Cellphone tower coverage Qs [Telecom]

See the notes on the site. It mentions that it doesn't have listings for towers that are not registered in the fcc database, nor for towers owned by third parties. It also dosen't have listings for carriers co-located on another carriers tower. I'm guessing that they are basing the database on the FCC Antenna Structure Registration, and not a specific transmitter site license. I'm not sure if individual cell sites are even listed in the FCC DB. I suspect that Nextel sites are more likely to be listed, given that Nextel is/was a SMR licensee with interconnect capabilities, and not a cellular licensee. Different service, different rules.

I know of at least one tower (at Foothill College) that is not shown on the map. I forget who is actually on that tower, but there were at least

3 carriers when I last looked. The site is owned/leased by one of the site management companies (Spectrasite?), and not by a specific carrier.

It is likely that there are additional cell sites that are not located on a tower at all, but are installed on the roof of a building (there is a office building along El Camino, next next to WalMart and Trader Joe's which I recall as having antennas on it.)

Other places where you may find antennas include flagpoles (there are examples at Palo Alto fire stations 3 (Rinconada Park), and 4 (Mitchell Park), lamp posts (the old Elks Lodge parking lot next to Dianah's), and church steeples. There are also some micro sites mounted on utility poles (Junipero Serra @ Stanford Ave).

I know Jeff Leiberman has/had a list of cell sites in the San Lorenzo Valley area, but I haven't looked at it in quite a while. I don't know if it lists anything down in the Santa Clara Valley.

Red-faced, thank you! I now see those notes. :-)

It's possible those "undocumented" towers at Foothill College and other sites north-westwards is probably why I get the CHP's 911 dispatch while along I-280 instead of the local municipalities' 911 centers.

The 20 mile "gap" between Los Altos/Mountain View and Burlingame as depicted on cellreception's site was puzzling, especially so given all the hills and other radio obstructions along I-280.

Again, thank you for the info!

I'm going to poke around and followup if/when I find sites with better/more information. It's odd (to me) the FCC wouldn't have ALL cellphone (tower) transceivers in their database given how tightly they seem to regulate the spectrum.

It seemed a bit odd at first that there isn't a single tower shown in Saratoga, when I drive by plenty of them here every day. But most of the towers here are actually owned by Crown Castle, and they lease space to the different carriers. So it looks like they wouldn't be listed.

I still find it odd the FCC doesn't require all cell phone sites to be registered with the FCC. If they are registered, most are not publicly revealed.

With that written, I hope you're sitting down. :-)

I finally located a site showing all the cell phone towers and/or sites in the SF Bay Area. AT&T has 1,150, T-Mobile has 1,550, etc.

Here's the info site:

and here's a map of AT&T and T-Mobile cell phone sites as of 25-May-2009; AT&T sites are blue (or green if requiring more research), T-Mobile sites are pink/purple (brown if more research required), and note it takes awhile to place that many "push pins" on the Google map:

Now THAT (the map) makes more sense than the obviously w-a-y incomplete FCC database.

The cell sites appear to be every 0.5 to 1 miles in dense populated areas and/or along major roadways, and I now know how/why I reach the CHP the moment I enter I-280: there's a tower/site right there and they continue flanking I-280 every 0.5-1 mile as far north as I care to drive. And when I'm at home there's a closer tower, so that explains why I get the local city's 911 center and also (presumably a legacy from Cellular One) a tower site nearly flanking the food supermarket which I suspect was in response to my complaint years ago (circa 1993).

According to the author of sfocellsites, AT&T keeps their sites secret, so he has to discover them the hard way.

Would anyone know what the sizing was in the early days of analog cellular service?

I remember that [while] digital phones got popular they had many dead spots and [the cell companies] had to install many more towers since the digital signals didn't propagate as well (or were more easily blocked).

Is there any reason for the _general_ public to know where cell towers are? I think it's probably something that should be kept quiet; perhaps limited to those within the communications industry who have a technical need to know, or those experiencing radio interference from a too-close tower. AFAIK, the location of a cell tower is only one of many factors regarding quality of service.

