Please use this identifier to cite or link to this item:
Title: The effect of solar activity on the Doppler and multipath spread of HF signals received over paths oriented along the mid-latitude trough
Authors: Warrington, E. Michael
Stocker, A.J.
First Published: 11-Feb-2011
Publisher: American Geophysical Union
Citation: Radio Science, 2011, 46, RS1014.
Abstract: Measurements of the Doppler and delay spread associated with HF signals propagating along an oblique (1440 km) path tangential to the midlatitude ionospheric trough are presented for sunspot maximum and minimum. During the day, Doppler spread is independent of solar activity, but for winter and equinoctial nights, it is very much higher at sunspot maximum. The delay spread is also generally higher at sunspot maximum for all seasons and times of day. For sunspot minimum, measurements from a second, longer path (1800 km) are also presented. The observed Doppler and delay spreads are similar for both paths. Finally, a novel method of more accurately deriving the delay spread defined by the International Telecommunication Union (i.e., the largest delay spread including all modes that have a peak power within a user-defined threshold of that of the strongest mode) from Voice of America coverage analysis program (VOACAP) predictions is presented. For the first time, the predicted values are compared with the measured delay spreads and, while there is generally good agreement at sunspot minimum, the agreement at sunspot maximum tends to be poor because the behavior of the high-order ionospheric modes (e.g., 3F2) is not well predicted by VOACAP.
DOI Link: 10.1029/2010RS004482
ISSN: 0048–6604
Version: Publisher version
Status: Peer-reviewed
Type: Article
Rights: © American Geophysical Union 2011. Deposited with reference to the publisher's archiving policy available on the SHERPA/RoMEO website.
Appears in Collections:Published Articles, Dept. of Engineering

Files in This Item:
File Description SizeFormat 
2010RS004482.pdf336.92 kBAdobe PDFView/Open

Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.