Ch Impulse Response (Channel Quality)

Ch Impulse Response (Balanced) is the channel impulse response corresponding to the Ch Frequency Response. The channel impulse response is calculated for each measurement channel and is averaged over the number of repetitions of the stimulus signal specified by the Analysis Interval.

The x-axis of this trace is in units of seconds. The peak is always located at t = 0. The impulse response traces show the supported delay spread (1 / Tone Spacing).

To increase the available delay spread range, increase the number of tones while decreasing the Tone Spacing to maintain the same ratio (same stimulus bandwidth).

When RMS or RMS Exponential averaging is enabled, this trace will show the Vector (complex) averaged channel impulse response. This will drive the noise towards zero with increased average count.

The non-averaged channel impulse response is shown in the Inst Ch Impulse Response trace.

I and Q Channel Impulse Response Traces

There are also traces for I and Q that express the impulse response separately for the In Phase and Quadrature Phase components of the channel. These traces are computed from the Balanced and Unbalanced responses.