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CubeSats are a class of miniaturized satellites that have become increasingly popular in academia and among hobbyists due to their short development time and low fabrication cost. Their compact size, lightweight characteristics, and ability to form a swarm enables them to communicate directly with one another to inspire new ideas on space exploration, space-based measurements, and implementation of the latest technology. CubeSat missions require specific antenna designs in order to achieve optimal performance and ensure mission success. Over the past two decades, a plethora of antenna designs have been proposed and implemented on CubeSat missions. Several challenges arise when designing CubeSat antennas such as gain, polarization, frequency selection, pointing accuracy, coverage, and deployment mechanisms. While these challenges are strongly related to the restrictions posed by the CubeSat standards, recently, researchers have turned their attention from the reliable and proven whip antenna to more sophisticated antenna designs such as antenna arrays to allow for higher gain and reconfigurable and steerable radiation patterns. This paper provides a comprehensive survey of the antennas used in 120 CubeSat missions from 2003 to 2022 as well as a collection of single-element antennas and antenna arrays that have been proposed in the literature. In addition, we propose a pictorial representation of how to select an antenna for different types of CubeSat missions. To this end, this paper aims is to serve both as an introductory guide on CubeSats antennas for CubeSat enthusiasts and a state of the art for CubeSat designers in this ever-growing field.

The Present CubeSat project success rate may deter nonprofit organizations from beginning new projects, especially for first-time creators. However, since the electronic components of a CubeSat are intended to be very power-efficient and tightly placed, its size and electrical characteristics provide a more difficult limitation. The CubeSat antennas are key parts that will need to be carefully designed since they need to be tiny, light, and deployable for bigger antennas. This study provides an extensive overview of the key characteristics of metasurface-based antennas with an emphasis on their effectiveness in CubeSat communication systems. This research work initially introduces metasurface antennas and examines how well-suited they are geometrically for Various frequency bands for CubeSat spacecraft. Furthermore, a detailed analysis of these metasurface antennas' radiating capabilities is conducted in accordance with the CubeSat configuration, links, and Orbits. Additionally, over thirty X-band metasurface-based antennas are fully evaluated in terms of their suitability for CubeSats. The use of specifically designed metasurfaces has resulted in a notable increase in CubeSat antenna performance. This paper offers an emerging approach for researchers to advance the usage of metasurface-based antennas in CubeSat missions such as UMS5-Ribat and UMS-EOSAT CubeSats of University Mohammed V in Rabat.

The proliferation of CubeSats in Earth orbit has accelerated dramatically in recent years, with projections indicating continued growth in the coming decades. This review examines the evolution of CubeSat applications, from basic technology demonstrations to complex mission capabilities, including Earth observation, telecommunications, astronomical research, biological experimentation, and deep-space exploration. A notable shift has occurred over the past fifteen years, with CubeSats transitioning from standalone platforms to integrated nodes within larger constellations, particularly for Earth observation and telecommunications applications. We analyze the key enabling factors behind the CubeSat revolution, including decreased launch costs, miniaturized electronics, standardized components, and institutional support frameworks. Through the examination of significant past, current, and planned missions, this paper provides a comprehensive overview of CubeSat capabilities across diverse application domains. The review highlights how these miniaturized satellite platforms are democratizing access to space while enabling innovative scientific and commercial applications previously restricted to larger spacecraft.

Recent deployments of CubeSat imagers by companies such as Planet may advance hydrological remote sensing by providing an unprecedented combination of high temporal and high spatial resolution imagery at the global scale. With approximately 170 CubeSats orbiting at full operational capacity, the Planet CubeSat constellation currently offers an average revisit time of <1 day for the Arctic and near-daily revisit time globally at 3 m spatial resolution. Such data have numerous potential applications for water resource monitoring, hydrologic modeling and hydrologic research. Here we evaluate Planet CubeSat imaging capabilities and potential scientific utility for surface water studies in the Yukon Flats, a large sub-Arctic wetland in north central Alaska. We find that surface water areas delineated from Planet imagery have a normalized root mean square error (NRMSE) of <11% and geolocation accuracy of <10 m as compared with manual delineations from high resolution (0.3–0.5 m) WorldView-2/3 panchromatic satellite imagery. For a 625 km2 subarea of the Yukon Flats, our time series analysis reveals that roughly one quarter of 268 lakes analyzed responded to changes in Yukon River discharge over the period 23 June–1 October 2016, one half steadily contracted, and one quarter remained unchanged. The spatial pattern of observed lake changes is heterogeneous. While connections to Yukon River control the hydrologically connected lakes, the behavior of other lakes is complex, likely driven by a combination of intricate flow paths, underlying geology and permafrost. Limitations of Planet CubeSat imagery include a lack of an automated cloud mask, geolocation inaccuracies, and inconsistent radiometric calibration across multiple platforms. Although these challenges must be addressed before Planet CubeSat imagery can achieve its full potential for large-scale hydrologic research, we conclude that CubeSat imagery offers a powerful new tool for the study and monitoring of dynamic surface water bodies.

