Frequently Asked Questions
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The following questions and answers have been obtained from emails I have received and questions that have been asked of me in person. These answers are to the best of my knowledge and by no means represent any definitive / absolute answer / solution to any problem. Every day we all learn more, and hopefully what we all know and learn can be shared here in regards to Wireless Towers and their Sites, as well as Carriers and their related technologies.
This FAQ is not for basic questions on wireless phone technology, it is related only to what this web site contains. If you want to find out information about wireless carriers, wireless service providers, the basics of cellular technology, or anything else, please visit the links page for additional help in finding your answers.
QUICK INDEX LINKS
Why does this website exist?
How do I find out if a certain carrier will provide service on a certain tower or in my town?
How do you know which antenna at a site is for which carrier?I want to use a photo from this website
Why are Google Ads appearing on this site?
My phone needs a better antenna for better reception
About WAP (WSP/WTP/WDP/HTTP over TCP/IP and W-HTTP)
Detuning Structures near AM Broadcast Towers
System Interworking (Handoff) Observations
A quick lesson in frequency allocations for NH and MA for the most prevalent providers
General concepts on the build out of wireless technology
How to decode s Sprint PCS site code identifier?
Field Test Mode with Cingular Wireless and the Nokia 5160
How do you know what you do about this technology?
Very simply, this information is in my head and not sharing it with the general public would be a shame. I have been an amateur radio (HAM) operator for a number of years and ever since I was a young boy, have always been into identifying radio transmittion towers of one kind or another. This website is a resource to share what I know. It is done STRICKLY AS A HOBBY. I have no interest in accellerating this hobby into something that takes more time out of my life today.
Why do Google Ads appear on this site?
Well, after over two years of paying for this site hosting and all of it's related expenses out of my own pocket, and not getting enough PayPal donations to cover the yearly costs of the site, instead of closing / folding the site completely, I decided to run some Google Ads on it.
I can honestly say that I am glad I made that decision, as I can now re-couperate the yealy costs assiciated with this site via those ads.
Better Antennas for your cell phone
I get alot of questions about cell phone performance, or lack thereof. I have found that having an external antenna connected to your cell phone will greatly increase your reception. Most people don't realize that the model of phone they use has ALOT to do with how they perceive the quality of their wireless service provider. Its not always the service provider's fault that you drop calls often or that you don't have any service in a specific area or even inside your house.
There are two approaches to improving your cell phone reception, both require you to purchase an external antenna for your phone. Most phones today provide an external antenna jack, and if they do not, then you can often times remove your existing antenna and replace it with an adapter that will plug into an external antenna.
If you want to use your phone with an external antenna while mobile (driving), then I would recommend a good magnet mount antenna. These are usually very small (8 inches or less in height) and will mount to the roof or trunk of your car. The best place for the antenna is in the middle of the roof , but your phone will work no matter where the antenna is as long as it's on the outside of the car.
Some sites to check out are http://antennaguy.com and http://wilsonelectronics.com and search for their magnet mount cell phone antennas. You can also use these antennas at home if you mount it outside an window, or even keep it near a window inside the house. A co-worker recently bought one for his Verizon T720 phone. Where he works inside the building, he has no service with his phone. He bought one of thse magnet mount antennas and now he has 3 bars of service inside the building. Pretty good gain if you asked me!
There are people who have zero or very sparse cell phone coverage from their homes and their want to be able to use their phones from home. The best bet for this is to buy a Yagi Cell Phone Antenna. It requires you to mount it high above the ground on a mast or chimney, and run a fair about of wire to it (make sure to ground it too). An adapter at the other end of the wire is still needed to adapt it to your phone model. These typically run above the $100 mark, but if it's imperative you get your phone to work at your remote location, then this is your only option. Search the internet for "Yagi Cell Antenna" and you should find a number of vendors offering products. I have no personal experience with any of these vendors, but I do have alot of experience with Yagi antennas that I have used for Amateur Radio use.
All photographic images on this website, as well as all associated text, is copyright by the webmaster. As it states on the front page of the site:
This web site and it's contents are copyright © by Michael Catalanotti
Any use of photography strictly prohibited without written permission of the author.
All photography is digitally signed and watermarked.In order for anyone to reprint, republish, or use the photos contained within this website, written permission is required. Non commercial use of photos is encouraged, but written permission must still be obtained. To obtain permission, simply send an email and ask. Please state what the purpose of using the photos will be.
