IQ Meas Time (MB-OFDM)
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The composite trace shows the data results for all occupied bands, where the magnitude of the IQ time differences between an ideal signal and the measured signal appear on the y-axis. If the trace reports DATA? instead of data, see Trace Problems.
The trace appears as a series of vertical lines where each line represents a burst of 122 subcarriers (OFDM Symbols) across the symbol-times appearing in the Measurement Interval setting. For example, if the Measurement Interval is set for 12 symbols-times, the trace x-axis displays 12 vertical lines. The vertical lines are ordered left-to-right by a Time-Frequency Code (TFC Transport Format Combination). For example, for TFC=1, the hopping sequence is Low-Mid-High-Low-Mid-High, thus, the vertical lines are ordered Low-Mid-High-Low-Mid-High.
The Start and Stop points on the x-axis depend on the Measurement Offset setting. For example, if the = 12 symbol-times and the = 0 symbol-times, then the x-axis Start = 0 and Stop = 11. If the = 12 symbol-times and the = 6 symbol-times, the Start = 6 and Stop = 17. The examples above assume the Result Length is 18 symbol-times are greater. To learn more, see Lengths, Intervals, and Offsets).
Setup Example
Let Result Length = 12 | Measurement Offset = 0 | Measurement Interval = 6 | TFC = 1. For these conditions, this trace displays (6) vertical lines 0 to 5 in sequence Low-Mid-High-Low-Mid-High with each vertical line representing a burst of 122 subcarriers (OFDM Symbols) -61 to -1 and +1 to +61. For trace identification, the pilot and guard symbols are colored differently than the data symbols. The illustration below displays the (6) burst sequence for this example.
See Also
Available Trace Data (MB-OFDM)
