Living close to cellphone tower - Page 1
Forum section: electronics / general

author: dogbox
author_rank: Contributor
timestamp: February 01, 2016, 01:17:04 am
content: Hi, just wondering if anyone has real knowledge on the risks/potential risk of living in close proximity to cell tower. When I say close, I mean right next door-less than 20m from where you would be sleeping on the top floor. I'm in the process of house hunting a rental here in Sumatra. The laws about where they place these things seems pretty different (non-existent) to Australia. This property is advertised way under market value. I'd say their struggling to find tenants and have dropped the price, this tower seems close even for here. There's a lot of hype and mis-information on the web. Hoping someone here knows about this subject or could point me in the direction of a refererence.

author: uncle_bob
author_rank: Unknown
timestamp: February 01, 2016, 01:40:26 am
content: HiThe antennas on a cell tower normally shoot the signals out (horizontal) and down a bit (say 10 to 20 degrees). The *best* place to be is directly under the tower. At least by design very little RF goes straight down. The worst case is being able to look out your window and see the antennas on the same level as you are on.Beyond the biological issues (which are no well understood) there are the more practical issues. The RF from the tower is likely to overload various gizmos you might try to use. A lot depends on the exact bands the tower is running. Not being able to run WiFi is a bit of a pain. Not being able to watch TV is a bit bigger pain. Having your PC speakers emit odd chirps every few hours can be fun for the first day or two. After that ... not so much fun.My guess is that they have people move in. None of their electronics work reliably and the people move out. They drop the price and try again. Same problem and they drop it again. Eventually they will find somebody with no electronic gear and they will have a customer.Bob

author: Brumby
author_rank: Unknown
timestamp: February 01, 2016, 01:42:51 am
content: There is a thread that explored this general area not long ago here. Might be worth a read.https://www.eevblog.com/forum/chat/harmful-radio-waves-suddenly-no-one-talk-about-it/

author: _Andrew_
author_rank: Regular Contributor
timestamp: February 01, 2016, 01:59:33 am
content: You could take a look at these documentshttps://www.fcc.gov/cgb/consumerfacts/rfexposure.pdfhttp://www.ct.gov/dph/lib/dph/environmental_health/eoha/pdf/051115_cell_phone_tower_final.pdfThe antennas on the tower will have a polar paten and could be crudely described as emits from that antennas in a wedged shaped beam >I< across the horizon. So there is an area close beneath the tower where the signal is often not actually directed.Imagen standing at the bottom of a lighthouse next to the tower looking strait up you can see there is light coming out projected to the horizon but you can not directly observe the bright lamp because the actual structure of the lighthouse prevents you from seeing it. Next you walk away from the lighthouse until you are stood where you can directly observe the lamp and get the bright flash of the light in your eyes. So the aria under the lighthouse where you can not directly observe the bright flash it the area of shade under the lighthouse and receives less of the light. A similar thing happens with antenna towers where less signal gets to the area in shade under the tower because the signal is being directed out to the horizon. At the moment everybody seems to be excepting that at the distance the beam paten intersects where there is human occupation the over all energy has dissipated to a safe level. Unfortunately there does not seem to be presently any evidence that suggests anything other than the current guidelines.Personalty I would not live directly in line, in close proximity with the antenna on a mobile phone tower.Which is odd as I have a tower on top of my workshop with 4 microwave links and a UHF transmitter antenna presently on it.

author: dogbox
author_rank: Contributor
timestamp: February 01, 2016, 02:28:34 am
content: Quote from: uncle_bob on February 01, 2016, 01:40:26 amYThanks for the quick reply..ep I have yet to contact the owners..just went around and took some pics. The RF interference will be a pain, and I'd say that they have had tenants move out as you say uncle Bob. I guess to prove the point I could arrange a viewing and take a laptop and set of powered speakers. Is there some kind quick and dirty rf meter circuit..i have limited access to buying parts..but have in stock a bunch of opamps many values of transistors, caps, resistors, leds, buzzers etc..stuff you use for guitar amps and effects pedals. thinking maybe I could breadboard something to take around..if starts wailing then that would a test. Any suggestions???

author: dogbox
author_rank: Contributor
timestamp: February 01, 2016, 02:37:39 am
content: main bedroom appears to be top floor on the left side (unseen), as there is an air conditioner installed.