***** Moderator's Note *****

Members of the general public who are deciding which cellular carrier to use are certainly entitled to know the signal levels each carrier offers at the places they will be using the cell phone. If the cell site's longitude and latitude can be used to obtain that information, then I'd say "Yes, they're entitled to know".

Of course, cellular company executives might feel that their advertising programs are a more accurate source of information for consumers, so I understand that they may be reluctant to disclose the exact locations for their cell sites.

At one time (early 1990s) Cellular One was quite open as to the location of their cell towers. Each month's billing included a new coverage map with tower locations highlighted. I thought I had kept the old maps and could scan one, but I cannot find any in my files.

Similar problem with the DTV transition from analog: either you get the signal or you don't.

Additionally, early digital voice quality was horrible and many people who had dual-mode phones (analog/digital) optioned their phones to operate analog-only solely for the voice quality.

Several folks earlier this week posted URLs to websites having photos of cell towers/sites, and what surprised me was many sites' vulnerability with open-to-the-world cabling, etc.

For me, learning the locations of nearby cell sites yesterday answered my question which 911 response center I would reach when dialing 911.

Agreed! I also, uh, downloaded the database from sfocellsites.com and fed in the lat/lon data to one of my programs to get the bearing and distance to the four closest towers to my home; the 416, 427, 2037 and

3616 are the designators displayed by hovering my mouse over the "push pins" on sfocellsites' Google map and here are the results:

GREAT CIRCLE CALCULATOR, GCDIST 1.1 Copyright 1987 by Thad Floryan

From: 37° 20' 17.2"N, 122° 04' 17.1"W Home To: 37° 19' 58.5"N, 122° 04' 31.9"W 416 Bearing = 212° 09.8', Distance = 2239.9 feet

From: 37° 20' 17.2"N, 122° 04' 17.1"W Home To: 37° 19' 56.1"N, 122° 03' 04.1"W 427 Bearing = 110° 00.0', Distance = 1.0 nm, 1.2 miles

From: 37° 20' 17.2"N, 122° 04' 17.1"W Home To: 37° 19' 29.0"N, 122° 04' 22.8"W 2037 Bearing = 185° 22.1', Distance = 4906.4 feet

From: 37° 20' 17.2"N, 122° 04' 17.1"W Home To: 37° 20' 32.0"N, 122° 04' 22.5"W 3616 Bearing = 343° 45.9', Distance = 1557.5 feet

The average cell phone user would be unlikely able to use location data for anything meaningful. :-)

Yes, the public is entitled to know signal strength where they'll need to use the phone.

I'm not a radio expert. But I strongly suspect tower location is only one of several factors that determine signal strength at the cellphone. I believe terrain plays a role. Also, tower capacity may be important--if a tower is 'filled' or down, another more distant tower will be used.

I believe the list mentioned tracked via Antenna STRUCTURE registrations [ASR]. {aka "towers"}. ASR cares not about antennas, only things that hold them up. I assumed that the Universal Licensing System [ULS] database tracked cell sites transmitters but maybe they fall under some blanket scheme as do mobiles. [In the business 2-way world; the base station has one license, the mobiles a separate one. The base station has a specific address; mobiles a city, state or region, or in very few cases, nationwide. AT&T Long Lines and Red Cross were two of those...]

Note that the FCC does not even notice USGovt users/sites. There's a tower in zip 20607 that Dept of Homeland unSecurity recently built; it has no ARS registry #; no ULS signs, etc.

-- A host is a host from coast to snipped-for-privacy@nrk.com & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433

***** Moderator's Note *****

U.S. Government frequency assignment are managed by a different agency: IIRC, the National Telecommunications & Information Administration.

[[.. munch ..]]

