@conference {557, title = {Early Results from the Ionospheric Sounding Mode Using Chirp Ionosondes of Opportunity for the HamSCI Personal Space Weather Station}, booktitle = {2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)}, year = {2021}, abstract = {

The objective of the Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS) project is to develop a distributed array of ground-based multi-instrument nodes capable of remote sensing the geospace system. This system is being designed with the intention of distribution to a large number of amateur radio and citizen science observers. This will create an unprecedented opportunity to probe the ionosphere at finer resolution in both time and space as all measurements will be collected into a central database for coordinated analysis. Individual nodes are being designed to service the needs of the professional space science researcher while being cost-accessible and of interest to amateur radio operators and citizen scientists. At the heart of the HamSCI PSWS will be a high performance 0.1{\textendash}60 MHz software defined radio (SDR) [1] with GNSS-based precision timestamping and frequency reference. This SDR is known as the TangerineSDR and is being developed by the Tucson Amateur Packet Radio (TAPR) amateur radio organization. The primary objective of PSWS system is to gather observations to understand the short term and small spatial scale ionospheric variabilities in the ionosphere-thermosphere system. These variabilities are important for understanding a variety of geophysical phenomena such as Traveling Ionospheric Disturbances (TIDs) [2], Ionospheric absorption events, geomagnetic storms and substorms. We present early results suggesting signature of Traveling Ionospheric Disturbances (TIDs) from an ionospheric sounding mode that we intend to implement on the PSWS system, currently implemented on an Ettus N200 Universal Software Radio Peripheral (USRP) using the open source GNU Chirpsounder data collection and analysis code.

}, doi = {10.23919/URSIGASS51995.2021.9560441}, author = {Joshi, Dev and Frissell, Nathaniel and Liles, William and Vierinen, Juha and Miller, Ethan S.} } @proceedings {578, title = {HF Doppler Observations of Traveling Ionospheric Disturbances in the WWV Signal Received with a Network of Low-Cost HamSCI Personal Space Weather Stations}, year = {2021}, month = {09/2021}, publisher = {ARRL-TAPR}, address = {Virtual}, url = {https://youtu.be/kVY3E3e--_I?t=3495}, author = {Romanek, Veronica I. and Frissell, Nathaniel A. and Joshi, Dev Raj and Liles, William and Trop, Claire and Collins, Kristina and Perry, Gareth W.} } @conference {580, title = {HF Doppler Observations of Traveling Ionospheric Disturbances in the WWV Signal Received with a Network of Low-Cost HamSCI Personal Space Weather Stations}, booktitle = {American Geophysical Union Fall Meeting}, year = {2021}, month = {12}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {New Orleans, LA}, abstract = {

Traveling Ionospheric Disturbances (TIDs) are quasi-periodic variations in ionospheric electron density that are often associated with atmospheric gravity waves. TIDs cause amplitude and frequency variations in high frequency (HF, 3-30 MHz) refracted radio waves. We present observations of TIDs made with a network of Ham Radio Science Citizen Investigation (HamSCI) Low-Cost Personal Space Weather Stations (PSWS) with nodes located in Pennsylvania, New Jersey, and Ohio. The TIDs were detected in the Doppler shifted carrier of the received signal from the WWV frequency and time standard station near Fort Collins, CO. Using a lagged cross correlation analysis, we demonstrate a method for determining TID wavelength, direction, and period using the collected WWV HF Doppler shifted data.

}, url = {https://agu.confex.com/agu/fm21/meetingapp.cgi/Paper/888443}, author = {Romanek, Veronica I. and Frissell, Nathaniel A. and Joshi, Dev Raj and Liles, William and Trop, Clair and Collins, Kristina and Perry, Gareth W.} } @proceedings {577, title = {Observations of Mid-latitude Irregularities Using the Oblique Ionosonde Sounding Mode for the HamSCI Personal Space Weather Station (Proceedings)}, year = {2021}, month = {09/2021}, publisher = {ARRL-TAPR}, address = {Virtual}, url = {https://youtu.be/kVY3E3e--_I?t=2542}, author = {Joshi, Dev Raj and Frissell, Nathaniel A. and Liles, William and Vierinen, Juha} } @conference {585, title = {Observations of Mid-latitude Irregularities Using the Oblique Ionosonde Sounding Mode for the HamSCI Personal Space Weather Station}, booktitle = {American Geophysical Union Fall Meeting}, year = {2021}, month = {12}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {New Orleans, LA}, abstract = {

The spread in the echoes of high-frequency (HF, 3-30 MHz) radio waves from the F-region of the ionosphere was one of the earliest indications of plasma density irregularities in the mid-latitude F region ionosphere. Although mid-latitude spread F has been widely studied, the plasma instability mechanisms that create these irregularities are still largely unknown. This phenomenon can cause radio wave scintillation effects that degrade the performance of human-made technologies such as satellite communications and Global Navigation Satellite Systems (GNSS). Understanding these irregularities so that they can be anticipated and mitigated are important aspects of space weather research. The occurrence climatology and variability can also be helpful in validating models of these irregularities. Here, we present signatures of mid-latitude irregularities observed in oblique ionograms received near Scranton, PA transmitted by the Relocatable Over-the-Horizon Radar (ROTHR) in Chesapeake, Virginia. These observations are collected with the GNU Chirpsounder2 software, an open source software package capable of creating ionograms from frequency modulated (FM) chirp ionosondes. This ionospheric sounding mode will be implemented in the currently under-development Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS), a ground-based multi-instrument system designed to remote-sense the ionosphere using signals of opportunity. Using the data from the oblique ionograms, we generate the Range Time Intensity (RTI) plots that show ionospheric dynamics through measured path length variations as a function of time. We also compare the RTI plots with Range-Time-Parameter (RTP) plots from the SuperDARN HF radar in Blackstone, Virginia which commonly observes direct backscatter from decameter-scale irregularities within the region of ionosphere traversed by the ROTHR signal.

}, url = {https://agu.confex.com/agu/fm21/meetingapp.cgi/Paper/875589}, author = {Joshi, Dev Raj and Frissell, Nathaniel A. and Sarwar, M. Shaaf and Sami, Simal and Ruohoniemi, J. Michael and Baker, Joseph B. H. and Coster, Anthea J. and Erickson, Philip J. and Liles, William and Vierinen, Juha and Groves, Keith} } @proceedings {556, title = {Simultaneous observations of mid-latitude Ionospheric Irregularities in HamSCI Personal Space Weather Station and SuperDARN radar}, year = {2021}, month = {05/2021}, publisher = {SANSA}, address = {Virtual}, url = {https://www.sansa.org.za/events-outreach/superdarn-workshop-2021/}, author = {Joshi, Dev Raj and Frissell, Nathaniel A. and Liles, William and Vierinen, Juha} } @conference {311, title = {VLF Sudden Ionospheric Disturbance Receiver (Demonstration)}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, author = {Liles, William} }