INDEX 



The subject indexes of all STR volumes are combined in a master index printed in a separate volume. 

 For access to the index volume consult the Army or Navy Agency listed on the reverse of the half-title page. 



Absolute humidity, definition, 132 

 Absorption by the atmosphere 



see Atmospheric alisorption and scat- 

 tering 

 Absorption coefficient of spherical rain- 

 drops, 157-158 

 Absorption cross section of raindrops, 



157-158 

 Adiabatic lapse rate, drv (definition), 



132-133 

 Air, modification by sea surface, 124 

 Air mass, definition, 132 

 Aircraft cross sections 

 eiTect of frequency, 203 

 effect of type and dimensions of air- 

 craft," 203 

 effect of "wind, 203 

 Anemometers, 99-100 

 Angle-of-arrival, 205-212 



comparison of measured and com- 

 puted angle, 211 

 deviation from true bearing, 210 

 direct and reflected wave, 206 

 effect of atmospheric stratification, 



208-210 

 effect of rain, 206 



effective coefficient of reflection, 206 

 horizontal, 206 

 meteorological analysis, 207 

 method of measurement, 205 

 theory from meteoi-ological point of 



view, 207 

 vertical, 206 



vertical variations in ray paths, 209 

 Angle-of-departure, 207 

 Antenna height, effect on signal 



strength, 37-39, 44-45 

 Antennas for S- and X-ljand trans- 

 mission, 33-34 

 Antigua radio wave transmission ex- 

 periments, 33-46 

 Arizona radio wave transmission ex- 

 periments, 29-32 

 Artificial echo, radar, 198 

 A-scope, radar, 192, 198 

 Atmosphere, standard (definition), 130 

 Atmospheric absorption and scattering, 

 148-186 

 attenuation by idealized precipita- 

 tion forms, 162-165 

 attenuation by rain, 149, 157-159 

 attenuation bv spherical drops, 157- 



159 

 attenuation due to water vapor, 185 

 back scattering, 167-171 

 British work, 180 

 by clouds, fogs, rain, 159-162, 180 

 bj' oxygen and vapor, 180 

 by spherical particles, 150-154, 157- 



159 

 dielectric constant of licjuid water, 

 180-185 



dielectric constant of steam, 185-186 



gaseous absorption, 148-151, 171 



K-band absorption by water vapor, 

 175-177 



K-band attenuation by rainfall, 177- 

 180 



scattering amplitudes, 154-157, 171 



scattering by spherical raindrops, 

 165-167 



scattering variations with frequency, 

 146 



technique for measuring attentuation 

 in the atmosphere, 175 

 Atmospheric refraction of radio waves 



see Refractive index and M curves 

 Atmospheric stratification and angle- 

 of-arrival, 208 

 Attenuation 



see Atmospheric absorption and scat- 

 tering 



Back scattering, 153-154, 167-171 

 Balloon sondes, captive, 101-104 

 cable and balloon techniques, 103-104 

 radio transmission tyj^e, 101-102 

 wired transmission tjqie, 102-103 

 Bell Telephone Laboratories (BTL), 

 angle-of-arrival measurements, 

 207 

 Bermuda high-pressure area, 40 

 Brillouin attenuation formulas for at- 

 mospheric absoiption, 154 

 British radio transmission experiments, 

 47-60 

 atmospheric absorption of micro- 

 waves, ISO 

 fading in line-of-siglit, 58-59 

 forecasting system based on tempera- 

 ture gradient, 59-60 

 objectives of study, 47 

 reflection experiments, 144 

 sea echoes, 197 



wave propagation over land, 52-58 

 wave propagation over the sea, 47-52, 

 54-56 

 Bulbs (meteorological instruments), 97- 

 98 



California Institute of Technology, ane- 

 mometer, 100 

 Centimeter wave propagation, over- 

 land, 52-58 

 see also Radio wave transmission 

 correlation between theory and ob- 

 servations, 54-56 

 diurnal signal variations, 53-54 

 effect of water vapor in atmosphere, 



53-54 

 field strengths, 56-58 

 seasonal signal variations, 53-54 

 Centimeter wave propagation, oversea, 

 47-52, 54-56 



see also Radio wave transmission 



effect of temperature, 56 



light beam behavior, 49 



meteorological factors, 50-52 



monitoring equipment, 56 



observations at variance with theory, 

 54-55 



optical vs nonoptical paths, 50-51 



research recommendations, 54-55 



S-band operation, 48-52 



Mtes for experimental stations, 48 



soundings as guide to signal varia- 

 tions, 54 



transmission paths, 48 



X-band operation, 48-52 

 Climate of the West Indies, 39-40 

 Clouds, attenuation of radio waves, 160 

 Clutter, radar, 201 



Desert temperature, diurnal variation, 



29-32 

 Dielectric constant 



fresh water pond, 141 



ground, grass covered, 143 



ground, sandy, 139, 143 



groimd, saturated, 141 



ice, 184 



liquid water, 180-185 



sea water, 141 



steam, 185-186 



tap water, 141 



water, temperature variations, 156, 

 183-184 



water vapor, 185 

 Dielectric constant, measurement 

 methods 



reflection-transmission methods, 180 



resonator Q method, 182 



standing wave ratio method, 181 

 Diin-nal variations in radio transmis- 

 sion, 29-32, 50, 53-54 

 Dry adiabatic lapse rate, definition, 



132-133 

 Dry sandy ground, reflection coeffici- 

 ents, 139 

 Ducts, 118-128 



see also Ocean ducts, radio trans- 

 mission in 



computed climatological informa- 

 tion, 126-128 



detennination of width, 123-125 



factors affecting extent of trapping, 

 123 



modification of air by sea surface, 124 



pressure, temperature, and humidity, 

 119-120 



refractive index, 120-123 

 Ducts in the trade wind regions, 38-43, 

 93-96 



definition, 94 



elevated ducts, 94-95 



frequenc}' of occurrence, 95 



223 



