NSF Grant 2323189
IMR: MT: AirScope: A Flexible and Programmable Platform for End-to-End Mobile Network Measurements in Rural Environments Using UAVs.
List of personnel
- Principal Investigator: Morteza Hashemi
- Co-Principal Investigators: Shawn Keshmiri and Victor Frost
Overview and Goals
Motivation. The U.S. Federal Communications Commission (FCC) has introduced a procedure allowing cellular users to demonstrate that their carrier’s claims on service quality are inaccurate and that they do not have sufficient cellular service in a particular location. This demonstrates that significant differences exist between the FCC’s data, the claims made by cellular network providers, and users’ actual experiences.
In rural areas, the situation worsens since accurate and at-scale cellular measurements in rural areas are challenging due to various factors. (i) Rural areas have a more dispersed population, which makes it more difficult and expensive for mobile network providers to deploy and maintain network infrastructure, leading to variations and non-uniformity in network performance. (ii) Many mobile network performance tests rely on crowdsourced data to measure network speeds and quality. However, in rural areas, there are fewer people with access to these types of apps, and so the data collected are less representative of the actual network performance in those areas. (iii) The terrain and physical environment in rural areas (e.g., large agricultural fields, hills, etc.) along with large measurement areas make it more challenging for at-scale cellular measurements using the existing manual tools.
Despite the above challenges (e.g., data accuracy, sample size, large measurement areas), there is a pressing need to develop mechanisms for collecting reliable and comprehensive measurement data at scale in rural areas, particularly with the emergence of novel use cases such as precision Ag, remote work, tele-health, online education, etc. This is a technology policy issue that has implications for (i) policymakers and regulators to improve broadband access, quality, and fairness in rural areas, (ii) cellular service providers for network planning and deployment, (iii) researchers to develop connectivity solutions that are tailored for rural areas, and (iv) end-users, such as farmers and schoolchildren who rely on cellular networks for their operations and education.
Using unmanned aerial vehicles (UAVs) to perform programmable and automated data collection will open new possibilities to perform large-scale measurements more efficiently. The overarching goal of this project is to design, build, and publicly release a versatile UAV-based measurement suite (“AirScope”) for radio access network (RAN) and end-to-end network measurements in rural areas.
Goals. There are three major goals in this project:
Goal 1: Developing a Versatile UAV Platform with Cellular Capabilities. In this project, we aim to design and build several vertical take-off and landing (VTOL) UAVs and integrate the LTE/5G modem with the flight controller and the UAV’s on-board processor, such that command and control (C2), telemetry, and payload data are communicated through commercial cellular networks.
Goal 2: Measurement-Aware Algorithmic Development. As the second goal, we aim to design and implement a comprehensive database system that logs any pertinent internal and external measurement data (RAN, end-to-end metrics, GPS data, weather conditions, and UAV telemetry). To enhance the efficiency of the data collection tool, we develop a novel algorithm using Kolmogorov-Arnold representation theorem to estimate the spatio-temporal measurement map based on sparse observation points. We will develop the novel concept of measurement-aware trajectory design and refinement.
Goal 3: Extensive Evaluation Campaign and Large Cellular Dataset Curation. Finally, we test, validate, and refine our tool under a rich set of scenarios in rural areas. Our effort will result in an unprecedented dataset of cellular measurement data that can be used for ML/AI-based and data-driven research projects.
Key Accomplishments
An overall system model for the AirScope measurement platform is shown in the above figure, in which the UAV communicates with the commercial LTE cell tower, and is controlled with a remote automatic flight controller. Measurements are taken between the UAV and AirScope server. Through flight tests at different altitudes (from the ground level up to 400 ft), various RAN and end-to-end performance metrics are collected. Our in-house KU Automatic Flight System (AFS) 5.0, is designed for advanced aerospace applications and uses the powerful, energy-efficient NVIDIA Jetson Orin NX 16GB with a small form factor.
Our cellular measurement campaign has several phases. In the first step, we select the measurement environment and design the flight path. In the second step, the measurement will start and logging software will record time-stamped measurements on RAN metrics, end-to-end network metrics, weather conditions, and UAV flight information, along with GPS data. We will measure these performance metrics for different message types (C2, telemetry, sensory, and payload). In the third step, and upon the completion of the measurement, the pMLTE cellular module is accessed for remote data retrieval. At the end of each measurement, all on-board collected data can be easily transferred to a more permanent data storage using available services (e.g., FTP) provided by the pMLTE and Orin processor.
Major activities. Thus far, we have made significant progress. In particular, we have (1) purchased the required hardware components, (2) developed a 3D printed enclosure for hardware integration with UAVs, (3) developed proof-of-concept communication and data logging software, (4) conducted extensive walking and driving tests to collect LTE measurement data, (5) integrated the pMLTE module with the VTOL UAV, and (6) performed several preliminary flight tests. The second figure shows a summary of these steps as well as flight tests with collected LTE performance metrics using UAV. Therefore, currently, we are able to collect all RAN-related performance metrics from major commercial cellular providers (e.g., Verizon and AT&T).
Ongoing efforts. The development of end-to-end performance measurement is in progress, with the remote server already up and running at the Institute for Information Science (I2S) at KU. However, software development for end-to-end measurement and the experimenter interface is ongoing. This is significantly important as our goal is to develop a “user-friendly” measurement tool that is publicly available and the broader research community can easily use.
Secondly, we aim to upgrade our cellular modem to 5G, as there are significant interests in understanding the 5G coverage and its usability in higher frequency bands. As deployments in mid- and high-bands roll out, investigating 5G performance becomes more important. The AirScope tool is designed with a strong emphasis on modularity, allowing such upgrades of the LTE cellular modem to 5G.
Measurement datasets and tool software/hardware. Please stay tuned as we will release all collected datasets, developed software, and hardware modules here.