Link Discovery Extension to ns-3's Terahertz Communication Module

The next generation wireless access networks are envisaged to use Terahertz (THz) frequencies to achieve extremely high data rates on the order of Terabits per second. These high frequency waves experience intense path loss and are therefore limited to very short transmission distances. Enhancing transmission range for THz waves requires a shift from omnidirectional antennas to directional antennas for sender as well as receiver nodes. Signal power can then be used to achieve longer propagation distance albeit in a single direction which creates the deafness problem. These changes require the redesign of link access mechanisms to be able to work with directional antennas. In this paper we extend ns-3's Terahertz communication module to support link discovery in an infrastructure mode THz network. While the discovery protocol is implemented at the MAC layer, relevant modifications in the Antenna and Channel classes were required to allow the operation of the protocol. The designed link access mechanism is based on an exhaustive search approach. We describe the implementation in detail and present the discovery performance when different beamwidths and modulation schemes are employed.