Saturday, December 18, 2010

A 5-Year 10-Meter Es Propagation Study Using PropNET - Part 6

Es Directional Characteristics:
One of the characteristics of Es to observe was to compare PropNET captures between different directional groups. Due to the varying volumes from each directional group, the following capture data is displayed as an “hourly percentage of the total day” for each group, and not the actual volumes. This allows us to compare groups to each other on an equal scale. Each hour charted was also based on a 3-Hour average method. For the most part, each directional group displayed similar trends. Peaks and valleys were usually no more than two hours off between directional groups. Only the Southern/Southwestern group was different and peaked during the other group’s lulls.

Specific Directional Groups:
After five years of this study, there existed sufficient information to display the specific peaks of activity towards 45-degree directional segments. Although it made statistical sense, it tended to cloud up the trends it was indicating.
The actual number of captures by 45-degree segments was as follows:
Direction Captures
South & S. West-151
As indicated, the numbers strongly point to an Easterly influence due to the number of participants over the years. To best display similarities and contrasts, comparing directional groupings seemed to be a better approach to show trends.
New Methods to Compare Directional Data:
After reviewing each directional group, distinctive patterns were apparent between them. Each group is separated into the following halves:
1. North and South
2. East and West
3. Northwest and Southeast
4. Northeast and Southwest.

Comparing North to South:
The following charts shows that as the sun rises, the opportunity to work stations towards the North (270° - 89°) is greater than Southerly (90° - 269°) ones. Both directional groups show the steadily improvement after sunrise. Both groups peak the hour prior to noon. Northerly opportunities decline after noon at a pace much greater than Southerly ones during this time.

A second peak of activity begins for both groups during the local 5 PM (17:00-17:59) hour. This helps confirms a dual-peaked diurnal pattern for both opposite directional groups. Once the sun sets, opportunities decline more rapidly for the Southerly group. The sun is located north of west at and after sunset from my QTH.

Therefore, Northern paths are best as the sun rises and as it sets. Southerly propagation is strongest during the afternoon hours when the sun is at a high elevation. The sun’s influence is quite notable.

Comparing East to West:
Separating the total data into these directional groups (East and West) show one obvious trend, follow the sun. Eastern capture opportunities are better than the Western ones after sunrise and peak during the local 10 AM hour. Activity declines steadily and peaks again during the 5 PM hour (the dual-peaked diurnal). Western capture opportunities improve at a slower rate after sunrise and peaked at the 1 PM hour (3 hours later). The Western activity decline after sunset is less than the Eastern counterpart, but opportunities after midnight become best to the east.

Comparing Northwest to Southeast:
Separating activity into Northwest and Southeast halves show that the sun’s location determines the best paths by time of day somewhat equally. Both show the dual peak diurnal. Of all the directional half groups, these two directions tend to stay closer in the hourly trends. The hours from sunrise to mid-afternoon show the only differences.

Comparing Northeast to Southwest:
Finally, the “follow the sun” scenario is more apparent for Northeast and Southwest divisions. Peaks in activity are clearly two hours different. Northeast occurs at 10 AM and Southwest at the Noon hour. For both directions, the late afternoon peaks are almost equal with a slight favoring towards the Southwest.

Performing a regression analysis on the data shows that during the course of the day the only differences seem to be from North to South. Southerly tracks seem to peak early in the daytime and decline quicker. These trends are minor for the most part. As shown the Es day begins when the sun comes up and ends during twilight hours.

Next: Probability Analysis

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