BRX-XLR User Guide 6 180-0145-001-R01
1 General Description
The Broadband Reach Extender –Extra Long Reach (BRX-XLR) is a fully integrated solution that
extends the reach of deployed ADSL / ADSL2+ DSLAMs or MSANs to deliver higher bandwidth
services to underserved or unserved markets. For example, it extends the reach of a 10 Mbps
downstream service from 9,100 feet (2.8km) to 12,500 feet (3.8 km) on 26 AWG / 0.40mm gauge
copper, an increase of almost 40%, and the same level of increase is achieved for larger size
cables. Furthermore, this 40% increase in reach results in an estimated 100% increase in CSA
(Customer Serving Area) since the area served is proportional to the square of the lineal distance.
Another way to look at the benefits of this same function is that a client that is situated at 12,500
feet (3.8km) from the DSLAM, on a 26 AWG (0.40mm) copper pair will see the downstream
bandwidth increase from approximately 5Mbps to over 10Mbps. Over longer distances, the
bandwidth improvement ratio is between 2 and 5. It is important to note that these benefits are
obtained without the need to change the DSLAM/MSAN or the user CPE. By significantly
increasing the effective bandwidth and reach of existing xDSL lines, operators can deliver true
broadband speeds to each of their subscribers, even those located in remote areas or currently
located too far from the DSLAM to receive any service.
2 BRX-XLR Main Advantages
Extends up to 100% the ADSL/ADSL2/ADSL2+ Customer Serving Area (CSA).
Improve effective bandwidth typically by a ratio of 2 to 5 for ADSL/ADSL2/ADSL2+ loops.
No extra power required. The BRX-XLR uses less than 2mA from the -48V sealing
current of the POTS line.
Flexible Shelf design allows more subscribers to be added in the future.
Turnkey pedestal option available.
Auto calibration, no software to configure or dip switch.
Easy to install, deploy, and maintain.
3 Bandwidth Performance and Placement Flexibility
3.1 Expected Bandwidth Improvement with BRX-XLR
The BRX-XLR automatically adjusts itself to optimize performance. The BRX-XLR provides noise
filtering and a gain (amplification) of the signal (in the xDSL band only) in the downstream and
upstream direction of up to 16 dB and always within the acceptable signal strength allowed by the
xDSL standards for the Spectrum Mask of ADSL2+ and ADSL. As such, the amplification gain is
higher on longer loops (i.e. loops where the attenuation of the signal is greater due to the longer loop
length). A key factor in its performance is that the BRX-XLR significantly improves the signal to noise
ratio seen by the CPE (in the downstream direction) and the DSLAM (in the upstream direction).
