According to the requirement of radar radiation signal establishment in complicated electromagnetic environment, put forward the multi-radar simulation technology in single channel based on genetic algorithm. By genetic algorithm, solve the optimal time of arrival (TOA) of multi-radars simulation in single channel, by setting different initial parameters, the simulation calculation shows that equivalent simulation can be completed under the condition of minimum loss probability, which provide data pre-analysis for optimal configuration of simulation system. The simulation results show that the technology can provides a practical solution for equivalent simulation in complicated electromagnetic environment.