sdrangel/plugins/samplesource/fcdpro

FunCube Dongle Pro input plugin

Introduction

This input sample source plugin gets its samples from a FunCube Dongle (FCD) Pro device.

Interface

The top and bottom bars of the device window are described here

1: Common stream parameters

1.1: Frequency

This is the center frequency of reception in kHz.

1.2: Start/Stop

Device start / stop button.

• Blue triangle icon: device is ready and can be started
• Green square icon: device is running and can be stopped
• Magenta (or pink) square icon: an error occurred. In the case the device was accidentally disconnected you may click on the icon, plug back in and start again.

1.4: Stream sample rate

Baseband I/Q sample rate in kS/s. This is the device sample rate (4) divided by the decimation factor (6).

2: Local Oscillator correction

This is the correction to be applied to the local oscillator in ppm.

3: Auto correction options

These buttons control the local DSP auto correction options:

• DC: auto remove DC component
• IQ: auto make I/Q balance. The DC correction must be enabled for this to be effective.

4: Decimated bandpass center frequency position relative to the FCD Pro center frequency

• Cen: the decimation operation takes place around the FCD Pro center frequency Fs
• Inf: the decimation operation takes place around Fs - Fc.
• Sup: the decimation operation takes place around Fs + Fc.

With SR as the sample rate before decimation Fc is calculated as:

• if decimation n is 4 or lower: Fc = SR/2^(log2(n)-1). The device center frequency is on the side of the baseband. You need a RF filter bandwidth at least twice the baseband.
• if decimation n is 8 or higher: Fc = SR/n. The device center frequency is half the baseband away from the side of the baseband. You need a RF filter bandwidth at least 3 times the baseband.

5: Decimation factor

The I/Q stream from the FCD Pro ADC is downsampled by a power of two before being sent to the passband. Possible values are increasing powers of two: 1 (no decimation), 2, 4, 8, 16.

6: Transverter mode open dialog

This button opens a dialog to set the transverter mode frequency translation options. The details about this dialog can be found here

7: Set default values

Use this push button to force default reasonable values for all parameters below (8)

8: Parameters

This panel lists all parameters that are the same as in the Windows utility interface showing the block diagram of the FCD:

• LNA Enh: equivalent of the "LNA enhance" parameter
• Band: equivalent of the "Band" parameter
• Bias: equivalent of the "Bias current" parameter
• Mode: equivalent of the "IF gain mode" parameter
• LNA G: equivalent of the "LNA gain" parameter
• RF filt: equivalent of the "RF filter" parameter
• Mix G: equivalent of the "Mixer gain" parameter
• Mix filter: equivalent of the "Mixer filter" parameter
• Gain1: equivalent of the "IF gain 1" parameter
• RC filt: equivalent of the "IF RC filter" parameter
• Gain2: equivalent of the "IF gain 2" parameter
• Gain3: equivalent of the "IF gain 3" parameter
• Gain4: equivalent of the "IF gain 4" parameter
• IF filt: equivalent of the "IF filter" parameter
• Gain5: equivalent of the "IF gain 5" parameter
• Gain6: equivalent of the "IF gain 6" parameter