From 1945, when World War II ended, the Cold War began, marked by endless conflict, confrontation, and competition between the capitalist bloc, led by the United States, and the communist bloc, led by the Soviet Union. The Cold War lasted until 1991, when the Soviet Union collapsed. During the Cold War, the United States and the Soviet Union competed in numerous areas to demonstrate the superiority of their respective systems. Space development is used as a promotional tool to demonstrate scientific and technological capabilities. After World War II, the Soviet Union used thousands of German engineers to accelerate its space program, beginning in the 1950s, and successfully launched the first artificial satellite, Sputnik 1, in October 1957. Following the launch of Sputnik 1, competition between the United States and the Soviet Union in satellite development intensified, with both nations launching various reconnaissance satellites through the CORONA and KOSMOS programs. In July 1958, the United States established the National Aeronautics and Space Administration (NASA) as the national agency in charge of space development to gain an advantage in the space race with the Soviet Union. In the 1970s, as Cold War tensions eased, financial strain from the space race mounted, and the Soviet Union’s space development diminished from the mid-1970s. By contrast, the United States continued to invest heavily in artificial satellites and spacecraft for earth science and space exploration.

Initially developed for military purposes, space technology was used for satellite development for various purposes, such as earth science, broadcasting, and communication, and many countries have begun to pursue satellite development. As a result, there are numerous Earth Observation (EO) satellites around the world, and these satellites are used for various purposes such as surveillance and reconnaissance, climate change, disaster, and crop monitoring.

Although Korea’s history of space development is shorter than that of other advanced countries overseas, it has invested heavily in research and development through a comprehensive space development plan. As a result, Korea now can independently develop world-class low-orbit and geostationary satellites to meet the needs for satellite imagery in fields such as meteorology, ocean, environment, land, and disasters. Additionally, high-resolution multi-sensor images from the Korea Multi-Purpose Satellite (KOMPSAT) series have been instrumental in advancing various image processing technologies (Jang et al., 2019; Choi et al., 2020; Oh et al., 2020; Lee and Yang, 2021; Jung et al., 2022; Jin and Park, 2023, Yu et al., 2023; Hur et al., 2024), with these technologies applied across multiple fields (Sunwoo et al., 2016; Chae et al., 2021; Lee et al., 2023b; Gong et al., 2023; Yang and Kim, 2023). In this study, we introduce the current status of major EO satellites overseas and detail satellite development and utilization in Korea.

2.1. Geoscience Satellite Program

In the early days of space development, many countries focused on developing reconnaissance satellites for military purposes. However, as space technology advanced and the need for satellites to monitor weather and climate changes in the Earth science field, various types of EO satellites were developed. Notable examples include the United States and European Space Agency (ESA)’s Sentinel satellite series.

The United States has operated a variety of satellite programs for Earth science research, beginning with the launch of Landsat-1. The Landsat series is one of the most widely used satellite programs globally, with NASA’s Goddard Space Flight Center (GSFC) in charge of satellite control and the United States Geological Survey (USGS) in charge of image reception, processing, and distribution. Landsat-9, launched in September 2021, provides panchromatic images (15 m), multispectral images (30 m), and Long-Wavelength Infrared (LWIR) images (100 m). It is used for global vegetation and forest monitoring, environmental change tracking, and surface temperature analysis. Fig. 1 shows the status of the various EO satellites used for NASA Earth science missions.

Figure 1. NASA’s Earth science missions (NASA’s Earth Observing System, 2024).

The ESA launched various EO satellites (ERS-1/2: 1991/1995, ENVISAT: 2012), starting with the launch of Meteosat-1 in 1977 for meteorological and climate monitoring. Since 2014, it has also operated several Sentinel satellites since 2014 under the Copernicus program. Most Earth science satellites, such as the Landsat and Sentinel series, offer medium and low spatial resolutions; however, they have a wide imaging width and multiple multispectral bands, allowing for linked use in many fields, such as vegetation, atmosphere, oceans, and disasters. NASA and ESA initiated the Harmonized Landsat and Sentinel-2 (HLS) project to facilitate the joint use of the Landsat and Sentinel-2 data (Fig. 2). This collaboration improved the revisit cycle and data standardization, leading to highly efficient performance in various monitoring studies.

Figure 2. HLS program operation concept: (a) HLS revisited times and scheduled Landsat and Sentinel-2 launch dates and (b) HLS processing workflow. (NASA Earthdata, 2024).

