LAPAN-A3 / IPB microsatellite / LISat of Indonesia
LAPAN-A3/IPB, also referred to as LISat, is a cooperative remote sensing microsatellite project between LAPAN (National Institute of Aeronautics and Space of Indonesia) Jakarta and IPB (Bogor Agricultural University or Institute Pertanian Bogor) located in Bogar, Indonesia. The objective of the demonstration mission is to monitor food resources in Indonesia and to provide environmental monitoring. The real goal of LAPAN-A3/IPB is to provide actual, frequent and accurate data for observing and predicting the condition of the Indonesian archipelago. The Republic of Indonesia with an estimated population of 258 million is the largest archipelago (island country) in the world with more than 17,500 islands, 2/3 of the country's terretory is covered by the sea and 1/3 of the country is land mostly covered by forest and agriculture. — In this cooperative project, LAPAN is responsible for the design and development of the microsatellite, while IPB is in charge for algorithm and dataset application development. 1) 2)
Figure 1: Overview of LAPAN's satellite development program (image credit: LAPAN)
1) LAPAN-A3/IPB was developed based on the LAPAN-A2/ORARI satellite bus with several enhancements to accommodate the linear imager payload.
2) The satellite mission is to identify land cover and land use and to monitor environmental degradation.
3) To perform such a mission, LAPAN-A3/IPB carries a medium resolution multispectral (4-band) imager and a digital camera
4) As the satellite of a maritime country, LAPAN-A3/IPB also supports global maritime traffic monitoring by receiving the AIS signals of ships in the ground segment.
Table 1: Technical specifications of the LAPAN-A3/IPB microsatellite
Figure 2: Two views of the LAPAN-A3/IPB microsatellite (image credit: LAPAN)
Figure 3: Illustration of the data handling concept (image credit: LAPAN)
Launch: LAPAN-A3/IPB was launched on June 22, 2016 (03:56 UTC) as a secondary payload to ISRO's CartoSat-2C spacecraft. The launch site was SDSC (Satish Dhawan Space Center) in India and the launch vehicle is PSLV-C34. 5)
The secondary payloads (19) on this flight were:
• SkySat-3, the first operational satellite (120 kg) in Terra Bella’s constellation of 21 Earth observation satellites.
• BIROS (Bi-spectral InfraRed Optical System), a 130 kg minisatellite of DLR. The BIROS satellite is part of DLR's FireBird constellation, which consists of two spacecraft, TET-1 and BIROS.
- BIROS carries onboard the picosatellite BEESAT-4 (Berlin Experimental and Educational Satellite-4) of TU Berlin(1U CubeSat, 1 kg) and release it through a spring mechanism [ejection by SPL (Single Picosatellite Launcher ) after the successful check-out and commissioning of all relevant BIROS subsystems]. After separation, it will perform experimental proximity maneuvers in formation with the picosatellite solely based on optical navigation.
• M3MSat (Maritime Monitoring and Messaging Microsatellite), a Canadian technology demonstration microsatellite (85 kg) joint mission funded by DND (Department of National Defence) and CSA (Canadian Space Agency), exactEarth and COM DEV Ltd. M3MSat carries two advanced AIS (Automatic Identification System) payloads to monitor maritime shipping.
• LAPAN-A3 (Lembaga Penerbangan dan Antariksa Nasional-A3), an Earth observation microsatellite (115 kg) developed in Indonesia.
• GHGSat-D (Greenhouse Gas Satellite – Demonstrator), a 15 kg commercial venture of GHGSat Inc. of Montreal, Canada, a subsidiary of Xiphos Systems Corporation. GHGSat-D was built at UTIAS/SFL. GHGSat’s mission is to become the global reference for remote sensing of greenhouse gas (GHG) and air quality gas (AQG) emissions from industrial sites, using satellite technology.
• SathyabamaSat, a 2U CubeSat of Sathyabama University (1.5 kg), India. The satellite will measure the densities of the greenhouse gases over the region over which it moves, using an ARGUS 1000 IR Spectrometer.
• Swayam, a 1U CubeSat of the College of Engineering (1 kg), Pune, India.
