Title :
A study of tropospheric scintillations using SODAR
Author :
Narayana Rao, D. ; Reddy, K. Krishna ; Ravi, K.S. ; Rao, D.Narayana ; Murthy, M.J.Kesava ; Dutta, H.N. ; Sarkar, S.K. ; Reddy, B.M.
Author_Institution :
Dept. of Phys., Sri Venkateswara Univ., Tirupati-5, India
Abstract :
Tropospheric scintillations at 7.6 GHz over the Tiruttani-Tirupati line of sight microwave link have been analysed for the period of February 1987 to March 1988. The scintillation index (%) is observed to be predominantly a night-time phenomenon. Its occurrence is minimum during monsoon and postmonsoon seasons compared to premonsoon and winter seasons. The scintillation index has been observed to be positively associated with the initial radio refractivity gradient. The diurnal variation of structure intensity parameter Cn/sup 2/ computed from the scintillation data shows the value of Cn/sup 2/ to be minimum around midday and maximum at night. An attempt has been made to correlate tropospheric scintillations with SODAR structures. The studies show that the daytime convective conditions do not affect the microwave signal, whereas ground based inversions, elevated layers, rising inversions and wave motions are responsible for scintillations.<>
Keywords :
atmospheric acoustics; atmospheric structure; atmospheric temperature; atmospheric turbulence; microwave links; radiowave propagation; scintillation; sonar; tropospheric electromagnetic wave propagation; 7.6 GHz; AD 1987 02 to 1988 03; India; SHF; SODAR; acoustic sounder; daytime convective conditions; diurnal variation; elevated layers; ground based inversions; initial radio refractivity gradient; line of sight microwave link; night-time phenomenon; rising inversions; scintillation index; structure intensity parameter; tropospheric scintillations; wave motions; Radio propagation; Sonar;
Journal_Title :
Microwaves, Antennas and Propagation, IEE Proceedings H