In addition, various science satellites have been launched and utilized, including the National Oceanic and Atmospheric Administration (NOAA) Suomi National Polar-orbiting Partnership (NPP), NASA Moderate Resolution Imaging Spectroradiometer (MODIS), and JAXA Advanced Land Observing Satellite (ALOS).

2.2. Current Status of Commercial Satellites

Space technology is a prime example of a dual-use civilian and military technology, with significant technological spillover effects. The space industry, based on various space technologies, has the potential to stimulate related industries and create new markets, contributing to what is often referred to as a space economy. In the past, many satellites were available for military purposes, but civilian commercial satellites now dominate the market. Many private companies in the United States, Europe, Japan, and Canada are developing new satellites and creating service markets through technological innovations based on various business models. In today’s New Space era, private companies are emerging as the key drivers of space technology innovation, backed by substantial capital.

In 2013, the U.S. government established the “National Strategy for Civil Earth Observation” to promote data integration, accessibility, and openness, aiming to increase the use of satellite imagery in various sectors. In 2014, the U.S. government revised the law to relax the existing resolution standards for satellite imagery sales, reducing the limit from 50 cm to 25 cm, which enabled the private commercial use of ultra-high-resolution satellite imagery. The first submeter (82 cm) high-resolution commercial satellite, IKONOS of Space Imaging (now Maxar Technologies), was granted a license by the U.S. Department of Commerce in 1994 to sell high-resolution satellite images commercially. IKONOS was initially designed as twin optical satellites; however, after the failure of the first launch in April 1999, the second satellite was successfully launched in September 1999, and commercial sales of the satellite images began in January of the following year. Since then, QuickBird-2 (2001, 65 cm), GeoEye-1 (2008, 41 cm), and WorldView-1–4 (2007–2016, 50–31 cm) were launched. Maxar Technologies is now operating satellites as a constellation system, including the WorldView Legion series (1–4, 30 cm-class) from 2024. Fig. 3 shows an image with 15 cm spatial resolution using High-Definition (HD) processing.

Figure 3. WorldView-3 image with HD processing: (a) native resolution image and (b) HD processing image (Maxar Technologies, 2022).

The French Airbus Defense & Space (D&S) entered the commercial imagery market in the 1980s with the SPOT (10 m) satellite and has since launched and operated Pleiades-1A (2011)/1 B (2012) with a spatial resolution of 50 cm. It currently sells 30 cm images through Pleiades Neo-3/4, launched in 2021, and, similar to the WorldView series, provides 15 cm spatial resolution images by post-processing. In Fig. 4, Airbus D&S creates 3D texture models using ultra-high-resolution images and various high-value-added products such as Digital Elevation Model (DEM) using TerraSAR-X and TanDEM-X, which operate jointly with the German Aerospace Center (DLR).

Figure 4. AirBus D&S value-added products: (a) 3D texture model using an ultra-high-resolution image and (b) DEM generation using TerraSAR-X image (source: https://intelligence.airbus.com).

Various Synthetic Aperture Radar (SAR) satellites have been launched, including Radarsat-1 (1995, 10 m)/2 (2007, 1 m) from Canada’s MacDonald, Dettwiler, and Associates (now MDA Space), and COSMO-SkyMed-1/4 (2007–2010, 1 m) from Italy’s Agenzia Spaziable Italiana (ASI).

The Earth science and private commercial satellites are typically large and heavy (>2,000 kg) due to their various high-performance functions. While large satellites have the advantage of high spatial resolution and many multispectral bands due to the high performance of their payloads, but they also have the disadvantage of requiring a huge budget and a long development period in terms of satellite development. Additionally, the small number of satellites limits continuous image acquisition through rapid revisiting is limited. In the New Space era, advancements in satellite manufacturing, driven by private capital and innovative technology, are leading to increased efficiency through miniaturization and weight reduction of satellite components. This has lowered manufacturing and launch costs, reducing entry barriers to the satellite industry. As a result, many small- and medium-sized companies are now developing and launching various satellites, such as micro constellation satellites. Satellites weighing less than 100 kg are classified as microsatellites; which can be further subdivided into various types based on their weight.