• 12 Flock-2p Earth observation satellites (3U CubeSats) of Planet Labs (each with a mass of 4.7 kg), San Francisco, CA.
Orbit: Sun-synchronous circular orbit, altitude = 515 km, inclination = 97.5º, local time on descending node (LTDN) = 9:30 hours.
The the LAPAN-A3/IPB mission, this polar sun-synchronous orbit will make about two times contact per day (day and night) of about 11 minutes average. In this limited contact scenario, much of data will be downlinked in near real time to the ground station through - band communication link that contain the information of data imagery and shipping monitoring data as well.
Indonesia is located approximately between 94º45' E and 141º 65' E, equivalent to ~ 5,150 km along the length of the equator (1/8 of the Earth circumference), with the widest breadth between 6º 8' N and 11º 15' S (~ 2000 km). It is an archipelago positioned between the Indian and Pacific Oceans, and between the Asian and Australian continents. However, the need for space utilization in Indonesia is significant to be able to address solutions to the Indonesian people. The remote sensing data are needed for such applications as agriculture, forestry, fishing, etc.
Figure 4: Presentation of LAPAN-A2/ORARI (blue, near equatorial) and LAPAN-A3/IPB satellites (sun-synchronous) orbital coverage for countries like Indonesia (image credit: LAPAN)
• August 5, 2020: LAPAN-A3/LAPAN-IPB was launched in October 2016. This experimental microsatellite carries a multispectral sensor called the Line Imager Space Application (LISA) among several other sensors. The LISA sensor is a pushbroom scanner with 15 meter spatial resolution and four bands, ranging from blue visible to near infrared. One objective of the satellite mission is to monitor forests and agricultural land. Consistent reflectance values of the Earth's surface are important in order to perform forest monitoring using Earth Observation (EO) satellite data. 6)
- However, in mountainous regions, it can be difficult to obtain such consistent values, especially where there are different facing slopes. Slopes that are directly oriented towards the sun receive more light than those facing away from it, thus making them appear brighter in images.
- Although many studies have been conducted on LAPAN-A3 data processing and data applications, only one focuses on topographic correction. The initial assessment by Zylshal (2019) focused on the DEM source for one topographic correction algorithm (Minnaert correction) rather than the algorithm itself. The initial results showed that ALOS World 3D 30 m performed the best on LAPAN-A3.
- The study was conducted in South Sulawesi Province, Indonesia, which is located in the middle of Indonesian archipelago in an ancient and currently inactive volcanic region. The volcanic rock formation is geologically known as Baturappe-Cindakko (Tpbv), as shown in Figure 5.
The slope area comprised mostly of agricultural land (53%) and forest (41%). Small portions of the study area are also covered with bushes and shrubs (4%), settlements (1.5%), as well as water-body (0.5%) as shown in Figure 5C.
Figure 5: Study area: A – Overview of study area on South Sulawesi, Indonesia. B – LAPAN-A3 RGB composite of NIR-R-G, C – Landuse/landcover of the study area taken from visually interpreted SPOT-6 pansharpened image (1.5 meter) acquired on September 14th 2019. Red rectangle in left image indicates the area of interest. The right image is the LAPAN-A3 RGB composite of NIR-R-G (image credit: LAPAN)
- The relief is undulating, with slopes varying from 0 to more than 60 degrees. (Figure 6A, 6B, 6D, 6E). A 23 x 23 km rectangular subset was chosen as the area of interest (AOI). The AOI was specifically selected at mountainous region with different facing slopes to better understand the effect of topographic correction.
Figure 6: The terrain elevation and its derivatives used in this study. A – ALOS World 3D 30 meter, B – Slope map, C – Aspect map, D – Histogram distribution of terrain elevation based on AW3D30, E – Histogram distribution of slopes, F – Histogram distribution of aspects (image credit: LAPAN)
- The LAPAN-A3/LAPAN-IPB (LA3) used in this study were acquired on 28 August 2019 at 09.34 AM local time. The solar azimuth was at 69.4437°, with an elevation of 50.75°. LA3 has four spectral bands, ranging from blue to near infrared. The spatial resolution is 15 meters (Zylshal et al. 2018), and the LA3 imagery came with WGS84 projection. After geometric correction, the LA3 data was then transformed into UTM projection (Zone 50 South).