author: dogbox
author_rank: Contributor
timestamp: February 01, 2016, 02:39:56 am
content: It don't get much closer than this..

author: dogbox
author_rank: Contributor
timestamp: February 01, 2016, 03:01:29 am
content: Quote from: _Andrew_ on February 01, 2016, 01:59:33 amThanks Andrew, I will read the info on links you provided. Have attached some pics..would you run a mile from this place, or would this be in the shadow??? I think its a case of it seems to good to be true. They have listed this slightly above of what you would normally pay for a place half the size. An absolute bargain at approx $2700 AUD for the whole yearyes you pay rent in advance in Indonesia when you lease property, and its generally about 1/8-1/10 the price in Australia and other western countries. But if it means we are battling RFI and risking our health..then its a turkey.

author: vk6zgo
author_rank: Super Contributor
timestamp: February 01, 2016, 03:17:47 am
content: It looks a lot more like a general purpose Communications tower,rather than a cell tower.The tower itself does not radiate,it is simply there to elevate the antennas.All the microwave dishes are well above your bedroom,& in any case radiate directly out of the front of the dish------ any radiation in your direction would be wasted power,which Engineers don't like to see.Many thousands of people have spent their whole working life in similar proximity to such a tower with no ill effects.

author: dogbox
author_rank: Contributor
timestamp: February 01, 2016, 03:28:07 am
content: Quote from: vk6zgo on February 01, 2016, 03:17:47 amOK thanks for that vk6zgo. What about the possible issue of RFI ?? Could a general purpose comms tower still mess with appliances/tv/computers etc???

author: Brumby
author_rank: Unknown
timestamp: February 01, 2016, 03:43:00 am
content: I was curious if the roof is lined with Sisalation? (or something similar).... and a question to anyone: Does Sisalation offer any benefit in this situation?

author: vk6zgo
author_rank: Super Contributor
timestamp: February 01, 2016, 04:12:06 am
content: Quote from: dogbox on February 01, 2016, 03:28:07 amMaybe---there are a lot of RF sources up there,so even with tiny amounts of leakage,you may get mixing products,etc.The directionality of the dishes will minimise this possibility.If the cops,or some other Emergency service have omnidirectional antennas on low or high band VHF tacked onto the tower youcouldget image interference on TV or FM .I very much doubt that Wifi would be effected by anything on that tower.Effects upon non-RF appliances areveryunlikely---these are more common around high powered MF or HF antennas.One thing which may be a problem is reflections off the mast structure itself,which may cause ghosting with analogue TV,& odd effects with digital TV.You will be well protected from lightning strikes,though!

author: dogbox
author_rank: Contributor
timestamp: February 01, 2016, 04:58:43 am
content: Quote from: vk6zgo on February 01, 2016, 04:12:06 amOK so I haven'tcompletelywritten this one off the list yet ..still hanging in by a tiny thread:). TV (analogue still here) we can definitely live without..bad Indonesian soap operas-pretty much all thats played on the 3 fuzzy channels that can be picked up. Internet is critical...thats a deal breaker. I'd hate to move in only to find out that wi-fi not working poperly. Would bluetooth be effected similar to wifi..maybe I can test with a couple of paired devices??? There is a slight possibility that Telkom could send a technician around to test wi-fi. Love to be 100 percent sure..Also here's areallydumb question..Would close proximity to a gen. propose comms tower have an adverse effect on cellphone signal???

author: Richard Crowley
author_rank: Super Contributor
timestamp: February 01, 2016, 05:09:11 am
content: The only problem I would anticipate from such an antenna close to my living quarters is the visual "pollution" for people who don't like the look of it.It is extraordinarily unlikely that there will be ANY kind of interference or ill effects that you could detect. IMHO there is no health or RF interference concerns with a properly operating communication antenna site like this.Wouldn't it be easy enough to knock on a few doors in the neighborhood and ask people who live there if they are having any RFI problems? Nobody would know better than people who already live there. Much more reliable than any amount of expert speculation here.Remember that the amount of radiation you get from holding your cell phone against your head is orders of magnitude more than you will ever get from a cell tower, unless you climb up the tower to the antennas and stay for the afternoon. Look up the "inverse-square law".https://en.wikipedia.org/wiki/Inverse-square_law

author: ez24
author_rank: Super Contributor
timestamp: February 01, 2016, 06:26:04 am
content: Quote from: blueskull on February 01, 2016, 01:47:38 amYes the government is ALWAYS right !!

