On Channel Estimation for Layered Space-Time Block Spread CDMA Systems

This paper proposes three different channel estimation techniques for layered space-time block spread CDMA (LST BS-CDMA) systems, using different pilot patterns. The first technique applies the normal channel estimation method for VBLAST systems on each subcarrier. The second technique constructs time-domain sequences that give a set of nulls at predefined frequency and interpolates those nulled tones to obtain the full frequency response of the channel. The third technique improves on the second technique and eliminates the need for knowledge of the channel delay spread. The LST BS-CDMA system is simulated and its performance is compared when the three different channel estimation technique is used