ABSTRACT

Digital filters with variable bandwidth can be used for a variety of applications. Arbitrary change in the bandwidth of a digital Finite Impulse Response (FIR) filter can be acquired using sampling rate converters (SRCs). In this paper, a SRC is proposed which is generated from Pascal structure, a fractional delay filter having low hardware complexity and high modularity. A low-pass filter having a single bandwidth sandwiched between two SRCs can contribute multiple bandwidths in such a way that each bandwidth is an arbitrary variation of the original bandwidth. A two-stage frequency response masking (FRM) approach is used for the hardware efficient design of the original low-pass filter. A low complexity and high modularity novel design for a continuously varying bandwidth of a digital FIR filter is proposed in this paper using the proposed SRC. The modularity of the Pascal structure can be used to control both pass band ripple as well as stop band attenuation of the continuously variable bandwidth FIR filter design. Different communication standards in a software-defined radio (SDR) channelizer is realised using the proposed design of continuously variable bandwidth filter.

摘要

具有可变带宽的数字滤波器可用于多种应用。可以使用采样率转换器 (SRC) 获取数字有限脉冲响应 (FIR) 滤波器带宽的任意变化。本文提出了一种由Pascal结构生成的SRC，一种硬件复杂度低、模块化程度高的分数延迟滤波器。夹在两个 SRC 之间的具有单个带宽的低通滤波器可以以每个带宽都是原始带宽的任意变化的方式贡献多个带宽。两级频率响应掩蔽 (FRM) 方法用于原始低通滤波器的硬件高效设计。本文使用所提出的 SRC 提出了一种低复杂度和高模块化的新颖设计，用于数字 FIR 滤波器的连续变化带宽。Pascal 结构的模块化可用于控制连续可变带宽 FIR 滤波器设计的通带纹波和阻带衰减。使用所提出的连续可变带宽滤波器的设计来实现软件定义无线电（SDR）信道器中的不同通信标准。