Also note, photos submitted to this website will become property of this website and of the website author after the submitter has given said permission, in writing, to post the photo(s) and information. Credit for the photos will be stated where applicable, except in cases where the submitter's identification is asked to remain anonymous.
Please view this website's policies and procedures page for more information.
A quick lesson in frequency allocations for the regions most prevalent providers
Provider |
General Frequency Range |
Technology |
Verizon Wireless |
824 - 894MHz |
CDMA / EV-DO / AMPS |
U.S. Cellular |
824 - 894MHz |
CDMA / TDMA / AMPS |
Cingular |
824 - 894MHz |
GSM / EDGE / TDMA / AMPS |
Nextel |
860MHz |
ESMR |
Cingular (formerly AT&T) |
1800-1900MHz |
GSM / EDGE / TDMA |
Sprint PCS |
1800-1900MHz |
CDMA / EV-DO |
T-Mobile |
1900MHz |
GSM / EDGE |
Refer to the links page for more sites covering Frequencies and Technologies.
General concepts on the build out of wireless technology
As America get's plastered with as much wireless coverage and penetration as possible, with each passing day it becomes easier to guess which wireless provider is rolling out a new cell tower. Typically, some areas still don't have basic cellular service. No towers are anywhere. In these places, like it was for metropolitan regions back in the late 1980's and early 1990's, typically the cellular providers will roll out a site first. These are the ones that occupy the 800 and 900 Mhz frequency bands. (In NH and MA, this would be Verizon Wireless, Cingular, U.S. Cellular, and Nextel).
How do I find out if a certain carrier will provide service on a certain tower or in my town?
First off, go to the website of the wireless carrier or provider you are interested in and scour their website for coverage maps. Some carriers have maps down to the street level which can show you current and or planned service maps.
Here are a few. Remember, these maps may not be accurate and may not depict new towers nor new coverage and or service.AT&T Street Level Coverage Maps
Nice tool to zoon in baed on your zip code to identify coverage.
T-Mobile Street Level Coverage Maps
Nice tool to zoon in baed on your zip code to identify coverage.Sprint PCS and NEXTEL Street Level Coverage Maps
Nice tool to zoon in baed on your zip code to identify coverage.If the maps don't work, and your feeling a bit like an explorer, do some footwork. If you do any of these suggestions and find out any info, please let me know so I can post in on my website (and give you the credit!).
If the cell site is new and it is easily accessible, you can simple go by the site and watch for a cell site technician / company. While they are doing work at the site you can simply ask them about what carriers are there and are planned. Each provider will most likely hire different site technician, so they may not have any or all of the answers.Next in line is to monitor a town's Planning Board / Commission website for their minutes to see who has applied for a permit to build or co-locate on an existing cell site or structure. You can simply search the online minutes and look for key words such as "tower" or "antenna" as well as each carrier's name (like Cingular, Sprint, etc.). This is a really good way to find out information long before a tower is constructed or any antennas are installed. If you find some online data from a town website for a new cell site, please pass it along to me!!!!!!
List of All New Hampshire Municipal Websites
All of New Hampshire's municipal websites, sorted alphabetically by town name.If the town does not have it's minutes online, then he next step would be to simply go to the town offices and ask the planning commissioners if anyone else wireless carrier has asked to co-locate on the tower or has applied for a permit to install equipment.
Or you can simply watch the tower and see if any new atennas appear in time, then you will know someone else is co-locating.Got any other input to add here? Please let me know and I'll be happy to add it!
How do you know which antenna at a site is for which carrier?
General ways to find out:
Yagi Antennas (Verizon in this case) |
Traditional Flat Faced (T-Mobile) |
Omni directional |
Want to read how one of the flat faced panel type antennas needs to be installed by field engineers?
If so, click here for the MS Word document on how to install the Decibel Products PCS antenna.
How to decode s Sprint PCS site code identifier? (Thanks to PBW for this nice ditty!)
I noticed you had a picture of a Sprint PCS ID. In one of your pictures you have BS54XC891 or something similar. The first two letters are part of the BTA license name. We have two main id's here: RI and NO. RI is for Richmond-Petersburg and NO is for Norfolk-Newport News-Virginia Beach. Washington, D.C./Baltimore, MD are split between DC (urban sites) and WA (rural sites). I figure stuff in MD has there own codes but generally it is one code per license BTS. In your case BS is probably short for Boston.
