We report here the in orbit performance of the CCD camera (MAXI/SSC) onboard the International Space Station (ISS). It was commissioned in August, 2009. This is the first all-sky survey mission employing X-ray CCDs. It consists of 32 CCDs each of which is 1 inch square. It is a slit camera with a field of view of 1 • .5×90 • and scans the sky as the rotation of the ISS.The CCD on the SSC is cooled down to the working temperature around −60 • C by the combination of the peltier cooler, a loop heat pipe and a radiator. The standard observation mode of the CCD is in a parallel sum mode (64-binning). The CCD functions properly although it suffers an edge glow when the Sun is near the field of view (FOV) which reduces the observation efficiency of the SSC down to about 30%. The performance of the CCD is continuously monitored both by the Mn-K X-rays and by the Cu-K X-rays.There are many sources detected, not only point sources but extended sources. Due to the lack of the effective observation time, we need more observation time to obtain an extended emission analysis extraction process.
An ultra-broad-band reflection-type phase shifter is proposed. Theoretically, the proposed phase shifter has frequency-independent characteristics in the case of 180 phase shift. The phase shifter is composed of a 3-dB hybrid coupler and a pair of novel reflective terminating circuits. The reflective terminating circuit switches two states of series and parallel LC circuits. Using an ideal circuit model without parasitic circuit elements, we have derived the determining condition of frequency independence of circuit elements. Extending the concept, we can also obtain a broad-band phase shifter for other phase difference as well. In this case, for a given phase difference and an operating frequency, we also derive a condition to obtain minimum variation of phase difference around the operating frequency. This enables the broad-band characteristics for arbitrary phase difference. The fabricated 180 reflective terminating circuit monolithic microwave integrated circuit (MMIC) has achieved a phase difference of 183 3 over 0.5-30 GHz. The 180 phase-shifter MMIC has demonstrated a phase shift of 187 7 over 0.5-20 GHz. The 90 reflective terminating circuit MMIC has performed a phase difference of 93 7 over 4-12 GHz.
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