Optimizing the Switching Speed of the Current Probe Utilizing the FPGA for Input Signal Processing

The next-generation mobile networks open the doors for the new industry-oriented applications that utilize the new group of telecommunication technologies known as the low-power wide area (LPWA) technologies. In the massive machine-type communication (mMTC) scenarios where the performance-limited and energy-constrained devices are deployed, the operational lifetime is one of the most important parameters. Therefore, over the recent years, the energy efficiency and correct implementation of the power saving modes at the side of machine-type devices (MTDs) got momentum. In this paper, we introduce the improved prototype of the current probe capable to measure the current consumption of the LPWA communication devices working in both licensed and license-exempt frequency spectrum. The increased speed for range switching while measuring was done by utilization of the field programmable gate array (FPGA). The current probe with enabled fixed mA range proved to be very useful for basic waveforms as it could sample and store frequencies up to 250 Hz, which should be more than enough for most of the Internet of Things (IoT) sensors' current consumption changes. We also report the possible drawbacks related to the utilization of the FPGA and auto-ranging.