Table Of Contents
Expected Peak
Specifies the expected peak signal, as a fraction of the full-scale signal to acquire or generate.
1.0 = 100%, 0.5 = 50%. NI-USRP uses this value to scale 8-bit data transferred over the bus. USRP devices support 16-bit values, which allow a full-scale binary data range from -32,768 to 32,767. When using an 8-bit sample width, transfer the 8-bit samples that contain the significant values of your signal. Use this property to specify the fraction of the full-scale range you expect your signal to occupy so that you transfer the most significant bits.
Data type:
Default: 1.0
Long Name: Configuration:Advanced:Expected Peak
Class: NI-USRP
Permissions: Read/Write
| Channel-based | No |
| Resettable | Yes |
Determining Expected Peak
Use the following equation to determine the value for the Expected Peak property:
Expected Actual Signal Range/Full-Scale Range = Expected Peak Property Value
For example, if your input signal range is -128 to 127, the expected peak, as a fraction of full-scale, is 0.00390625. If you set the Expected Peak property to 0.00390625 and the Sample Width property to 8-bit, NI-USRP transfers the lower 8-bits of data across the bus, which preserves the full dynamic range of the signal. If you set the Expected Peak property to the default value (1.0), only the upper 8-bits are transferred across the bus, which results in a signal loss.