Improved Almost Blank Subframe Technology Based On Interference Suppression

Abstract

Almost blank subframe (ABS) is an effective method to eliminate interference in heterogeneous networks, but the existence of ABS will cause the degradation of the communication performance of the macro cell. To tackle this issue, an improved ABS technology based on interference suppression was proposed in this paper. Firstly, the channel parameters are estimated in the ABS frame and sent back to the micro base station (BS). Secondly, the micro BS uses the estimated parameters and the synchronized digital signal of the macro BS to calculate the pre-processed digital signal. Finally, the predistortion part of the signal from the micro BS and the signal from the macro BS cancel each other out at the terminal. The proposed method can alleviate the interference of the macro BS to the edge users of the small cell, and significantly reduce the proportion of ABS frames in the macro BS, thereby improving the communication performance of the macro cell.