Power line noise effects and new radio noise models

The EMC (Electromagnetic Compatibility) Technical Center (ECTC) conducted a three-year radio noise measurement study at 30 HF communication sites operated by the US Navy, US Army, and US Air Force. Two new models that describe the median noise observed at these sites are presented. The models closely describe the characteristics of noise at sites with noisy power lines and at sites with quiet power lines. Compared to the CCIR 258 noise models, the new models more accurately predict the impact of power line noise at HF communication sites. The models for sites with noisy power lines and and quiet power lines have been validated from 500 kHz to 30 MHz. The new models can also be used to show the overall benefit of mitigating power line noise around HF communication sites