Swarm-E (formerly known as e-POP)

In the spirit of making data from the Radio Receiver Instrument (RRI) onboard Swarm-E (formally known as e-POP) more accessible to the ham radio community, we have converted RRI's data into a ".raw" format so that it can be ingested into open source software such as Gqrx or GNU Radio.  We have done this for all RRI data related to the 2015, 2017, and 2018 ARRL Field Days.

We encourage everyone to help us identify hams in RRI's signal.  You can use the Gqrx tool discussed here, or you can use your own technique.  If you decode a ham's call sign, if you would like to share your technique, or if you have any comments or suggestion contact us and let us know! 

To help organize your findings, you can download a spreadhseet containing that you can fill out and send to us.  Feel free to create your own spreadsheet or modify this one.  

Swarm-E (e-POP) RRI

Swarm-E RRI is a digital radio receiver with 4 3-m monopole antennas.  In most cases, the monopoles are electronically configured into a crossed-diople configuration.  In this configuration, RRI records I/Q samples for the two dipoles.  RRI has a sampling rate of 62500.33933 Hz, and a ~40 kHz bandpass, and can be tuned to anywhere between 10 Hz and 18 MHz.  More information on Swarm-E RRI can be found in the Swarm-E RRI instrument paper or Gareth Perry's recent Radio Science article.

Data Format

Each data file contains raw 32 bit complex I/Q samples for a given RRI dipole at a given frequency.  The samples are interleaved, e.g., IQIQIQIQ... The data files do not contain any metadata.  Any information regarding the time, frequency, and corresponding RRI dipole is in the file name.  

Filename Format

The filename format gives information about the time and data of the recording, the tuned frequency, and which of RRI's dipoles the recording corresponds too.  For example, gqrx_20150628_011614_3525000_62500_RRI_Dipole1 contains data recorded on Dipole 1, starting at 01:16:14 UT on June 28, 2015, at 3525000 Hz (3.525 MHz), at a sampling rate of 62500 Hz (RRI's 62500.33933 Hz sampling rate).

Gqrx

We have opted to convert the data into the .raw format so that it can be ingested into Gqrx.  There are other ways of analyzing RRI's data; this is just one way which we felt was as easy first step.  We are open to posting about other techniques on the HamSCI site as well.  To help get started with Gqrx, we have developed a How to play an RRI raw IQ file on Gqrx page.

Data Files

The data files may be downloaded directly from the Zenodo repository here

 

By Nathaniel A. Frissell (W2NAF), Philip J. Erickson (W1PJE), Ethan S. Miller (K8GU), William Liles (NQ6Z), Kristina Collins (KD8OXT), David Kazdan (AD8Y), and Nathaniel Vishner (KB1QHX)

Photo by Laura Gooch (N8NFE)

The Ham Radio Science Citizen Investigation (HamSCI) is an international collective of professional researchers and amateur radio operators working together to simultaneously advance the fields of space science and amateur (ham) radio activities. The 2nd US HamSCI meeting was held March 22-23, 2019, organized by Nathaniel Frissell of the New Jersey Institute of Technology (NJIT) and hosted by the Case Amateur Radio Club (Case ARC) at Case Western Reserve University (CWRU) in Cleveland, OH. The theme of this year’s meeting was “Ionospheric Effects and Sensing,” which includes the use of amateur radio techniques for the characterization and observational study of ionospheric phenomena such as traveling ionospheric disturbances, sporadic E, response to solar flares, geomagnetic storms, and other space weather events.

HamSCI will again be at the Dayton Hamvention as part of the new Ham Radio 2.0: Innovation and Discovery area sponsored by the Yasme Foundation. Come visit the HamSCI Booth and Forum to learn about projects on the cutting edge of ham radio science and engineering research, including new directions in Sporadic E research, causes of F region ionospheric variability, how propagation works on the new 630 and 2200 m bands, the Personal Space Weather Station, and more. Hamvention will be held May 17-19, 2019 at the Greene County Fairgrounds in Xenia, Ohio.

The United States National Science Foundation (NSF) has recognized the need to join the amateur radio and professional science communities through a recent grant award to support the upcoming HamSCI Workshop from March 22-23, 2019 in Cleveland, OH. The conference is hosted by the Case Western Reserve University Amateur Radio Club and organized and administered by the New Jersey Institute of Technology (NJIT). The NSF conference grant from the Geosciences Directorate will provide important facilitation for conference activities and associated logistics.