Analyzing EMI-Induced Degradation of HF SDR Receiver Sensitivity and Its Effects

This paper examines the vital link between conducted electromagnetic interference (EMI) and the degradation of sensitivity in HF SDR receivers. Observing anomalies in sensitivity behavior prompted a thorough examination across five hardware iterations. Focused on the HF frequency range of 1.6 MHz to 30 MHz, encompassing the conducted EMI spectrum (20 kHz to 30 MHz), we unveil how crystal oscillator and power supply harmonics generate unwanted signals within this band. A comprehensive testing regime and strategically planned interventions successfully addressed sensitivity loss. This underscores the significance of precise power supply design in RF electronics, bearing profound implications for enhancing the performance of robust HF SDR receivers in the face of EMI challenges.