Network Planning of the CATV communication networks

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Network Planning of the CATV communication
networks

• Arthur, K. W. Peng, OPLAB
• d6725005_at_im.ntu.edu.tw
• Advisor Frank Yeong-Sung Lin
• April 22, 2005

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Agenda

• Introduction
• Problem Description and Formulation
• Formulation Analysis and Reformulation
• Numerical Experiments
• Conclusion
• QA

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CATV Communication Network Technology
The Network Structure of CATV Networks
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Network Planning --- Traditional Approaches

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• Figure 2-10

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• Similar to the design of downlink.
• Noise Funneling
• Limit the number of branch and amplifier.
• Addressable Bridger Leg Switch
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CAD Tools

• The traditional way is calculation-intensive and
  repetitive.
• Comparison of the CAD toolsYermolov,2000
• CATV CAD Gen Enterprise Ltd.
• Symplex Suite of software SpanPro Inc.
• Program SystemLode Data Corporation
• CADIX International Inc.
• Cable Tools Goldcom Inc.
• Feature
• Auto-tracking the signal quality.
• Helping the design to calculate the network
  requirement, cost, etc.
• The design is still depend on the experience of
  the network designer.

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CATV Network Planning Tools

• Stand-alone version

• Web-based version

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Mathematical Formulation and Network Optimization

• Basic ideas formulate the network and using
  network optimization technique to find the
  optimal solution.

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Performance Requirements

• Performance requirements in downstream
• CNR (Carrier to Noise Ratio) ?43dB
• X-MOD (Cross Modulation ) ?-46dB
• CSO (Composite Second Order) ?-53dB
• CTB (Composite Triple Beat) ?-53dB

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Performance Requirements (contd)

• Performance requirements in upstream

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Problem Formulation

• Problem description
• Given
• downstream performance objectives
• upstream performance objectives
• specifications of network components
• cost structure of network components
• number and position of endusers
• terrain which networks will pass through and the
  associated cost
• Determine
• routing
• allocation of network components
• operational parameters (e.g., gain of each
  amplifier)

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Problem Formulation

• Features
• Nonlinear problems
• Hard to solve directly by standard methods
• Some techniques needed
• Problem Decomposition
• Steiner Tree Problem
• Network Optimization
• Geometric Programming
• Posynomial form
• Gradient-based Optimization

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Problem Decomposition and Reformulation

• Part I Steiner Tree Problems

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Problem Decomposition and Reformulation (contd)
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Problem Decomposition and Reformulation (contd)

• Heuristic approximation algorithms
• Minimum Cost Paths Heuristic (MPH)

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Problem Decomposition and Reformulation (contd)
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Problem Decomposition and Reformulation (contd)

• Part II

s.t.
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Problem Decomposition and Reformulation (contd)
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Problem Decomposition and Reformulation (contd)

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Problem Decomposition and Reformulation (contd)
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Solution Approaches

• Posynomial problem
• aij arbitrary real numbers
• ci positive
• gk(t) posynomials

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Solution Approaches (contd)

• Dual problem

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Solution Approaches (contd)

• Penalty method
• Steepest descent method
• Rounding procedure

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Computational Experiments

• Solution modules

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Computational Experiments
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Computational Experiments

• The constructed steiner tree

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Computational Experiments

• Deciding the locations and parameters of
  amplifiers

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Conclusion

• It is feasible to use mathematical programming
  methods in CATV network planning
• The solution provided by this approach can be
  used to evaluate the QoS in many situation.
• As a core module, we can add more features
• New network components
• New Services

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Future Research Directions

• Network Planning and Management
• CATV network planning and optimization
• Layering
• QoS
• Fault tolerance/Reliability
• CATV network performance
• Capacity management
• Admission Control

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Q A