Defining a sound shift operator for signals existing on a certain graphical structure, similar to the well-defined shift operator in classical signal processing, is a crucial problem in graph signal processing. graph shift operator. We define a unique shift operator that satisfies all properties the shift operator as in the classical signal processing,… (More)
We propose a resource sharing scheme between a primary pair (which owns the spectrum resources) and a secondary pair (which owns a relay infrastructure) in a collaborative manner. The secondary network allows the primary pair to use the relays in order to establish a bidirectional communication between its transceivers. In exchange for this cooperation, the… (More)
Designing an efficient scheme in physical layer enables cognitive radio (CR) users to efficiently utilize resources dedicated to primary users (PUs). In this paper in order to maximize the SU's throughput, the SU's transceivers beamforming is designed through new model considering the presence of the PU's transmitter. Since presence of primary transmitter… (More)
This paper has been withdrawn by the author due to a crucial problem in Lemma 3. This equation must be changed.