The utilizing of photonic technology to generate microwave signals is a popular research topic and is widely used in communication systems, signal processing, radar and other fields. The method of using photonic technology to generate optical pulse signals with triangular time domain characteristics is imposed. And the all-optical method and electro-optical method including spectral control and time domain superposition is introduced in detail and compared. The advantages and disadvantages are analyzed in terms of pulse repetition frequency tuning capability, pulse duty cycle, pulse type and system structure stability.