- For the chosen correction methods, terrain elevation information is needed in order to simulate the acquisition lighting conditions. Various digital elevation models (DEMs) are available free of charge and cover almost the entire globe; namely, the Shuttle Radar Topographic Mission (SRTM); the ASTER Global Digital Elevation Map (GDEM); and the ALOS Global Digital Surface Model (AW3D30). The latter is currently the newest freely available dataset, being released in March 2017. It utilizes the Advanced Land Observing Satellite (ALOS), specifically the PRISM (Panchromatic Remote-sensing Instrument for Stereo Mapping), to compute the elevation, which delivers with approximately 30 meters of spatial resolution.
• March 5, 2018: According to information provided by Robertus Heru Triharjanto of LAPAN, the two satellites, LAPAN-A2 and LAPAN-A3 are operating nominally in 2018 (Ref. 8).
1) LAPAN-A2 has served the amateur radio community in South East-Asia and South America.
2) The AIS (Automatic Identification System) receiver on LAPAN-A2 and on LAPAN-A3 has contributed to maritime surveillance in Indonesian waters.
3) The LAPAN-A3 multispectral imager data has been used by the remote sensing communities in Indonesia.
Figure 7: LAPAN-A2 & LAPAN-A3 data tracking of the Equanimity ship in February 2018. The ship was hiding in Indonesian waters trying to escape from FBI surveillance (image credit: LAPAN)
Figure 8: LAPAN-A2 & LAPAN-A3 data tracking of the Cledonia Sky ship that sailed into a prohibited area and damaged the coral reef at Raja Ampat, Papua in March 2017 (image credit: LAPAN)
• September 2017: As the LAPAN-A3 satellite itself is still an experimental satellite and yet reached its full operational capacity, the project was not yet able to exploit the necessary information to perform the necessary radiometric and atmospheric correction. Therefore, the spectral comparison performed in this study was meant to be a first step towards a more comprehensive radiometric correction of LAPAN-A3 using relative radiometric normalization technique. 7)
- LAPAN-A3/LAPAN-IPB was launched on October 2016 as part of the Indonesian National Institute of Aeronautics and Space program on Space Technology. LAPAN-A3 is carrying multiple payloads including multispectral push-broom imager, digital matrix camera, as well as video camera. The multispectral payload, dubbed as Line Imager Space Application (LISA), has four multispectral bands ranging from visible to near infrared spectrum. With 123 km swath width, it falls between the 185 km of Landsat-8 OLI and the 100 km tiled Sentinel-2A/2B MSI data. With this successful launch, there have not been many comparative analyses between these platform in terms of image quality, classification, and accuracy assessment. Tabel 2 shows the multispectral characteristics of LAPAN-A3 compared to two Sentinel-2 medium resolution EO satellites.
Figure 9: Uneven illumination across-track of LAPAN-A3 LISA Scene. (A) Visual evaluation for uneven illumination over LAPAN-A3 LISA’s whole scene. Red line indicates the transect line for spectral profile drawn from west to east. (B) Spectral profile over the transect line (image credit: LAPAN)
• The LAPAN-A2 spacecraft and its payload are fully operational in February 2016. 8)
Figure 10: LAPAN-A3 image of the Jember regency of the East Java province, acquired with MSI on 19 October 2016 (image credit: LAPAN)
• In October 2016, the LAPAN-A3 mission became operational after completing all in-orbit tests.
Sensor complement: (MSI, DSC, AIS)
Payload data handling: Source data up to 200 Mbit/s; 16 Gbit storage capacity; image frame's attitude and time tagging; CCSDS data packets.
