On top of the City of East Lansings municipal parking garage, a location which is easily accessibly to the public, I decided to get up close to some cell sites. The garage is directly across the street from a building containing multiple carriers (AT&T and probably Verizon, others) where the garage itself contains MetroPCS, Sprint, and one other (new?) unknown carrier. There are panels all over the place, some of which probably aren't even close to complain ace with regulations. Here are a few of the best pics, with the full set at the link below! Flickr: yankees368's Photostream P1060377 by yankees368, on Flickr P1060378 by yankees368, on Flickr P1060376 by yankees368, on Flickr P1060375 by yankees368, on Flickr P1060374 by yankees368, on Flickr P1060383 by yankees368, on Flickr
Which carrier is using those bigger round antennas in the first pic? Haven't seen that style before..
. Nice. I like how they even the cabling is red. How'd they do that? Cable is usually rubber, and trying to paint it usually doesn't work out too good. Or at least I'd expect the paint to peel and fake off within a year or so On this pic below you can see on the top of the antenna, the top bracket (on the back of the antenna) can be extended to add more physical down-tilt. It doesn't look like there's much (or any) physical down-tilt at the moment (maybe -2° at most). Kind of strange, because it looks like it's kind of high up in a urban area, there probably should be around -6° tilt. But maybe there's some electrical tilt going on inside the antenna that we don't see from outside. . Oh yea, and what's with the round antennas? They aren't omni's, since there's 2 or 3 right next to each other, it wouldn't make sense. But then why a round directional/sectorised antenna? Strange.... Are they maybe "smart" antennas? .
They are indeed smart antennas. It's been explained to me that there is actually an antenna inside of these that can be rotated as the coverage pattern dictates. Every MetroPCS site in this market uses those antennas, usually with a total of 6. So technically, MetroPCS is running a 6 sector setup. They do not use these antennas in the NYC market except for on certain DAS nodes. About those downtilted antennas, I have no idea what was going on there. It seems to be that carriers only sector and there was absolutely no labeling so I couldn't figure out which carrier.
Interesting. Where'd ya get that info? I've heard/read about smart antennas, but haven't seen anyone actually using one yet. From my readings, the directional beam can be changed electronically (ie: no physical moving parts) to follow a user around the area of the cell, in order to reduce interference in the rest of the cell, which helps to improve call clarity, increase data rates, etc. usually in dense urban areas where interference is a problem.
That info is from our fellow member Telcomjunkie. According to him, these antennas can be rotated from either the ground (or even the local office) to mechanically adjust the direction of signal. MetroPCS is the only carrier I've seen use them, however Larry posted a new Sprint site in California that uses them.
Wow, I never heard/read/seen of a mechanical smart antenna. That's not really that "smart" then (maybe a "somewhat intelligent, but still kind of dumb" antenna ), since the beam can only be focused on one user/direction. "Real" smart antennas should be able to focus several beams on several users simultaneously from within the same antenna. But like I said, I never saw one in use, so maybe the practical technology hasn't caught up with the theorists yet
Yea, I guess it is deployed so that they can easily make changes to the coverage pattern as situations dictate without actually having to climb a tower and manually move an antennas.
Don't fret Yankee386... you're well outside the danger zone for exposure. All of those antennas, while close to the general public don't appear to be close enough to do any real harm, especially for the lengths of times people would be nearby in that type of environment. As for painting coax and antennas, it's quite a chore and picking the proper paint is extremely critical. Simply picking a can off the shelf could be devastating to the signal, especially when painting antennas. You have to work closely with your paint supplier to ensure the product will work. For coax, most high quality acrylic paints will stick pretty well. On to those fancy Metro PCS antennas, the antenna they've been deploying have technology in them that allows the azimuth, beam-width on some and electrical downtilt to be changed from the ground. If you look closely, you'll see a third cable, a thin one running with the two coaxes, that's the control line. Some of the manufactuers are even making IP capable modules so that you could modify the coverage pattern from the comfort of your desk. These antennas are slowly taking off here in the US but they're heavily used in the Asian markets, especially Korea.
That's interesting about the cylindrical (MetroPCS) antennas. I had recently noticed them on a MetroPCS site near me and came here to ask about them, and found the question already raised and answered!
Actually their dual freq antennas 800MHZ cellular and 1.9HZ PCS. The give away is the 2 runs of coax coming into the bottom. Most cell carriers own blocks in other bandx
The City of Oakland, California has an almost identical site installation on the elevator penthouse of its City Hall parking garage. I have not had a chance to take any quality snaps of it yet, but I hope to in the next couple of months. -Jonathan PS: Yes, friend, I know I've been away for a while...I'll discuss more in a separate post. -jlk