The weirdest (but working) iPhone 4 reception trick I have ever heard

It points out that some antennas for PCBs are built at 1/4 wavelength (from 2.75 to 1.3 inches for GSM networks). Something to do with this combined with how waves are either reflected or refracted when hitting a surface like glass could explain how (depending on the angle of the glass and its length) you could see a portion of the signal actually directed upward or just in a different direction. Maybe combined with a flat metal table as a shoddy groundplane?

Whatever is going on it's probably limited to the signal inside and above the glass, as going through non-tinted glass is (iirc) supposed to have a -3dB reduction in signal.

More reading: http://setup-wireless.blogspot.com/2008/11/radio-frequency-b... http://docs.google.com/viewer?a=v&q=cache:FGiX56l9G3MJ:w... http://www.wifi-doc.com/Cisco.Press-802.11.Wireless.Ne/15870...

(i really wish an RF/electrical engineer would comment!)

Any suitably insulating (capacitive) enclosure (such as a "napkin swan", teacup, etc.) which preserves a largely vertical orientation (perpendicular to the local ground plane) should work just as well. We're still comfortably within the far-field http://en.wikipedia.org/wiki/Far-field performance envelope for transmission, but well within transmission-line power transfer regimes at these frequencies with a cell-phone-sized antenna.

If the glass were lead crystal (extremely unlikely in the bog-standard bar tumbler pictured), there's more potential for interference and a spatial locus of signal above the noise floor is possible. Typical window and utensil glassware is essentially transparent to these frequencies.

There's no cell coverage in my basement. Sometimes you'd get 1 bar, but it will drop soon afterwards.

After putting the phone inside a glass, I have 3 bars. I took it out, held it by the charm (is that how it is called? The little string with a little figure that you can put on most phones today) and coverage dropped to 0.

Works for me.