高级检索

    一种改进的基于FPGA的32位对数变换器的设计与实现

    Design and Implementation of an Improved FPGA-Based 32-Bit Logarithmic Converter

    • 摘要: 对数变换器是对数乘法器的重要组成部分,它们以精度换取更快的速度.设计并实现了一种基于FPGA的32位二进制对数变换器,主要由先导“1”检测电路、移位逻辑和误差校正电路组成,通过有效的误差校正算法提高了计算精度;给出了一种新的4位、16位和32位的基于FPGA的并行先导“1”检测电路PLOD,在保持低延时的同时,减小了先导“1”检测电路的功耗和面积;改进了现有的6-域校正算法,在提高精度的同时保持了硬件电路的规整性,降低了系统复杂度及面积和功耗开销;分两站流水实现校正操作,提高了系统的吞吐率;改进后的校正电路将对数操作的最大误差由30%降低到20%,区域1的平均误差大幅度降低.

       

      Abstract: Logarithmic converter is one of the most important components of logarithmic multipliers, which trades the computing precision for speed. It can be used in real-time applications, such as digital signal processing, which can tolerate loss in precision to a certain extent. In addition, hardware implementation of algorithms is another most important way to accelerate the execution of algorithms. In this paper an improved 32-bit binary logarithmic converter implemented in FPGA is presented. It is mainly composed of leading one detector, shifting logic and error correction circuit. Fast 4, 16, and 32-bit leading-one detector circuits are designed to obtain the leading-one position of an input binary word in parallel, which reduces the area and power-consumption estate while keeping the low delay. In addition, an improved 6-region algorithm is developed to reduce the maximum percent errors from current 30 percent to 20 percent, which greatly decreases the average error of the first region. The error correction circuit is implemented in double pipelined cycles with a bit more components to enlarge the throughput of the system; it maintains the regularity to reduce the complexity, area and power consumption of the system, while improving the precision of the computing. The design makes it possible to accelerate the processing of time-critical applications while keeping high precision.

       

    /

    返回文章
    返回