Towards Affordable Home Health Care Devices Using Reconfigurable System-on-Chip Technology

Abstract

Multi-channel data acquisition (DAQ) is a crucial component in digital instrumentation and control. It typically involves the sampling of multiple analog signals, and converting them into digital formats so that they can be processed either on-board or externally. In either cases, DAQ systems also involve microprocessors, microcontrollers, digital signal processing, and/or storage devices. Multi-channel DAQs, which utilize some sort of processing for simultaneous input channels, are needed in home health care monitoring devices. In this chapter, a low-cost real-time multi-channel Analog Signal Acquisition and Processing (ASAP) system is presented. It is divided into five systems. First, the Multi-channel Analog Signal Acquisition system is used to acquire multi-channel real-time analog signals. Second, Archiving system stores the acquired data into a Flash memory or SDRAM. Third, the Digital Signal Processing Unit performs digital signal processing. Fourth, the Frequency Deviation Monitoring (FREDM) system detects any change in input channels’ frequencies. Finally, the Heterogeneous Maximal Service (HMS) Scheduler is presented to be integrated with FREDM system. In home health care devices, storage is limited and power consumption need to be minimum. Therefore, fixed sampling rate is not the optimal solution for multi-channel human body data acquisition. Hence, heterogeneous sampling rates are identified for each channel, and optimized for best data quality with minimal storage requirement and power consumption. The fidelity of the ASAP system is increased by using reconfigurable chip technology, where flexibility, concurrency and reconfiguration can be achieved in hardware. The proposed ASAP allows for the sampling of up to 32 heterogeneous signals with a single high speed Analog to Digital Converter (ADC) taking into account the performance as well. In the biomedical field, the first step of diagnose a patient is recording biomedical data. Monitoring the vital signs of the patient in acute life-threatening states or being under surgical procedures or anesthesia conditions requires online analysis and immediate visualization. If the immediate visualization is irrelevant, storage of the acquired data is needed. Electrocardiogram (ECG) devices are the most important diagnostic tools for heart patients. Respiratory problems represent one of the main causes of disease in our world. Most of research papers proposed in this field use computer-based devices to acquire signals from the human body. Moreover, there were no scheduling algorithms used. The proposed ASAP 7