P12 V ORBITING RADAR RESAMPLED ALTIMETER/RADIOMETER V1.0

The measurements were made during each approximately 12-second spacecraft rotation period for a period of 32 minutes on either side of periapsis, when the range to the surface was less than about 4500 kilometers. During those 12 seconds, up to 8 measurements were made: (a) cold-sky received calibration when the antenna pointed to the zenith, (b) 'early' imaging, when the antenna pointer at an angle of between 10 and 40 degrees from nadir, (c) planetary thermal noise temperature when the antenna pointed to the nadir (d) one altimetry measurement, or (d-g) four altimetry measurements, and (h) 'late' imaging, when the antenna again pointed at an angle of between 10 and 40 degrees from nadir, but on the other side from 'early' imaging.