The next two numbers are what I and others think is a build out code.
In my market and the Richmond one the original build out consisted of 03, so anything that reads RI03 is part of the initial rollout. The next rollout appears to be 33 which was mostly in rural areas. Other codes include 13, 20, 23, 25 and 54. Some markets have the same build out numbers others don't. For instance 13 is exclusive to the Richmond BTA only while 33 and 54 can be found in both Richmond and Norfolk BTS or Norfolk and DC (for 54). In your site ID example this is the 54 after the BS XC. No one knows, possibly a placeholder.
It seems that Sprint PCS assigns the site IDs a head of time. For example we had NO03XC501 for several years but Sprint finally built NO3XC502 two years ago or so, well into the 54 and 25 build outs.
The last three digits are unique to each site and are just a number as far as I can tell. They do not appear to be related to any site parameters I know of (PN offset or Base_IDs, etc.). Don't bother asking a Sprint PCS tech. I had one in a night class a year or two ago and we discussed this an the new MTSO at length and he admitted I seemed to know more about the IDs and area network than he did.
System Interworking Observations (How carriers do at handing off between each other)
Why does your call always drag or drop in the same general area in your travels between carriers?
(Thanks to Scott C. of Haverhill MA for this information with input from Mike as well intermingled)
Verizon has a problem going up route 125, at the Rockingham Strafford county line it will not handover the call to
Unicel which is the adjacent b carrier. No matter how many times you try it, and with what equipment, it will not do it. Verizon, however, will hand over to that same system if you drive up route 95. Revenue related? No, incompetence, yes. In amps mode, using a diamondtel 92 and external antenna we could drag the call up to the Spaulding Turnpike in Rochester, right past several candidates for handoff.Cingular is very good at handing calls over to ATT 501 and USCC 445 but neither carrier is particularly good at handing them back. There is so much co-channel interference on the 7/445 border, Rockingham/Hillsborough you'd think the two carriers never heard of each other. Going out route 111 the handover is fine going either way but on other roads, the error rate rises due to co-channel interference and the call eventually goes away.
The new ATT site north of UNH is the worst example of cellular radio engineering I have ever seen. That site threw a monkey wrench into a system that had been working quite well until that site went in. Who every set up the neighbor list and the parameters for handing off had no idea of what they were doing.
I generally have good luck going from Salem to Dracut, via Pelham, the call will be handed from system 7 to 445 back to 7 much of the time.In the old days, when there were fewer cells, it was fun to "dx" the system and see how much beyond the cgsa you could pick up the home system.
Mike says: As for all the other carriers, I cant start to speak for them. I know half the reason why I switched from US Cellular to Verizon was that I was sick and tired of US Cell not handing over to Cingular and vice-versa when I was roaming in Mass. I pulled my hair out with that one and their customer support people and eventually got a contact at the inside with a systems engineer who helped me get USCC working with many handoff zones and then only to find out that a few months later, someone changed something again and it stopped working. Also, their SMS delivery on Cingular was whacked and not reliable at all. All those headaches made me switch from USCC after years to Verizon (which I find to be alot more reliable plus for the same rate I was paying USCC.
Cingular does a fine job of handing calls to adjacent carriers, what the adjacent carrier does with the call is another story. I was doing some testing up on the Strafford/Rockingham county line and ATT is just as poor as ever. Lost several calls while on ATT due to co-channel interference. If they had just handed to call back to Cingular's Brentwood site, the best candidate, there would have been no problem.
USCC isn't much better along the Hillsborough/Rockingham county line. Cingular hands the call over properly, turn around and drive back into Cingular territory and USCC will typically drag the call until it is lost due to co-channel interference, adjacent channel interference, or simply loss of signal.
It appears to me that they don't know how to properly setup the neighbor lists and when to hand the calls over.
They seem to have route 111 down though, I have taken calls from cingular to uscc, back to cingular in Pepperell, then back to uscc in nashua and then back to Cingular in Windham.
