IQ Freq Meas (NB-IoT)
OFDM symbol FFT has been performed on the measured data. This trace is available only for uplink signals.
shows the IQ data taken after theWhen there are multiple tones, NPUSCH IQ values shown on the IQ Freq Meas trace resemble a collection of random points concentrated around the origin as a result of the SC-FDMA modulation.
To view SC-FDMA (uplink NPUSCH) signals in the time domain, use IQ Meas.
Only the points of channels/signals selected in Composite Include are shown on this trace. The color of a point indicates which channel/signal the point belongs to. The colors of the channel/signals are shown in the Frame Summary trace.
The information on this trace comes from the data in the Measurement Interval.
The data in Time trace data after being processed by the demodulator, is a 2x2 matrix with frequency along one dimension and time along the other. In addition, each one of the points in the matrix is a complex value; therefore, there are 4 total dimensions. The choice of trace format determines which two dimensions will be on the x-y plane, and which dimensions will be overlapped, averaged, or ignored. The relevant trace formats and their corresponding view of the data are described below.
, which comes from the- Constellation, IQ - The I-Q plane is mapped to the x-y plane and each point contains both a subcarrier and a symbol-time reference. In other words, each point plotted on the complex plane came from a complex value transmitted on a specific subcarrier at a certain time.
- LogMag, LinMag, Real, Imag, Wrapped Phase, Unwrapped Phase - Subcarriers are plotted along the x-axis. All the modulation symbols transmitted on a subcarrier have been plotted above the corresponding subcarrier tick on the x-axis, in the specified format (whether it be dB magnitude or the real value of the symbol point, etc.).
See Also