MSP430FR6043: F1 to F2 Sweep模式怎么确定合适的F1和F2频率？

您好

已经收到了您的案例，调查需要些时间，感谢您的耐心等待

您好，

       将“F1”和“F2”分别设置为传感器在 kHz 中的标称频率的低端和高端（例如，对于 200kHz 的传感器设置为 180 和 230）。

       然后在进行frequency sweep后调节此参数。

      Quick Start Guide for Gas Flow Meter 文档中Figure 18是一种大致确定F1和F2选择范围的方法。  您还需要调整F1和F2的频率，以便进行最终配置。

感谢解答。
我查资料的时候看到这么一段描述：

The USS_A module can be used in gas meter application. The major difference between the USS and USS_A module is the Sequencer for Acquisition, Programmable Pulse Generator, and Physical Interface (SAPH module). SAPH: Consists of an extended pulse generator, a low-impedance output driver, an input multiplexer, an acquisition sequencer and external bias terminals. The SAPH_A module can generate Multi tone. The output pulses consist of multiple phases. The multi tone feature is important for the absTOF calculation in gas meter. The generated excitation signal’s binary pattern is used as a filter to filter out noise on the UPS/DNS ADC capture signal before processing the Hilbert transform. This multi tone feature lowers the impact of noise signal. And make the ADC approach successfully used in the Gas meter application。

我试着用multi tone和多音频激励等关键词搜了下，但是相关的介绍很少。我想详细了解下“This multi tone feature lowers the impact of noise signal”的技术原理，请问能提供些参考资料吗？谢谢。

您好，

   请参考  Ultrasonic sensing of gas flow white paper 

感谢您提供的资料，我已经全部看完。有两个问题想请教下：
1、文档里提到“Adjust the programmable gain amplifier (PGA) setting to make the amplitude of the received signal
±800 analog-to-digital converter (ADC) counts”，我这边的换能器在6043的开发板上测试，USS中设置的增益是0.1db，ADC捕获的幅度最大值已经有1800，那我是否需要降低增益，使ADC幅值降低到±800左右，还是说ADC幅值只要不失真，大点也没关系？

2、您答复中提供的文档中对多音激励（multi excitation）的描述还是稍微简略了一点，我希望能有像TI在解释计算DTOF技术时提到的相关算法时，提供了相关的原理性的文档：
3 References
1. National Physical Labs (NPL), Underwater Acoustics, Technical Guides - Speed of Sound in Pure Water
resource.npl.co.uk/.../speedpw.pdf
2. D.Marioli, C.Narduzzi, C.Offelli, D.Petri, E.Sardini, A.Taroni, Digital time of flight for ultrasonic sensors, IEEE
Transactions on Instrumentation and Measurement, Vol. 41, No. 1, February 1992
3. Charles Knapp, Clifford Carter, The generalized correlation method for estimation of time delay, IEEE
Transactions on Acoustics, Speech and Signal Processing, No. 4, August 1976
4. A Comparison of Time Delay Estimation Methods for Periodic Signals, Travis Wiens, Stuart Bradley, IEEE
Transactions on Instrumentation and Measurement, Vol. 41, No. 1, February 1992

了解相关原理有助于我配置相关参数，更明确的测试换能器的性能。如果没有相关的文档的话，希望您能提供下跟多音激励相关的技术原理的资料搜索和查阅方向。谢谢。

您好，

     1 降低到±800左右

     2 没有更多的原理性的介绍，multitone信号在测量方面有广泛的应用。

       Universal Multifrequency Tone Detector (UMTD) Algorithm User's Guide