Magnons possess spin angular momentum without electric charge, thus magnonic devices can avoid the high energy consumption caused by Joule heating in conventional electronic devices. Microwave antennas are one of the simplest and most effective means to excite spin waves. However, for a given microwave antenna, it can only excite spin waves in a very narrow frequency range, and there is an obvious excitation forbidden band. Therefore, the efficient broadband excitation of spin waves remains a key challenge in magnonic devices. This article proposes a method for achieving wideband and high-efficiency excitation of spin waves with the assistance of spin-transfer torques (STT). Theoretical analysis and simulation results of micromagnetism show that the excitation efficiency of spin waves is highly dependent on the width of the excitation antenna and the excitation frequency, and the spin waves can only be excited efficiently within a narrow frequency range. By introducing STT and modulating the current density, the spin waves can been effectively excited that were previously difficult to excite, and the efficient excitation of spin waves are achieved in a wide frequency range. The wave interference theory are adopted to account for these phenomena, and the theoretical predictions are in excellent agreement with the simulation results. This method of improving the excitation efficiency and bandwidth of spin waves is suitable not only for microstrip antenna excitation, but also for other excitation methods. Furthermore, it is also found that STT can give rise to asymmetric excitation of spin waves. The STT not only has a positive significance in the excitation of spin waves, but also offers valuable insights into interference regulation, the generation of coherent spin waves, and the unidirectional transmission of spin waves. This method is more reliable than those that directly use multi-antenna or multi-pulse to excite coherent spin waves, and the manipulation of phase difference is simpler and more accurate, and it is more efficient and adaptable than some unidirectional transmission using non-reciprocity. These results have significant implications for the excitation and propagation control of spin waves, and offer a novel strategy for designing next-generation magnonic devices.