The invention discloses a non-orthogonal multiple access
downlink transmission method for a space array communication, and belongs to the technical field of space communication. The method comprises the following steps of: firstly, constructing a communication scene, the ground
base station superimposes and transmits signals transmitted by the space
base station, and superposed signals form a mixed
signal; performing a
millimeter wave directional communication between the ground
base station and each of the space base stations to obtain a channel
response vector corresponding to each space base
station; selecting the channel
response vector on the strongest path of the space base
station as a valid channel
response vector; making the appropriate sort of the effective
channel gain by usingthe
beamforming vector w, in connection with |h<1><H>w|<2> is greater than or equal to |h<2><H>w|<2>, a space base
station 1
decodes to transmit a
signal s2 and eliminates and re-
decodes to transmit
signal s1, the space base station 2
decodes to transmit a signal s2 and obtains the
reachability of each space base station, when the sum of
reachability is maximized designing the condition of constraints that the joint power allocation and
beamforming need to meet, and solving the condition of constraints to obtain a scheme of power distribution corresponding to each space base station and a
beamforming of the ground base station. According to the non-orthogonal multiple access
downlink transmission method for space array communication, the spectrum efficiency is effectively improved, and thecalculation complexity is low.