Disclosed is an SCMA (Sparse Code Multiple Access) optimization
codebook design method, comprising the following steps: firstly, setting an SCMA
codebook parameter; secondly, rotating a QPSK (Quadrature
Phase Shift Keying)
constellation an angle anticlockwise to maximize the minimum
Euclidean distance between projection
constellation points of QPSK on two dimensions; thirdly, performing dimensional and point extension on C to obtain a mother
constellation C+, and then rotating the C+ to construct a total constellation map c of df users on a single
resource block to maximize the minimum
Euclidean distance between the users; fourthly, rotating the total constellation anticlockwise to maximize the minimum product distance of each user on the
resource block, and then mapping the mother constellation C+ to an SCMA
codebook of multiple users with the use of the optimized rotating angle and in combination with a
factor matrix F; and finally, in a
Rayleigh fading channel, interweaving Q channels of
QAM (
Quadrature Amplitude Modulation) symbols, obtained by mapping on each
resource block, of the users. The SCMA codebook designed by the method has good capability of resisting
noise, interference and
fading.