Signal Analysis - CIR - Echo Profile Plot
Last Update: Apr 25, 2024

CIR - Echo Profile Plot


Web UI Icon

Signal Analysis - CIR/Echo Profile plot

Supported Devices

Broadcast Standards


Availble Tools

  • Markers
  • Cross Ba
  • Manual Scale
  • MIN-MAX-AVG Hold
  • CIR Ref and Monitor
  • SFN ID Markers
  • TxID Explorer


Signal Analysis - Channel Impulse Response (CIR) or Echo Profile plot


The Receiver provides convenient tools for signal channel analysis. A Channel Impulse Response (CIR) plot with a set of tools is most valuable for monitoring and measuring the signal echoes in multipath environment or signals from multiple transmitters working in SFN mode. In case of sampling the signal directly at a transmitter system output, the CIR plot can be used for estimation of reflected power caused by possible mismatch between the amplifier output and antenna system.

The Receiver allows performing channel estimation in two distinctive modes for ATSC 3.0 (Device Settings):

  • SFN Multiple channels mode is a recommended mode for multipath environment that is typical for SFN and in-field measurements;
  • Single Channel is a preferred mode for channel estimation in application where no multipath echoes or SFN transmission are expected. It is also recommended for measurements directly at a transmitter system output including a band-pass filter response.

The CIR plot's highlighted area corresponds to the current Guard Interval (GI) length set as the signal modulation parameter. By default, the echoes are positioned inside the GI length in the way of maximizing their "positive" contribution. A user can assign any of the echo peaks as a reference by selecting CIR Ref and Monitor option from the available tools. The selected peak will be positioned at the center of the plot.

ATSC 3.0 TxID and DAB TII labels are assigned to the correspondent peaks if the transmitter identification is included in the signal. In order to prevent assigning TxID or TII to multiple echoes (copies) of the same signal, a user can define a detection threshold level for the echo identification with SFN ID Markers tool.