Codogram Display
This view provides a history of the spectrum. The codogram plot rises over time until it fills the graphical section of the display. Your most recent data appears at the bottom of the display, and your oldest data (several minutes ago to several hours ago, depending on your settings) appears at the top of the display. In this way, you can clearly see the changes in power that occur over a period of time. You can use it to:
The W-CDMA or W-CDMA (with HSDPA) Tx analyzer Codogram screen is divided into 3 sections in the Zoom view (default) and 4 sections in the Full view as follows:
The Update Interval is the interval, measured in whole seconds, between successive records displayed on the codogram. In other words, if you set the update interval to 5 seconds, the codogram display will not update until the after the first complete measurement following a gap of five seconds. Alternatively, you can set the update interval to provide the maximum data collection speed by pressing [Max Speed], or by setting the update interval to 0 (zero) seconds.
- Zoom and Full views: The lower-right graph (Code Domain Trace view) shows the power in all 512 OVSF (Orthogonal Variable rate Spread Factor) Code Channels. For display details, refer to."Multiple-View Display"
- Zoom view: The left graph (Codogram view) provides a display of data captured over time. The OVSF codes are shown on the x-axis and correspond to the light blue highlight on the Code Domain Trace view. The OVSF codes selected for your Zoom View are determined by the Position setting, which sets the lowest (or left) OVSF code, and by the Width setting, which sets the number of OVSF codes displayed. For example, with Position set to 400, and Width set to 32, your Zoom View will show codes 400 to 431, that is, from Position 400 for a Width of 32 codes.
- You can change the time interval to allow longer spectrum history. The color corresponds to the OVSF channel strength.
- Full view: The top-left graph (Codogram view) shows the power in the first half of the OVSF channels (SF512 channels 0 - 255). The lower-left graph shows the power in the other half of the channels (SF512 channels 256-511). Both graphs provide a display of data captured over time.
- You can change the time interval to allow longer spectrum history. The color corresponds to the OVSF channel strength.
- Zoom and Full views: The top-right graph (Color Legend) provides a color vs. power legend to help you interpret the power level in the Codogram.
NOTE: It is not always possible for the analyzer to match the update interval you specify. It is possible, for example, to set your update interval to zero seconds (the maximum speed), and then to find that the analyzer can not update any faster than once every two seconds.
The frequency indicator is at the bottom right corner of the screen, the time reference indicator at the bottom left. For each indicator the text indicates which reference you have chosen. A green LED indicates a locked condition. A red "X" indicates an unlocked condition.