10.2. RFFT 性能测试
10.2.1. 概述
rfft性能测试主要测试了DSP进行rfft变换的性能
10.2.2. 程序设计
软件生成生成几个幅值和相位不同的正弦波并叠加生成一个波形，然后使用rfft变换求出幅频特性数据，几个正弦波如下所示:
幅值11，频率8
幅值19，频率17
幅值13，频率24
10.2.3. 硬件设置
无特殊设置
10.2.4. 性能优化
segger已经默认开启O3优化
10.2.5. 运行现象
当工程正确运行后，串口终端会输出采样点数，以及幅频特性的数据，以及每一个单元的运行时间，并在最后输出PASS或者ERROR NUM。
串口输出如下所示：
Rfft demo: 64.
total times:5133 tick.
------------------------------------
DC component amplitude:5.000004.
Frequency:8.000000, Amplitude:11.000010.
Frequency:17.000000, Amplitude:18.999992.
Frequency:24.000000, Amplitude:13.000002.
------------------------------------
Rfft demo: 128.
total times:7956 tick.
------------------------------------
DC component amplitude:4.999997.
Frequency:8.000000, Amplitude:11.000002.
Frequency:17.000000, Amplitude:18.999996.
Frequency:24.000000, Amplitude:13.000004.
------------------------------------
Rfft demo: 256.
total times:25266 tick.
------------------------------------
DC component amplitude:4.999996.
Frequency:8.000000, Amplitude:11.000001.
Frequency:17.000000, Amplitude:19.000000.
Frequency:24.000000, Amplitude:13.000004.
------------------------------------
Rfft demo: 512.
total times:37868 tick.
------------------------------------
DC component amplitude:4.999998.
Frequency:8.000000, Amplitude:11.000000.
Frequency:17.000000, Amplitude:19.000000.
Frequency:24.000000, Amplitude:13.000000.
------------------------------------
Rfft demo: 1024.
total times:122305 tick.
------------------------------------
DC component amplitude:4.999998.
Frequency:8.000000, Amplitude:11.000000.
Frequency:17.000000, Amplitude:19.000000.
Frequency:24.000000, Amplitude:13.000000.
------------------------------------
PASS.
----------------END--------------------
性能如下表所示：
采样点 |
64 |
128 |
256 |
512 |
1024 |
|---|---|---|---|---|---|
DSP rfft |
5133 |
7956 |
25266 |
37868 |
122305 |