This paper presents the design and the realization of a linear power amplifier with large bandwid... more This paper presents the design and the realization of a linear power amplifier with large bandwidth (15 MHz) capable of driving low impedance ultrasonic transducers. The output current driving capability (up to 5 A) and low distortion makes it suitable for new research applications using high power ultrasound in the medical and industrial fields. The electronic design approach is modular so that the characteristics can be scaled according to specific applications and implementation details for the circuit layout are reported. Finally the characterization of the power amplifier module is presented.
Punto di forza di questo testo è la grande flessibilità nell'adattarsi alle diverse esigenze ... more Punto di forza di questo testo è la grande flessibilità nell'adattarsi alle diverse esigenze didattiche. La grande attenzione riservata alle tecnologie di ultima generazione rende il testo più che mai attuale
New developments in the proton-therapy field for cancer treatments, leaded Italian physics resear... more New developments in the proton-therapy field for cancer treatments, leaded Italian physics researchers to realize a proton imaging apparatus consisting of a silicon microstrip tracker to reconstruct the proton trajectories and a calorimeter to measure their residual energy. For clinical requirements, the detectors used and the data acquisition system should be able to sustain about 1 MHz proton rate. The tracker read-out, using an ASICs developed by the collaboration, acquires the signals detector and sends data in parallel to an FPGA. The YAG:Ce calorimeter generates also the global trigger. The data acquisition system and the results obtained in the calibration phase are presented and discussed.
The different techniques used for field measurements of moisture content in the San Rocco Church ... more The different techniques used for field measurements of moisture content in the San Rocco Church in Cornaredo, Italy, were compared and discussed. The comparison considers the heterogeneous nature of the data collected, and the benefits and disadvantages of each technique tested. The results from the techniques used to measure water content in the superficial layer were in very good agreement, while the data from the techniques that were applied to test more deeply within the masonry showed greater variability because of the variability of the diffusion of water deep inside the material and the lack of established techniques to obtain the reference results from the deepest layers of the materials. Therefore, the discussion presented in this paper summarizes some of the obtained results that are useful when comparing the techniques. This comparison highlights the techniques according to their reliability and feasibility for use in the field, required surface features for the application, work conditions, current techniques and costs associated with the use of the tests.
2021 IEEE International Joint EMC/SI/PI and EMC Europe Symposium, Jul 26, 2021
In this work, a method is presented to predict the radiofrequency impedance of a practical implem... more In this work, a method is presented to predict the radiofrequency impedance of a practical implementation of a bypass network. Circuit models of both ceramic and electrolytic capacitors are introduced, whose parameters are derived from manufacturers’ specifications. Mounting inductance of capacitors is accounted for through estimates of vias and microstrips inductance. Predictions are confirmed by vector network analyzer (VNA) measurements through an incremental process of comparisons in which the number of parallel capacitances of the bypass network is progressively increased. A simple technique to remove the residual (after VNA calibration) series inductance introduced by the radiofrequency connectors used to connect the VNA ports to the printed circuit board hosting the bypass network is presented. An insight into the low-frequency behavior of ceramic capacitors of large capacitance (in the tens of microfarad range) is also offered. Measurements confirm the reliability of the lumped circuit model of the bypass network up to about 400 MHz for a printed circuit board (PCB) sized 15 cm x 11.3 cm. Above this frequency distributed phenomena and radiation cause measurements to significantly deviate from predictions. The bypass network impedance behavior is essentially described, up to the frequency limit of validity of the lumped model, by a simple but effective series circuit consisting in a large capacitance of the order of 1 mF , an inductance of the order of 0.07 nH and a resistance of the order of 0.5 mΩ.
This paper presents the design and the realization of a linear power amplifier with large bandwid... more This paper presents the design and the realization of a linear power amplifier with large bandwidth (15 MHz) capable of driving low impedance ultrasonic transducers. The output current driving capability (up to 5 A) and low distortion makes it suitable for new research applications using high power ultrasound in the medical and industrial fields. The electronic design approach is modular so that the characteristics can be scaled according to specific applications and implementation details for the circuit layout are reported. Finally the characterization of the power amplifier module is presented.
Punto di forza di questo testo è la grande flessibilità nell'adattarsi alle diverse esigenze ... more Punto di forza di questo testo è la grande flessibilità nell'adattarsi alle diverse esigenze didattiche. La grande attenzione riservata alle tecnologie di ultima generazione rende il testo più che mai attuale
New developments in the proton-therapy field for cancer treatments, leaded Italian physics resear... more New developments in the proton-therapy field for cancer treatments, leaded Italian physics researchers to realize a proton imaging apparatus consisting of a silicon microstrip tracker to reconstruct the proton trajectories and a calorimeter to measure their residual energy. For clinical requirements, the detectors used and the data acquisition system should be able to sustain about 1 MHz proton rate. The tracker read-out, using an ASICs developed by the collaboration, acquires the signals detector and sends data in parallel to an FPGA. The YAG:Ce calorimeter generates also the global trigger. The data acquisition system and the results obtained in the calibration phase are presented and discussed.
The different techniques used for field measurements of moisture content in the San Rocco Church ... more The different techniques used for field measurements of moisture content in the San Rocco Church in Cornaredo, Italy, were compared and discussed. The comparison considers the heterogeneous nature of the data collected, and the benefits and disadvantages of each technique tested. The results from the techniques used to measure water content in the superficial layer were in very good agreement, while the data from the techniques that were applied to test more deeply within the masonry showed greater variability because of the variability of the diffusion of water deep inside the material and the lack of established techniques to obtain the reference results from the deepest layers of the materials. Therefore, the discussion presented in this paper summarizes some of the obtained results that are useful when comparing the techniques. This comparison highlights the techniques according to their reliability and feasibility for use in the field, required surface features for the application, work conditions, current techniques and costs associated with the use of the tests.
2021 IEEE International Joint EMC/SI/PI and EMC Europe Symposium, Jul 26, 2021
In this work, a method is presented to predict the radiofrequency impedance of a practical implem... more In this work, a method is presented to predict the radiofrequency impedance of a practical implementation of a bypass network. Circuit models of both ceramic and electrolytic capacitors are introduced, whose parameters are derived from manufacturers’ specifications. Mounting inductance of capacitors is accounted for through estimates of vias and microstrips inductance. Predictions are confirmed by vector network analyzer (VNA) measurements through an incremental process of comparisons in which the number of parallel capacitances of the bypass network is progressively increased. A simple technique to remove the residual (after VNA calibration) series inductance introduced by the radiofrequency connectors used to connect the VNA ports to the printed circuit board hosting the bypass network is presented. An insight into the low-frequency behavior of ceramic capacitors of large capacitance (in the tens of microfarad range) is also offered. Measurements confirm the reliability of the lumped circuit model of the bypass network up to about 400 MHz for a printed circuit board (PCB) sized 15 cm x 11.3 cm. Above this frequency distributed phenomena and radiation cause measurements to significantly deviate from predictions. The bypass network impedance behavior is essentially described, up to the frequency limit of validity of the lumped model, by a simple but effective series circuit consisting in a large capacitance of the order of 1 mF , an inductance of the order of 0.07 nH and a resistance of the order of 0.5 mΩ.
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Papers by LORENZO CAPINERI