The long, rectangular vertical elements are just that, the actual antenna elements. The smaller round vertical "pole shaped" antenna elements are also antennas.
The small square unit which are out at that same mount circle may be the antenna arrays of another "G" level implementation, or perhaps they are "wifi" hotspot units. But all the rest that lie beneath that outer mount circumference are the actual transceiver amplifier modules for the array elements.
Big ask.
As Wikipedia makes clear, modern cellphone towers carry a number of directi onal antennae, which both transmit to and receive from individual cellphone s.
Cellular phone systems operate on a bunch of - slightly different - freque ncies, so that adjacent cells don't use the same frequencies.
The antenna housings can cover a bunch of different antenna, each sending o r receiving at a different frequencies, whence (presumably) the multiplicit y of cables.
I certainly don't. The closest I've got to cell phone technology - bar an u nsuccessful job interview with Nokia in the late 1980's - was reading the o riginal cell phone paper in the Bell Labs Technical Journal some time aroun d 1980. The Bell Labs patent is dated 1972, but IIRR the paper was publishe d a little earlier - it was definitely in a bound copy of the Bell Labs jou rnal when I read it.
-- Bill Sloman, sydney
I was trying to explain what phone towers are about to my brother, and why each one seems to keep growing in size.
For example, can someone please explain what each piece/type of equipment is on this phone tower?
Also, why are there so many cables leading into each antenna housing?
I am also looking for a photo of the interior of a antenna typical housing but cannot find any. Doesn anyone have one?
Robert Stevens
The picture shows multi-band antenna. There's at least one coax cable per band.
In the US, "band" generally means: (These freq's are approximate, from memo ry)
700 LTE (698 MHz - 787 MHz, assigned in blocks) Cellular (824 MHz - 894 MHz) PCS (1850-1990 MHz) AWS (uplink: 1710-1755 MHz, Downlink: 2110-2155 MHz) WCS (generally, 2305 MHz and higher, assigned in blocks) This is not a complete list.In addition to the coax/transmission lines, there will be control cables to electrically tilt the antenna elements inside the radomes. Tilts are used to fine-tune the coverage pattern. In self-optimizing networks, the tilts may change throughout the day according to traffic demands, or if adjacent network elements go out of service (to correct the resulting macro coverag e), etc.. In cold climates, there may also be power cables for de-icing equ ipment.
One common high-gain cellular base station antenna is the Kathrein 800-1012
I'd have to dig up an "inside view" photo. Inside, it's a bunch of cross-pol antenna elements stacked for high gain. Also, there are several power dividers and plenty of interconnecting cables for the various elements. Some models (not 800-10122) have interior remot e electric tilt (RET) motors to move the antenna elements. The 800-10122 u ses external motors.
The above is just the "antenna", and you asked about equipment on the whole tower. There may be several wireless carriers on a given tower. Some may install their transceivers on the tower top (to avoid transmission line lo sses, and supposedly overall costs). These will look like little square or rectangular boxes, plus their associated fiber optic distribution and DC p ower equipment. The tower may have aircraft obstruction lights, safety cli mbing cables, AM radio station de-tuning wires or equipment, and (for some towers) an assortment of equipment associted with other types of radio user s (i.e., not commercial wireless, such as police/fire, weather radar, micro wave broadcast/backhaul, etc..)
Although you did not ask, some AM broadcast radio towers don't have anythin g on them - the AM station antenna is the tower itself, given the long wave lengths at the AM band.
On a sunny day (Thu, 22 Jan 2015 22:45:52 -0800) it happened Robert Stevens wrote in :
I know nothing about cell phone towers, but I have a superconducting filter from one that I bought on ebay. It runs on 24 V DC... So cellphone towers probably have some 24 V backup? The superconducting LC has a much higher Q factor than a normal LC filter, this is needed for it to pick up cellphones in the middle of noisy environment:
It has a Sterlin cryocooler in it that goes to
,
nment:
jpg
2522.jpgjpg
The traditional cell site runs on 24 or 48 volt battery, with float-charge rectifiers to keep them charged. Batteries will keep the cell site running for several hours up to a few days, depending...
I don't think 3G/4G networks use those cryofilters anymore (and they were n ever terribly popular in 2G as far as I can tell). Modern networks use wid eband modulation technology, which is not as good a fit for these cryo unit s. Also, carriers opt for technology that can be remotely tuned and contro lled, since any network change requiring a visit to every (one of litterall y tens of thousands of) cell sites is an obvious non-starter economically. Cryo-filters required too much care and attention.
