Local heterogeneous networking is a key technology for addressing communication blind spots and communication island in complex network environments of distribution network. However, traditional heterogeneous networking optimization methods face challenges of the difficulty of incomplete spatial-domain coverage, competition for communication resources, and slow optimization convergence speeds. Therefore, this paper constructs a distribution network heterogeneous networking architecture for spatial-domain coverage void and temporal-domain state delay minimization. A joint optimization problem for relay scheduling and time scheduling is formulated to minimize the average number of spatial-domain coverage voids and end-to-end queuing delay. A joint optimization algorithm of relay scheduling and time scheduling for spatial-domain coverage void and temporal-domain state delay minimization is proposed. In the first phase, the proposed algorithm optimizes the relay scheduling strategy based on spatial-domain coverage void-aware matching, preventing the formation of future spatial-domain coverage void by introducing a coverage void awareness value in the construction of matching preferences. At the same time, it resolves resource competition issues by comparing the preference values of conflicting devices. In the second phase, the algorithm optimizes the time scheduling strategy based on an improved ant colony algorithm, accelerating the optimization convergence speed by introducing temporal-domain state delay awareness in the pheromone update. Simulation results show that the proposed algorithm has excellent performances in terms of temporal-domain state delay and coverage void rate.