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: February 01, 2016, 07:15:16 am
content: Quote from: dogbox on February 01, 2016, 02:39:56 amThat does not look like cell phone base station tower - all I see is relay antennas (small parabolic dishes). Those should be very directional and radiation from them is minimal directly beneath the antenna.

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: February 01, 2016, 07:52:58 am
content: Quote from: dogbox on February 01, 2016, 01:17:04 amAll you really need to sleep well is to be able to measure it accurately and objectively. You will need1. Antenna. Large Log-periodic or Bi-conical antenna. It need to be large to cover 600MHz and sometimes 450MHz up to 3GHz.2. Spectrum analyzer that covers your area's LTE frequencies etc.I am not sure where you can rent this kind of equipment in Indonesia. Suitable antenna can be from $1500 to $3000, Spectrum analyzer - $5000 to $10000 used. Renting may cost about $150 to $300 here for few days. Is it available in your area? getting someone to come and test probably same?So I guess if you are paranoid - it costs you to deal with your paranoia as any other conditionbut granted paranoia is not always unfounded.

author: Theboel
author_rank: Frequent Contributor
timestamp: February 01, 2016, 08:04:01 am
content: I really sure its an cell phone tower with a lot of microwave link. Its typical eapecially in sumatra with very little fiber optic conection

author: matseng
author_rank: Frequent Contributor
timestamp: February 01, 2016, 08:12:05 am
content: Two typical cell phone antennas can be seen on the right hand side of the tower, just above the lamp post. Are there any more of them pointed in the direction of the house? The microwave links are highly directional by design and should not be a problem.

author: vk6zgo
author_rank: Super Contributor
timestamp: February 01, 2016, 08:25:06 am
content: Quote from: Alexei.Polkhanov on February 01, 2016, 07:15:16 amI don't think those dishes are all that small---they are still at a fair height.

author: KJDS
author_rank: Super Contributor
timestamp: February 01, 2016, 08:33:42 am
content: A GSM basestation antenna radiation meet the ICNIRP limits at about 1.5m from it. I'd prefer not to live anywhere with radiation within 10dB of those limits, which is met at about 4m from the face of the antenna.Unless you want to spend a lot of time sunbathing on the roof, or have an amazing ability on a trampoline I can't see you getting close enough for it to be a problem.

author: Srbel
author_rank: Frequent Contributor
timestamp: February 01, 2016, 08:57:01 am
content: It is not true that cell phone antennas don't radiate vertically. In theory, they don't, but in reality they do. With less power compared to horizontal, but still not insignificant!

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: February 01, 2016, 08:57:42 am
content: I found all towers around building where I live. There is probably a map like this for Indonesia. Find it - then we can calculate what is the expected RF power at your place.I just noticed that when we talk about power of base station antennas we are forgetting that some channels have 20 MHz bandwidth some 5, some 10. Plus as you may notice there are 5 antennas around my house for example - all belong to different networks. According to the azimuth some of their antenna have overlapping coverage on different frequencies.So... hot spots may not be where you would thing they are!

author: dogbox
author_rank: Contributor
timestamp: February 01, 2016, 12:20:31 pm
content: Quote from: Theboel on February 01, 2016, 08:04:01 amActually I'm on fibre optic at my current residence which is located about maybe 1km from the place we are discussing. Telkom have been doing a roll out for past 12 months, And yes this typically what most of the towers look like around here. Location is Bengkulu (KotaBengkulu or in english Bengkulu city), in the province of Bengkulu, Sumatra. The street in question is Jl. Kepuas V

author: Theboel
author_rank: Frequent Contributor
timestamp: February 01, 2016, 01:12:46 pm
content: Now that make sense thats tower must be use as end link to FO connection thats why its carry many microwave link. I have no expertise about health issue for this kind of situation.I just talk from my no science experience I worked with high power transmitter with 1 to 250kw transmitter but nothing so far health issue connected to my work.btw nice city with a fine beach but no surfing

author: cdev
author_rank: Super Contributor
timestamp: February 01, 2016, 01:17:15 pm
content: I am assuming that the top of that tower contains huge TV and radio broadcasting antennas for the entire area, if so, be aware that sometimes they do cause all sorts of strange effects especially when its foggy.Example- fluorescent lights blinking - when they are not on.

