How to get the Same File Name in Sender & Receiver FTP channel?

Hi,

   we are on PI 7.11 with SP8. We have a scenario wherein we are suppose to pick-up some file from SAP application server & FTP those files on to some other application server. For picking-up files i have used sender FTP Channel & to put a files i have used Receiver FTP channel.

The scenario is working fine but it is changing the file name while putting it on target directory.

   We want while putting the files it should have the same name as the source file.

Can anybody tell me how to do this? do we nned to use SFTP channel?

pl. explain me in detailed.

Regards,

Umesh