There are some places where Cingular won't hand over to the adjacent carrier and I find that quite annoying although I have yet to find a place as blatant as route 125. Verizon needs to get on the ball and get that problem fixed. As for reasons of revenue, none of the areas I am talking about could come under that category because they already hand calls over to the carrier in other places.
(The discussion of revenue was raised prior to this that many times it's more convenient for the wireless carrier to simply drop the call and force you to re-make the call based on charge rate areas. This was perhaps more true when long distance really was long distance. Now it's more of an issue of engineering and setting up adjacent neighbor lists correctly).
My experience with handovers is that the Windham site hands ok to Hudson USCC and vice versa OK. The (Derry) Wilson site hands to USCC but they have a hard time giving calls back. Poor uscc engineering. No handover going up 27 into Merrimack County from Rockingham last time I tried. Brentwood hands to Durham or Barrington going up 125 without difficulty. Once ATT gets the ball, there is a good chance that their system will drop it. Going up route 108 Brentwood and Greenland hand over to Durham and Dover without difficulty, ATT tends to drop the ball and doesn't like to give it back to Cingular.
Going up route 156 towards Snottingham you are climbing, co-channel interference becomes and issue. At the top of the hill you get both Cingular and ATT and of course it is too much to ask that they co-ordinate their channel use. If your phone does not support home only or if you don't forbid ATT, once you get up in that area you get ATT and Cingular alternating. Poor engineering on both Cingular and ATT's part, although ATT is the bigger problem with their defective Durham site. Sloppy, very sloppy.
Verizon was and probably still is good at handing calls from it's 28 to 428 system and vice versa. In fact, one of the interesting things about cdma is that you are notified of a handoff when it happens, with tdma and analog you need to be familiar with who is using what channels in the area to be absolutely sure that you've handed over to the other system or know a few tricks to find out.
There was a place on route 121 in Atkinson, just south of the Hampstead border where you picked up a cell from system 428 and in cdma mode the phone would notify you for a few seconds that you were "roaming." I took an analog phone up there, set it to system 428 in home only and sure enough I could setup calls on the other system.
In the last 3 years there were a couple of times where system 28 was off. That's the Boston/Rockingham County Verizon system. All of the cells were totally off for an hour or so. It was interesting because I jumped in the car and with the 3 watt amp and external antenna I was able to make calls from much of Rockingham County from the 428 system. Other places I got system 484 which is Star/Unicel/Rcc. I had better luck in Amps mode than in cdma mode.
You can call *1, smart traveler from an inactive phone on Verizon and hold the call while traveling across systems.
Cingular Handoff's to adjacent carrier summary...
Route 111 to USCC .. .. Excellent, no problems. Windham to Hudson
Route 38 to USCC Mediocre, sometimes yes, sometimes no. Salem to Pelham Route 38 to USCC
Cingular to USCC route 111 Windham to Pelham Excellent, Very reliable.
Cingular to USCC route 38 Salem to Pelham poor, sometimes it works, sometimes it doesn't. With an external antenna and phone set to home only you can keep system 7 service on most of 38.
Cingular to USCC route 38 Dracut to Pelham poor sometimes yes, sometimes no.
Cingular to USCC Londonderry to Manchester good, most of the time it hands over.
Cingular to USCC Candia to Merrimack County, no good going out route 27 or through Bear Brook state park.Cingular to ATT route 125 Rockingham/Strafford Excellent but ATT usually will drop the ball after the handover due to poor engineering on their part.
Cingular to ATT route 108 Rockingham/Strafford .. same as above.
Cingular to ATT route 95 Portsmouth/Dover point.. Excellent always hands over and the call can usually be held up to about Union on route 125.
Verizon notes...
Handovers from system 28 to 428 worked fine in all areas tried.
Will NOT hand over going up route 125, you will lose your call near route 152 in Lee.
Handovers going up route 95 to Unicel on the Rockingham / Strafford county line were fine.
Field Test Mode with Cingular Wireless and my Nokia 5160 (Thanks to Scott C. for this info!)
ATT has been very easy to track because the phone only indicates maximum reading when you are right on top of the site and sometimes not even then. With your 5160 in test mode screen one you will see the signal strength as a negative number. When you get down into the -50s you are right on top of it, -51 is the maximum reading. At that point you need to be looking at the boresite to get a reading like that.
