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formed four times. e phase shier integrated in each antenna element is ve bits in dynamic range, so the phase shi for one bit is 11.25°. en, if the phase shier is set 32 times, it changes 360°. During the WIND REV, one phase condition is kept for every 80 ms. Moreover, in order to distinguish the REV starting point, a transient phase of 0°, 112.50° and 236.25° is added at the beginning of phase rotation. For the WINDS REV, the phase shier is set 35 times including phase setting of 32 points from 0° to +348.75° (phase propagation direction) by steps of 11.25° and a transient phase setting of 3 points.e measurement time of the REV is about 6 minutes for 128 elements. In addition, as the starting time of mea-surement of the satellite and that of the earth were not synchronized, the measurement was started one minute before the starting time of REV and the termination of REV was extended one minute. en, the measurement duration was 8 minutes. Moreover, as the timing of the phase setting of the satellite and the measurement timing at the receiver did not coincide precisely, the measurement duration was 40 ms which was half of the period. erefore, the duration time of 40 ms may fall in the period of 80 ms. Although the real data that falls in the period of 80 ms and false data that crosses the boundary of the 80 ms period as well appear one by one, they can be distinguished in the data post-processing. Figure 4 shows the measure-ment timing of the REV data.Here, there is no time dierence of measurement be-cause the phase setting timing of the APAA and measure-ment timing of the REV data are synchronized with a GPS clock.4.2REV data processing methode REV data for receiving power for phase shi of the antenna element derive 1,024 points of data in a 40 ms interval in the setting of a real-time spectrum analyzer. As this data contains signal and noise including atmospheric uctuation, the eect by atmospheric uctuation is reduced by averaging these 1,024 data points.ere are two REV data sets of real data and false data aer the averaging process. e false data of the two should be discarded as the data contains the boundary of the 80 ms interval. In order to extract the false data, the ampli-tudes of the waveforms can be compared. e amplitude Real-time・Spectrum・AnalyzerIF：3GHzNICTLarge Earth StationAperture：4.8mφJAXA Reference StationWINDS APAA(Non-regenerativeTransponder Mode)Frequency：28.05GHzContinuous Wave(CW)Frequency：18.25GHzContinuous Wave(CW)GPSReceiverReference Signal：10MHzFiF3　REV signal measurements80ms80ms80msAPAA Phase Establish Timing40ms40ms40ms40ms40ms40msSatellite Clock is synchronized to GPS ClockMeasured data in those interval are not correct due to cross the phase establish interval of 80ms.REV Data Measurement TimingMeasured data in those interval are correct due to non-cross the phase establish interval of 80ms.FiF4　REV data measurement timing1293-7 Experimental Reports of APAA Health Test