author: Richard Crowley
author_rank: Super Contributor
timestamp: February 01, 2016, 01:26:45 pm
content: There are certainly some cell antennas shown in the photo (the vertical rectangular boxes).But most of those are round microwave dishes. This is clearly a major communication hub of some kind.Both cell antennas and microwave dishes have very little RF radiation immediately below the antenna.(Or above the antenna, for that matter.) Directing power above or below the antenna is quite wasteful.The antennas have been designed for horizontal radiation for efficiency and coverage reasons.The tower is much bigger than would be warranted by a bunch of smallish round microwave dishes.There must be something higher up that would require a tower of that size.There also appears to be rather a large bundle of cables and waveguides feeding antennas above the photo.Is this also a broadcast TV and/or FM transmitting site?

author: vk6zgo
author_rank: Super Contributor
timestamp: February 01, 2016, 02:03:39 pm
content: Quote from: Richard Crowley on February 01, 2016, 01:26:45 pmIt is a reasonable sized tower,but I've seen plenty of that size in Oz with only microwave antennas on them.Thereisa somewhat larger dish further up.

author: dogbox
author_rank: Contributor
timestamp: February 01, 2016, 02:58:22 pm
content: Quote from: Theboel on February 01, 2016, 01:12:46 pmNo surfing..wanna betshhh its our little secret...

author: Syntax_Error
author_rank: Regular Contributor
timestamp: February 01, 2016, 08:54:57 pm
content: The only thing I would look out for is if you see one or more of those microwave dishes damaged or dipping down so they point directly at you. Other than that, I wouldn't worry about it.

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: February 01, 2016, 08:56:38 pm
content: I just noticed one thing looking at the info which says34.7 dbWin a screenshot I posted. So 37.4 dbW is converted to Watts:Pw = 1 * 10 ^(PdbW / 10) = 1 * 10^(34.7/10) = 2951.2 WThat is 3 kilowatts!!! Per sector!or 64.7 dBmIs that real? No wonder some people concerned.

author: Richard Crowley
author_rank: Super Contributor
timestamp: February 01, 2016, 09:39:35 pm
content: 3 KW per sector seems reasonable to me. Remember that it is not blasting 3 KW continuously.And remember that it is carefully directed horizontally away from the antenna and has very little power around the immediate area of the tower.How do we think cell phone coverage at GHz frequencies can reliably work with receiving antennas measured in mm, and buried in a ladies handbag inside a car?Or in the back pocket under a 300 pound = 130kg = 21.5 stone steelworker sitting in a bus.The only people who are "concerned" are those who don't understand the physics (and the biology).3 KW is orders of magnitude less than most AM/LW, FM, TV broadcast transmitters which DO operate continuously.For ~50 years now, and with no documented harm that would cause actual "concern".

author: Gyro
author_rank: Super Contributor
timestamp: February 01, 2016, 09:57:24 pm
content: One thing's for sure, the house isn't going to be at risk from direct lightning strikes!On the other hand, I'm not sure about the possible effects of INDIRECT ones... just a thought. I'm guessing here that thunderstorms are fairly common in Sumatra.

author: KJDS
author_rank: Super Contributor
timestamp: February 01, 2016, 10:45:02 pm
content: Quote from: Alexei.Polkhanov on February 01, 2016, 08:56:38 pmThat's not real for any cell system I've ever encountered.

author: uncle_bob
author_rank: Unknown
timestamp: February 02, 2016, 12:18:15 am
content: Quote from: Gyro on February 01, 2016, 09:57:24 pmHiIf you have ever spent time working on a tower based system .... Lightning strikes (often) ... current flows (lots of it) .... current spike is induced in anything nearby .... magnetic pulse does odd things to stuff nearby. Now hat CRT's are a lot less common, the magnetic part of that may not be quite as big a deal.-----In terms of testing things, the problem is often intermodulation. Signal A and Signal B and Signal C all come on at the same time and you get some weird combination of them and their harmonics. That drops into your gizmo and you get a chirp. Of course once you figure out what frequency causes the chirp you could do something about it. There are better ways to spend your time ...In all likelihood, you are in an RF dead zone right at the base of the tower. None of the stuff in the picture is putting out much power. Cell phones run on batteries. They need the same power to talk back to tower that the tower needs to talk to them (actually not quite true, the tower has a much better antenna). Net result is that, even handling a lot of calls, a tower does not put out massive amounts of power..Looks like a nice house. If I rented it, I'd make sure I could put one of *my* antennas up on the tower ....Bob

