Sensing and communication protocols for shared spectrum usage in a radio cognitive relay system

摘要

The present invention relates to a method, an apparatus and a computer program product for sensing and communicating in transmission systems with shared spectrum usage, which may comprise e.g. a cognitive relay system. The communication between a transmitter and a receiver occurs in two transmission phases via the assistance of a relay. Sensing is performed at the transmitter during the second transmission phase, thus overcoming the need for dedicated slots for sensing.