A pulse sensor interface design for FPGA based multisensor health monitoring platform

Abstract

In the 21st century, IoT (Internet of Things) technology is making daily life more convenient via heterogeneous smart devices through seamless connectivity. Tens of billions of new IoT low-end devices are coupled with sensors and are connected to the Internet with an open source operating system, with limited memory, limited computational power, and limited power supplies.1‒4 For IoT devices and platforms of CPUs (central processing units), embedded GPUs (graphics processing units), and FPGAs (field-programmable gate arrays), the cost, power, performance, and volume constraints have to be tradeoff.5,6 The architecture of the FPGA makes it possible to implement any combinational and sequential circuits, which can run independently at different frequencies than the microcontroller. It can be reconfigured into a simple logic function, a master controller, and a soft processor. CAD tools or Hardware Description Languages (HDL) such as VHDL and Verilog HDL are used to program the FPGA. The survey in7 shows low-power optimized FPGAs can enhance the computation of several types of algorithms in terms of speed and power consumption in comparison to microcontrollers of commercial sensor nodes. In past years, sensor nodes based on the FPGA and CPLD platform have been proposed to be IoT low-end devices.8,9 The FPGA-based platform is critical for producing an inexpensive early validation of the platform design. An ultra-low-power and reliable FPGA is a promising solution for IoT applications. An FPGA-based edge device for IoT was proposed for dedicated hardware.8 The proposed stack can be implemented on all IoT devices avoiding the battle for the wireless standard. The reconfigurable sensor interface for wireless sensor networks in an IoT environment was proposed in.9 The core controller adopts a complex programmable logic device (CPLD) that can read data in parallel and in real time with high speed on multiple different sensor data. Such a trend has prospects of becoming integrated into biosensor and FPGAs platform in health care systems.10‒12 The biosensors integrated with the FPGA platform can monitor and measure the human body temperature, heart rate, and respiratory rate with an accuracy up to 96%. In,11 fully digital time-domain temperature sensors driven by five pulse-generators are designed and implemented in the FPGA platform. An energy efficient hardware model was implemented on the FPGA,12 This model is used to compress and reconstruct body vital signs data, for example, EEG and ECG, based on discrete wavelet transform (DWT). These research projects contribute to the advancement of the engineering field because it proves that the IoT–based smart healthcare network can be built efficiently with FPGA devices and will enhance the health care of the user.