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: February 02, 2016, 12:52:43 am
content: Quote from: KJDS on February 01, 2016, 10:45:02 pmQuote from UK-based site (http://www.powerwatch.org.uk/science/faq.asp):"The area a macrocell is intended to cover is very variable, from at least 500 metres up to a maximum of about 35 km dependent upon capacity and clutter. The powers above need multiplying by the maximum number of active carriers and by the forward gain of the antennas, resulting in EIRPsbetween about 50 watts (17 dBW) and 1000 watts (30 dBW) per carrier frequency. Base stations typically have 4 carriers, but may have up to 16."So, I am not sure if Cell Map has listed power at the output of PA or EIRP. But given max 1000 Watts per carrier frequency and given that 3 frequencies used (Usual here in North America 850MHz, 1900MHZ and 2600 MHz) it does in fact match 34.7dbW or ~2.9kWHere is the map with all towers you can explore yourself:http://www.ertyu.org/steven_nikkel/cancellsites.html

author: vk6zgo
author_rank: Super Contributor
timestamp: February 02, 2016, 02:53:19 am
content: Quote from: Alexei.Polkhanov on February 02, 2016, 12:52:43 amIt is very unlikely that your Cell Map refers to power at the output of the PA--"real watts".Using very large power outputs in one spot is contrary to the whole concept of Cellphones.If you are having trouble getting sufficient coverage with your existing setup,just stick up another phone tower in the difficult area.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 02, 2016, 03:02:58 am
content: While the argument about the electrical danger of this tower will go on for decades, there is no question that you have a higher risk of the tower falling on you than someone who is further away. The tower might fall due to high winds, earthquake, corrosion, fatigue or collision by either ground traffic or a low flying aerial vehicle. In my personal opinion that risk is very small, but still larger than the electrical risk.

author: vk6zgo
author_rank: Super Contributor
timestamp: February 02, 2016, 03:16:56 am
content: Quote from: uncle_bob on February 02, 2016, 12:18:15 amOnly most of my working life.I can remember only a few such problem,One was at a Transmitter site,when,due to a rack's earthing not being properly linked to that of the Tower,the the burglar alarm & the input transistors on some Video Amplifiers got cooked.On another occasion,a video switcher on the Studio outside CCTV failed following a storm.Maybe a strike on the Telstra microwave tower which was reasonably close to the car park camera,or maybe not!Years before that,in Kalgoorlie,we had reed relays on an alarm interface to the phone lines.These kept welding themselves together,apparently due to thunderstorm activity.They were replaced with normal relays---no more trouble.

author: cdev
author_rank: Super Contributor
timestamp: February 02, 2016, 06:59:53 am
content: In San Francisco, in the Clarendon area right underneath Sutro Tower, (the huge TV tower that looms over SF) when it gets foggy, like it does quite frequently in the summer, florescent lights around there will sometimes flicker and glow without needing to be turned on.Yes, it does sometimes make electrical equipment go nuts.

