公开(公告)号：US20030179820A1

公开(公告)日：2003-09-25

申请号：US09972558

申请日：2001-10-08

Applicant: Microchip Technology Inc.

Inventor： Thomas J. Bombard

IPC: H04Q001/20 ,  H04B003/46

CPC classification number: G01R23/16

Abstract: A spectrum analyzer that may be implemented by a simple microcontroller that does not have a hardware multiply function is disclosed. The spectrum analyzer of the present invention utilizes at least five frequency bins. The input signal is sampled at four times the bin frequency. The input signal is sampled at twice the Nyquist rate, which results in symmetries in the sin(wn) and cos(wn) functions. These symmetries allow the in-phase and quadrature components of the input signal to be calculated by add, ignore or subtract operations instead of the more complex multiplication and integration operations. Accordingly, the energy for each bin may be calculated with a minimum number of multiply operations. Because the number of multiply operations have been significantly reduced, these multiply operations may be performed by software instead of hardware. As a result, the spectrum analyzer may be implemented with a simple processor that does not have a hardware multiply. Another frequency bin is added by oversampling the highest frequency. A low pass filter is used to eliminate the effect of aliasing on the other frequency bins. A simple processor can still handle a bin that has been processed in this manner. As a result, at least five frequency bins may be processed by a spectrum analyzer implemented on a simple processor.

Abstract translation: 公开了可以由不具有硬件乘法功能的简单微控制器实现的频谱分析仪。 本发明的频谱分析仪使用至少五个频率分
组。 输入信号以四倍的频率采样。 输入信号以奈奎斯特速率的两倍采样，这导致sin（wn）和cos（wn）函数中的对称性。 这些对称性允许输入信号的同相和正交分量通过加法，忽略或减法运算而不是更复杂的乘法和积分运算来计算。 因此，可以用最小的乘法运算来计算每个仓的能量。 由于乘法运算的数量已经大大减少，所以这些乘法运算可以由软件代替硬件执行。 结果，频谱分析仪可以用不具有硬件乘法的简单处理器来实现。 通过过采样最高频率来添加另一个频率仓。 低通滤波器用于消除混叠对其他频率仓的影响。 一个简单的处理器仍然可以处理已经以这种方式处理的bin。 结果，至少五个频率仓可以由在简单处理器上实现的频谱分析仪处理。