The _tower_sites_ database is just that. It idents the places where special construction has gone on. RF 'towers' are not subject to local zoning, etc. restrictions -except- as the Feds allow. (Ask _any_ community that has tried to 'outlaw' ham radio antennas :)

You have to get "permission" from the Feds to build a tower (over a specified height) in the first place. And (again, over specified height) 'operate' that tower in accord with Fed requirements (mostly as regards lighting the structure).

Once constructed, you can hang pretty much _any_ other transmitting/receiving gear off it without needing any additional 'permission' as regards the tower. If it is TX gear that requires a license, yes, you do still have to get that operating license -- but the 'transmitter/antenna location' part of that license application is just a formality; consisting essentially of "on the site of {callsign} transmitter/antenna".

I'm not disputing what you wrote, but my observations locally differ. It seems every time a communications tower is proposed it has to be reviewed and signed- off by the local cities after public review as I read in the local newspapers.

With that written, when I erected this tower in 1967, no permits were required. A neighbor has a similar tower and AFAIK no permit was required. Neither of us have been hassled over our towers to date.

A HAM friend, John Cronin (K6LLK, ), erected a 100' tower for his HAM rig and I don't recall him ever mentioning any legal or other hassles.

It still seems truly odd the FCC would regulate (and place in the database) the tower structure and not the actual carriers' (cell phone) transceivers.

Just curious: do you have any why the Feds, and not local governments (with the exception I noted above), are the regulators of the structures? I'm not having any success Googling an answer to this question.

I fully understand why the FCC would regulate devices using radio spectrum in compliance with international agreements.

I'm still bewildered why the FCC wouldn't insist knowing the locations of all carriers' cell phone transceivers regardless of tower or other mounting. :-)

...

That's not entirely true. In Saratoga (and probably other cities too), any cell tower that's visible to the public has to get a city permit, and go through a public meeting for approval. Even a change to an existing tower as small as modiying the shape of the antenna panels or the size of a visible equipment cabinet has to go back through the permit process.

They can - and have - refused to allow antennas in certain locations that were considered eyesores. But they can't refuse based on any technical concerns, the FCC doesn't allow that.

Ham antennas are different - the FCC specifically requires local zoning codes to allow them.

***** Moderator's Note *****

Ham antennas _are_ different, but (much as we hams may wish otherwise), local governments are only required to make reasonable accomodations for ham antennas: the FCC doesn't usurp local authorities outright. Moreover, ham operators have _no_ relief from the provisions of "CC&R" agreements, which are becoming the norm on nearly all new construction, and which routinely forbid exterior antennas. Paradoxically, the FCC _has_ usurped CC&R restrictions on TV antennas, feeling that the public's right to watch the Bachelor show is more important than contractual restrictions against eyesores.

In 1960 in the San Fernando Valley area of Los Angeles, I challenged the CC&R at my parents home for my radio antenna/tower. I first went before the city Council, [but] that did no good, so next we went to court: I won that case and my tower stayed. I took it down when I moved years later. In 1971, after the Sylmar earthquake [I] helped many people keep in contact with other parts of the company, so the neighbors were happy and never said a word about the tower again. Working for GTE at the time, I was working around the clock, but managed to find time.

Hams have asked the FCC to usurp CC&R's for ham antennas like they did for TV receiving antennas. The FCC refused. The FCC argued that CC&R's are private agrements that they have no basis to strike down. But they had no problem doing just that for TV antennas. I guess the broadcasters had more money to fight these restrictions than hams have.

However, in the decision refusing to override CC&R's for hams,the FCC indicated that they would be open to usurp CC&R's for ham antennas if Congress orders them to.

In the current legislative session, HR 2160, the "Amateur Radio Emergency Communications Enhancement Act of 2009",

... directs the The Secretary of Homeland Security to: "(2)(A) identify unreasonable or unnecessary impediments to enhanced Amateur Radio communications, such as the effects of private land use regulations on residential antenna installations; and

(B) make recommendations regarding such impediments; and

(3)(A) include an evaluation of section 207 of the Telecommunications Act of 1996 (Public Law 3 104?104, 110 Stat. 56 (1996)); and

(B) make a recommendation whether that section should be modified to prevent unreasonable private land use restrictions that impair the ability of an amateur radio operator licensed by the Federal Communications Commission to conduct, or prepare to conduct, emergency communications by means of effective outdoor antennas and support structures at reasonable heights and dimensions for the purpose, in residential areas."

