Analyze the intra-flow contention mechanism in Mesh wireless multi-hop paths to reveal the mechanism of multihops start-to-end bandwidth bandwidth loss. It is pointed out that in multi-hop relay systems with more than 6 hops, there exists an optimal convergence ratio that can constrain the 1/n decline trend of multihops start-to-end bandwidth, whereas systems with 6 or fewer hops cannot constrain this 1/n decline trend. The key factor determining the existence of an optimal convergence ratio in multihops relay systems is the ratio of carrier sensing distance to stable communication distance, ΔS. When path nodes are uniformly distributed with ΔS=2, the multihops start-to-end bandwidth has an optimal convergence ratio of 1/6. The boundary characteristics of wireless transmission in mines make ΔS≈3, resulting in an optimal convergence ratio of 1/8 for multihops start-to-end bandwidth when path nodes are uniformly distributed in mines. The asymmetric and unstable characteristics of wireless coverage in mines prevent nodes from being uniformly distributed, and both characteristics have the effect of shortening the carrier sensing distance. In a simulated mine with a 10-hop path, it is derived that the optimal convergence ratio of multihops start-to-end bandwidth under the combined influence of these two characteristics is 1/5. Based on the idea of constraining contention diffusion, a method of hybrid chain network construction with segmented series of heterogeneous frequency paths is proposed, which uses frequency division to constrain the intra-flow contention range within each path. Experiments show that when the number of wireless links exceeds 10 hops, the start-to-end bandwidth of the chain network is greater than the multihops start-to-end bandwidth of traditional Mesh multihops paths, and the convergence ratio is also greater than 1/n, verifying the feasibility of this method in constraining the 1/n decline trend of multihops start-to-end bandwidth.
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