A new altimeter for Mars land shape observations utilizing the ionospheric sounder system onboard the Planet-B spacecraft

概要

論文の詳細を見る
A new altimeter has been developed for the observation of the land shape of a planet from an orbiting spacecraft by transmitting RF pulses. The present system utilizes an RF sounder for observing the electron density profile of the topside ionosphere by selecting a transmission frequency f higher than the local cutoff frequency of the ionosphere by adding upper and lower side band modulations with a frequency p; i.e. at frequencies f + p and f-p. The phase difference of the propagating signals at the upper and lower side band frequencies gives a fine delay time with a range resolution of 100 m for p = 50 kHz and 20 m for p = 250 kHz with f = 9 MHz corresponding to a resolution of 6° of the phase detector of the system onboard the spacecraft. Using 600 Watts transmitting power applied to a 52 m tip-to-tip dipole antenna, the altitude of the spacecraft and the land shape can be measured while the spacecraft is in the range below 300 km altitude at the planet.
公益社団法人日本地震学会、地球電磁気・地球惑星圏学会、特定非営利活動法人日本火山学会、日本測地学会、日本惑星科学会の論文