bohemiancoast: (Default)
bohemiancoast ([personal profile] bohemiancoast) wrote2011-02-01 07:20 am

AKICIF: Subways

Which US cities have underground railways?

Background -- so, yesterday I was hacked off at one of the many ways that the iPhone is rubbish if you're outside mobile phone reception, and concluded that nobody with any influence at Apple had any experience of commuting by underground.

Edit: [livejournal.com profile] mr_tom has pointed out that some of the US urban railways are so close to the surface that mobile reception is maintained. So, I think I mean 'which US cities have underground railways that break mobile phone reception'.

And yes, I think I already knew that Cupertino was a driving sort of place.

[identity profile] voidampersand.livejournal.com 2011-02-01 04:01 pm (UTC)(link)
I think Apple people are very familiar with San Francisco. BART runs in a deep tunnel. On Market Street the stations are under the street. Muni Metro is under the stations. BART runs under the Muni Metro. It's about six stories down. BART's transbay tube is pretty far down too, under water. The Muni Metro K, L, and M lines continue from Market Street through the Twin Peaks Tunnel to El Portal. Twin Peaks is the big mountain in the middle of the city. If I recall correctly, it's about ten stories from the station in the middle, down to the tracks.

The North and South Halls of the Moscone Convention Center, where MacWorld occurs, are underground. The North Hall has a park on top of it. Cell phone reception has been an issue in the halls until the phone co's put a lot of cells in.

Getting radio into a deep hole in the ground is a hard problem. You need lots of cells. Or you can put wifi or microcells in the cars, but then you need to get the broadband data to and from the cars. Also, subways during commute time are packed with users, and cell performance degrades a lot with more users, even on the surface.

Apple could improve reception by building in a whip antenna, instead of the built-in active antenna. But that probably would not go over well with the style-conscious crowd. And it would not help that much in places where cells are lacking, or where the number of phones is overwhelming the cell capacity.

[identity profile] jamesb.livejournal.com 2011-02-01 11:15 pm (UTC)(link)
We have phone reception on our line (heathrow express/connect) all 3 miles of it, 23 metres underground, although Tmobile is a bit crap at termibal 4.