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.

主权项

1. An apparatus for transmitting and receiving signals in a spectrum shared by first and second transmission systems, said apparatus comprising:
a transmitter:
transmitting a signal of said second transmission system in a first phase of a signal transmission period, when an initial sensing operation of said apparatus indicates that a primary signal of said first transmission system has not been received; and an interference processor:
receiving, in a second phase, a relayed version of said signal transmitted in said first phase of said signal transmission period;canceling interference caused by receipt of said relayed version of said signal transmitted in said first phase of said signal transmission period by removing said signal transmitted in said first phase of said signal transmission period from said received relayed version of said signal transmitted in said first phase of said signal transmission period; and the transmitter:
performing a sensing operation of said primary signal in said second phase of said signal transmission period while canceling out said interference caused by receipt of said relayed version of said signal transmitted in said first phase; andtransmitting another signal in a first phase of a next signal transmission period when said sensing operation indicates that said primary signal has not been received; anddelaying, by a known period of time, transmission of said another signal in said first phase of said next signal transmission period when said sensing operation indicates that said primary signal has been received.