Approximation Algorithms for Channel Assignment with Constraints

  • Jeannette Janssen
  • Lata Narayanan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1741)


Cellular networks are generally modeled as node-weighted graphs, where the nodes represent cells and the edges represent the possibility of radio interference. An algorithm for the channel assignment problem must assign as many channels as the weight indicates to every node, such that any two channels assigned to the same node satisfy the co-site constraint, and any two channels assigned to adjacent nodes satisfy the inter-site constraint.

We describe several approximation algorithms for channel assignment with arbitrary co-site and inter-site constraints and reuse distance 2 for odd cycles and so-called hexagon graphs that are often used to model cellular networks. The algorithms given for odd cycles are optimal for some values of constraints, and have performance ratio at most 1+1/(n−1) for all other cases, where n is the length of the cycle. Our main result is an algorithm of performance ratio at most 4/3 + ε for hexagon graphs with arbitrary co-site and inter-site constraints.


Approximation Algorithm Bipartite Graph Cellular Network Channel Assignment Performance Ratio 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Jeannette Janssen
    • 1
  • Lata Narayanan
    • 2
  1. 1.Department of Mathematics and StatisticsDalhousie UniversityHalifaxCanada
  2. 2.Department of Computer ScienceConcordia UniversityMontrealCanada

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