PlanetScope, a nanosatellite developed by Planet Labs (USA), is the most widely used satellite constellation globally, with approximately 130 satellites in operation. PlanetScope, which weighs 5.8 kg, has an imaging width of approximately 32 km and provides images with a spatial resolution of approximately 3 m (3.7 to 4 m). SkySat, which is operated by Planet, is composed of 21 satellites weighing approximately 110 kg and provides images with a spatial resolution of 50 cm and an imaging width of 6 km, and video images with a spatial resolution of 80 cm at 30 frames per second. In addition, various microsatellites have been launched and are in operation (Table 1). They are very useful for ship detection, change detection, crop monitoring, and disaster surveillance (Fig. 5).

Figure 5. A case of micro-satellite applications. (a) Crop monitoring (Planet Labs, 2024). (b) Suez Canal container ship accident (Satellogic, 2024). (c) Ship detection (ICEYE, 2024). (d) Change detection (Capella Space, 2024).

Table 1 . Status of micro-satellites (As of July 2024).

Nationality	Japan	U.S.A.	Argentina	Finland	U.S.A.	U.S.A.
Company	Axelspace	BlackSky	Satellogic	ICEYE	Capella Space	Umbra
Satellite	GRUS	Global	NewSat	ICEYE	Capella	Umbra
Number of satellites	5	16	40	31	18	8
Sensor type	Multispectral	Multispectral	Multispectral	SAR	SAR	SAR
Spatial resolution	2.5 m	1 m–0.8 m	1 m–0.7 m	0.5 m	0.5 m	0.25 m
Swath width	57 km	6 km	6.5 km	5 km	5 km	5 km
Weight	Around 100 kg	> 44 kg	Around 40 kg	Around 100 kg	Around 40 kg	Around 70 kg
Launch	2018 ~	2016 ~	2016 ~	2018 ~	2018 ~	2021 ~

Commercial microsatellites from private companies are being used efficiently for surveillance, reconnaissance, change monitoring, and more due to their high temporal resolution and fast revisit cycles, achieved through constellation operations of multiple satellites. Notably, some companies are developing innovative business models to enhance user convenience, by automatically detecting various objects from microsatellite images and providing services in near real-time using artificial intelligence (AI), big data, and cloud technologies.

While major countries, such as the United States, Russia, the United Kingdom, and Canada began launching satellites in the 1950s and the 1960s, Korea started its space development in the early 1990s. To ensure sustainable and systematic space development, the Korean government formulated the Space Development Mid- and Long-Term Plan (now Master Plan for the Promotion of Space Development) in 1996, and enacted the Space Development Promotion Act (hereinafter referred to as “Act”) in 2005. The purpose of this Act is to facilitate the peaceful use and scientific exploration of outer space and contribute to national security, the sound growth of the national economy, and the improvement of citizens’ lives by systematically promoting the development of outer space and efficiently using and managing space objects (Space Development Promotion Act, 2024).

To support space development and manage space objects such as satellites, the Korean government formulates the Master Plan for the Promotion of Space Development (hereinafter referred to as “Master Plan”) every five years, outlining mid- and long-term policy objectives and the strategic direction-setting for space development. The Master Plan includes the following (Space Development Promotion Act, 2024):

• Matters concerning objectives and strategic direction-setting of space development policies

• Matters concerning systems and strategies to pursue space development

• Matters concerning plans to pursue space development

• Matters concerning research and development for space development, etc.

In line with the Master Plan, the development and implementation of various low-orbit and geostationary satellites, including KOMPSAT, were promoted to meet the needs of the Korean government. The 4th Master Plan (2023–2027) was established in December 2022 to transition toward Space Development 2.0 a Policy, aimed at realizing a space economy. Fig. 6 shows the satellite development roadmap presented in the 4th Master Plan. Although the satellite launch schedule (Fig. 6) was slightly delayed owing to the COVID-19 pandemic, the launches are expected to proceed sequentially without major issues.

Figure 6. Satellite development roadmap (Joint of Relevant Ministries, 2022).

To promote the dissemination and utilization of satellite images, the Korean government formulates a Master Plan for the Utilization of Satellite Information (hereinafter referred to as “Master Plan for the Utilization of Satellite Information”) every five years. This plan includes the following (Space Development Promotion Act, 2024);

• Matters concerning objectives and direction for the dissemination and utilization of satellite information

• Matters concerning the acquisition of satellite information

• Matters concerning a system for the dissemination of satellite information and a plan for its utilization

• Matters concerning the demand, trends, research, and development of technologies utilizing satellite information

The 3rd Basic Plan for Satellite Information Utilization (2024–2028) is expected to be announced soon. Its goal is to foster a private sector-led satellite information industry ecosystem and increase public value through satellite data, thereby accelerating the realization of a space economy.

