A data transmission method, comprising the steps of: determining Q transmission resources to be used and Q complex-valued spreading sequences to be used, wherein the Q complex-valued spreading sequences are applied to the Q transmission resources respectively, wherein Q is an integer greater than 1, and the transmission resources comprise time-frequency resources; performing a spreading processing on a data symbol to be sent on a transmission resource of the Q transmission resources by using a complex-valued spreading sequence of the Q complex-valued spreading sequences applied to the transmission resource to generate a symbol sequence; and sending the symbol sequence through the transmission resource, wherein, each element of the complex-valued spreading sequence is a complex number, and values of a real part and an imaginary part of each element are both from an M-element real number set, wherein the M is an integer greater than 2; and wherein the M-element real number set comprises one of: a set formed by M integers within a range of [-(M-1)/2, (M-1)/2], wherein the M is an odd number; a set formed by M odd numbers within a range of [-(M-1), (M-1)], wherein the M is an even number; a set formed by M real numbers obtained through multiplying respectively M integers within a range of [-(M-1)/2, (M-1)/2] by specified coefficient(s), wherein the M is an odd number; and a set formed by M real numbers obtained through multiplying respectively M odd numbers within a range of [-(M-1), (M-1)] by specified coefficient(s), wherein the M is an even number. determining Q transmission resources to be used and Q complex-valued spreading sequences to be used, wherein the Q complex-valued spreading sequences are applied to the Q transmission resources respectively, wherein Q is an integer greater than 1, and the transmission resources comprise time-frequency resources; performing a spreading processing on a data symbol to be sent on a transmission resource of the Q transmission resources by using a complex-valued spreading sequence of the Q complex-valued spreading sequences applied to the transmission resource to generate a symbol sequence; and sending the symbol sequence through the transmission resource, wherein, each element of the complex-valued spreading sequence is a complex number, and values of a real part and an imaginary part of each element are both from an M-element real number set, wherein the M is an integer greater than 2; and wherein the M-element real number set comprises one of: a set formed by M integers within a range of [-(M-1)/2, (M-1)/2], wherein the M is an odd number; a set formed by M odd numbers within a range of [-(M-1), (M-1)], wherein the M is an even number; a set formed by M real numbers obtained through multiplying respectively M integers within a range of [-(M-1)/2, (M-1)/2] by specified coefficient(s), wherein the M is an odd number; and a set formed by M real numbers obtained through multiplying respectively M odd numbers within a range of [-(M-1), (M-1)] by specified coefficient(s), wherein the M is an even number. a set formed by M integers within a range of [-(M-1)/2, (M-1)/2], wherein the M is an odd number; a set formed by M odd numbers within a range of [-(M-1), (M-1)], wherein the M is an even number; a set formed by M real numbers obtained through multiplying respectively M integers within a range of [-(M-1)/2, (M-1)/2] by specified coefficient(s), wherein the M is an odd number; and a set formed by M real numbers obtained through multiplying respectively M odd numbers within a range of [-(M-1), (M-1)] by specified coefficient(s), wherein the M is an even number.