17:15 〜 18:45
[PEM10-P06] Preliminary design of search-coil magnetometer with ASIC devise
キーワード：Magnetomer, Search coil magnetometer, Space exploration, Payload, Miniaturized instruments
Two types of magnetometers generally had been used to understand the space environment in space exploration program since 1950’s. One is the fluxgate and the other is the search coil magnetometer (SCM). The fluxgate magnetometer measures the low-frequency magnetic field from DC to a few Hz and provides high sensitivity. On the other hand, the SCM ranging from mHz to kHz has carried out a high frequency phenomena observation in previous missions like THEMIS, ARASE, and ERG. SCM had been continuously enhanced in various aspects, from sensor to circuit and signal processing, as it is important instrument for space research.
In this study, we introduce the development of lightweight and power reduction the tri-axial Space-SCM(SSCM) for various satellite platforms. The requirement of SSCM is a measurement range from 10 Hz to 20 kHz and a noise equivalent magnetic induction (NEMI) of 10 pT/(Hz)^1/2.
The SSCM consists of induction sensors, AD electronics, and data processors. The induction sensor has several thousand turns of wire wound around a ferromagnetic core as same as general sensors. However, we tested three core types (rod, stacked sheet, rolling sheet) to improve weight efficiency. The Rolling core achieved a mass reduction more than three times with maintaining the performance. The AD electronics include a preamplifier and an ADC. We developed a low power preamplifier with 80 dB gain by application-spec integrated circuit (ASIC) technology. The ADC was selected in the commercial off-the shelf devices. The data processors analyze the signal and produce power spectrograms. For the data processing, we are also manufacturing the ASIC device using verified field programmable gate array (FPGA) logic. In addition, both ASICs are equipped the radiation hardening design for space environment with 65 nm process. And we studied the method using on-board AI device to enhance the data transfer efficiency.
We had conducted a frequency response test and NEMI test with FPGA. The test result of the prototype SSCM is satisfied the requirement specification. The space environmental tests are planned in 2025. We expect that this study provides more lightweight and compact SSCM payload as compared to traditional designs.
In this study, we introduce the development of lightweight and power reduction the tri-axial Space-SCM(SSCM) for various satellite platforms. The requirement of SSCM is a measurement range from 10 Hz to 20 kHz and a noise equivalent magnetic induction (NEMI) of 10 pT/(Hz)^1/2.
The SSCM consists of induction sensors, AD electronics, and data processors. The induction sensor has several thousand turns of wire wound around a ferromagnetic core as same as general sensors. However, we tested three core types (rod, stacked sheet, rolling sheet) to improve weight efficiency. The Rolling core achieved a mass reduction more than three times with maintaining the performance. The AD electronics include a preamplifier and an ADC. We developed a low power preamplifier with 80 dB gain by application-spec integrated circuit (ASIC) technology. The ADC was selected in the commercial off-the shelf devices. The data processors analyze the signal and produce power spectrograms. For the data processing, we are also manufacturing the ASIC device using verified field programmable gate array (FPGA) logic. In addition, both ASICs are equipped the radiation hardening design for space environment with 65 nm process. And we studied the method using on-board AI device to enhance the data transfer efficiency.
We had conducted a frequency response test and NEMI test with FPGA. The test result of the prototype SSCM is satisfied the requirement specification. The space environmental tests are planned in 2025. We expect that this study provides more lightweight and compact SSCM payload as compared to traditional designs.