The Korea Aerospace Research Institute (KARI), established in 1989 with funding from the Korean government, under the Aerospace Industry Development Promotion Act (Act No. 3991, Enforcement date December 5, 1988), plays a pivotal role in the nation’s aerospace-related technologies but also in supporting national development policies. Currently, KARI has secured the world’s most advanced satellite design, analysis, manufacturing, assembly, and testing technologies to meet various domestic satellite demands (Korea Aerospace Research Institute, 2024). Until now, KARI has been in charge of developing KOMPSAT as a specialized space development organization, and has developed the world-class KOMPSAT series through continuous research and development.

The research and development of satellites in Korea began in 1994, when the General Science and Technology Council approved the KOMPSAT Development Project (Korea Aerospace Research Institute, 2024). The development of KOMPSAT has pushed ahead to secure independent satellite development technology and obtain satellite images for public demand. The KOMPSAT is a low-orbit EO satellite that acquires various satellite images with payloads such as an electro-optical sensor, SAR, and Middle-Wave Infrared (MWIR, 3.3–5.2 µm) sensor. It is used in agricultural and forestry management, land and ocean monitoring, environmental monitoring, and disaster response. Table 2 presents the major specifications of each KOMPSAT series.

Table 2 . Major specifications of the KOMPSAT series.

Satellite	KOMPSAT-1	KOMPSAT-2	KOMPSAT-3	KOMPSAT-3A	KOMPSAT-5
Satellite shape
Sensor type	Optical	Optical	Optical	Optical+IR	SAR (X-band)
Altitude	685 km	685 km	685 km	528 km	550 km
Local time	10:50	10:50	13:30	13:30	06:00/18:00
Spatial resolution	Pan: 6.6 m	Pan: 1 m MS: 4 m	Pan: 0.7 m MS: 2.8 m	Pan: 0.55 m MS: 2.2 m MWIR: 5.5 m	HR: 1 m ST: 3 m WS: 20 m
Swath width	17 km	15 km	16 km	12 km	HR: 5 km ST: 30 km WS: 100 km
Weight	470 kg	800 kg	980 kg	Around 1,100 kg	Around 1,400 kg
Mission lifetime	3 years	3 years	4 years	4 years	5 years
Launch date	1999.12.21	2006.07.28	2012.05.18	2015.03.26	2013.08.22
Operation status	End of Miss. (2007.12)	End of Miss. (2015.10)	In operation	In operation	In operation
Sample image

4.1. KOMPSAT-1

KOMPSAT-1, Korea’s first practical satellite, was jointly developed by KARI and Thompson Ramo Wooldridge Inc. (TRW Inc.) (now Northrop Grumman Corporation) in the United States and launched on December 21, 1999. KOMPSAT-1 was equipped with three cameras: an Electro-Optical Camera (EOC), an Ocean Scanning Multispectral Imager (OSMI), and a Space Physics Sensor (SPS) for mapping, ocean chlorophyll monitoring, and space environment monitoring, respectively. The EOC was primarily used for terrestrial observation and provided only panchromatic images with a spatial resolution of 6.6 m. By contrast, OSMI was used to monitor ocean chlorophyll and typhoons around the Korean Peninsula, offering images with a spatial resolution of 1 km and an observation width of 800 km. It could operate with six selectable spectral bands. Fig. 7 presents the first public image of the Korean Peninsula and examples of major image applications. KOMPSAT-1 performed exceptionally well in a sun-synchronous orbit for eight years, until its mission ended in December 2007. KOMPSAT-1 acquired approximately 470,000 images during its mission, orbiting the Earth more than 43,000 times at an altitude of 685 km (Lee et al., 2021).

Figure 7. Examples of KOMPSAT-1 EOC/OSMI applications. (a) The first public images of the Korean Peninsula taken on January 20, 2000. (b) Chlorophyll-a estimated by OSMI on September 26, 2000. (c) Typhoon SAOMAI observed by OSMI on September 14, 2000.

