Node+0 in a Flash

An Easy Method to convert from Node+5 to Node+0 while adding both forward and reverse bandwidth

While contemplating a  methodology for a node + 5 topology to a node +0 topology it suddenly struck me that if we combined the aspects of RFoG, 4Cable TV Inc.’s PowerMiser Technology and a little know piece of technology called ROPA (Remote Optically Pumped Amplifier). We would continuing to use the existing Coax to provide power to the new LENodes (Line Extender Nodes), or old Line Extender Locations. Alternatively power could be supplied from the customer premise or from solar cells.

If we look at a typical 4 output node, at 75,000 feet fed with a 1310 nm forward fiber and a  second fiber for a 1310 return.  By replacing the 1310 transmission to the node with a 1550 signal and feeding forward signals on both fibers at a level of 13 dBm and  using a WDM to combine the returns, we now have 2 incoming fibers to the Node both at approximately 5 dBm.  We also insert at the headend a remote pumping signal at 1480 nm at a level of 300mW we will have approximately 17 dBm of 1480 nm light at the Node location.  By running both wavelength through a length of erbium dope fiber at the remote location we will get approximately a 17dBm output. Splitting both fibers we would then have 4 outputs of 13 dBm which is more than enough light to power to feed up to 128 LENodes or previous line extender locations.

Plug in modules would be constructed that would drop into the existing LE housings, with the lids being replaced with lids that have been modified with access ports for the fiber.  4Cable TV’s PowerMiser technology can be used to build a node that would accept a -5dBm optical input and provide a 36-52 dBm output with a 48 dB  CN and distortions at 63  dBc  with a power consumption of 5 watts.  At this low power consumption each LENode could have a dual built in NiMH battery pack which would operate the unit for 0ve 24 hours.  At the end of each 24 hour period the battery packs would automatically switch so that on would always be fully charged and the LENode would operated without being connected to the coaxial power source and its potential for causing an outage.  The LENodes would be built in 2 configurations a single and a dual output.  The duals would be used at the first LE out of the System amps which would require that the taps between the system amp and the LE be reversed but it would remove the system amps from the system completely. Provisions would need to be made for the occasional line out of a system amp that did not have an LE. 

A transitional temporary Node would be available for use for convenience during conversion.

The LENodes would be 1.3 GHz devices and could easily encompass a plug in high return split with a 1610 return laser for an additional 1 GHz of return bandwidth.

Contact Steve Richey steve@4cable.tv or 843-347-4933