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Solid-state light-detection-and-ranging (LiDAR) sensors based on integrated optical phased arrays (OPAs) have shown significant promise to reduce the cost, size, weight, and power consumption associated with LiDAR for autonomous systems. However, these OPA-based LiDAR systems typically operate by rastering a single beam, generating point clouds that constitute a significant amount of data and computational burden in the process. In this paper, we develop and experimentally demonstrate a novel multi-beam solid-state OPA-based LiDAR system capable of detecting and ranging multiple targets simultaneously, passively, and without rastering. Specifically, we develop the devices, subsystems, and system architectures to realize a solid-state frequency-modulated-continuous-wave (FMCW) LiDAR system that leverages a discrete-Fourier-transform star-coupler-based OPA as a receiver and a multi-beam splitter-tree-based OPA as a transmitter. Using this multi-beam LiDAR system, we demonstrate the simultaneous detection and ranging of two targets at two different cross-range positions without rastering. Through this work, we demonstrate a new spatially-adaptive sensing modality for solid-state LiDAR that enables improved spatial awareness and promises to reduce the data deluge associated with LiDAR in autonomous systems.

Objective: Individuals with persistent post-concussive symptoms (PPCS) may present with a myriad of physical symptoms. There is limited research available comparing the presence of examination findings among individuals with PPCS from different age groups., Methods: Retrospective case-control chart review of 481 patients with PPCS and 271 non-trauma controls. Physical assessments were categorized as ocular, cervical, and vestibular/balance. Differences in presentation were compared between PPCS and controls as well as between individuals with PPCS in three age groups: adolescents, young adults, and older adults., Results: All three PPCS groups had more abnormal oculomotor findings than their age-matched counterparts. When comparing PPCS patients from different age groups, no differences were seen in prevalence of abnormal smooth pursuits or saccades; however, adolescents with PPCS had more abnormal cervical findings and a lower prevalence of abnormal NPC, vestibular and balance findings., Conclusion: Patients with PPCS presented with a different constellation of clinical findings based on their age. Adolescents were more likely to demonstrate evidence of cervical injury compared to younger and older adults, and adults were more likely to present with vestibular findings and impaired NPC. Adults with PPCS were more likely to present with abnormal oculomotor findings compared to adults with non-traumatic causes of dizziness.