4.2. KOMPSAT-2

Based on its experience developing KOMPSAT-1, KARI successfully developed KOMPSAT-2 in 2006, which became the world’s seventh satellite with a spatial resolution of 1 m. KOMPSAT-2 is an entirely domestic development initiative aimed at advancing Korea’s satellite manufacturing technology. The multispectral camera (MSC), which is the onboard camera of KOMPSAT-2, was jointly developed by KARI and ELOP Inc., Israel (Lee et al., 2021). The spatial resolution of the KOMPSAT-2 MSC was approximately 40 times higher than that of the KOMPSAT-1 EOC and provided a spatial resolution of 4 m multispectral (RGB+NIR) images. KOMPSAT-2 was launched in 2006, and its official mission ended in 2015 after two mission extensions; however, it has continued to perform imaging missions since then. Until the end of its mission, KOMPSAT-2 was utilized for thematic mapping, disaster monitoring, and forest and agricultural management based on its high spatial resolution. Fig. 8 compares the spatial resolutions of the KOMPSAT-1 EOC and KOMPSAT-2 MSC images.

Figure 8. Comparison of KOMPSAT-1 EOC (6.6 m) image and KOMPSAT-2 MSC image (1 m). (a) KOMPSAT-1 EOC image acquired in March 2006. (b) KOMPSAT-2 MSC image acquired in November 2006.

4.3. KOMPSAT-3

KOMPSAT-3, the successor satellite to KOMPSAT-2, is Korea’s first submeter high-resolution EO satellite developed to meet the country’s growing demand for high-resolution satellite imagery. During the development, KARI established independent domestic processes for satellite development, including bus systems, payload sensors, system assemblies, and tests. KOMPSAT-3 orbits Earth approximately 15 times a day at an altitude of 685 km and collects high-resolution imaging data for land management, water resource management, environmental and ocean surveillance, and disaster monitoring through Earth observations. KOMPSAT-3 can effectively acquire images not only through the traditional strip imaging mode but also through multi-point imaging and single-pass stereo imaging modes (Fig. 9). In particular, single-pass stereo imaging mode can be useful for generating more precise terrain information because it can acquire stereo images without time differences in the same orbit. Additionally, unlike KOMPSAT-2, which obtains images at 10:50 AM (local standard time, LST), KOMPSAT-3 obtains images at 1:30 PM (LST), allowing for more efficient acquisition of images when combined with KOMPSAT-2. KOMPSAT-3 successfully completed its initial four-year mission and is currently operating normally through a mission extension.

Figure 9. KOMPSAT-3 imaging modes. (a) Strip imaging mode. (b) Single-pass stereo imaging mode. (c) Multi-point imaging mode.

4.4. KOMPSAT-3A

The mission objectives of KOMPSAT-3A were to provide continuous EO images after KOMPSAT-2 and KOMPSAT-3 and to meet the nation’s demand for high-resolution images required for Geographical Information Systems (GIS), disaster, land, and ocean monitoring applications. KOMPSAT-3A is the first Korean satellite equipped with high-resolution optical and MWIR sensors. Few advanced countries have developed high-resolution MWIR sensors for low-orbit satellites. KOMPSAT-3A can acquire images even at night using its high-performance MWIR sensor (Fig. 10); therefore, it can be used for day and night change and environmental monitoring. Except for the MWIR sensor, the satellite shape and main components of KOMPSAT-3A are similar to those of KOMPSAT-3. However, to obtain higher-resolution images, the flight altitude was lowered to 528 km, and the performance of major components such as the payload was improved. Meanwhile, satellite weight increased due to the installation of the MWIR sensor, and the imaging width was reduced to 12 km, which is inversely proportional to the spatial resolution. In addition, the operating methods, such as the imaging mode, are similar.

Figure 10. KOMPSAT-3A MWIR pseudo color images. (a) Seoul daytime image (April 1, 2015). (b) Baek-du Mountain night-time image (April 4, 2015).