The display will also show a channel number, this is the setup channel, as you drive around a site, the signal strength will decrease and then the phone will rescan, lock into the proper setup channel for that face of the cell and the signal strength will increase to near max, this will continue as you drive around the site. There should be three channels for each site. I watch the signal indicator and once I start getting readings consistently in the -60s and -50s I start looking for the antenna. When I get down to -51 I know I'm on top of it and it is just a matter of looking for it.
How do you know what you do about this technology?
I have been an amateur radio enthusiast (ham radio operator) since about 1980, learning all I can about Radio Frequency and related technologies. My first full "ham shack" was constructed in 1996 and configured to use the AMSAT series of repeaters located onboard satellites orbiting the earth. I worked those birds for a few years and then became blessed with raising two awesome children, so the ham gear and shack sit idle until some future day in time.
I have also been closely watching the build out of Cellular providers since the mid-1980's and then watching the slow but sure deployment by the PCS carriers since the early to mid 1990's. I also have worked for a few years in the field of wireless phone systems writing embedded code for a TDOA (Time Difference of Arrival) system used for triangulation of RF signals to locate wireless subscribers to within 30 feet of their actual location. This system is deployed today and works as a co-lo installation with exiting cellular sites (for all technologies, TDMA, CDMA, GSM, etc.). This system was created back in 1994 to look forward and eventually comply with the E911 (Enhanced 911) capabilities required by the FCC.
I'm currently employed by Siemens Networks, LLC., soon to merge into Nokia Siemens Networks, which manufactures voice offload switches utilizing many of the technologies used in the wireless industries, specifically IMS. Wireless carriers (as well as RBOCs and CLECs) use our switches to help perform their VoP (Voice over Packet) rollout, and of course the return on investment and cost savings that goes along with such services. I have been employed by Siemens now for 9 years. Prior employment includes Prime Computer, Framingham Mass, and Cabletron Systems, Inc. Rochester/Merrimack/Nashua New Hampshire.
Looking for a job in this field? If you have some experience and a resume, please drop me a note and let me know. We always have positions opened that need to be filled!
The Detuning of Vertical Structures near AM Broadcast Antenna Systems
Thanks to Jack Layton CPBE for this information.
When any metallic structure is constructed near an AM broadcast station's antenna system there exists the possibility of it distorting the station's licensed radiation pattern. The entire tower structure is the radiating element for an AM broadcast station. The most common arrangement used by AM stations is called a series fed antenna. The tower sits on a base insulator and RF energy is fed from the transmitter to the base of the tower via a coaxial transmission line. A network consisting of inductors and capacitors forms the matching interface between the coaxial line and the radiating element. RF energy is fed between the tower base and the ground system which consists, minimally, of 120 buried radial wires.
AM broadcast stations use one of two types of antennas: A single tower is called a non-directional antenna. The radiation pattern produced by a non-directional antenna is circular - that is an equal amount of signal is radiated at all azimuths. A directional antenna system utilizes two or more towers and ground systems as described above. Directional antenna systems with as many as twelve towers are in use at AM broadcast station in the United States. These systems produce a radiation pattern that delivers a different amount of signal at each azimuth. These systems are used to deliver maximum signal over populated areas and minimum amounts of signal toward other stations on the same or adjacent frequencies. Some stations utilize different radiation patterns for day and night operation.
In a directional antenna system each radiating element is driven through its own coaxial feed line with RF energy from the station's transmitter. The interface between the transmitter and each feed line is a piece of equipment called a phasor. The phasor provides for control of the magnitude (amount) of RF current fed to each element and the phase (timing) of the RF current fed to each element in the system. This allows for precise control of the shape of the radiation pattern produced by the directional antenna system.
The FCC license issued for operation of a directional antenna system specifies the phase of the RF current in each element as well as the ratio of the RF current in each element. FCC rules require that these operating parameters be maintained within close tolerance of those specified in the station license. In addition, the license for a directional antenna system will specify monitor points. These points are described in great detail in the station license. One is assigned on each protected azimuth. The license will list maximum values of field intensity permitted at each of these points. Periodic field strength measurements made at the monitor points are used to provide a quick field check on the operation of the system.
