Outage Probability of Multi-code Ds-cdma with Linear Interference Suppression*
نویسندگان
چکیده
We examine the outage probability of a multi-code DSCDMA system with Minimum Mean Squared Error (MMSE) linear interfenxce suppression. Multi-code DS-CDMA allows different information mtes by varying the number of spreading codes assigned to each user. Power control is used to achieve a set of taryet Signal-to-Inter ference-plus-Noise Ratios (SINRS), and an outage occurs if a user must incnmse the transmitted power above a rn~”mum power limit. To compute the outage probability, we derive an accumte approximation for the variance of received SINR over the user population assuming MMSE detection with short spreading co&s. Outage probability is then shown as a fwnction of the number of codes assigned to each user. For a jixed outage probability, our results show that a multi-code scheme can provide approximately .2?dB gain in SINR relative to the corresponding single-code (vam”able processing gain) scheme.
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