Patent ID: 8284653

Claim:
A user signal transmitting method in an Orthogonal Frequency-Division Multiple Access (OFDMA) system, wherein the OFDMA system comprises multiple terminals and multiple Base Transceiver Stations (BTSs), a user communicates with the (BTSs) via the terminals, and in an OFDMA access manner, a radio resource is divided into multiple two-dimensional time-frequency grids, and wherein all the two-dimensional time-frequency grids of each timeslot are divided into multiple sub-channels, in which each sub-channel comprises N f sub-carriers overlapping in time, where N f ≧4, and in the N f sub-carriers comprised in each sub-channel, a maximum value of a frequency interval between adjacent sub-carriers is three times or more than three times of a minimum value of the frequency interval between the adjacent sub-carriers; and, when any one of the terminals and BTSs acts as a transmitter used for transmitting a user message of the user, the method comprises: generating a modulating signal of the user based on the user message to be sent; mapping the modulating signal of the user to a two-dimensional time-frequency grid set allocated by a network side to the user, to generate a frequency-domain signal of the user, wherein the two-dimensional time-frequency grid set is a union set of one or more sub-channels, in which a quantity of the one or more sub-channel is determined by a size of the user message, and a time-frequency position of the sub-channel is selected according to a predetermined rule; and, performing Inverse Fast Fourier Transform on the frequency-domain signal of the user to generate a time-domain signal of the user, and transmitting the time-domain signal.