I missed this part.. Towers keep growing in size for at least a couple reasons:
1) The carriers keep buying more spectrum at auction. 2) Local building and zoning codes have become so strict that new towers are difficult to build, so carriers buildout their new spectrum on existing towers.Item #2 above is significantly more involved than the broad brush stroke I have given it. There are other reasons for co-locating, but a lack of towers where you need them sort of limits your options.
You don't know the first thing about the technology, just more of your psyc hopathic syndrome:
confabulation
"In psychology, confabulation (verb: confabulate) is a memory disturbance, defined as the production of fabricated, distorted or misinterpreted memori es about oneself or the world, without the conscious intention to deceive.[
1] Confabulation is distinguished from lying as there is no intent to decei ve and the person is unaware the information is false.[2] Although individu als can present blatantly false information, confabulation can also seem to be coherent, internally consistent, and relatively normal.[2] Individuals who confabulate present incorrect memories ranging from "subtle alterations to bizarre fabrications",[3] and are generally very confident about their recollections, despite contradictory evidence.[4] Most known cases of confa bulation are symptomatic of brain damage or dementias, such as aneurysm, Al zheimer's disease, or Wernicke-Korsakoff syndrome (a common manifestation o f thiamine deficiency caused by alcoholism)."
Illustrate for us, you retarded bastard, just what part is false? Where did I deceive?
I think Fred Bloggs had an agenda of attacking folks in technical newsgroups.
His posting behavior bears immutable evidence of this fact.
Someone in the nation he has chosen to invade, should go gather his lame, retarded ass up, and stuff the idiot into a rubber room.
Care to elaborate on turning down that nomination from the Nobel prize committee? Was that before or after Google offered you the job of chief of technology development?
On a sunny day (Thu, 22 Jan 2015 05:31:18 -0800 (PST)) it happened mpm wrote in :
Na, these sterling coolers can run for years without any maintenance. Ever hear the humming sound near a cellphone tower? It is these.
snip
Care to show the group where and when any such claim was ever made?
That's right. You can't. Becaiuase no such statement or claim was ever made.
Only the Bloggs retard, in his infinite delusion, makes such flase remarks.
Hey, FreddyTard, YOU fit the definition of the term you attempt to accuse others of. Busted!
There was never any such claim of this either.
You lose, again, retard Fred Bloggs, the Usenet village idiot.
Looks like you're getting flustered, loony. And you're such a sickening little parrot with your unoriginal attempts at insult.
The new 700, 1700, 2100MHz frequencies were added in the last few years, requiring the addition of new antennas.
Each radome has 4, 6, 8, or more antennas inside. Usually, they are on the same frequency band. In this installation, they go to TMA (tower mounted amplifiers), primarily to reduce coax cable feedline losses: Those are the mid size boxes in the photos. The smaller boxes are probably external DC injectors to power the TMA's, which are rather unusual. They're usually built into the TMA's.
Inside the antenna or the TMA? Later... I gotta run.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Each housing contains multiple elements of varied tuned resonances. The 'RF transparent' cover simply keeps wind and weather from affecting the elements' placement on the stalk, eliminating degradation from such effects.
Several stalks get arrayed such that the coverage area is wider, and also to be capable of higher call density needs in a given area.
Why don't you ask Fred Bloggs what they are for. He is the group expert on electrical engineering. N O T !!!
He very likely could not even tell you what type of coax is used, and I very likely can, because I know what the industry uses hundreds of miles of every year.
Here is but one document I found which declares how (some of) the towers get fed.
snip
Was calling you a piece of fecal matter, and declaring your mother's career path "obscenities" or statements of fact?
I vote the latter.
It was a response to YOUR pathetic insult, child. Your pathetic rationale is what is being displayed here.
I answered the poster in a contributory manner. All you have done is INVADE the thread with your typical "Fred Bloggs, the sed group abuser" tripe. Par for the course for you.
Maybe in your next life, you will accomplish something other than making yourself out to be a major fool. You have failed miserably in your current, dung beetle mentality iteration.
Decidedly, it is you whom lacks any modicum of any intelligent thought, much less any rational one.
Objects of to be are predicate nominative, so that should be "...it is you who..."...lemme see, that puts you at less than 5th grader level education. You're just an uninteresting lowbrow.
Define "typical"?
Scroll to "February 28, 2013 - COMMENTARY"
Always amusing to see anything southwestern tagged with saguaro as they really only live in the Sonoran Desert. E.g., there are some movies which are "set" in other places yet, due to being shot here, have tell-tale saguaros visible in their footage. It would be like seeing wild palm trees in a movie allegedly set in upstate New York! :-/
You are a group invading, thread noise injecting, retarded insult mouthing, petty little unibrow Neanderthal.
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