In order to satisfy the needs of the smallest cube satellite unit with nearly insignificant air drag altitude, we construct, reduce in size, and optimize an innovative single-layer metasurface antenna in this research. One of the primary goals of this research is to improve antenna performance and therefore enhance data reception time throughout the day while applying a highly efficient energy system. In order to achieve all of this, a new patch antenna shape was chosen, and it was made as small as possible while still maintaining good operating characteristics in line with all of the earlier goals. This eliminated the need for an antenna deployment procedure once the satellite was in orbit. To further improve the final X-band antenna characteristics and, consequently, the overall efficiency of the accomplished cube satellite, a completely new unit cell shape was chosen and optimized to create the metasurface, which is integrated in the same layer as the developed patch antenna. The created metasurface-integrated patch antenna yielded good measured results in X-band for CubeSat communication after being manufactured and validated in an anechoic chamber and with a vector network analyzer. It has an ultra-wide bandwidth of 7.55 to 9.93 GHz (– 10 dB BW of 2.38 GHz), a unidirectional radiation pattern, is lightweight, and has an adequate realized gain of around 7.0 dBi at 8.4 GHz. The total computed and measured findings, and the reduced dimensions and volume demonstrate that the geometrical, mechanical, and electrical criteria of the 0.5U and 1U CubeSat missions at X-band are satisfied by this new single-layer wide-band metasurface antenna.

In this research, we build, miniaturize, and optimize a smart metasurface antenna to meet the requirements of the smallest cube satellite unit with almost negligible air drag altitude. One of the main objectives of this study is to extend the AeroCube lifetime by adopting far orbits and obtaining significant HPBW angles in order to increase the data reception period throughout the day while using a very efficient energy system. To accomplish all of this, a new antenna shape was adopted, consisting of planar dipole antennas perpendicular to each other, to minimize size to the greatest extent possible while maintaining good operating characteristics in accordance with all previous objectives, without the need for any antenna deployment process after the satellite reaches orbit. Furthermore, a completely new unit cell shape was adopted and optimized to create the metasurface layer, allowing for further enhancement of the final X-band antenna characteristics and, as a result, the overall efficiency of the completed cube satellite. The designed metasurfaced antenna was well manufactured and validated in the anechoic chamber and using vector network analyzer, yielding satisfactory measured results in X-band for CubeSat communication. It is lightweight and exhibit unidirectional radiation pattern with wide 3 dBi gain bandwidth (3 dBi GBW of about 1.0 GHz) and high gain of about 10.0 dBi at 8.4 GHz. The overall results with occupied size and volume are satisfactory for unlimited lifetime CubeSat missions at X-band using all CubeSat structures.

In this paper, the composition of the drag-free CubeSat platform was introduced first. Then the control strategy of drag-free CubeSat orbit keeping was proposed. Finally, the simulation with the control scheme of the Homan transfer orbit was compared. By comparing and analyzing the fuel consumption of the drag-free track and Homan transfer track, it is demonstrated that the continuous drag compensation of the drag-free control scheme can significantly reduce the consumption of thruster mass, and the drag-free technology has good advantages in track stability.

Nanosatellites and CubeSats were first developed for educational purposes. However, their low cost and short development cycle made nanosatellite constellations an affordable option for observing the Earth by remote sensing, increasing the frequency of high-resolution imagery, which is fundamental for studying and monitoring dynamic processes. In this sense, although still incipient, nanosatellite applications and proposed Earth observation missions are steadily growing in number and scientific fields. There are several initiatives from universities, space agencies and private companies to launch new nanosatellite missions. These initiatives are actively investigating new technologies to improve image quality and studying ways to increase acquisition frequency through the launch of larger constellations. So far, the private sector is leading the development of new missions, with proposals ranging from 12 to more than one thousand nanosatellite constellations. Furthermore, new nanosatellite missions have been proposed to tackle specific applications, such as natural disasters, or to test improvements on nanosatellite spatial, temporal and radiometric resolution. The unprecedented combination of high spatial and temporal resolution from nanosatellite constellations associated with improvement efforts in sensor quality is promising and may represent a trend to replace the era of large satellites for smaller and cheaper nanosatellites. This article first reports on the development and new nanosatellite missions of space agencies, universities and private companies. Then a systematic review of published articles using the most successful private constellation (PlanetScope and Doves) is presented and the principal papers are discussed.

Sentinel-2 (S2) imagery is used in many research areas and for diverse applications. Its spectral resolution and quality are high but its spatial resolutions, of at most 10 m, is not sufficient for fine scale analysis. A novel method was thus proposed to super-resolve S2 imagery to 2.5 m. For a given S2 tile, the 10 S2 bands (four at 10 m and six at 20 m) were fused with additional images acquired at higher spatial resolution by the PlanetScope (PS) constellation. The radiometric inconsistencies between PS microsatellites were normalized. Radiometric normalization and super-resolution were achieved simultaneously using state-of–the-art super-resolution residual convolutional neural networks adapted to the particularities of S2 and PS imageries (including masks of clouds and shadows). The method is described in detail, from image selection and downloading to neural network architecture, training, and prediction. The quality was thoroughly assessed visually (photointerpretation) and quantitatively, confirming that the proposed method is highly spatially and spectrally accurate. The method is also robust and can be applied to S2 images acquired worldwide at any date.

CubeSats provide a cost effective means to perform scientific and technological studies in space. Due to their affordability, CubeSat technologies have been diversely studied and developed by educational institutions, companies and space organizations all over the world. The CubeSat technology that is surveyed in this paper is the propulsion system. A propulsion system is the primary mobility device of a spacecraft and helps with orbit modifications and attitude control. This paper provides an overview of micro-propulsion technologies that have been developed or are currently being developed for CubeSats. Some of the micro-propulsion technologies listed have also flown as secondary propulsion systems on larger spacecraft. Operating principles and key design considerations for each class of propulsion system are outlined. Finally, the performance factors of micro-propulsion systems have been summarized in terms of: first, a comparison of thrust and specific impulse for all propulsion systems; second, a comparison of power and specific impulse, as also thrust-to-power ratio and specific impulse for electric propulsion systems.