This paper investigates a downlink multiple-input multiple-output (MIMO) multi-carrier code division multiple access (MC-CDMA) system with pilot aided channel estimation (PACE) and iterative channel estimation (ICE) in the receiver. Due to the superposition of different users' spread data signals, zero-valued chips can occur after spreading, which can cause noise enhancement when using data estimates as reference signals in ICE. Hence, we propose a MIMO channel estimation method to overcome the above problem and avoid noise enhancement in ICE. Simulations results for PACE and ICE were computed for a realistic outdoor MIMO channel model. The results show that frame error rates of ICE are smaller than the ones of PACE.
