An Optimal Design of PSN for SSB Signals Generation and Reception I

Summary:
One of the sixth order PSN (Phase Shift Network)'s has been optimized.

It has the following characteristics: the 6th order, 90 plus minus 0.750 degrees, and fh/fl = 44.177956.The fh/fl is a ratio of the highest to the lowest in frequency where phase differece of the psn is maintained within 90 plus minus 0.750 degrees. The undesired sideband suppression ratio is -43.7 dB at each of the frequencies with the maximum phase deviation of 0.750 degrees from 90 degrees between fh and fl.

The average suppression of the undesired sideband over the bandwidth of modulating frequencies between fh and fl is 6.4 dB better than the suppression at each of the above frequencies.

Table 1

Nr	Phase Deviation from 90 degrees	Normalized Frequency	Example 1. Frequency in Hz
1	-0.750	fl = 0.1504517	Fl = fl*F0 = 90.27
2	0.000	0.16465233	98.79
3	+0.750	0.20992848	126.0
4	0.000	0.29479009	176.9
5	-0.750	0.43511579	261.1
6	0.000	0.656871	394.1
7	+0.750	1.000000	F0 = 600.0
8	0.000	1.522369	913.4
9	-0.750	2.2982388	1379
10	0.000	3.3922442	2035
11	+0.750	4.7635269	2858
12	0.000	6.073403	3644
13	-0.750	fh = 6.64665	Fh = fh*F0 = 3988

Note: * is a multiplier operator, like 12.3*2.0 = 24.6.



Figure 1. Differential phase-shift characteristics of the network
The graph has a twofold symmetry, of which the axis is
on a normalized frequency of 1. So the left half of the graph
is the same as the right half with respect to the axis, as in a mirror.



Figure 1-2. Undesired Sideband Suppression Ratio Characteristic of the network
The graph is symmetric.


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Copyright (C) 2004 - 2007, 2010 - 2012 　Shigeo Yamase JA7UHV