Characteristic of electromagnetic radiation or acoustic wave propagation which means waves which travel in a direct path from the source to the receiver
انتشار دید مستقیم نوعی از انتشار امواج الکترومغناطیسی است (fa)
전자기파 또는 음파가 직선으로 전달되는 것 (ko)
characteristic of electromagnetic radiation or acoustic wave propagation which means waves which travel in a direct path from the source to the receiver (en)