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: February 02, 2016, 07:59:33 am
content: I know nothing about biology. My degree is in physics so I don't know anything about effects of RF on health. If I worried I probably had a stash of equipment to measure it, fact that I don't have good measurement equipment speaks for itselfStill I am very curious to calculate how much exactly of RF power from that specific tower reaches my apartment for example. In nW/cm2?In my case distance from tower to the antenna that I used in this test is 119 meters. No direct path unfortunately. Azimuth shown on Google Earth matches the azimuth of last 2600 MHz segment from that tower as shown on cell tower map. I think this is the one because frequency and bandwidth (20 mb) match.If I calculate the ideal free space loss of power for 119 m and 2600 MHz:FreeSpaceLoss = 36.56 + 20 log10(f) + 20 log10(d) = -82.23 dB.This Vivaldi antenna has gain of about 6 dBi at 2.6 GHz (9 dBi at 3.5up).So how do I accurately estimate the power of that transmitting antenna? I assume that it is 60 or 120 deg segment, most likely 60.Now in terms of power density if it was really 1 kW outPd = (Pt * Gt) / (4 * Pi * R^2) or in metersPd = (1000 * 10) / (4 * Pi * 119^2) = 0.056W/m2 or 0.0056 mW /cm2 or 5uW/cm2.European Parliament recommendation is 10 nW/cm2 so if it was true 1kW it would be waaaaay out of norm according to EU but in US 579,000 nW/cm2 is a norm.Also I have to say that two things that someone mentioned here - base station only transmits periodically. True, but only for channels that used to voice. This 20Mb channel - is continuous, always on data stream. All GSM stations have broadcast channel (strongest) and control channel(s) and these are always on.Not all buildings allow base stations so cell companies ended up installing base stations on lower building - see elevation of that base station is 14 meters. My apartment is 68 meters above ground level. It means that apartments on floors 5-7 exposed directly to the signal if transmitting antenna is pointed horizontally.

author: 1xrtt
author_rank: Regular Contributor
timestamp: February 02, 2016, 11:50:57 am
content: I'm just guessing, but with the tower this close, is there a container at the base of it, with a very loud air conditioner blowing hot air in the direction of the house?

author: dannyf
author_rank: Super Contributor
timestamp: February 02, 2016, 11:57:08 am
content: It probably represents a bigger risk to your bank accounts than hour health, assuming that you own it.

author: KJDS
author_rank: Super Contributor
timestamp: February 02, 2016, 03:18:55 pm
content: Quote from: Alexei.Polkhanov on February 02, 2016, 12:52:43 amIf I put 10W from a transmitter into a 40dBi antenna, that doesn't mean if you stand in front of it you'd absorb 50dBW. You might, if standing very close in the worst possible place absorb 10W, but you can't absorb any more than that because that's all that is going in. Cell basestation transmitters typically run at no more than 40W average, and there are 4 combined, but the combining means that only 10W from each carrier gets to the antenna.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 02, 2016, 05:04:30 pm
content: Quote from: Alexei.Polkhanov on February 01, 2016, 08:56:38 pmI know that the backup batteries they put in these things for power outages wouldn't support 3Kw for more than a few seconds, so there is something fishy in the numbers.

author: uncle_bob
author_rank: Unknown
timestamp: February 02, 2016, 06:15:46 pm
content: Quote from: CatalinaWOW on February 02, 2016, 05:04:30 pmHiThe same battery issue applies to the cell phone they are talking to. If the power on both ends is the same (path loss is the same, pretty good bet), they both have the same ERP in each other's direction. The cell phone is omnidirectional, so it gets no benefit from antenna gain. It's only putting out a few hundred mW. If you call that 0 dbW, it's a stretch. A more realistic number is -10 dbW.In order to need 1KW (ERP) out of a base station, it's going to have to service a thousand calls off of a single antenna at 0 dbW. At -10 dbW it's 10,000 calls. Numbers like 30 to 100 calls are a lot more common on a per antenna basis. You also have the issue that not everybody will be at max range. That keeps you well below 1KW even with 10,000 callers.Bob

author: KJDS
author_rank: Super Contributor
timestamp: February 02, 2016, 06:32:31 pm
content: Quote from: CatalinaWOW on February 02, 2016, 05:04:30 pmIf I have a 1W transmitter running an isotropic antenna and the transmitter is 20% efficient then I need 5W power supply and get 1dBW radiated powerIf I use the same transmitter running a 40dBi antenna then I still need a 5W power supply but get a radiated power of 10kW EIRP

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: February 02, 2016, 07:40:52 pm
content: Yes, EIRP, I think it started to make sense now. Cell Map is correct.They have 46 dBm transmitter (40W) and 18 dBi antenna. I checked some data sheets for base stations - many come with 18 dBi sector antennas. So that translates to ...46 + 18 = 64 dBm or 34 dbW. Table on Cell map shows 34.7 dbW.Huh, universe is correct again!So it will in fact result in 5uW/cm2 if you are 120m away and in direct path of antenna beam.