Distributed Coordination of Aerial Swarms for High-Gain Wireless Transmission
Abstract
Current and future wireless applications, including sensing, communications, and high-power transmission, have driven the need for continual increases in transmitted signal gain. However, the ability to achieve high-gain wireless transmission of microwave signals is restricted by the traditional platform-centric model used to develop wireless systems, where single, large platformsare limited by aperture size, device power handling and efficiency, and heat dissipation, among other factors. Achieving increases in signal gain under the current platform-centric model requires redesigns of devices, apertures, or entire systems, an approach that is not only costly but timeconsuming. To overcome these platform-centric challenges, we propose a novel approach to highgain microwave sig particular, coordinating separate wireless systems to create a coherent distributed phased array can yield dramatic system-level gains that cannot feasibly be achieved with a single platform, or even with non-coherent signal coordination on multiple platforms. These benefits include transmit power gains proportional to the number of platforms squared, significant spatial diversity affording robustness to interference and failures, and the ability to directly scale capabilities by simply adding or removing nodes in the array. The ultimate level of flexibility is achieved in an open-loop array, where the nodes self-align without using feedback from the target location. Whereas closed-loop distributed arrays are possible with signal inputs from the target, such approaches are limited in that the array can only direct signals back to the point of the emanating signal. In contrast, open-loop distributed phased arrays can arbitrarily steer beams to any desired angle. Achieving coherent transmission in distributed arrays requires coordination of the spatio-electrical states of the elements in the array; our group has pioneered efforts in developing technologies for high-accuracy coordination for distributed beamforming in small arrays of 2-4 platforms. We have previously led efforts developing and demonstrating critical technologies enabling fully open-loop coherent distributed transmission, proving the feasibility of achieving and maintaining sufficient phase stability between separate platforms. In prior efforts, a high-accuracy microwave ranging technique using a novel spectrally sparse waveform achieved sub-mm range accuracy and was used to experimentally demonstrate the first open-loop coherent distributed transmission. Other efforts developed a novel one-way wireless frequency locking approach, which was used to demonstrate the first fully technology to achieve distributed phase coherence with small array sizes has been largely proven.In this effort, we will develop novel coordination techniques for high-gain transmission from swarms of hundreds of nodes and evaluate the possibilities of achieving high-gain signal transmission using existing commercial off-the-shelf (COTS) microwave technologies. In particular, we will investigate new techniques for the coordination of large arrays using algorithms based on physical-layer coordination of array element location, frequency, phase, and time. We will assess the feasibility of achieving high-power transmission under realistic system-level constraints, such as coordination errors, noise, array motion, amplifier efficiencies, and beamsteering errors, among others. The results of this effort will inform future high-gain microwave transmission concepts and identify any technology areas for future development toachieve greater capabilities than COTS technologies can provide.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 31, 2020
- Source ID
- N000142012389
Entities
People
- Jeffrey A. Nanzer
Organizations
- Michigan State University
- Office of Naval Research
- United States Navy