No abstract

Diffusion-based molecular communication (DBMC) has emerged as a promising communication option, particularly for biomedical and healthcare applications. Although, numerous studies have been conducted to evaluate and analyse DBMC system, investigation on DBMC through multilayer channels has had less attention. In this paper, a closed-form expression is derived for the mean molecular concentration over an n-layer channel. An averaged diffusion coefficient for thin, dissimilar and multilayer propagation channels is determined through the addition of a diffusion resistance for each medium analogously to the sum of series resistors in circuit theory. The channel characteristics such as impulse response, time delay and attenuation are analytically obtained using amplitude detection technique. The effects of layer thickness and the distance between a transmitter nanomachine and a receiver nanomachine on the channel time delay and channel attenuation under the pulse modulation scheme are evaluated and discussed. The results show that increasing the diffusion coefficient leads to time delay decrements; however, the channel attenuation remains unchanged. Moreover, lengthening the transmission distance increases the time delay and decreases the channel attenuation.

Plants, flowers and crops are living things around us that makes our earth more productive and beautiful. In order to growth healthy, they need water, light and nutrition from the soil in order to effect cleaning air naturally and produce oxygen to the world. Therefore, a technology that manage to brilliantly control plants watering rate according to its soil moisture and user requirement is proposed in this paper. The developed system included an Internet of Things (IoT) in Wireless Sensor Network (WSN) environment where it manages and monitors the irrigation system either manually or automatically, depending on the user requirement. This proposed system applied Arduino technology and NRF24L01 as the microprocessor and transceiver for the communication channel, respectively. Smart agriculture and smart lifestyle can be developed by implementing this technology for the future work. It will save the budget for hiring employees and prevent from water wastage in daily necessities.

In nanoscale communication, diffusion-based molecular communication (DBMC) in which information is encoded into molecule patterns by a transmitter nanomachine, has emerged as a promising communication system, particularly for biomedical and healthcare applications. Although, numerous studies have been conducted to evaluate and analyze DBMC systems, investigation on DBMC system through a multilayer channel has received less attention. The aims of this paper are to formulate channel characteristics and to evaluate the performance of multilayer DBMC channel in terms of delay spread and capacity. In this paper, the propagation of molecules over an n- layer channel is assumed to follow the Brownian motion and subjected to Fick's law of diffusion. Fourier transform is used to convert time to frequency domain functions. Besides, the multilayer channel is considered as a linear and deterministic channel. For the performance evaluation, the air-water-blood plasma medium representing the simplified multilayer diffusion model in the respiratory system was chosen. It was found that a high channel capacity can be achieved with wide transmission bandwidth, short transmission distance, and high averaged transmitted power. In addition, the findings showed that channel delay spread increases as both the transmission distance, and the pulse duration increased. By setting the symbol duration greater than the pulse duration or delay spread, an inter-symbol interference problem due to previous molecules transmission can be mitigated. These findings can be used as a guide in the development and fabrication of future artificial nanocommunication and nanonetworks systems involving multilayer transmission medium.