中文说明：DSI方法基本上是一种改进的SLM方法。另一方面
English Description：
The DSI method is basically a modified SLM method. The additional aspect of the DSI method is to add M-bits dummy sequences to the original sequence in order to reduce the PAPR. Where, the dummy bits are inserted at the end of the data sequence (y). Next, after IFFT, we select the M-DSI sequence having the lowest PAPR.