Signal propagation techniques for wireless underground communication networks

2016 25th International Conference on Computer Communication and Networks (ICCCN)

2016

Self Cite

Abstract-Unique interactions between soil and communication components in wireless underground communications necessitate revisiting fundamental communication concepts from a different perspective. In this paper, capacity profile of wireless underground (UG) channel for multi-carrier transmission techniques is analyzed based on empirical antenna return loss and channel frequency response models in different soil types and moisture values. It is shown that data rates in excess of 124 Mbps are possible for distances up to 12 m. For shorter distances and lower soil moisture conditions, data rates of 362 Mbps can be achieved. It is also shown that due to soil moisture variations, UG channel experiences significant variations in antenna bandwidth and coherence bandwidth, which demands dynamic subcarrier operation. Theoretical analysis based on this empirical data show that by adaption to soil moisture variations, 180% improvement in channel capacity is possible when soil moisture decreases. It is shown that compared to a fixed bandwidth system; soilbased, system and sub-carrier bandwidth adaptation leads to capacity gains of 56%-136%. The analysis is based on indoor and outdoor experiments with more than 1, 500 measurements taken over a period of 10 months. These semi-empirical capacity results provide further evidence on the potential of underground channel as a viable media for high data rate communication and highlight potential improvements in this area.

Section: Introductionmentioning

confidence: 99%

Impacts of Soil Type and Moisture on the Capacity of Multi-Carrier Modulation in Internet of Underground Things

Salam

2016 25th International Conference on Computer Communication and Networks (ICCCN)

2016

Self Cite

“…As a natural extension to the well-established wireless sensor network (WSN) paradigm [1], WUSNs are envisioned to provide underground monitoring capabilities in the fields of intelligent irrigation, environment monitoring, border patrol, and assisted navigation. Despite their potential advantages, however, the realization of WUSNs is challenging due to the significant and direct impact of soil characteristics and its dynamics on communication [3], [10]. More specifically, the changes in temperature, weather, soil moisture, soil composition, and depth directly impact the connectivity and communication success in underground settings.…”

Section: Introductionmentioning

confidence: 99%

Communication with Aboveground Devices in Wireless Underground Sensor Networks: An Empirical Study

Silva

2010 IEEE International Conference on Communications

2010

Abstract-Wireless Underground Sensor Networks (WUSNs) consist of wirelessly connected underground sensor nodes that communicate untethered through soil. WUSNs have the potential to impact a wide variety of novel applications including intelligent irrigation, environment monitoring, border patrol, and assisted navigation. Although its deployment is mainly based on underground sensor nodes, a WUSN still requires aboveground devices for data retrieval, management, and relay functionalities. Therefore, the characterization of the bi-directional communication between a buried node and an aboveground device is essential for the realization of WUSNs. In this work, empirical evaluations of underground-to-aboveground (UG2AG) and aboveground-to-underground (AG2UG) communication are presented. More specifically, testbed experiments have been conducted with commodity sensor motes in a real-life agricultural field. The results highlight the asymmetry between UG2AG and AG2UG communication for different burial depths. To combat the adverse effects of the change in wavelength in soil, an ultra wideband antenna scheme is deployed, which increases the communication range by more than 350% compared to the original antennas. The results also reveal that a 21% increase in the soil moisture decreases the communication range by more than 70%. To the best of our knowledge, this is the first empirical study that highlights the effects of the antenna design, burial depth, and soil moisture on both UG2AG and AG2UG communication performance. These results have a significant impact on the development of multi-hop networking protocols for WUSNs.

“…Then, the transmission ranges can be derived based on the path loss. Since the wireless communications in sands can be viewed as a special case of the underground communications [1], the following channel analysis is based on our previous analysis on the wireless underground channel characteristics [2], [14].…”

Section: Network Architecture and Channel Modelsmentioning

confidence: 99%

“…In (3) and (4), the sand path loss L sand and air path loss L AA can be derived from (2) and (1) can be found in [2], [14], which are functions of the sand dielectric properties, the burial depth of sensor, the distance between the transceivers, and the antenna height of the sensors.…”

Section: Sand-to-air Channel and Air-to-sand Channelmentioning

confidence: 99%

Topology Analysis of Wireless Sensor Networks for Sandstorm Monitoring

Wang

Sun

2011 IEEE International Conference on Communications (ICC)

et al. 2011

Abstract-Sandstorms are serious natural disasters, which are commonly seen in the Middle East, Northern Africa, and Northern China.In these regions, sandstorms have caused massive damages to the natural environment, national economy, and human health. To avoid such damages, it is necessary to effectively monitor the origin and development of sandstorms. To this end, wireless sensor networks (WSNs) can be deployed in the regions where sandstorms generally originate so that sensor nodes can collaboratively perform sandstorm monitoring and rapidly convey the observations to remote administration center. Despite the potential advantages, the deployment of WSNs in the vicinity of sandstorms faces many unique challenges, such as the temporally buried sensors and increased path loss during sandstorms. Consequently, the WSNs may experience frequent disconnections during the sandstorms. This further leads to dynamically changing topology. In this paper, a topology analysis of the WSNs for sandstorm monitoring is performed. Four types of channels a sensor can utilize during sandstorms are analyzed, which include air-to-air channel, air-to-sand channel, sand-to-air channel, and sand-to-sand channel. Based on the channel model solutions, a percolation-based connectivity analysis is performed. It is shown that if the sensors are buried in low depth, allowing sensor to use multiple types of channels improves network connectivity. Accordingly, much smaller sensor density is required compared to the case, where only terrestrial air channels are used. Through this topology analysis a WSN architecture can be deployed for very efficient sandstorm monitoring.