Link scheduling schemes with on-off interference map for device-to-device communications

New distributed link scheduling schemes based on a recently proposed device-to-device (D2D) communication technology, FlashLinQ are studied. FlashLinQ is an orthogonal frequency division multiplexing-based synchronous D2D communication system, which achieves a high data rate at longer communication ranges over a licensed spectrum. In this method, some links are selected for data traffic for efficient frequency reuse to avoid interference in D2D links. Where every link is assigned a scheduling priority, so in TX (transmitter) and RX (receiver) yielding, the links which are highly interfered by higher priority links give up communication. However, this technique causes inefficiency in the resource reuse from the cascade yielding problem because link scheduling is performed individually by its RX and TX nodes. To deal with this problem, the authors propose two new link scheduling schemes based on a binary matrix called on-off interference map (I-Map), which indicates strong interference between links. In these schemes, each TX generates a binary I-Map matrix with the collective information from TX and RX blocks. With the common I-Map matrix that displays inter-link interference between D2D links, the proposed schemes achieve better performance as compared to the conventional distributed FlashLinQ scheduling scheme.