A high-dimensional signal transmission method is provided. The method generates M M-dimensional first signals on the basis of M original signals and generates M M-dimensional second signals on the basis of a precoding signal and of the first signals, and finally, a transmitter sums all of the second signals and then transmits by utilizing M subchannels. As such, each subchannel carries information of the M original signals; hence, when any subchannel experiences deep fading, the deep fading is shared jointly by M signals, thus preventing the deep fading from causing a particularly severe impact on any signal. Moreover, all of the original signals can be recovered by utilizing the signals on the other subchannels, thus increasing the systematic resistance against subchannel deep fading. Meanwhile, the system implements the parallel transmission of the M original signals, thus ensuring the throughput of a communication system.