Not really weird. There's a boundary there between the air in the glass and the glass itself. So you've got a dielectric boundary and you'll get some reflection going on inside the glass. Lots and lots of things reflect radio waves to a certain extent. I'd guess that's what's happening here.<p><a href="http://en.wikipedia.org/wiki/Non-line-of-sight_propagation#Reflection_losses_at_dielectric_boundaries" rel="nofollow">http://en.wikipedia.org/wiki/Non-line-of-sight_propagation#R...</a>
If you stick it in a pint glass it makes the speakerphone a lot louder as well.<p>I can foresee some funny looks from strangers however, if you were to sit there in a bar on your own shouting at your phone in the bottom of a glass. Maybe that kind of thing is normal in california, I have no idea.
I suspect this is more about isolating the phone from the radio energy sinks of the human body (surface moisture on the skin & saline blood plasma) than anything to do with the glass itself.<p>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 <a href="http://en.wikipedia.org/wiki/Far-field" rel="nofollow">http://en.wikipedia.org/wiki/Far-field</a> performance envelope for transmission, but well within transmission-line power transfer regimes at these frequencies with a cell-phone-sized antenna.<p>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.
This is questionable. A couple stray observations for the boffins at HN:<p>1. Confirmation bias. Sure it works, because when it doesn't we don't think about it or publicize it on the net.<p>2. Glass holder removes your big meaty hand from the equation. Your hand absorbs radiation and is the equivalant of wrapping a phone in a steak.<p>3. Only works because the iphone radio is such a mess. You may be looking at bar strength changes that are happening anyway.<p>4. Works but because of orientation. Holding up compared to laying it down may give you better reception.<p>5. No controls. He should try this with a plastic holder or hanging it in the same orientation with a string. I wish the "aha I discovered something amazing" crowd would learn what controls are.
So, he's in this uber cool restaurant, spending a nice evening with his daughter. And the first things he thinks of? Yeah, "checking in" and "tweeting". Am I the only one who finds this sad?
Tested with an Apple Bumper case and a 500ml Arcoroc glass in my apartment: no effect.<p>Tested without the Bumper: still no effect.<p>Perhaps only certain kinds of glasses will work? Certain shapes or sizes?
I'm going to risk sounding like a dunce here, but IIRC some frequencies are more prone to bouncing off glass - for example in metropolitan cities with lots of high-rise buildings. While this is a detriment in the city, it could also be acting as a "satellite dish" making it easier to collect stay signals while also directing most of the transmission upward. Considering the antenna is supposed to be at the bottom of the phone the effect should be more pronounced as more of the glass can be used to direct the signal.<p>Am I crazy?
If you don't have a glass nearby, this also works when putting your 3GS (and probably other phones as well) at the same angle inside an upside-down clear plastic CD spindle cover. Went from 2 to 4 bars. Took the phone out, dropped down to 2.
It probably has more to do with antenna response characteristics due to polarization (antenna is similar to a j dipole <a href="http://en.wikipedia.org/wiki/Slim_Jim_(antenna)" rel="nofollow">http://en.wikipedia.org/wiki/Slim_Jim_(antenna)</a> or a modified inverted V (since it's a U) maybe <a href="http://en.wikipedia.org/wiki/Inverted_vee_antenna" rel="nofollow">http://en.wikipedia.org/wiki/Inverted_vee_antenna</a> ) + isolation from your hand. Without your hand (which is similar to a non-efficient ground plane) screwing up the antenna response, a vertical iphone would likely have better reception, <i>especially</i> if it's a dipole-like.
I wonder, is the glass just holding the phone at the right angle for the polarity of the phone's antenna and the available signal to match up? If so, this trick wouldn't likely work places other than that restaurant.