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This article shows development and performance evaluation of a MicroX-SAR demonstration satellite, scheduled to be launched in 2020 for synthetic aperture radar (SAR) application. This compact SAR system and its instruments are briefly described. The SAR antenna consists of deployable seven panels with a slot array and the antenna size is 4.9 × 0.7 m. This article proposes a simple evaluation method of the SAR antenna. The seven-panel antenna array performance is estimated from isolated single-panel antenna measurement results and synthesized scattering matrix. It is validated by comparing with near-field measurement of a sevenpanel antenna array. The on-board SAR system is combined with a single-point source simulator and the point source SAR image is evaluated. The ambiguity to the signal ratio is computed for the bandwidth-integrated seven-panel antenna radiation patterns, and finally the pulse repetition frequency selection is computed along with noise equivalent sigma zero to estimate the SAR image quality based on various requirements of swath-width and ground-range resolution as per the application of interest. The prototype system is capable of 1-m ground-range resolution SAR image acquisition for 28-km swath-width within acceptable limits of signal-to-noise ratio and ambiguity levels.

This paper presents the proto-flight model results of X band synthetic aperture radar for small satellites including the RF power amplifier, high speed data storage/transmission system, and the ground SAR response test results. The specifications of SAR performance are single polarization SAR with 3m ground resolution for strip map mode. 1 m ground resolution can be achieved with sliding spot light mode under condition of limited value of NESZ at 600km altitude orbit. The data down link is high speed X band down link with 2-3 Gbps. In May, 2019, 2.5Gbps down link with 64APSK modulation in dual polarization channels was demonstrated by RAPIS-1 Satellite. We will launch the first demonstration SAR satellite in 2020 as collaboration with a private company.

This paper presents the engineering model results of this X band synthetic aperture radar for small satellites and its application to constellation missions.The specifications of SAR performance are single polarization SAR with 1m ground resolution at 350 km altitude and with 3m ground resolution at 600km altitude orbit. A satellite is supposed to be 130kg in mass and the size is 0.7m x 0.8m x 0.9m on a rocket. A size of the deployed antenna is 4.9m x 0.7m. A chirped transmitting signal is amplified in a six GaN HEMT 200W amplifier modules to be combined in a waveguide resonator. The type of antenna system is deployable plane antenna due to its compact stow volume. Novel parallel plate slotted array antennas have been developed. We have performed compact range test, near-field measurement of an antenna wing with 2.8m x 0.7m size. The peak aperture efficiency is measured to be higher than 50%. We will launch the first demonstration satellite in late 2019. We finally will build a cons...

In 2018, the Congress of the Philippines is expected to pass the Philippine Space Development Act, leading to the adoption of the first national space policy in the country and the establishment of the Philippine Space Agency (or PhilSA). This historic event is the final outcome of a long process involving various stakeholders in the Philippines from government, academia and industry.

A deployable parallel-plate slot array antenna is being developed for the Synthetic Aperture Radar (SAR) sensor onboard small satellite. This parallel-plate slot array antenna is designed to operate in X-band frequency with vertically polarized radiation. The antenna is designed entirely by using HFSS simulator. From the results of simulation, it is shown that at the center frequency (9.65 GHz), one antenna panel has 35.9 dBi directivity and 65.5% efficiency.

We proposed a new architecture of antenna, transmitter and receiver feeding configuration for small synthetic aperture radar (SAR) that is compatible with 100 kg class satellite. Promising applications are constellations of earth observations together with optical sensors, and responsive, disaster monitoring missions. The SAR antenna is a deployable, passive, honeycomb panel antenna with slot array that can be stowed compactly. RF (radio frequency) instruments are in a satellite body and RF signal is fed to a deployable antenna through non-contacting choke flanges at deployable hinges. This paper describes its development strategy and the present development status of the small spaceborne SAR based on this architecture.

of Antenna Technology for Space-borne SAR Missions 2.2 Challenges for Antenna Design for Small Satellites 2.3 Typical Power and Mass Allocation for different SAR systems 2.4 Strategy for Small SAR Satellites 3.1 MicroX-SAR Mission Parameters with Desired Specifications 3.2 Mass of MicroX-SAR Antenna Components 3.3 MicroX-SAR Antenna Structure Specifications 3.4 Edge-feed Scheme End-feed 'N-1' Slots Design Parameters 3.5 Modified τ-junction Design Parameters 3.6 τ-junction with Slot 'N' Design Parameters 3.7 Designed Parameters of Edge Feeders for Slot 'N' 3.8 Designed Parameters of Slot 'N' with τ-junction of Center-feed Scheme 3.9 Design Parameters of Slot 'N' and Slot 'N-1' with τ-junction of Center-feed 3.10 Design Parameters of Slot 'N' with PMC-junction of Center-feed Scheme 3.11 Design Parameters of Slot 'N' and Slot 'N-1' with PMC-junction 3.12