Cisco Prisma II bdr Digital Reverse 4 1 Multiplexing System 安装指南
Conclusion
The signal processing functions in the 4:1 bdr product create a signal dependent
noise level that makes the real system performance difficult to predict from the NPR
performance curve. NPR measurements provide an overly restricted prediction of
system performance. For this reason, the system design parameters and traffic
modeling should be considered when predicting the system performance.
noise level that makes the real system performance difficult to predict from the NPR
performance curve. NPR measurements provide an overly restricted prediction of
system performance. For this reason, the system design parameters and traffic
modeling should be considered when predicting the system performance.
Although the NPR curves would predict an end-of-line performance of about 10 dB
for a 4:1 optical link, after taking into account more realistic spectrum loading, signal
statistics and RF combining effects, the system performance turns out to be closer to
15-16 dB. This shows that for the vast majority of systems, the 4:1 performance will
be very close to the performance levels of the standard 2:1 reverse path systems.
for a 4:1 optical link, after taking into account more realistic spectrum loading, signal
statistics and RF combining effects, the system performance turns out to be closer to
15-16 dB. This shows that for the vast majority of systems, the 4:1 performance will
be very close to the performance levels of the standard 2:1 reverse path systems.
There is a minimal, if any, performance penalty when comparing a 2:1 digital reverse
system with a 4:1 bdr system. However, the price implications are significant.
Consider that the cost of International Telecommunications Union (ITU) optics and
passive components are cut in half using the 4:1 bdr system. The quantities of the
highest cost components in the optical link are reduced by half. Additionally, there
are indirect cost savings with fewer wavelengths required, and fewer fibers required
due to the more efficient utilization of each wavelength.
system with a 4:1 bdr system. However, the price implications are significant.
Consider that the cost of International Telecommunications Union (ITU) optics and
passive components are cut in half using the 4:1 bdr system. The quantities of the
highest cost components in the optical link are reduced by half. Additionally, there
are indirect cost savings with fewer wavelengths required, and fewer fibers required
due to the more efficient utilization of each wavelength.
4000819 Rev B
Improving the Performance and Capacity of Digital Reverse Systems
17