A Low-Cost VLSI Architecture for Robust Distributed Estimation in Wireless Sensor Networks

A robust distributed estimation scheme for fusion center in the presence of sensor faults via collaborative sensor fault detection (CSFD) was proposed in our previous research. The scheme can identify the faulty nodes efficiently and improve the accuracy of the estimates significantly. It achieves very good performance at the expense of such extensive computations as logarithm and division in the detecting process. In many real-time WSN applications, the fusion center might be implemented with the ASIC and included in a standalone device. Therefore, a simple and efficient distributed estimation scheme requiring lower hardware cost and power consumption is extremely desired for fusion center. In this paper, we propose the efficient collaborative sensor fault detection (ECSFD) scheme and its VLSI architecture. Given the low circuit complexity, it is suitable for hardware implementation. The circuit of ECSFD contains 22589 gates and requires a core size of 571 × 559 μm² by using TSMC 0.18 μm cell library. Simulation results indicate the accuracy of the estimates obtained from the ECSFD is better than that obtained from a conventional approach.