writer
544
edits
Difference between revisions of "NVGate 2021: Release note"
Jump to navigation
Jump to search
NVGate 2021: Release note (view source)
Revision as of 11:03, 27 November 2020
, 11:03, 27 November 2020no edit summary
| Line 24: | Line 24: | ||
==Increased filter order== | ==Increased filter order== | ||
The order of the filter affects the steepness of its roll-off. The higher the order, the sharper the transition between the pass band and the stop band. An example demonstrating the impact of the filter order is shown below. | The order of the filter affects the steepness of its roll-off. The higher the order is, the sharper the transition between the pass band and the stop band is. An example demonstrating the impact of the filter order is shown below. | ||
[[File:butterworth_freq_response.png|600px]] | [[File:butterworth_freq_response.png|600px]] | ||
For the high pass and low pass filters, the filter order can be selected from 1 to 40 in Office mode, and from 1 to 10 in Connected mode now. In the previous NVGate version, the maximum filter order | For the high pass and low pass filters, the filter order can be selected from 1 to 40 in the Office mode, and from 1 to 10 in the Connected mode now. In the previous NVGate version, the maximum filter order was 6. | ||
For the band pass and band stop filters, the filter order is 2*N, and N can be selected from 1 to 30 in Office mode, and between 1 to 10 in Connected mode now. In the previous NVGate version, the maximum value of N | For the band pass and band stop filters, the filter order is 2*N, and N can be selected from 1 to 30 in the Office mode, and between 1 to 10 in the Connected mode now. In the previous NVGate version, the maximum value of N was 5. | ||
== | ==Relaxed constraints on the cut-off frequency== | ||
To guarantee the stability of the filter, there are certain constraints on the value of the cut-off frequency. Compared with previous version of NVGate, such constraints are relaxed significantly now. | To guarantee the stability of the filter, there are certain constraints on the value of the cut-off frequency. Compared with previous version of NVGate, such constraints are relaxed significantly now. | ||
| Line 38: | Line 38: | ||
[[File:image_2020-11-27_095451.png|600px]] | [[File:image_2020-11-27_095451.png|600px]] | ||
For the high pass and low pass filters, the maximum value of the cut-off frequency is the input frequency range '''FR'''. The minimum value is '''FR''' / 50000 in the Office mode, and '''FR''' / 40000 in the Connected mode. In the previous version | For the high pass and low pass filters, the maximum value of the cut-off frequency is the input frequency range '''FR'''. The minimum value is '''FR''' / 50000 in the Office mode, and '''FR''' / 40000 in the Connected mode. In the previous NVGate version, the minimum value was '''FR''' / 40 for the low pass filter, and '''FR''' / 400 for the high pass filter. | ||
For the band pass and band stop filters, the low cut-off frequency ''f''<sub>low</sub> and the high cut-off frequency ''f''<sub>high</sub> need to meet the following conditions in the Office mode: | For the band pass and band stop filters, the low cut-off frequency ''f''<sub>low</sub> and the high cut-off frequency ''f''<sub>high</sub> need to meet the following conditions in the Office mode: | ||
| Line 56: | Line 56: | ||
* 0.000675 * '''FR''' ≤ ''f''<sub>high</sub> - ''f''<sub>low</sub> ≤ 0.99 * '''FR''' | * 0.000675 * '''FR''' ≤ ''f''<sub>high</sub> - ''f''<sub>low</sub> ≤ 0.99 * '''FR''' | ||
In the previous version | In the previous NVGate version, the conditions on the cut-off frequencies were: | ||
* ''f''<sub>low</sub> ≥ 0.055 * '''FR''' | * ''f''<sub>low</sub> ≥ 0.055 * '''FR''' | ||
| Line 65: | Line 65: | ||
==Improved precision== | ==Improved precision== | ||
Now, the filters are calculated in 64-bit floating point format in Office mode, and in 40-bit floating point format in Connected mode. In the previous NVGate version, the 32-bit floating point format | Now, the filters are calculated in 64-bit floating point format in the Office mode, and in 40-bit floating point format in the Connected mode. In the previous NVGate version, the 32-bit floating point format was used in both modes. | ||