RazakSAT™ is Malaysia's second earth observation satellite. The Medium-sized Aperture Camera (MAC) is the instrument payload to be flown on the RazakSAT™. MAC operates on visible and near infrared wavelength (VNIR), including four multispectral bands from 450nm -890nm and one panchromatic band from 510nm to 730nm. Its ground pixel resolution is 5m for multispectral bands and 2.5m for panchromatic band. At 685km nominal altitude, the image swath width for MAC is 20km. RazakSAT™ is scheduled to be launched into 9 o inclination Near-Equatorial Orbit (NEqO) on April 2009. It provides a high number of passes (14 times per day over Malaysia) for communication with ground station, and imaging opportunity increases by 3 times more compared to a sun-synchronous orbit. In order to give user quality assurance of the operational imagery, ground calibration (preflight calibration) has been conducted. This report outlines the techniques adopted during pre-flight calibration of the radiometric response of the MAC system. Results from system level measurement of the instrument response, namely the dark response, signal-to-noise ratio (SNR), saturation radiance, dynamic range, characterization of individual detector, gain and linearity analysis for each spectral band are presented and discussed.

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Sentinel-2A remote sensing satellite system was recently launched, providing free global remote sensing data similar to Landsat systems. Although the mission enables the acquisition of 10 m spatial resolution global data, the assessment of Sentinel-2A data performance for mapping in Malaysia is still limited. This study aimed to investigate and assess the capability of Sentinel-2A imagery in mapping urban areas in Malaysia by comparing its performance against the established Landsat-8 data as well as the fusion datasets from combining Landsat-8 and Sentinel-2A datasets and using Wavelet transform (WT), Brovey transform (BT) and principal component analysis. Pixel-based and object-based image analysis (OBIA) classification approaches combined with support vector machine (SVM) and decision tree (DT) algorithms were utilized in this assessment, and the accuracy generated was analysed. The Sentinel-2A data provided superior urban mapping output over the use of Landsat-8 alone, and the fusion datasets do not yield advantages for single-scene urban mapping. The highest overall accuracy (OA) for pixel-based classification of Sentinel-2A images is 84.77 % by SVM, followed by 65.27 % using DT. BT produced the highest OA for the fusion images of 78.40 % with SVM and 52.21 % with DT. For the object-based classification of Sentinel-2A images, the highest OA is 71.33 % by SVM, followed by 76.38 % using DT. Similarly, the highest OA of fusion images is obtained by BT of 50.35 % with SVM, followed by 65.66 % with DT. From the analysis, the use of SVM pixel-based classification for medium spatial resolution Sentinel-2A data is effective for urban mapping in Malaysia and useful for future long-term mapping applications. HIGHLIGHTS An accurate mapping of urban land is still challenging and requires high image quality of spectral and spatial aspects to identify features Single and fusion image analysis conducted in order to investigate and assess the most performing interpretation result by grouping out the features classes Statistical performance and image classification comparison is relevant to prove the most effective result among the images GRAPHICAL ABSTRACT

Assembly, Integration and Test Centre at National Space Agency (ANGKASA) consist of Reverberation Acoustic Test Facility (RATF). The test facility are used to generate very high sound pressure levels for satellite testing, space vehicle components including flight hardware. This reverberant type of chamber is capable to simulate acoustic field of rocket launch. This paper is discussed on the requisite of high-intensity acoustic testing. The characteristic of chamber and the noise generating capabilities for high-intensity acoustic testing are described. The maximum requirement of chamber at 155dB spectrum profiling result is discussed in this paper.