You are here > Software > IQ Data File Analysis

Introduction

This option is used to analyse a station's signal over a period of many hours or even days. An example of this usage is the analysis of medium wave signals.

The input data is taken from the IQ data files created using the recording option. Typically you use a recording bandwidth of 100kHz over 12 or more hours.

  1. From the View tab in the ribbon bar select IQ Data File Analysis.
  2. In the IQ Data File Analysis window press the IQ Data File button to select the IQ data source.
  3. Select the display bandwidth.
  4. Press Analyse to create a display. This will usually take a few minutes as typically many gigabytes of data must be read and analysed.

Options

 

File

Select the file to be analysed. If this is a file in a series then the rest of the series is automatically added to the list. SDR-RADIO.com and SpectraVue recordings are supported.

FFT

The FFT size determines the resolution bandwidth - a larger FFT size results in a finer resolution bandwidth and fewer (but higher resolution) display rows.

As you change the FFT value the Display Rows value shown at the bottom of the display changes.

Windowing

The windowing function is selected to reduce spectral leakage, the default option is usually sufficient.

Start, Finish

The data used to generate the display.

Display

In this example data is displayed centered on 650kHz (data recording in Atlanta, Georgia).

You see at least 20 carriers within a few Hertz of each other!