cell phone ping

There are two ways that celluar (cell) phones are located, depending on thecell phone itself, and the technology that is built in to that cell phone.Older cell phones are located via a process of signal triangulation, whilenewer phones have a Global Postitioning System (GPS) built in to them. Inpractice, one, the other or both can be used to locate a cell phone.Triangulation can be done on most any cell phone, depending on the locationof the cell phone and any nearby towers. GPS locating depends on the cellphone being so equipped. There is a federal mandate that pretty much allcell phone companies, including Verizon, will be able to locate a cell phonebased on one, the other or both methods.Here is more information on both processes.IT Digest - Ingenious Tejas's Digest Blog http://geekswithblogs.net/tpatel/archive/2004/06/29/7329.aspx"Cell phones are two way radio transmitters that work by connecting to anearby tower and exchanging data. Despite the FCC's limitation on maximumpower output of a cell phone, they are still able to connect with towersmiles away at UHF frequencies ... Because cell phones put out a constant RFoutput (sometimes pulsed) they can be tracked using the tower triangulationmethod where the network administrators can find your precise location withtheir administrative network access."The Graduate School and University Center at the City University of New York(CUNY) has "Intro to Mapping Sciences" taught by Doug Williamson. http://www.geography.hunter.cuny.edu/~dougwill/CRIME/the_district/web_site/ep19/ep19.htm"Phase II of the FCC regulations will begin to be implemented in the fall of2001. During Phase II, wireless carriers and the PSAPs will be upgradingtheir systems to provide more exact geographic coordinates. Two methods willbe employed:1) triangulation: new receivers will be added to the tower arrays that willbe able to perform triangulation; and 2) global positioning receivers (GPS)may be added to new wireless phones.""Cell-phone companies add tracking abilities" was a Knight Ridder distributedarticle, dated Wednesday, July 20, 2005, written for the Dallas Morning Newsby Terry Maxon, here presented on the Portsmouth Herald web site.http://www.seacoastonline.com/news/07212005/biz_nati/53872.htm"However, a federal mandate requiring cell phones to automatically tell 911centers where the caller is located has speeded adoption.That can be accomplished through ground-based triangulation, in which thephone's location is determined by figuring its relative distance from variouscell stations. But most large cellular companies appear to be embracing theGPS method....Nextel has had GPS technology in every phone since November 2002. Sprint andVerizon phones also contain GPS technology, allowing them to provide locatorservices if they desire."This last article is a great one to read, as it speaks to how the technologyhas commerical applications, such as allowing shuttle companies track theirvans and giving directions to people over their cell phones.Here are some Verizon links on the subject and related services they offer.Frequently Asked Questions - Answers to FAQs http://www.verizonwireless.com/b2c/dispatcher?action=DISPLAY&item=_FAQ_TOPIC&topicID=243"The GPS (Global Positioning System) locator chip, which is present in allwireless phones we currently sell, except the BlackBerry 6750, is used solelyfor tracking purposes by Emergency 911 Services and does not function like atypical GPS device....Phase II Enhanced 911 rules requires wireless carriers to automaticallyprovide the telephone number of the 911 caller and far more precise locationinformation, within 50 to 100 meters in most cases.The first two steps have been implemented, however the third step (Phase II)is still in progress."Small/Medium Business - Fleet Administratorhttp://www.verizonwireless.com/b2c/businessSolutions/smallMediumBusiness/custom.jsp"Locate, monitor and manage vehicles equipped with the necessary vehicletracking hardware from any office computer."The technical terms for these services are ones such as "cellular phone GPSlocating" and "cellular phone signal traingulation" and E991 locating.The requirements for this technology came from the Federal CommunicationsCommission (FCC) wireless "Enhanced 911" (E911) rules.http://www.fcc.gov/911/enhanced/"The wireless E911 program is divided into two parts - Phase I and Phase II.Phase I requires carriers, upon appropriate request by a local Public SafetyAnswering Point (PSAP), to report the telephone number of a wireless 911caller and the location of the antenna that received the call. Phase IIrequires wireless carriers to provide far more precise location information,within 50 to 300 meters in most cases."More information on Phase II from this Wireless Advisor forum.http://forums.wirelessadvisor.com/archive/index.php/t-2863.html"In the second phase, cell phone companies have two options for significantlyimproving the locating capacity. They can install GPS chips in theirtelephones. The chip determines the phone’s location (in hours, minutes, andseconds of longitude and latitude) by receiving signals beamed down from anarray of satellites. The chip determines the location based on differentarrival times of these signals. Alternatively, a cell phone company cancomply with the mandate by using information provided by its network. Thisapproach uses towers and antennae in the carrier's network to measure thetiming of signals emitted from the phone, and thus its location ..."