The present invention discloses a channel frequency spreading device for a CDMA system, including: an orthogonal sequence generating module, configured to generate orthogonal sequence sets; a storage module, connected to the orthogonal sequence generating module, and configured to store the orthogonal sequence sets; a control module, connected to the storage module, and configured to read available orthogonal sequences in the orthogonal sequence sets when receiving a user request control signal; and a channel machine, connected to the control module, and configured to receive user request data, and perform frequency spreading on the user request data according to the available orthogonal sequences and then output. The channel frequency spreading device for a CDMA system can improve the number of the sequences allocated by the cell, and solve the problem that the excessive users cannot communicate normally.

A method for converting source data to a channel-modulated signal having a plurality of pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station uses at least one channel, includes the steps of: a) encoding the source data to generate at least one data part and a control part; b) generating at least one spreading code to be allocated to the channel, wherein each spreading code is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so that two consecutive pairs of the I and Q data are correspondent to two points located on same point or symmetrical with respect to a zero point on a phase domain; and c) spreading the control part and the data part by using the spreading code, to thereby generate the channel-modulated signal.

A method for converting source data to a channel-modulated signal having a plurality of pairs of in-phase (I) and quadrature-phase (Q) data in a mobile station, wherein the mobile station uses at least one channel, includes the steps of: a) encoding the source data to generate at least one data part and a control part; b) generating at least one spreading code to be allocated to the channel, wherein each spreading code is selected on the basis of a data rate of the data part and the control part and spreading codes are selected so that two consecutive pairs of the I and Q data are correspondent to two points located on same point or symmetrical with respect to a zero point on a phase domain; and c) spreading the control part and the data part by using the spreading code, to thereby generate the channel-modulated signal.

An interference canceller comprises a composite interference vector (CIV) generator configured to produce a CIV by combining soft and/or hard estimates of interference, an interference-cancelling operator configured for generating a soft projection operator, and a soft-projection canceller configured for performing a soft projection of the received baseband signal to output an interference-cancelled signal. Weights used in the soft-projection operator are selected to maximize a post-processing SINR.

An interference canceller comprises a composite interference vector (CIV) generator configured to produce a CIV by combining soft and/or hard estimates of interference, an interference-cancelling operator configured for generating a soft projection operator, and a soft-projection canceller configured for performing a soft projection of the received baseband signal to output an interference-cancelled signal. Weights used in the soft-projection operator are selected to maximize a post-processing SINR.

A wireless communication may receive a composite signal that includes data symbols, a code division multiplexing (CDM) pilot sequence that is spread with a first channelization code, and a time division multiplexing (TDM) pilot sequence including a cyclic prefix where the TDM pilot sequence is spread with a second channelization code. The composite signal may be received within a designated time region such that the CDM pilot sequence has non-cyclic properties over the designated time region. The composite signal may be descrambled with a non-cyclic scrambling code.

Methods and a system are described for generating a waveform for transmitting data over a channel divided into a plurality of adjacent frequency subcarriers. One method includes receiving a plurality of data bits, each destined for a different receiver of a plurality of receivers. For each received data bit, the method further includes coding the data bit using a unique spreading code of a first set of spreading codes to generate a corresponding group of multiple copies of a data symbol. Additionally, the groups of data symbols, corresponding to the plurality of data bits, are interleaved to generate a sequence of interleaved data symbols, and the sequence of interleaved data symbols is mapped to the plurality of adjacent frequency subcarriers to generate a waveform symbol.

Methods and a system are described for generating a waveform for transmitting data over a channel divided into a plurality of adjacent frequency subcarriers. One method includes receiving a plurality of data bits, each destined for a different receiver of a plurality of receivers. For each received data bit, the method further includes coding the data bit using a unique spreading code of a first set of spreading codes to generate a corresponding group of multiple copies of a data symbol. Additionally, the groups of data symbols, corresponding to the plurality of data bits, are interleaved to generate a sequence of interleaved data symbols, and the sequence of interleaved data symbols is mapped to the plurality of adjacent frequency subcarriers to generate a waveform symbol.

A composite signal may be generated with code division multiplexing (CDM) and time division multiplexing (TDM) pilots. A first pilot sequence may be a CDM pilot sequence. A second pilot sequence may have TDM pilot sequences including a cyclic prefix. The composite signal may have a cyclic prefix time domain portion based on the cyclic prefix and a base portion of the composite signal.

Methods and network nodes of a wireless telecommunications system are disclosed. One method of controlling transmissions with a base station of a wireless telecommunications system comprises the steps of: determining a set of neighboring base stations, each base station in the set of neighboring base stations utilizing an identical carrier and scrambling code to support transmissions with that base station; and allocating base stations in the set of neighboring base stations different spreading codes for transmissions with those base stations. By allocating each base station in the set of base stations sharing the same carrier and scrambling code different spreading codes, interference in transmissions between the base stations can be controlled.