An Optimum Design of PSN for SSB Signals Generation and Reception III


Shigeo Yamase, JA7UHV

Summary:
One of the sixteenth order PSN's has been optimized with a successive approximation method.

It has the following characteristics: the 16th order, 90 degrees plus or minus 0.010 degrees, and fh/fl = 650.784.The fh/fl is a frequency ratio of the highest to the lowest over which differential phase shift of the psn is maintained within 90 degrees plus or minus 0.010 degrees. The undesired sideband suppression ratio is -81.2 dB (-81.18 dB) at each of the frequencies having the maximum phase deviation of 0.010 degrees from the ideal 90 degrees between fh and fl.

The average suppression of the undesired sideband is -87.2 dB (-87.23 dB) over the bandwidth of modulating frequencies between fh and fl.


Table 1.

Nr Phase Deviation
from 90 degrees
Relative Frequency Example 1.
Frequency in Hz
1 -0.0100 degrees fl = 0.039199601 fl*Fo = 19.5998
2 0.0000 0.04038943592 20.1947
3 +0.0100 0.04403107740 22.0155
4 0.0000 0.05034562911 25.1728
5 -0.0100 0.05971634119 29.8582
6 0.0000 0.07271207082 36.3560
7 +0.0100 0.09012180955 45.0610
8 0.0000 0.1130022535 56.5011
9 -0.0100 0.1427422220 71.3711
10 0.0000 0.1811468277 90.5734
11 +0.0100 0.2305467345 115.273
12 0.0000 0.2939395439 146.977
13 -0.0100 0.3751713466 187.586
14 0.0000 0.4791677826 239.584
15 +0.0100 0.6122302397 306.165
16 0.0000 0.7824133735 391.207
17 -0.0100 1.000000000 F0 = 500.000
18 0.0000 1.278096763 639.048
19 +0.0100 1.633372439 816.686
20 0.0000 2.086951661 1043.48
21 -0.0100 2.665448758 1332.72
22 0.0000 3.402060120 1701.03
23 +0.0100 4.337515350 2168.76
24 0.0000 5.520383725 2760.19
25 -0.0100 7.005635655 3502.82
26 0.0000 8.849381040 4424.69
27 +0.0100 11.09609322 5548.05
28 0.0000 13.75287471 6876.44
29 -0.0100 16.74583506 8372.92
30 0.0000 19.86269747 9931.35
31 +0.0100 22.71123168 11355.6
32 0.0000 24.75894939 12379.5
33 -0.0100 fh = 25.510464 fh*F0 = 12755.2

Figure 1. Differential Phase-Shift Characteristics of the optimized network.The graph is symmetric.So the left half of the graph is perfectly the same as the right half with respect to the axis, as your right hand is the same as your left hand in a mirror.

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Copyright (C) 2004 - 2005, 2010 Shigeo Yamase JA7UHV

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