Digital Connectivity and Low Earth Orbit Satellite: Constellations Opportunities for Asia and the Pacific

Satellite communication plays an important role in the global connectivity ecosystem. It connects rural and remote populations, provides backhaul connectivity to mobile cellular networks, and enables rapid communications for emergency and disaster responses. Low Earth orbit constellations may prove to be transformational to the connectivity landscape based on their global coverage and their suitability for areas not served by fiber optic cable networks. The Asian Development Bank’s developing member countries are well placed to benefit from this expansion of internet connectivity. It will be particularly valuable for small island developing states and landlocked developing countries with limited international bandwidth internet.

Performance Analysis of Millimeter-Wave UAV Swarm Networks under Blockage Effects

Due to their high mobility, unmanned aerial vehicles (UAVs) can offer better connectivity by complement or replace with the existing terrestrial base stations (BSs) in the mobile cellular networks. In particular, introducing UAV and millimeter wave (mmWave) technologies can better support the future wireless networks with requirements of high data rate, low latency, and seamless connectivity. However, it is widely known that mmWave signals are susceptible to blockages because of their poor diffraction. In this context, we consider macro-diversity achieved by the multiple UAV BSs, which are randomly distributed in a spherical swarm. Using the widely used channel model incorporated with the distance-based random blockage effects, which is proposed based on stochastic geometry and random shape theory, we investigate the outage performance of the mmWave UAV swarm network. Further, based on our analysis, we show how to minimize the outage rate by adjusting various system parameters such as the size of the UAV swarm relative to the distance to the receiver.

Design of a New Type of Optical Fiber Infrasound Sensor and Its Usage in Karst Geological Exploration

In this study, the demand of optical fiber (OF) sonic sensor is analyzed, and a composite OF infrasound sensor is proposed aiming at the detection demand of low-frequency infrasound waves in specific occasions. With this sensor, the polymer thin film and the aluminum soil can be combined to form a kind of composite film, the ECF/P interferometer can be formed between the end faces of the ferrule of the OF FC contact, the sensor head of the OF ECF/P infrasound sensor system is fabricated and then packaged. The designed OF infrasound sensor is used in the construction of a wireless sensor network (WSN) for karst geological exploration. The structure of the WSN includes the SimpliciTI communication network protocol, ADF7021 RF transceiver chip, STM32 processor chip, etc. New types of environment from karst can be sampled with this WSN. During the test, the performance of the composite OF infrasound sensor is analyzed at the beginning. The acoustic sensitivity of up to –136.73 dB re 1 V/μPa can be obtained in the low frequency infrasound range (1–20 Hz); the WSN based on the composite OF infrasound sensor has lower power consumption and faster networking speed. In addition, it can realize signal cover in karst areas without public mobile cellular networks, and send the information collected by the sensor to the data center, thus proving the fiber optic sound wave sensor designed in this study is successful and helpful for the geological prospectors to monitor the environment.