7、信道分配近似算法与加权和速率优化

信道分配近似算法与加权和速率优化

一、单信道固定干扰半径调度算法

1.1 贪心单信道算法介绍

为了解决信道调度问题，提出了贪心单信道算法（Greedy - Single - Channel）。该算法是一种 (O(1), O(1)) 近似算法，相较于以往的单边近似界限，它的双边近似界限有所改进。

算法步骤如下：

Algorithm Greedy - Single - Channel(G, t)
Input: a weighted graph G, and a distance parameter t for the largest distance of interference.
1. Sort all edges by the decreasing order of their weights and put those edges in a list L.
2. Let L′ = ∅;
3. Repeat
    3.1 Select an edge e = (u, v) with the largest weight from L;
    3.2 If e is not being interfered by L′
        then assign the channel K to e and put (e, K) into L′;
    3.3 Remove e from L;
4. Until L is empty;
5. Output L′;
End of Algorithm

判断新边 $e$ 是否会在某一信道 $K$ 受到干扰时