Development of a Low-Resource HF Radio Receiver for Sounding Rocket Applications

Ground-based transmissions combined with rocket-based receivers have long been used to produce absolute electron density measurements in the D-region of the ionosphere. While these techniques date back to the Friedrich and Seddon methods of the 1950s, recent advances in microcontrollers and software-defined radios (SDRs) provide a powerful alternative to analog systems. Recently, components for analog radio systems have become scarce and lack interfacing ability, while modern SDRs offer a better alternative to studying the ionosphere. Bulky traditional software-defined radios (i.e., Ettus, HackRF, RX888, etc.) require a power-hungry host computer (Raspberry Pi). We present a low-cost alternative method using the Teensy Convolutional SDR, which is composed of an analog downconversion board and a sampling audio card. We further present laboratory testing results of the Teensy Convolutional SDR’s basic signal reception and signal strength properties, power draw, and mechanical layout. This work is in pursuit of an upcoming RockSat-X student-sounding rocket mission, where we will test the SDR in the space environment using existing AM radio transmitters as the emitters of opportunity.