4.5. KOMPSAT-5

The goal of the KOMPSAT-5 project was to develop Korea’s first SAR satellite for all-weather and day-night monitoring of the Korean Peninsula. It aims to meet the national and commercial demands for SAR images and to establish a technical foundation for entering the global space industry. With the successful launch of KOMPSAT-5, Korea now has high-resolution optical, SAR, and MWIR satellites, enabling the widespread use of multisensory images in various fields, including ocean and land observation, disaster monitoring, and environmental monitoring. The main payload of KOMPSAT-5 is the Corea SAR Instrument (COSI), which is a SAR imaging system. The secondary payload is the Atmosphere Occultation and Precision Orbit Determination (AOPOD) which consists of an L1/L2 dual frequency GPS receiver and laser retro reflector. KOMPSAT-5’s COSI provides X-band SAR images with spatial resolutions of 1 m (high-resolution mode), 3 m (standard mode), and 20 m (wide-swath mode) depending on the imaging mode. After launch, four operational modes—enhanced high-resolution mode with spatial resolution of 1 m (observation width of 3 × 3 km), ultra-high-resolution mode of 0.85 m (2.7 × 2.7 km), enhanced standard mode of 2.5 m (30 km), and enhanced wide swath mode of 5 m (100 km)—through post-launch performance improvement to provide improved high-resolution and high-quality images. Since its launch in 2013, the KOMPSAT-5 has operated stably through an extension of its mission. Fig. 11 shows images of the Colosseum in Rome, Italy, acquired by the KOMPSAT-3 optical and KOMPSAT-5 SAR systems. Because SAR images differ from optical images in terms of imaging methods and characteristics, they can be used independently. However, combining SAR with optical images enhances the synergy effect in data applications.

Figure 11. Images of the Colosseum in Rome, Italy. (a) KOMPSAT-3 image (March, 2013). (b) KOMPSAT-5 image (May, 2015).

4.6. KOMPSAT Follow-up Series

Currently, KARI is focused on developing a follow-up satellite for the existing KOMPSAT. Although the launch schedule for these follow-up satellites has been delayed owing to the COVID-19 pandemic and the Ukraine-Russia war, the launches were expected to proceed sequentially, starting with KOMPSAT-6. KOMPSAT-6 is a successor satellite to KOMPSAT-5 and will feature an upgraded X-band SAR system, with enhanced capabilities, including support for 0.5 m spatial resolution images and multi-polarization functionality. KOMPSAT-7 is currently under development as a follow-up satellite to KOMPSAT-3. KOMPSAT-7 aims to develop core technologies for the 0.3 m-class ultra-high-resolution optical satellite that the world’s major countries are competitively developing and will be equipped with the Advanced Earth Imaging Sensor System-High Resolution (AEISS-HR), a high-resolution electro-optical camera with the world’s highest resolution of 0.3 m-class. KOMPSAT-7A is under development as a follow-up satellite to KOMPSAT-3A, and its main specifications are similar to those of KOMPSAT-7. However, the spatial resolution of the MWIR sensor is expected to be better than that of the KOMPSAT-7, and the MWIR image will consist two bands. The KOMPSAT follow-up series is being developed to achieve world-class performance, thereby satisfying various public and private high-resolution multi-sensor image demands.

Over the past 40 years, the Korean Society of Remote Sensing (KSRS) has published the Korean Journal of Remote Sensing (KJRS), the most authoritative journal in Korea related to remote sensing. This study analyzed the research status of KOMPSAT-related papers among the numerous papers published in the KJRS over the past 40 years. After checking the research topics and content of all papers published in the KJRS since 1985, it was found that there were 223 papers related to KOMPSAT. However, in studies that used multiple satellites, only the most recent satellite was counted. Fig. 12 shows the status of KOMPSAT-related papers published in the KJRS over the past 40 years. The analysis is divided into 11 research fields. Among the satellites, research related to KOMPSAT-3A was the most common, and among the research fields, research related to data processing was the most common.

Figure 12. Status of KOMPSAT-related papers published in the KJRS over the past 40 years.

A survey of research fields using satellite data revealed that KOMPSAT-1 has contributed to numerous system-related research (Fig. 13a), with a significant focus on ocean chlorophyll research using the OSMI (Lim et al., 2000; Sohn et al., 2000; Kim et al., 2002; Suh et al., 2002; Lim et al., 2003). Additionally, KOMPSAT-1 images have been employed in various research and application areas of remote sensing, yielding valuable results (Im et al., 2000; Jeong and Kim, 2000; Ye and Lee, 2000; Ha et al., 2002; Kim and Lee, 2003; Choi et al., 2004). Fig. 13(b) illustrates the results of updating the existing land-use map using the time-series KOMPSAT-1 EOC images.

Figure 13. KOMPSAT-1 image utilization status. (a) Utilization status by research topic. (b) Example of land use update using KOMPSAT-1 EOC images (Kim and Lee, 2003).

