By David Urban, Comcast
This paper compares three techniques for increasing the upstream capacity and peak upload speeds for a hybrid fiber coaxial cable network. The first technique is to increase the spectrum utilization and signal robustness in the 5-42 MHz band. The second technique is to allocate more upstream spectrum by changing the mid-split cross over point between the upstream and downstream bands.
This paper shows some measurement results to help quantify the levels and extent of interference to televisions, set top boxes, and digital transport adapters to upstream transmission in the 42-85 MHz band with downstream signals in the 108-750/860/1002 MHz band. The last technique is the use of spectrum above 1 GHz. The advantage of this approach is that it can be built incrementally as needed without impacting the 5-1002 MHz HFC plant and services.