Všechny publikace

Magnetometry package for LVICE2 mission - Triaxial fluxgate and AMR magnetometer for scientific data production near Moon

  • DOI: 10.1109/SENSORS56945.2023.10325159
  • Odkaz: https://doi.org/10.1109/SENSORS56945.2023.10325159
  • Pracoviště: Katedra měření
  • Anotace:
    LVICE2 is a planned mission to the vicinity of the Moon. It is intended to measure dust particle concentrations in Kordylewski clouds, study turbulences in solar wind, and provide long-term monitoring. The probe will have three magnetometers. A fluxgate magnetometer with a unique inner structure placed on a 2-meter-long boom will provide the main scientific data, while a compact AMR magnetometer located at the edge of the boom will help minimize the residual magnetic signature of the probe itself. The development of both magnetometers is presented as well as the first testing results. The third (search-coil) magnetometer for measurement at higher frequencies is not covered here.

Inkjet-printed Mn-Zn ferrite nanoparticle core for fluxgate

  • DOI: 10.1016/j.jmmm.2022.170003
  • Odkaz: https://doi.org/10.1016/j.jmmm.2022.170003
  • Pracoviště: Katedra mikroelektroniky, Katedra měření
  • Anotace:
    Non-planar fluxgate sensors measuring the magnetic fields in the uT range are required for electric current, position, and torque transducers. We report the first sensor based on an inkjet-printed 17 mm diameter ring core. The sensor wide open-loop linear range of  1.5 mT allows to operate it without feedback. We describe the preparation of the very stable magnetic ink based on citrate-stabilized 13 nm diameter Mn-Zn ferrite nanoparticles that occur in superparamagnetic regime at room temperature. By printing 100 layers the total thickness of the inkjet-printed core was 2.2 µm. The achieved sensitivity was 10 mV/mT for 25 kHz excitation frequency

Characterization of a Digital AMR Magnetometer for Space Applications

  • DOI: 10.1109/TIM.2020.3043867
  • Odkaz: https://doi.org/10.1109/TIM.2020.3043867
  • Pracoviště: Katedra měření
  • Anotace:
    In this paper, we present research, development, calibration and characterization of a novel concept of a digitally compensated, low-noise magnetometer based on anisotropic magnetoresistance sensors that is suitable for space applications. The main idea of the design was to reduce the number of precise analog components while using the digital signal processing power available in a modern microcontroller. Our most recent effort targeted lowering power consumption, enhancement of radiation hardness and overall improvement of the parameters. The principle of operation is presented in detail, along with a detailed description of the instrumentation used to characterize the real instrument, including its noise, linearity, and temperature stability in the range of -20 to +70 °C. The results of total ionizing dose (TID) testing at a gamma-ray irradiation facility are discussed at the complete magnetometer and part levels. This is an extended version of a paper presented at I2MTC 2020 that contains the results of a second radiation test done with a slightly modified design. The instrument worked well throughout the entire irradiation session (TID of 1.05 kGy over 72 hours), and the stability of main parameters was very good (50 pT/Gy offset and 1 ppm/Gy sensitivity stability).

Low frequency noise investigation of pT-level magnetic sensors by cross-spectral method

  • DOI: 10.1109/SENSORS47087.2021.9639875
  • Odkaz: https://doi.org/10.1109/SENSORS47087.2021.9639875
  • Pracoviště: Katedra měření
  • Anotace:
    We present a simple method to estimate the noise of magnetic sensors running in the Earth’s field range by establishing the cross-power spectrum density during ambient field operation and performing spectral subtraction. This method has advantages to the usual subtraction of two sensors outputs, mainly in requirements for synchronization of the sample rate and gain calibration. With this method, verified in simulation and measurements with AMR magnetometers, we could use a fluxgate as a second sensor in order to estimate the low-frequency noise of an HTS SQUID in the ambient field.

1-pT noise fluxgate magnetometer for geomagnetic measurements and unshielded magnetocardiography

  • DOI: 10.1109/TIM.2019.2949205
  • Odkaz: https://doi.org/10.1109/TIM.2019.2949205
  • Pracoviště: Katedra měření
  • Anotace:
    We present the development of a low-noise, fundamental-mode, orthogonal fluxgate magnetometer with four amorphous, annealed ferromagnetic wires. The 1-Hz noise obtained in open-loop and closed-loop is as low as 0.75 and 1.5 pTrms/√Hz, respectively, with white noise level about 0.6 pTrms/√Hz. This is to our knowledge the lowest figure published for a fluxgate magnetometer so far. We compared the instrument performance to a low-noise observatory magnetometer when doing geomagnetic measurements and show that it is fully suitable for measurements at mHz frequencies, e.g. magnetotellurics. The magnetometer performance enables room-temperature, unshielded magnetocardiography.

