A generalized view on multicarrier CDMA mobile radio systems with joint detection .1.

This communication presents a generalized view on multicarrier code division multiple access (MC-CDMA) concepts for mobile radio applications. A comprehensive introduction to CDMA and the arising multiple access interference (MAI) will be presented. It will be explained why joint detection (JD) is a mandatory prerequisite for hybrid frequency and rime divided code division multiple access (F/T/CDMA) which is a viable basis for third generation mobile radio systems. The benefits of MC-CDMA over other CDMA concepts will be discussed in an illustrative manner and a flexible MC-CDMA concept will be introduced and explained in detail. The signal generation in MC-CDMA will be described in continuous-time and discrete-time form revealing the close relationship between the presented flexible MC-CDMA and the well known joint detection CDMA (JD-CDMA) concept. The discrete-time transmission model which results from the continuous-time representation will be introduced to facilitate digital signal processing. This transmission model takes coherent receiver antenna diversity (CRAD) explicitly into account. Four viable JD techniques suitable for the discussed flexible MC-CDMA concept will be presented. Their structure and mode of operation will be explained in detail and their uplink performance will be studied in a variety of transmission conditions.