Unlike KOMPSAT-1, KOMPSAT-2 provides multispectral bands making it extensively used in image processing fields (Fig. 14a), such as image fusion and image classification (Oh et al., 2012; Kim et al., 2013; Lee et al., 2014; Sunwoo et al., 2016). Additionally, various sensor modeling and DEM creation studies have been conducted based on the high-resolution characteristics of KOMPSAT-2 images (Rhee et al., 2009; Tserennadmid and Kim, 2009; Rhee et al., 2011; Oh et al., 2017). Fig. 14(b) presents examples of various image fusion studies using KOMPSAT-2 images.

Figure 14. KOMPSAT-2 image utilization status. (a) Utilization status by research topic. (b) Example of KOMPSAT-2 image (May 8, 2010) fusion results (Oh et al., 2012).

KOMPSAT-3 was also the most widely used for research related to image processing (Fig. 15a); compared to KOMPSAT-2, KOMPSAT-3 was confirmed to be used evenly across various research fields such as forestry, agriculture, and disasters (Hwang et al., 2014; Choi et al., 2017; Han et al., 2017; Won et al., 2019; Jeong et al., 2020; Jung et al., 2020). Single-pass stereo images of the same orbit have been actively used in data processing research, such as sensor modeling and mapping (Jeong et al., 2014; Oh et al., 2018; Oh et al., 2020). Fig. 15(b) shows an example of the damage analysis from a large-scale forest fire that occurred in Gangneung and Donghae in 2009.

Figure 15. KOMPSAT-3 image utilization status. (a) Utilization status by research topic. (b) Example for analysis of forest fire damage using KOMPSAT-3 image (April 5, 2019) (Won et al., 2019).

Most KOMPSAT-related studies used KOMPSAT-3A images. In particular, they have been used extensively in image processing fields (Fig. 16a), such as object detection, image segmentation, and image registration (Chae et al., 2022a; Kim and Kim, 2023). Furthermore, KOMPSAT-3A, based on high spatial resolution and MWIR images, has been widely used for sensor modeling, surface temperature extraction (Fig. 16b), and disaster analysis (Kim, 2022; Lee et al., 2023a; Hur et al., 2024).

Figure 16. KOMPSAT-3A image utilization status. (a) Utilization status by research topic. (b) Surface temperature extracted using KOMPSAT-3A MWIR image (November 14, 2015) (Kim, 2022).

KOMPSAT-5 had the most ocean-related studies, with nine papers on ship detection, sea surface wind, and sea ice tracking (Fig. 17a). The next most common study focused on data processing related to change detection. Similarly, KOMPSAT-5, which is capable of all-weather and day-night imaging, has been widely used in various research fields such as flood detection like Fig. 17(b) (Ye, 2015; Kim et al., 2019), marine vessel detection (Hwang et al., 2017; Kim et al., 2018; 2020), sea ice research (Chae et al., 2021), change detection (Chae et al., 2022b), and SAR signal processing research (Lee, 2017; Yang and Jeong, 2018; Lee and Yang, 2021).

Figure 17. KOMPSAT-5 image utilization status. (a) Utilization status by research topic. (b) Estimated water areas from KOMPSAT-5 HH image (July 29, 2018) (Kim et al., 2019).

Today, in the New Space era, many countries, including Korea, are investing in space development. EO satellites are continuously being developed to satisfy the increasing demand for satellite images from the public and private sectors. Korea is striving to advance the KOMPSAT series through space development programs while also establishing and implementing a comprehensive plan to maximize their utilization. Moreover, the KJRS, published periodically by the KSRS, has contributed greatly to the development of the field in relation to remote sensing research in Korea. Since the first issue of the first volume was published in 1985, the KJRS has published various research papers in the field of remote sensing for 40 years. This study investigated the KOMPSAT-related papers published in the KJRS over the past 40 years, classified them by research topic, and analyzed their utilization status. KOMPSAT-3A images, which have the highest spatial resolution and were launched recently, were utilized the most, and KOMPSAT images were utilized the most in the fields of data processing and systems (including satellite and ground systems). Furthermore, the KOMPSAT series has been used in various research fields such as disaster, environmental, and ocean research, contributing to the development of remote sensing technology. As more advanced KOMPSAT follow-up satellites are launched, it is expected that the range of applications of satellite images will expand, with related technologies evolving rapidly.

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (Ministry of Science and ICT) (RS-2022-00165154, “Development of Application Support System for Satellite Information Big Data”).

No potential conflict of interest relevant to this article was reported.