DFE convergence for interference cancellation in spread spectrum multiple access systems

A fractionally spaced decision feedback equalizer (DFE) is proposed for code division multiple access (CDMA) in an interference-dominated environment. This system assumes no knowledge of the interferers´ spreading codes. The calculation of optimum receiver taps shows good improvement in the capacity of the proposed system over others. The DFE receiver is simulated in a multiuser multipath environment. Performance results show the expected convergence of the DFE, with and without knowledge of the desired user´s spreading code. Results also show the effect of sudden birth and death of interferers in the system. The bit error rate of the simulated DFE system is presented