be. Another factor that comes into play is the use of geometric antenna factors for site attenuation inside a chamber. That is different factors for polarities and antenna heights. This is not always done on an OATS. I understand that the folks at the C63.4 working group are looking at including a chamber NSA method in the standard. This method supposedly will not allow this type of factor, but will have a different theoretical curve. I don't know any details about this, or what the status of this work is. Does anyone know more about this?
From: Roger Hsu [mailto:[email protected]] Sent: Wednesday, March 24, 2004 1:24 AM To: [email protected]; [email protected] Subject: Semi-anechoic chamber Could the semi-anechoic chamber meet the NSA requirements from 30MHz to 1GHz per ANSI C63.4-2000 for full compliance testing which only constructed with Ferrite Tile? i.e. without Foam Absorber. Does Foam Absorber play an important role at the lower frequency (30MHz) or it is only for above 1GHz? Regards, Roger