MSI (Multispectral Imager)
MSI, also known as LISA (Line Imager Space Application), is a pushbroom 4-band imager for land use classification and environmental observations with the following features and capabilities:
- 300 mm lens
- 8002 x 4 pixel array
- 12 bit digitization
- Landsat filter for the bands: 0.45-0.52 µm (blue); 0.52-0.60 µm (green): 0.63-0.69 µm (red); 0.76-0.90 µm (NIR)
- Ground resolution = 18 m
- Swath width = 123 km
DSC (Digital Space Camera)
- A CCD imager with a 1000 mm lens
- 2000 x 2000 pixel array
- Ground resolution of 5 m
- Swath width = 10 km
AIS (Automatic Identification System) Receiver
The AIS instrument assembly is designed and developed at KSX (Kongsberg Seatex AS, Trondheim, Norway) supporting global maritime awareness by the reception of AIS signals from ships. The instrumentation is similar to the one flown on AISSAT-1 (launch on July 12, 2010). The AIS instrument features are:
• Simultaneous reception and decoding of any two channels in the maritime VHF band
• SDR‐based radio architecture – upgradeable after launch
• High sensitivity
• Low power consumption
• Industrial grade components used giving a cost‐efficient AIS payload
• RS422 interface.
- Sensitivity of 117 dBm
- Estimated footprint radius of 2800 km
- Max number of ships to be tracked: 104/min.
LAPAN operates a network of ground stations to operate microsatellites (LAPAN-TUBSAT, LAPAN-A2 and LAPAN-A3/IPB). The network consists of ground station in Rumpin and Rancabungur (Bogor), Bukittinggi (West Sumatra), Pontianak (West Borneo)and Biak (Papua). Within the network, Rumpin is the main control station. In addition, as a research ground station, Rancabungur functions as backup for Rumpin, to ensure the reliability of Western Indonesia coverage. A LAPAN-built receiving antenna is installed in Bukittinggi, to cover the far Northwest of Indonesia such as the Aceh province. Another LAPAN-built receiving antenna is installed in Pontianak and Biak, to cover the satellite operation in the Central and Eastern part of Indonesia. In the future, another station will be established in Pare-pare, Celebes, to provide a better coverage of the central part of Indonesia.
Figure 11: Ground station network of LAPAN-TUBSAT, LAPAN-A2 and LAPAN-A3 (image credit: LAPAN)
1) ”LAPAN-IPB LISat satellite will be launched in the mid of 2016,” April 2016, URL:
Chusnul Tri Judianto, Eriko Nasemudin Nasser, ”The analysis of
LAPAN-A3/IPB satellite image data simulation using High Data Rate
Modem,” Elsevier, Procedia Environmental Sciences, Vol. 24, April
3, 2015, , pp: 285 – 296, URL: http://ac.els-cdn.com/S187802961500105X/
3) Information provided by Robertus Heru Triharjanto of LAPAN.
4) HasbiWahyudi, Suhermanto, ”Development of LAPAN-A3/IPB satellite - an experimental remote sensing microsatellite,” Proceedings of 34th ACRS (Asian Conference on Remote Sensing), Bali, Indonesia,October 20-24, 2013
5) ”PSLV-C34 Successfully Launches 20 Satellites in a Single Flight,” ISRO, June 22, 2016, URL: http://www.isro.gov.in/update/22-jun-2016/
6) Zylshal Zylshal”Topographic Correction of LAPAN-A3/LAPAN-IPB Multispectral Image: A Comparison of Five Different Algorithms,” sciendo, published online 5 August 2020, URL: https://content.sciendo.com/view/journals/quageo/39/3/article-p33.xml, Quaestiones Geographicae , Volume 39: Issue 3, https://doi.org/10.2478/quageo-2020-0021
Z. Zylshal, N. M. Sari, J. T. Nugroho, D. Kushardono, ”Comparison
of Spectral Characteristic between LAPAN-A3 and Sentinel-2A,” GSS
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Indonesia, 27 – 28 September 2017, IOP Conference Series: Earth
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:10.1088/1755-1315/98/1/012051, URL: http://iopscience.iop.org
8) Information provided by Robertus Heru Triharjanto of LAPAN.
The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: ”Observation of the Earth and Its Environment: Survey of Missions and Sensors” (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (firstname.lastname@example.org).