Channel Rx plugins

Channel Rx plugins

These plugins live on the reception (Rx) side. Plugins can be used as a source of audio (media in general) or display (i.e. analyzer). They work on the data received in a "channel" that is a piece of spectrum carved into the spectrum received from the input plugin.

One nice thing about this approach is that any number of different channels can be accommodated within the reception spectrum. Of course your computer hardware will set the limit.

The plugins documented here are:

Channel analyzer plugin

This plugin has no audio output and is used to visualize and analyze signals. It has a spectrum and scope combined display the spectrum and the scope sharing the same trigger which helps in visualizing the spectrum of pulsed signals. The user interface is described here

Note that the old Channel Analyzer plugin was decommissioned in favor of the "New Generation" NG suffixed plugin that was renamed simply "Channel Analyzer"

ADS-B decoder plugin

This plugin is used to decode and visualize ADS-B messages. The user interface is described here

AM demod plugin

This plugin is used to listen to AM stations such as air traffic or AM broadcast. The user interface is described here

ATV demod plugin

This plugin can be used to watch amateur analog television (ATV). This is black and white and there is no sound carrier. Low refresh rates (FPS) and small number of lines are implemented to support NBTV (Narrow Band TV). The user interface is described here

Chirp Chat demod plugin

Chirp Chat is an experimental mode developed only in SDRangel based on chirp modulation analogous to LoRa. In fact it can also decode LoRa messages. This version can work at extremely low SNR. The user interface is described here

DATV demod plugin

This plugin can be used to watch digital amateur analog television (DATV). Accepted standards are DVB-S and DVB-S2. Please note that DVB-S2 does not perform very well and needs a high SNR (>20dB) to work properly. The user interface is described here

DSD (Digital Speech Decoder) demod plugin

This plugin is used to listen to digital voice transmissions. At present it covers the following digital speech formats:

• DMR/MOTOTRBO
• D-Star
• dPMR
• Yaesu System Fusion (YSF)
• NXDN

More information and user interface description can be found here

File sink plugin

This plugin can be used to record channel I/Q data. Its functionality replaces the former I/Q recording from each device user interface. The user interface is described here

FreeDV demodulator plugin

This plugin can be used to demodulate and decode FreeDV signals (see: https://freedv.org). Not all modes are supported. More information and user interface description can be found here

LoRa demod plugin

This plugin can be used to visualize and decode LoRa (Long Range) modulation designed by Semtech. It comes from the original source code and decoding technique has been preserved as is. It has been reported that it works in some cases but there is no formal support for it.

NFM demod plugin

This plugin is used to listen to a narrow band FM station such as PMR or Amateur Radio. The user interface is described here

SSB demod plugin

This plugin is used to listen to SSB (possibly DSB) or CW stations such as Amateur Radio. The user interface is described here

WFM demod plugin

It is just the wideband version of the NFM demod plugin. It has no de-emphasis nor possibility of stereo output. If you plan to listen to wideband broadcast FM you should rather use the Broadcast FM demod plugin. The user interface description and more details can be found here

Frequency tracker plugin

This plugin can be used to track the center frequency of a carrier. It will try to adjust its center frequency on the carrier center frequency. It is normally used in conjunction with a utility program that monitors the plugin center frequency via reverse API. This utility can then make use of this information to control other plugins or any other purpose. The user interface is described here

Local sink plugin

This plugin sends I/Q samples from the baseband to a Local Input plugin source in another device set. It is basically the same as the Remote Sink channel plugin but pipes the samples internally instead of sending them over the network. The user interface is described here

Remote sink plugin

This plugin sends I/Q samples to another SDRangel instance that uses a Remote input sample source plugin to receive the samples. The user interface is described here

File sink plugin

This plugin can be used to record channel I/Q data. Its functionality replaces the former I/Q recording from each device user interface. The user interface is described here

SigMF file sink plugin

This plugin can be used to record channel I/Q data using the SigMF file format. It is only available when compiled from source and with GCC. The user interface is described here

UDP sink plugin

This plugin can be used to send samples to a listening application over the network using UDP blocks. For example this can be used to make a connection to GNUradio using its UDP source block. Optionally the audio at 48kHz sample rate can be returned to this plugin to be incorporated in the audio mix. The user interface description and more details can be found here

For an example of usage with multimon-ng to decode APRS look at https://github.com/f4exb/sdrangel/issues/25

This is different from the Daemon sink which purpose is to send the full baseband with no further filtering nor decimating.

VOR receiver

This plugin can be used to demodulate VOR (VHF omnidirectional range) navaids (navigation aids). VORs are radio naviation aids in the VHF 108 - 117.975MHz band commonly used for aircraft navigation. The user interface description and more details can be found here

Undocumented (yet) plugins

Broadcast FM demod plugin

This plugin is used to listen to broadcast FM stations with possible stereo output and RDS decoding