***** Moderator's Note *****

At first glance, this might not seem related to telecom per se, but I allow posts about some Amateur Radio issues, for several reasons:

1. Governmental actions that limit Ham Radio antennas give clues to the current administration's views about radio use by other services, such as WiMax.
2. Federal and local governments who allow private contracts to take the place of the (often unpopular, and always noisy) lawmaking process are subletting their jobs to corporations, and I think such laziness should be brought to light.
3. Ham radio is sometimes a bellwether for other, commercial uses of radio: e.g., hams developed the first practical packet data transfer networks using radio. FCC treatment of hams sometimes reflects the biases and fears of the industries which lobby the FCC to vote their way.

The Antenna Structure Registration Number issued by the FCC is only required on structures that require FAA notification (generally those higher than 200 feet, see

.)

This requirement is in part 17 of the rules, which regulates tower lighting, painting, etc. to minimize the hazard to aircraft.

It APPEARS that cellular systems are licensed on a market or other geographic area basis. Licensees are allowed to add transmitters within that area (see

). All the cellular rules are listed at

Harold

Great references! Thank you very much.

Upon thinking more about it, it's somewhat analogous to placing more WiFi WAPs in one's home or office to provide better "local" coverage. In other words, it's the service, not specific cell phone transceivers, that's regulated.

And for those of us who are really curious, we rely on the efforts of others, such as the operator of sfocellsites.com, to locate the transceivers.

comp.dcom.telecom is really a great resource! :-)

I repeat, "Except as the Feds _allow_." They can choose to allow local review for some kinds of stuff.

Yup. The rules get _messy_, but that unit is clearly under the limits at which any Fed agency gets "interested". There's a watershed point at something like

50' (100'??) above the highest point in the 'immediately surrounding terrain'.

Hams _do_ have special dispensation in a _lot_ of the FCC rules. The _FAA_ requirements for tower lighting, and height restrictions near airports =do= apply in full, however.

"Why the Feds" is because the Federal government claims _exclusive_ authority over the regulation of RF spectrum, _licensed_ station equipment and the operation thereof. RF towers are considered 'part' of the station equipment, and thus under exclusive Fed control. Prevents local governments from attempting things like 'taxing out of existence' an operation that is 'politically unpopular'. It's the _same_ authority that allowed the Feds to rule that local govt and/or private associations could _not_ ban or other- wise restrict the placement of 'small dish' satellite receivers.

There are multiple Fed agencies with applicable regulatory authority. With _rare_ exceptions (i.e. amateur radio service), anybody putting up a tower has to go through FCC licensing hoopla, so -- since they're 'already handling it' -- they got stuck as the point-of-contact/coordinating agency. A lot of the requirements/restrictions on towers actually come from the FAA. They're the ones that require lighting at 300', and limit the buildable height within many miles of an airport, etc.

Who says they don't know? "Knowing", and "publishing", are two _very_ different things.

Has to do with the airspace, navigable or otherwise. Federal Aviation Regulations are the biggest part. Lighting, as mentioned, is a -big- issue. The advent of the ubiquitous medical helicopter has reinforced the enforcement (gag, sorry for that sentence...but am sure you get the idea ;))....

There is hardly any 'uncontrolled' airspace left in the USA. Some places in very remote (but NOT mountainous) areas are exempt, [and] then only [from ground level to] 500 above the ground; deserts/lakes/ open prairie hundreds of miles from a town, that's about it anymore. But be careful, if there is a human around any of those remote areas, airspace rules change and [the airspace] can be controlled..again. About the only complete exception is when you can use the phrase: "...excepting to take off and land" (a FAA legal term of art) then you can use the airspace....but towers don't do that, do they.. :)))