Rohde and Schwarz FPH-K15 - Interference Analysis Option for FPH

The R&S FPH-K15 interference analysis and R&S FPH-K16 signal strength mapping options are great tools for analyzing and locating ambiguous signals or interferers.

FPH-K15: When analyzing, long-time spectrogram recording allows up to 999 hours of on-air activity to be captured; the recording duration depends on the recording interval setting. The recorded data can be analyzed on the device or with the R&S InstrumentView software.

FPH-K16: The signal strength mapping displays a pictorial view of the signal power level on an indoor or outdoor map. The color indicator provides a good estimation of the signal coverage in a particular area or where the interferer or intended signal is most likely located.

Signal Strength Mapping

Display of the interferer signal strength on the map with the R&S®FPH-K16 signal strength mapping option

Triangulation

Locating a signal with the R&S®FPH-K15 interference analysis option

Spectrogram

Equipped with option R&S FPH-K15, you can view measurement results in a spectrogram.

The spectrogram result display shows the spectral density of a signal in the frequency domain and over time simultaneously.

Like other result displays, the horizontal axis represents the frequency span. The vertical axis represents time. Time in the spectrogram runs chronologically from top to bottom. Therefore, the top of the diagram is the present. A third dimension shows the amplitude for each frequency by mapping different colors to every power level. The result is therefore a two-dimensional diagram.

The color the R&S Spectrum Rider assigns to a power level that was measured depends on:

• Color table
• Spectrogram reference level
• Spectrogram level range

The spectrogram consists of horizontal lines, each of one pixel height, which is called frames. In the default state, a frame is added to the spectrogram after each sweep. This means that the amount of data in a frame depends on the sweep time. As the spectrogram in the R&S Spectrum Rider runs from top to bottom, the outdated timeline moves down one position, so that the present frame is always on top of the diagram.

Therefore, the sequence of frames is chronological.

By default, the spectrogram result display consists of two windows. The upper window shows the measured spectrum as a trace line. The lower window shows the measurement results in a spectrogram. The chronological information in the spectrogram is restricted by the internal memory of the R&S Spectrum Rider. The R&S Spectrum Rider stores 1024 frames or spectrums that have been measured in its memory. As the height of the display is smaller, some of the data becomes invisible after a time.

Triangulation

With option R&S FPH-K15, the R&S Spectrum Rider is able to locate the source of interference using the triangulation method.

To perform triangulation, you have to create at least two or three geotags with azimuth information. After creating the geotags, display them on the map. Based on these geotags, the R&S Spectrum Rider calculates the point at which the azimuth lines of the geotags intersect. This intersection point represents the source of the interference.

If necessary, you can assign a different azimuth for the current position of GPS coordinates.