When a metallic structure with a height of an eighth wave length or more (45 electrical degrees or more) is constructed near an AM antenna system there exists the possibility that energy picked up and reradiated by this structure can distort the licensed circular or directional radiation pattern. The structure need not be a radio tower. Water tanks, light standards and high voltage transmission line support towers can reradiate AM energy. FCC rules require that anyone proposing to construct such a structure within a half mile of a non-directional AM antenna or within 2 miles of a directional antenna system take certain precautions to preclude disruption to the AM radiation pattern. Normally a study is made to assess the possibility and probability of distortion to the licensed pattern. If it appears that a problem will be created a detuning apparatus is installed on the structure. In addition field intensity measurements are made before construction takes place and then repeated in the same places after construction (or modification to an existing structure) has been completed. The individual measured field intensities are compared to assess what - if any - effect the new structure has had on the radiation pattern.
A typical detuning apparatus consists of three wires dropped down the structure from a point near the top of it or from a height near the quarter wave length point. This is called a skirt. The wires are electrically connected to the tower at the top and spaced 18 to 36 inches off each face on insulators. At a point near the bottom a wire ring ties the three wires together and connects to a detuning network. The network can be as simple as a variable capacitor connected between the lead from the ring to ground. The skirt and capacitor form a one turn tuned circuit at the AM frequency. This brings the induced RF current in the structure to a minimum. Re-radiation and current are synonymous therefore under this condition re-radiation is at a minimum.
One simple method of instrumentation used to indicate minimum re-radiation is the field intensity meter. It has a very directional loop antenna mounted in the lid of the instrument. It is set up on a tripod pointed toward the reradiating structure and at a right angle to the on coming wave front from the radio station. When the skirt is tuned to resonance the field intensity meter will drop to a value of -30 or -40 db of its previous value. Typically, a monopole or uniform cross section guyed tower (with insulators breaking up the guy wires) will detune to -40 db or better. A self supporting tapered tower will typically detune to -25 to -30 db of its untuned value.
Cingular Wireless TDMA and GSM Modes
By the way, this set of information os presented in an unbiased fashion. I am not trying to push Cingular's service, I'm just trying to present some factual information.
For those who still think that Cingular's wireless coverage is poor, it's time to get familiar with their new phones and the newest mode they operate in. I have family members who have had expired Cingular contracts for a while and they keep complaining about how poor Cingular's coverage is. The fact is, Cingular is pretty much DONE with their TDMA network rollouts and offerings. All new buildout's today are done with using their GSM solution. All you need to do as an Cingular Wireless customer is go to their store and buy a new phone that does both TDMA and GSM and you're all set. You'll have far better coverage with your phone nationwide. All of the old phones are TDMA only mode, and that severely limits your wireless coverage. You may have to renew your contract, but hey - it's worth it if you want to stay with Cingular.
If my family members were to get new phones, they would now have tons more coverage in towns in NH and MA that do not have Cingular TDMA coverage but now do have their GSM service.
WAP Protocol Quick Technical Tutorial
If you look at WAP 2.0, there are essentially two layers of it. Relating it to the OSI model, the top layer is the presentation layer. This is the markup language that is used for presentation in the browser.
In order to be WAP 2.0 compliant, a browser needs to support XHTML Basic (and there is a variant known as XHTML Mobile Profile). A WAP 2.0 device will also usually support WML for compatibility with existing WAP services, although this is not required by the specifications. (This backward compatibility is however, a market requirement, outside of Japan.)
The next layer is the transport layer. This is how the browser communicates.
A WAP 2.0 compliant device can support either the existing WAP protocols (WSP/WTP/WDP), or it can directly implement HTTP over TCP/IP. When it implements HTTP over TCP/IP, it is supposed to use Wireless Profiled HTTP (W-HTTP) and Wireless Profiled TCP (W-TCP), which are basically some interoperable with regular HTTP and TCP/IP, which involve some configuration options for optimization in wireless environments.
There are a number of WAP 2.0 devices on the market that implement WAP 2.0 over the existing WAP protocols, each may implement them differently.
Why would you want to use a proxy? Well, it can generally offer better performance by reducing some of the extra activity related to DNS queries, and it can generally optimise the wireless connection by supporting compression and keep-alive sockets.
There is also an issue on many networks that the WAP gateway is integrated with RADIUS to identify the MSISDN of connected users. This is particularly important for MMS, where the WAP gateway often supplies the MSISDN in an HTTP header, so that the MMSC can identify the user that is making a request.
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