這是羅技網站上的文章，大概新出的都是RF的了，因為我的接收器被擋到還是不影響說！羅技的東西我覺得還不錯用，但就是貴了點！

Advanced Digital Radio Technology ?All of Logitech´s cordless peripherals are based on proven proprietary digital radio technology. This ensures reliable performance within a six-foot radius of the receiver with no line-of-sight requirement. The receiver can be set off the desk or even behind the computer without affecting performance. For the cordless desktop combinations, ?keyboard and mouse ?one single receiver handles both the mouse and the keyboard.The latest generation of radio technology includes multi-channel RF with encryption to protect the privacy of the data transmitted between the keyboard and the receiver. In addition Logitech´s cordless devices utilize a 12-bit digital secure ID code that enables multiple cordless devices to operate in close proximity without risk of interference.