Chapter 4: Additional Functions; System Tuning; Transmitter Tuning Parameters - Avocent Emerge MPX Installer/User Manual

CHAPTER
4

System Tuning

Transmitter tuning parameters

Controls provided on the Tuning Parameters web page, illustrated in Figure 4.1, allow you to fine
tune the operation of your extension system.
To properly tune the video data rate settings, it is helpful to understand that the bandwidth capacity
of the wireless media LAN is continually shifting rather than constant. Stated in another way, the
capacity of the LAN to carry data expands and contracts as moving objects interact with the radio
transmission. The majority of LAN bandwidth is required for transmission of video data, which
consists of real-time video (data that is being sent for the first time) and retransmitted data. Under
ideal conditions, the LAN is filled real-time data. Under adverse conditions, as may result from RF
interference, receivers may capture only a portion of the real-time data. In response, those receivers
may request retransmission of the missing data. The transmitter will attempt to service these
retransmission requests even as even as real-time data is being sent to other receivers.
To ensure an acceptable video frame rate and image quality, the transmitter is able to dynamically
detect shifting conditions and alter its processing of real-time and retransmitted data as needed to
accommodate for these conditions. To allow increased headroom for retransmitted data, real-time
data can be more highly compressed (within user-defined limits). Likewise, the amount of
retransmitted can be metered within pre-defined bounds to prevent isolated obstructions from
affecting non-obstructed receivers.
The default tuning parameter values are designed to maintain a reasonable balance between image
quality and frame rate across all receivers. Based on the needs of your particular application, it may
be of value to tune these parameters. The following table provides you with additional information.
Additional Functions
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