Sodera: Spectrum Analysis

Sodera has the option to sample the 2.4 GHz RF spectrum at the Sodera unit antenna connector. The spectrum data represents the Received Signal Strength Indicator (RSSI) and is automatically saved when the capture is saved.

The spectrum data is synchronized in time to the received packets and is displayed in the Coexistence View 2.4 GHz Timeline when Show Spectrum is selected in the Spectrum menu on the Coexistence View. The spectrum power level is shown as a "heat map" behind the timeline packets. The "heat map" appears in shades of blue with darker blues representing higher power levels and lighter blues representing lower power levels (white represents the lowest power level). The darkest shade of blue represents -15dBm and above, while white represents -100 dBm and below.

Note: Too strong of a signal level is detected and noted in the Events Log pane. See "Set in Target: Hardware Signal Too Strong Indication" for more information.

Spectrum data appearing in the Coexistence View Timeline that is not synchronized to a packet may indicate the presence of RF interference. Interference has the potential to degrade the Bluetooth signal.

The spectrum can be sampled at 20, 50, 100, or 200 microseconds. The Spectrum option and sample rate is set in the Capture Options... of the Options menu. Refer to "Menu" for information on capture settings. Smaller sample rate will cause an increase in memory used. However, identifying potential sources of interference may require more samples to avoid missing a signal.

Note: For Spectrum sample intervals less than 200 microseconds, the Sodera unit must be connected to a computer.

The spectrum data is saved automatically when the capture is saved. The saved spectrum data file has the file extension .swsd with the same basename as the .cfa file and in the same directory. (See "Changing Default File Locations" for information on default file locations.)

Currently, if a user opens a capture file and chooses to save the capture under a different name, a new.swsd file will not be created (this will change in an upcoming release).

When copying capture files (.cfa, .scap, etc.) to a different directory, the user must also copy the spectrum data file (.swsd). If the spectrum data file is not present at the time the capture file is opened, spectrum data will not be available in the Coexistence View.

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