Spherical Polar Pattern Matching for Star Identification.

Sensors (Basel)

Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209, China.

Published: July 2025


Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

To endow a star sensor with strong robustness, low algorithm complexity, and a small database, this paper proposes an all-sky star identification algorithm based on spherical polar pattern matching. The proposed algorithm consists of three main steps. First, the guide star is rotated to be a polar star, and the polar and azimuth angles of neighboring stars are used as polar pattern elements of the guide star. Then, the relative azimuth histogram is applied to the spherical polar pattern matching, and a star pair after spherical polar pattern matching is identified through angular distance cross-verification. Finally, a reference star image is generated from the identified star pair to complete the matching process of all guide stars in the field of view. The proposed algorithm is verified by simulation experiments. The simulation results show that for a star sensor with a medium field of view (15° × 15°, 1024 × 1024 pixel) and a limiting magnitude of 6.0 Mv, the required database size is 161 KB. When false and missing star spots account for 50% of the guide stars and the star spot extraction error is 1.0 pixel, the average star identification time is 0.35 ms (@i7-4790), and the identification probability is 99.9%. However, when false and missing star spots account for 100% of the guide stars and the star spot extraction error is 5.0 pixel, the average star identification time is less than 2.0 ms, and the identification probability is 97.1%.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC12252525PMC
http://dx.doi.org/10.3390/s25134201DOI Listing

Publication Analysis

Top Keywords

polar pattern
20
spherical polar
16
pattern matching
16
star
16
star identification
16
guide stars
12
matching star
8
star sensor
8
proposed algorithm
8
guide star
8

Similar Publications

Background: Lesbian, gay, bisexual, transgender, queer/questioning, intersex, asexual (LGBTQIA+) researchers and participants frequently encounter hostility in virtual environments, particularly on social media platforms where public commentary on research advertisements can foster stigmatization. Despite a growing body of work on researcher virtual hostility, little empirical research has examined the actual content and emotional tone of public responses to LGBTQIA+-focused research recruitment.

Objective: This study aimed to analyze the thematic patterns and sentiment of social media comments directed at LGBTQIA+ research recruitment advertisements, in order to better understand how virtual stigma is communicated and how it may impact both researchers and potential participants.

View Article and Find Full Text PDF

In this study, using a set of scanning probe microscopy techniques, we investigate the electronic properties of the domain walls in the layered ferroelectric semiconductor of the transition metal oxide dihalide family, NbOI. Although the uniaxial ferroelectricity of NbOI allows only 180° domain walls, the pristine 2D flakes, where polarization is aligned in-plane, typically exhibit a variety of as-grown domain patterns outlined by the electrically neutral and charged domain walls. The electrically biased probing tip can modify the as-grown domain structures.

View Article and Find Full Text PDF

Patchy nanoparticles (NPs) enable directional interactions and dynamic structural transformations, yet controlling polymeric patch formation with high spatial precision remains a significant challenge. Here, a thermally driven approach is presented to forming polystyrene (PS) patches on low-curvature facets of anisotropic gold nanocubes (NCs) using a single polymer component. Heating in DMF above 90 °C triggers selective desorption of PS chains from high-curvature edges and vertices via Au─S bond dissociation, followed by migration and deposition into rounded patches on flat surfaces.

View Article and Find Full Text PDF

Significance: Tumor tissues exhibit contrast with healthy tissue in circular degree of polarization (DOP) images via higher magnitude circular DOP values and increased helicity-flipping. This phenomenon may enable polarimetric tumor detection and surgical/procedural guidance applications.

Aim: Depolarization metrics have been shown to exhibit differential responses to healthy and cancer tissue, whereby tumor tissues tend to induce less depolarization; however, the understanding of this depolarization-based contrast remains limited.

View Article and Find Full Text PDF

Unlabelled: Marinisomatota (formerly recognized as Marinimicrobia, Marine Group A, and SAR406) are ubiquitous and abundant in marine environments, traditionally characterized as heterotrophic microorganisms. However, certain members of Marinisomatota have demonstrated the capacity to harness light for carbon dioxide fixation and the synthesis of organic compounds, thriving in the translucent zone or transitioning between the translucent and aphotic layers. The metabolic strategies driving the shift in trophic behaviors, and the factors influencing these transitions, remain largely unexplored.

View Article and Find Full Text PDF