Bandwidth of Timed Automata - 3 Classes

  • Bandwidth - Information per unit time
    • For discrete languages we can just count the number of words, not possible for timed words because time is real
    • We define up to some precision
      • We say two words are less than epsilon away, if they have the same set of letters(ordering can change)
      • We can move the letters in the first words in time by at most each to get the second words
  • -net: A set of points such that any point in the Metric Space is at most away from the space
  • Orbit Graphs - defined for each path
    • We link vertices whenever it is possible to go from to (start and end)
    • We represent a vertex by 2 connected(special connection) nodes of a graph(representing start and end times) and we make connection between both ends of the vertex(both nodes)
    • These can be represented as adjacency matrices and multiplication of matrices represents composition of paths
    • Having Orbit Graphs for just edges lets us generate it for all paths
    • The matrix interpretation also gives a handy computation tool to deal with every configuration of clocks(even with fractional values, obviously)
    • Good for reachability