What is an ADSL repeater?A repeater is a product that is installed along a communications route to increase the distance a signal will travel. They are installed at a pole, pedestal or cabinet and come in two varieties: amplifiers and regenerators. Amplifiers increase the signal level of the analog transmission signal; regenerators demodulate the signal to binary then remodulate into the original transmission frequencies. Because regeneration restores the signal to binary, an indefinite number of regenerators can be placed on a line and is the preferred choice for services like T1 that have no distance limits. Because of the simplicity of the amplifier circuits, amplifiers are lower cost than regenerators. The primary difference between T1 at $800 / month and ADSL at $40 / month is that ADSL can go long distances without regenerators. But even ADSL has its limits. Because ADSL is a low cost service, it is generally felt that the additional cost of regeneration cannot be supported. There are companies that build ADSL loop extenders that aren't repeaters. These products have special equipment on the Central Office end and customer end that either amplify the signal or convert it into a different technology (like g.shdsl) that can be repeatered. If additional amplification in the C.O. were a good idea, the DSLAM and modem makers would just run their products at higher power. This additional amplification creates noise on adjacent pairs and is not compliant with T1.417 spectrum management. Converting to g.shdsl or other technologies has problems too. First of all, if you are going to convert to g.shdsl, why not just start out with g.shdsl in the DSLAM? G.shdsl technology has limited downstream speed so they are really only useful to extend services to the most distant customers. Because the technology has so many components (special C.O., regenerators, CPE), it is much more expensive than ADSL amplifiers and begins to approach T1 in the cost to the service provider. Widearea was the first company to manufacture and build an ADSL amplifier/repeater and has more lines deployed than any competitor. The main competitors in the ADSL Repeater market are: 3M / Charles Industries / Phylogy - TripleStream, AdrenaLine, Line Conditioner- This technology is marketed under different private labels by several companies in different parts of the world. The basic technology is owned by Phylogy.
The most important problem with the 3M / Charles / Phylogy technology is that the amplification is not automatic-gain adjusting. Because of this, it is deployable in only a very narrow range of locations. If you vary from that ideal spot by more than a few hundred feet, the performance of the extender drops significantly. - Because it does not automatically adjust gain, changes in line resistance are a big problem. Dramatic swings in bandwidth will occur from the hottest to coolest days.
- The product is huge so you will not be able to find space for them so easily.
It is more expensive. The maximum bandwidth is lower. Fewer Lines in service, shorter service history. No bandwidth estimator
Other China Derivitives: Versatek / WT / Zhuzhou - ipTV Accelerator- Originally, the Widearea product was distributed in China as an OEM product with a different OEM in each province. Today, Widearea maintains a network of distributors in each provice in China and on each continent around the world. Two of these Chinese distributors copied the product as best they could and are selling it under their own label. Because they do not understand the underlying principles of operation, they have not been able to keep up with Widearea. The physical look of the clones are very similar so they are easy to spot. These clones of the Widearea technology all lack automatic gain control.
One of these clones has adopted a manual gain adjustment that will allow you to adjust the gain to the installation location. - Because it does not automatically adjust gain, changes in line resistance are a big problem. Dramatic swings in bandwidth will occur from the hottest to coolest days.
- This product family has a product called ipTV accelerator, but it does not improve speeds above 15 Mbits.
No IP66, NEBS, UL, CE, FCC.... The maximum bandwidth is lower. The reach is less. Fewer lines in service No Bandwidth estimator
To buy an ADSL Repeater go here.
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