Interference calculations for MC-SSMA systems in mobile communications

The other-user interference of a multi-carrier spread-spectrum multiple-access system applying conventional detection is considered. The investigations refer to the synchronous uplink, i.e. the synchronous transmission from the mobile stations to the base station in a mobile communications system. Under the assumption of independent Rayleigh fading the probability density function of the interference signal is calculated analytically and it is shown that the resulting probability density function can be well approximated by a Gaussian distribution. Moreover, refering to the bit error rate formula for the single-user case a closed-form expression for the bit error rate in the case of other-user interference is derived using the Gaussian approximation method. The analytical results are validated by Monte-Carlo simulations