Preamble Phase Err (MB-OFDM)

Menu Path: Trace > Data > Composite > Preamble Phase Err

The composite Preamble Phase Err trace shows the phase error of the preamble bursts (in degrees) in a display of (30) bursts for a Standard Preamble or (18) bursts for a Burst Preamble. The preamble type can be specified - Standard or Burst - using the parameter Preamble Type.

This trace displays all occupied bands.

As shown below, the Standard Preamble consists of (24) Packet/Frame Sync + (6) Channel Estimation symbol-times for a total of (30) symbol-times, with duration: 30 x .3125 uSec/symbol-time = 9.375 uSec. The Burst Preamble consists of (12) Packet/Frame Sync + (6) Channel Estimation symbol-times for a total of (18) symbol-times, with duration: 18 x .3125 uSec/symbol-time = 5.625 uSec.

The Start time of this trace is -9.375 uSec for the Standard Preamble or -5.625 uSec for the Burst Preamble (preamble duration), but negative because 0 time is the start of the first Header symbol-time in the Result Length (see Lengths, Intervals, and Offsets).

The value in this trace lies in the ability to view the preamble quality in detail. For example, to examine conditions of poor sync correlation but good channel estimation, or vice versa.

See Also

Available Trace Data (MB-OFDM)

Trace Problems (MB-OFDM)