The invention discloses a signal fusion method based on dimension expansion. The signal fusion method is used for expanding a traditional time diversity and frequency diversity system into a dimension diversity system. Different signals are transmitted by utilizing different dimensions which are mutually and independently orthogonal. Transmission of a plurality of paths of data at the same time and under the same frequency is realized; signal amplitudes and bit rates of each path of signals are not restricted by the fusion method. According to the signal fusion method, a real number field is expanded into a two-dimensional complex number field; a virtual number field is expanded into a virtual number two-dimensional space and a virtual number three-dimensional space, even higher dimension; a dimension expansion method with a recursive property is utilized, and dimension expansion with different degrees can be carried out on the signals according to actual requirements, so that the signals with different varieties are transmitted by different dimensions through a certain manner; transmission of multifunctional signals of detection, measurement and control, communication, navigation and the like is realized, and the multifunctional signals do not interfere with one another.