In recent decades, mobile communication has entered a period of rapid development, it is closely related to people's daily lives and has become a necessity in people's lives, the current mobile communication is in the second generation to third generation of the phase transition.The modulation is a key technology in mobile communication, and it is important for mobile communication to select an appropriate and high effective modulation mode according to different wireless channel characteristic. The appearance of the software radio is a huge impetus to the development of mobile. Constructing a generic, standard, modular hardware platform and realizing the radio function by software instead of hardware can enhance the system flexibility greatly. It is flexible for the digital modulation by software, and it may realize different modulation mode through the airborne to be downloaded and therefore it suits the different communication systems.After reading massive domestic and foreign literature about digital modulation and software radio, In the paper, deeply studying the principles of digital modulation methods as well as the advantages and disadvantages, I designed a software radio platform in order to achieve the corresponding digital modulation.
