Estimating Rain‐Specific Attenuation at Extremely High Frequencies From Disdrometer Measurements at Various Climate Zones in the US

ABSTRACT The raindrop size distribution (DSD) plays an essential role in understanding rain attenuation effects at extremely high frequencies (EHFs). Over 1 year of DSD measurements was taken at different Köppen–Geiger climate classifications within the United States. Optical disdrometers from Thies Clima were used to measure both the size and velocity of rain droplets. Rain‐specific attenuation estimates at various frequencies and rain rates below 40 mm/h were obtained and compared across the multiple locations. Results show that the International Telecommunication Union (ITU) model (ITU‐R P.838) generally falls near the median of results across multiple locations; however, the wide variance across the locations demonstrates that no single DSD or rain attenuation model can universally characterize rain attenuation at EHFs. This study provides valuable insights for designers of millimeter‐wave communication systems, helping them predict rain attenuation across various climate zones in the US.