FPGA-Based Adaptive Data Acquisition Scheduler-on-Chip (SchoC) for Heterogeneous Signals
Data acquisition (DAQ) is a crucial component in instrumentation and control. It typically involves the sampling of multiple analog signals, and converting them into digital formats so that they can be processed. DAQ systems also involve microprocessors, microcontrollers, digital signal processing, and/or storage devices. Many multi-channel DAQs, which utilize some sort of processing for simultaneous input channels, are found in various applications. In this research, for heterogeneous multi-channel signals, different sampling rates are identified for each channel, and optimized for best data quality with minimal storage requirement. Accordingly, power consumption and transmission times can be reduced. The fidelity of the proposed Scheduler-on-Chip (SchoC) is increased by using reconfigurable chip technology, where flexibility, concurrency, speed and reconfiguration can be achieved in hardware. Therefore, SchoC can be utilized in various real world applications especially hazardous environments, or for remote architecture reconfiguration, while keeping the cost of the device low. Preliminary performance evaluations show improvements in the speed and memory requirements of the proposed SchoC over a comparable software-based scheduler.
The proposed SchoC can be utilized in many applications since different applications need to schedule multi-rate tasks on a single core processor. The proposed SchoC can be used in a low cost, high performance multi-channel DAQ system for custom sensing applications which have a matrix of different analog sensors. Alongside with analog sensors (voltage, current or charge output), quasi-digital sensors and transducers (frequency, period, PWM output) can use the proposed SchoC. Moreover, in the environmental measurements, the operational satellite synthetic radar was used to acquire different data at different frequencies in order to estimate the soil moisture in different sites on the earth. The system needs to acquire many signals within a short period of time due to the uncontrollable changing site conditions. In addition, it can be used in a versatile instrument that can be the base of developing a spectroscopic imaging.