A Cross-Layer Neighbor-Discovery Algorithm for Directional 60-GHz Networks

Directional antennas are preferred for efficient wireless communications in the 60-GHz spectrum. Recent efforts to adapt high-data-rate medium access control (MAC) protocols from standards that are designed for operation in the lower frequency bands face challenges in acquiring the location of nearby devices in a network. In this paper, we propose a cross-layer neighbor-discovery algorithm for directional 60-GHz networks to assist the MAC layer in efficiently using the directional antennas. We utilize linear and circular polarization and their different responses to reflection to synchronize the transmitter and the receiver. This difference in response is used to determine if there is a direct path between the transmitter and the receiver. Based on this knowledge, the direction of the neighboring devices is determined through a cyclic scanning. The proposed algorithm is analyzed based on the usage models defined in the standard for 60-GHz networks.