Channel Modeling and Capacity Analysis for Electromagnetic Wireless Nanonetworks in the Terahertz Band

Abstract

Abstract-Nanotechnologies promise new solutions for several applications in the biomedical, industrial and military fields. At the nanoscale, a nanomachine is considered as the most basic functional unit which is able to perform very simple tasks. Communication among nanomachines will allow them to accomplish more complex functions in a distributed manner. In this paper, the state of the art in molecular electronics is reviewed to motivate the study of the Terahertz Band (0.1-10.0 THz) for electromagnetic (EM) communication among nanodevices. A new propagation model for EM communications in the Terahertz Band is developed based on radiative transfer theory and in light of molecular absorption. This model accounts for the total path loss and the molecular absorption noise that a wave in the Terahertz Band suffers when propagating over very short distances. Finally, the channel capacity of the Terahertz Band is investigated by using this model for different power allocation schemes, including a scheme based on the transmission of femtosecond-long pulses. The results show that for very short transmission distances, in the order of several tens of millimeters, the Terahertz channel supports very large bit-rates, up to few terabits per second, which enables a radically different communication paradigm for nanonetworks.

Parameter study and characterization of wireless nanonetworks through simulation

“…This model takes into account the number of concurrent transmissions along with the distance from the sender. The path-loss and noise in the Terahertz Band are computed by using models introduced in [7], [1]. A standard medium with 10% of water vapor is considered.…”

“…When the reception of a packet ends, a global factor for this packet is computed proportionally from the factors of its individual periods. For each period (computed from a couple of consecutive pivots), the information rate in bit per symbol is extracted from the statistical MATLAB model of the network capacity done by Jornet and Akyildiz (cf [1] and [4]). This bit information rate is then used to compute the SCORE of the message receiving which is the average of the information rate weighted by period lengths relatively to the whole message length.…”

“…Messages having high scores have better chances to be received whereas messages having low scores are likely to be lost. The information rate in bits per symbol will change as explained in [1] depending on the number of nodes contained in the group of sender catoms. We configured this MATLAB model for an environment compounded of air with 10% of moisture.…”

“…There have been analytical work proposed for defining and characterizing this new type of communication channel [1] which has led to the definition of a pulse-based communication scheme named Time-Spread OnOff Keying (TS-OOK) [2]. We have proposed a simulator called Vouivre [3], [4] which is able to simulate an EM wireless nanonetwork.…”

Cooperative signal amplification for molecular communication in nanonetworks

“…Traditional wireless electromagnetic communication, by means of graphene-based nano-antennas, has been proposed to address this issue [6,39,66]. These techniques are expected to produce ultra-high frequency radiation (in the THz range [38]), offering low propagation delays and high bandwidth. However, biomedical applications (and particularly intra-body networks) usually require the use of biocompatible and non-invasive solutions.…”