Improved Multi-Cell Joint Channel Estimation for TD-SCDMA Downlink

In the TD-SCDMA system, joint detection (JD) is employed for data detection and it can effectively cancel out the intra-cell interference. To further improve the system performance, multi-cell JD and inter-cell interference cancellation (IIC) have been proposed to combat the inter-cell interference. However, all the previous works only considered single cell joint channel estimation (JCE), which can not provide sufficient channel estimation accuracy for each cell, especially when the interference from other cells is serious. In this paper, a multi-cell JCE method is proposed, which can simultaneously estimate the channel impulse responses (CIRs) for both the reference cell and adjacent cells with high accuracy. Our simulation results show that the proposed JCE can significantly improve the channel estimation accuracy for all considered cells, and the combination with multi-cell JD yields better system performance compared with the conventional methods.