Methods, systems, and apparatuses, and combinations and sub-combinations thereof, for down-converting and up-converting an electromagnetic (EM) signal are described herein. Briefly stated, in embodiments the invention operates by receiving an EM signal and recursively operating on approximate half cycles...http://www.google.de/patents/US6813485?utm_source=gb-gplus-sharePatent US6813485 - Method and system for down-converting and up-converting an electromagnetic signal, and transforms for same