AMR Magnetometer With Digital Feedback for Space Applications

  • DOI: 10.1109/I2MTC43012.2020.9129039
  • Odkaz: https://doi.org/10.1109/I2MTC43012.2020.9129039
  • Pracoviště: Katedra měření
  • Anotace:
    In this paper, we present research and development regarding a novel concept of a digitally compensated, low-noise magnetometer based on anisotropic magnetoresistance sensors that is suitable for space applications. The central idea of the design is to reduce the number of precise analog components while using the digital signal processing power available in a modern microcontroller. Our most recent effort targeted lowering power consumption and overall improvement of the parameters. Only commercial off-the-shelf components are used in the concept reported here, keeping costs manageable even for low-budget CubeSat missions. The principle of operation is presented in detail, along with a full characterization of a real instrument, including its noise, linearity, and temperature stability. The results of Total Ionizing Dose testing at a gamma-ray irradiation facility are discussed at the complete magnetometer and part levels; they suggest the instrument's good potential.

High Dynamic Range Digital Fluxgate Magnetometer

  • DOI: 10.1109/SENSORS47125.2020.9278852
  • Odkaz: https://doi.org/10.1109/SENSORS47125.2020.9278852
  • Pracoviště: Katedra měření
  • Anotace:
    In this paper, we present an advanced fully digital solution of a fluxgate magnetometer with both demodulation and compensation carried out by a low-cost field programmable gate array (FPGA). For feedback operation, we avoid using a costly precise digital-to-analog converter, instead employing an FPGA to generate a hybrid pulse width modulation sigma-delta signal. Even with only a few additional components to process such signals, we were able to achieve excellent linearity, noise, and stability, as supported by measurements. On the front-end side only one pick-up signal preamplifier is necessary, greatly reducing the number of analog circuits needed. This can be an advantage in radiation-hazard sites like space missions, as there are fewer radiation-susceptible parts that can degrade. We provide a short description of the entire setup—electronics, fluxgate sensor construction, and final power budget—and a parameter summary in the conclusion.

1 pT-noise fluxgate magnetometer design and its performance in geomagnetic measurements

  • DOI: 10.1109/I2MTC.2019.8826956
  • Odkaz: https://doi.org/10.1109/I2MTC.2019.8826956
  • Pracoviště: Katedra měření
  • Anotace:
    We present a design of a low-noise, fundamentalmode, orthogonal fluxgate magnetometer with amorphous wires. The noise obtained in open-loop was as low as 5, 2 and 0.8 pT/√ Hz at 0.1, 1 and 5 Hz, respectively. As the instrument is a self-contained device, powered with batteries, we were able to run a series of geomagnetic measurements and compare them to a low-noise observatory magnetometer. The geomagnetic measurements were performed at the SANSA Space Science facility in Hermanus, South Africa. The offset drift is still an issue, however we show that the instrument is fully suitable for measurements down to 10 mHz. With numeric compensation of the offset drift, sub-mHz measurements are possible. As the instrument is non-cryogenic and portable, more applications, such as magnetotellurics or an unshielded magnetocardiography with a gradiometric sensor, are foreseen.

A Digitally Compensated AMR Magnetometer

  • DOI: 10.1109/TMAG.2018.2873235
  • Odkaz: https://doi.org/10.1109/TMAG.2018.2873235
  • Pracoviště: Katedra měření
  • Anotace:
    This paper considers the possibilities of using digital feedback for precise anisotropic magneto-resistance (AMR) magnetometers using commercial off-the-shelf (COTS) components. This paper presents the full characterization of a real instrument, including its noise, linearity, stability, and power consumption.

High dynamic range fluxgate magnetometer

  • Pracoviště: Katedra měření
  • Anotace:
    Possibilities of achieving high dynamic range for fluxgate magnetometer are discussed. In order to measure small variations in a large bias, a variometric arrangement can be used instead. ADC then digitizes only small range of the magnetometer as most of measured magnetic field is removed by a precise compensation system.

Testing and application of an integrated fluxgate sensor DRV425

  • DOI: 10.2478/jee-2018-0064
  • Odkaz: https://doi.org/10.2478/jee-2018-0064
  • Pracoviště: Katedra měření
  • Anotace:
    The article presents testing of a miniature fluxgate sensor developed and manufactured by Texas Instruments as well as an application of the sensor in a compact magnetic field probe with USB interface and LabView based software. Several basic properties of the sensor were evaluated and compared with the datasheet specifications. Offset stability measurements have indicated some possible problems for applications that require very high DC and low-frequency precision.

Za stránku zodpovídá: Ing. Mgr. Radovan Suk