NIWLANA_RESULT_DSSS_DEMOD_QUADRATURE_SKEW_STANDARD_DEVIATION
- Updated2023-02-21
- 1 minute(s) read
| Data Type: | float64 |
| Access: | read only |
| Functions: | niWLANA_GetScalarAttributeF64 |
| Description: | Returns the standard deviation of quadrature skew estimates. This value is expressed in degrees. Quadrature skew is the deviation in angle from 90 degrees between the in-phase (I) and quadrature-phase (Q) signals. Refer to the Quadrature Skew help topic for a graphical representation of the quadrature skew. Note: If the magnitude of the carrier or the sample clock frequency offset is greater than 25 ppm, I/Q gain imbalance magnitude is greater than 3 dB, and quadrature skew magnitude is greater than 15 degrees, the estimates of these impairments may be inaccurate. Note: Quadrature skew cannot be measured for signals with differential binary phase-shift keying (DBPSK) modulation. The DBPSK modulation corresponds to a data rate of 1 Mbps. The Quadrature skew measurement may fail for other modulation schemes, for example, differential quadrature phase-shift keying (DQPSK) and 8-PSK, if there are not enough constellation points in all quadrants of the I/Q phase plane. The DQPSK modulation corresponds to data rates of 2 Mbps, 5.5 Mbps, and 11 Mbps, and the 8-PSK modulation corresponds to data rates of 22 Mbps and 33 Mbps. |