Master of Science in Electrical Engineering (MSEE), Wright State University, 2023, Electrical Engineering

Radar cross section (RCS) of electrically large targets can be challenging and expensive to measure. The use of scale models to predict the RCS of such large targets saves time and reduces facility requirements. This study investigates Ka-band (27 to 29 GHz) RCS prediction from scale model measurements at 500 to 750 GHz. Firstly, the coherent quasi-monostatic turntable RCS measurement system is demonstrated. Secondly, three aluminum 18:1 scale dihedrals with surface roughness up to 218 icroinches are measured to investigate how the roughness affects the Ka-band prediction. The measurements are compared to a parametric scattering model for the specular response, and indicate that the models' surface roughness have negligent effect on the RCS prediction.

Committee: Michael A. Saville Ph.D. (Advisor); Yan Zhuang Ph.D. (Committee Member); Elliott R. Brown Ph.D. (Committee Member) Subjects: Electrical Engineering; Electromagnetics; Engineering

Doctor of Philosophy (PhD), Wright State University, 2018, Biomedical Sciences PhD

Proprioceptive circuits provide information regarding limb position and movement status, and are essential to producing correctly executed motor behaviors. Exploring the mechanisms underlying the formation of proprioceptive circuits is therefore critical for understanding neurological disorders with altered motor coordination and for restoring circuits damaged by injury. One important proprioceptive circuit, the stretch reflex circuit, is formed between proprioceptive sensory neurons (PSNs) and motor neurons (MNs) that innervate the same muscle. Progress has been made in understanding the spatial organization of MNs based on their muscle-specific subpopulation identities, which contributes to the specificity of stretch reflex circuit formation. However, whether PSNs share similar properties is underexplored. As PSNs form connections with MNs via highly elaborated axonal terminals (termed arbors), we assessed the spatial and morphological patterns of arbors from PSNs innervating the quadriceps (Quad) and adductor (Add) muscle groups (supplied by Obturator nerve [Obt]). We found that the arbors of Quad and Obt PSNs exhibit muscle-specific morphologies and spatial arrangements consistent with their target MN locations. PSNs also make connections with multiple spinal interneurons, including Renshaw cells (RCs), which are inhibitory interneurons that regulate the output of MNs. In contrast to the stretch reflex circuit, little is known about the organization of PSN contacts on RCs. Therefore, we mapped the connectivity pattern between RCs and PSNs from Quad and Obt afferents. We found that, although some RCs were selectively contacted by afferents from only one nerve, others received convergent input from both nerves. Interestingly, we found RCs with different connectivity patterns appear to be enriched in distinct regions of the ventral cord. During development, PSNs continually experience patterned neural activity. Though the importance of neural activity in rem (open full item for complete abstract)

Committee: David Ladle Ph.D. (Advisor); Mark Rich M.D., Ph.D. (Committee Member); Katherine Excoffon Ph.D. (Committee Member); Lynn Hartzler Ph.D. (Committee Member); Patrick Sonner Ph.D. (Committee Member) Subjects: Neurosciences

Doctor of Philosophy, The Ohio State University, 2017, Electrical and Computer Engineering

Automotive radar is an emerging field of research and development. Technological advancements in this field will improve safety for vehicles, pedestrians, and bicyclists, and enable the development of autonomous vehicles. Many automotive companies have already begun to develop autonomous emergency braking (AEB) to avoid or mitigate pedestrian and bicyclist crashes. However, the effectiveness of such systems needs to be accurately tested using standardized test procedures, which have yet to be agreed upon by the international automobile industry and associated government agencies. European testing standards, such as the Euro New Car Assessment Program (NCAP) AEB and AEB-VRU (vulnerable road user), are currently among the first of these standards, and are used for vehicle and pedestrian targets; with plans to include bicyclist targets in the near future. Such standards allow consumers and government regulatory agencies to assess the effectiveness of a vehicle equipped with an AEB system. Obviously, it is neither practical nor safe to use real targets such as pedestrians, bicyclists, or vehicles to conduct such tests. Therefore, a key element of standardized AEB test protocols is standardized surrogate targets that can produce similar sensor responses as real-life cars, pedestrians, and bicycles. In addition, such standard targets need to withstand repeated impacts from the vehicle under test (VUT), prevent damage to the VUT, and be easily reassembled after impacts. This dissertation establishes the steps for characterization of various targets through measurements, the design of a surrogate bicyclist target, and demonstrates successful hardware-in-the-loop (HIL) emulation of targets for AEB scenarios. To design a surrogate target means that the original target must be accurately characterized. This can be done by first studying the far-field radar cross section (RCS) of the target. Since most AEB test scenarios range from 0 m to 100 m, the RCS measurement in t (open full item for complete abstract)

Committee: Chi-Chih Chen (Advisor); Joel Johnson (Committee Member); Graeme Smith (Committee Member); Ahmet Selamet (Committee Member) Subjects: Automotive Engineering; Electrical Engineering; Electromagnetics

Master of Science (MS), Ohio University, 2008, Electrical Engineering (Engineering and Technology)

Digital Video Broadcasting - Return Channel over Satellite (DVB-RCS) Turbo Codes have become increasingly popular because of their ability to provide an uplink and downlink on the same path. However, the hardware implementation of these codes remains a challenge to the engineers and designers. This research focuses on the implications of quantizing a decoder's input to achieve a significant improvement in the hardware implementation of the decoding architecture. The performance issues related to the quantization have been studied in detail. An approach to achieving performances very close to the floating point methodologies has been presented in the form of an algorithm. Results show that by sacrificing very little performance, cost effective and optimal hardware designs can be obtained.

Committee: Jeffrey C. Dill (Advisor) Subjects: Electrical Engineering