Title
Cell Sites in California


Author Information
Amber Kelly
American River College, Geography 350: Data Acquisition in GIS; Fall 2009
Contact me at W0776851@imail.com

Abstract
For the numerous amount of cell sites in the state and the danger that they pose it is surprising that our emergency services department does not have a layer containing this data. The data used in this project was obtained from public sources and is accessible by everyone. The resulting data for the state was more than could be addressed by this small scope project and thus I focused my mapping on Sacramento.


Introduction
For all of the data that the office of emergency services has it does not have a layer of the cell towers of California. This layer could be a valuable resource in the case of a disaster. All too many Americans rely solely on their cell phones in this digital age and if that lifeline were cut off they would be entirely without communication. The upgraded terrorist threat makes this layer even more valuable as these towers represent a greatly overlooked target that would maximize the effectiveness of a terrorist strike. The information for all of these towers is partially contained within the FCC database and partially contained within other databases including those of the cellular carriers. This wide spread of data sources presents a challenge in creating a cohesive database for the state of California. Because of the extensive nature of the data my project will be limited to the scope of Sacramento.


Background
The FCC database is publicly available for download, and while not the most user friendly of data it is a complete source of towers registered with the FCC. City-Data.com provided a large amount of the data for this project through individual city pages. Additional sources of data include the AT&T Towers database downloaded from their website.


Methods
All data used in this project is available to the general public. No proprietary sources were utilized.

The FCC database lists all towers registered with the FCC and publishes it on a weekly basis. It can be easily downloaded but does not contain lat/lon coordinates. It does however contain addresses that can be put into a mapping program to divine the lat/lon. Though with over 130,000 records for California this would take a considerable amount of time to do, far more than I had during the time of this project.

City-Data.com has cell and antenna towers listed on the page for each city in California. The data is in text format and requires considerable processing to be ready for use in ArcMap, but is readily available and easy to find.

 AT&T Towers has a downloadable database of all of their towers which can be easily reduced to just California data. It is preformatted to be easy to use and understand. This was, by far, the most user friendly data I came across for this project.

Results

The table below is adapted from the City-Data.com data. Once converted from text to delimited it could be imported into excel and turned into organized, useful data. This simple format of Name, Lat, Lon, Type, Height is continued by listing the Registrant and their information. It was chosen for its ease of conveying important information.

Name

Lat

Lon

Type

Structure Height

Overall Height

Freeport Water Tank, 7788 Freeport Blvd.

38.474917

-121.505778

 

 

 

8500 Carbide Ct.

38.474972

-121.391

Pole

16.8 m

 

ROBERT W BERGER, 1811 22nd Street

38.566389

-121.480833

Tower

96.3 m

100.6 m

5331 Walnut Ave

38.663611

-121.348611

Tank

53.6 m

53.6 m


The AT&T Towers data was arranged in a similar manner with slightly more data included.

BUENA VISTA

19131 MILLUX ROAD

Bakersfield

Kern

93314

35.17916667

-119.1313889

COFFEE ROAD

34718 7TH STANDARD RD

Bakersfield

Kern

93314

35.45027778

-119.1008333

ROSEDALE WEST

13952 ROSEDALE HWY

Bakersfield

Kern

93314

35.385

-119.1572222

 

The map base data did not require any transformation as it was retrieved from CalAtlas in shapefile form.

Figures and maps

Closeup of the Sacramento Area and the AT&T Towers.

Sacramento Area with FCC registered cell and antenna towers in addition to AT&T Towers.

Same map with background data to show how sites are located in relation to roads and water features.


Analysis
This experience in data acquisition enlightened me to the massive amount of data kept on file about the towers and cell sites of the state. It still troubles me that there is no layer for CalEMA to use or to give to our local emergency services but it is good to know that one can be created with a lot of time and a considerable amount of dedication. The text data was successfully converted to a useable format and the table data was useable from the beginning. It was surprising that the FCC does not keep lat/lon coordinates for the towers and unreasonable to consider converting it. It would be interesting to see if an address locator could be created to provide the coordinates for the addresses provided by the FCC.

Conclusion
It could be very beneficial for the state of CA to take on an intern or two for a summer project of processing the available data to create a layer useable by the emergency personnel of the state, in case of an emergency. There is much research yet to be done and it would be helpful if the carriers themselves could provide data on their sites. This data would help flesh out the database and correct any errors.

References
http://www.atttowers.com/towers/featuresServices.do

http://www.city-data.com/

http://wireless.fcc.gov/antenna/index.htm?job=home

http://www.atlas.ca.gov/