Abstract: A spatial position-dependent I/Q domain modulation method, dual domain modulation method and multiple access communication method are provided. The methods eliminate the dependence of physical layer secure communication on channel state information, and realize the function that a receiver at an expected position can communicate normally, while an eavesdropper at other positions cannot receive a signal or can only receive a wrong signal. The security capability of a wireless communication system is improved from the spatial dimension. The multiple access communication method can realize the distinguishing of multiple users according to precise spatial position points. Even if a plurality of users are located in the same sector in an angular domain, as long as the spatial positions of these users are different, the method can be used to perform multiple access communication, thereby further improving the spatial multiplexing rate of the system and increasing the system capacity.

Abstract: A high-dimensional non-orthogonal transmission method is provided. In the method, signals of various users are mapped to form high-dimensional signals, and the high-dimensional signals are pre-coded, such that non-orthogonal transmission is realized in a higher dimension. Moreover, different users perform matched receiving on respective signals, and non-orthogonal transmission signals can be recovered merely by means of a receiver with a linear complexity. By means of the method, multi-user data non-orthogonal transmission can be realized without depending on conditions such as user pairing and collaboration, and various users do not need to perform iterative feedback, such that the detection complexity of non-orthogonal multi-user signals is significantly reduced.

Abstract: 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.

Abstract: A phase domain modulation method dependent on a spatial position is provided. The method mainly includes the following steps: a transmitter and a receiver perform time synchronization to obtain a synchronization time; the transmitter performs a phase domain precoding operation on an original signal to obtain a phase domain pre-coded signal; the receiver receives the phase domain pre-coded signal, obtains a phase domain initial reception signal, and performs a phase domain matching operation on the phase domain initial reception signal to obtain an estimation of the original signal.

Abstract: A random phase modulation method depending on a communication distance is provided. In the method, time synchronization is carried out by means of a transmitter and a receiver, a local random signal is generated, and an original signal to be sent is pre-coded according to a transmission delay and the generated local random signal, such that random phase modulation depending on a communication distance is realized, potential security brought about by positions of the transmitter and the receiver is fully utilized, a receiver at an expected distance position can receive a signal with a correct phase, and a receiver at another distance position receives a signal with a scrambled phase, thereby improving the secure communication capability of a wireless communication system in terms of the dimension of space.

Abstract: 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.

Abstract: A random phase modulation method depending on a communication distance is provided. In the method, time synchronization is carried out by means of a transmitter and a receiver, a local random signal is generated, and an original signal to be sent is pre-coded according to a transmission delay and the generated local random signal, such that random phase modulation depending on a communication distance is realized, potential security brought about by positions of the transmitter and the receiver is fully utilized, a receiver at an expected distance position can receive a signal with a correct phase, and a receiver at another distance position receives a signal with a scrambled phase, thereby improving the secure communication capability of a wireless communication system in terms of the dimension of space.

Abstract: A spatial position-dependent I/Q domain modulation method, dual domain modulation method and multiple access communication method are provided. The methods eliminate the dependence of physical layer secure communication on channel state information, and realize the function that a receiver at an expected position can communicate normally, while an eavesdropper at other positions cannot receive a signal or can only receive a wrong signal. The security capability of a wireless communication system is improved from the spatial dimension. The multiple access communication method can realize the distinguishing of multiple users according to precise spatial position points. Even if a plurality of users are located in the same sector in an angular domain, as long as the spatial positions of these users are different, the method can be used to perform multiple access communication, thereby further improving the spatial multiplexing rate of the system and increasing the system capacity.

Abstract: A phase domain modulation method dependent on a spatial position is provided. The method mainly includes the following steps: a transmitter and a receiver perform time synchronization to obtain a synchronization time; the transmitter performs a phase domain precoding operation on an original signal to obtain a phase domain pre-coded signal; the receiver receives the phase domain pre-coded signal, obtains a phase domain initial reception signal, and performs a phase domain matching operation on the phase domain initial reception signal to obtain an estimation of the original signal.

Abstract: A high-dimensional non-orthogonal transmission method is provided. In the method, signals of various users are mapped to form high-dimensional signals, and the high-dimensional signals are pre-coded, such that non-orthogonal transmission is realized in a higher dimension. Moreover, different users perform matched receiving on respective signals, and non-orthogonal transmission signals can be recovered merely by means of a receiver with a linear complexity. By means of the method, multi-user data non-orthogonal transmission can be realized without depending on conditions such as user pairing and collaboration, and various users do not need to perform iterative feedback, such that the detection complexity of non-orthogonal multi-user signals is significantly reduced.