antenna type??

Alienware;

They are definitely omni whips. must be out in the boonies. :browani:

 

Omni's are also why CellOne (Dobson) is in trouble with the FCC for not complying with Phase 2 E911 requirements.

 

If they want to come into compliance with the FCC, most likely.

 

Not really. The problem is that their current vendor (TruePosition) doesn't know how to properly locate on an omni directional transmitting site. The GeoMetrix product team came up with a patented solution for this using a proprietary algorithm on the GSM channels that uses time difference of arrival, along with something called 'bore sight'. Making assumptions of the azimuth (within a range) based on the antenna being used on a multiple antenna site (such as pictured) and timing to determine distance they can be compliant. Remember, the compliance is calculated using the erlangs (call volume measurement) in a given boundary (usually a state). As long as the entire state isn't omni directional coverage, they are fine. Also, they can use neighbor site hearability using BCCH to assist in the 'bore site' direction by mapping where you are based on statistical probability of the particular neighbor sites location and your timing to it's wireless location sensor.

BTW: Those antennas are called Bogners. That is the name used generically these days for big fat fiberglass whips, usually relatively high power. It originates from Richard Bogner of Bogner antenna. His broadcast antennas
account for a fair proportion of all full power antennas. He is one of
the RF pioneers of the TV age. A popular design type made by Bogner is the pictured tubular design with its surface populated with discreet radiating elements. These form antenna arrays.

 

wirles;

I would agree that TruePosition is part of their problem but unless they are going to eat alot of money that's who they'll be using for E911. The best system seems to be a combination of GPS based handset and triangulation based systems but even that will have holes (like a DAS system)

 

A DAS is easy to deal with on GSM. It is called fixed site locate. You create a centroid lat/long in the database that gets provided to the PSAP on a 911 call made via the DAS radio. If it is a large structure (DFW airport, or Bill Gates' home) you can sectorize strands of the fiber from the hub and each one has a centroid of it's own. This, along with the 'averaging' of accuracy for the market maintain compliance. Andrew (GeoMetrix) is the innovator in 'virtual' site locates using this fixed method and proprietary patented devices that work in tandem with a DAS. I'll take a properly designed and installed TDOA/AOA system over A-GPS anyday.

 

Initially many carriers used an omni design because they didn't need the capacity of a sectorized system. They wanted less sites with larger propogation rings. In larger markets (not the boonies ) they need smaller sites capable of more call volume, therefore sectorization and more precise coverage areas.

 

Yes those are Bogner style antennas. Those are 20ft tall 12 db gain and were designed for max distantance and were designed for analog service where the towers where alot farther apart. These are found mostly in RFB and in the thumb area. There are alot of these still in use in the sticks so to speak. Panel antennas are a better alternative as they are cheaper and are rated for 18 db gain and cost $1000 over $15000 for Bogners.

 

We have already converted alot last year. I know they have plans to do alot more. When or where I dont know yet.

 

I have 30 to 40 Bogners for sell BCR12 12db gain A,B,D,H,O some new and some used. How much do u think i can get for each now days? (cell 318-537-0700 Kevin)

 

Couldnt tell you for sure. I dont know what the demand is for those anymore. The industry is pretty much trying to get away from using alot of omni sites and going with panels. The Bogners area a pain to deal with cause of their size.

 

Ya thay are big I'v put one up a 300 foot tower.

 

Yes those are definately omni directional antennas