They are acoustic front end processing, canonical correlation based on compensation method, and increase of poles method.

即语音前端声学处理法、正则相关分析的谱变换补偿方法和同模极点增加法。

youdao

We can categorize many state-of-the-art environment compensation approaches into two classes: the front-end and the back-end (acoustic model) processing approaches.

目前的一些鲁棒性环境补偿方法具体可分为两大类：前端处理方法和后端（声学模型）处理方法。

youdao