VOLTAGE STANDING WAVE  RATIO  RELATIONSHIPS
VSWR REFLECTION RETURN POWER PERCENT
  COEFFICIENT LOSS (dB)  RATIO REFLECTED
1.01 .0050 46.1 dB  .00002 .002%
1.02 .0099 40.1 dB  .00010 .010%
1.04 .0196 34.2 dB  .00038 .038%
1.06 .0291 30.7 dB  .00085 .085%
1.08 .0385 28.3 dB  .00148 .148%
1.10 .0476 26.4 dB  .00227 .227%
1.20 .0909 20.8 dB  .00826 .826%
1.30 .1304 17.7 dB  .01701 1.7%
1.40 .1667 15.6 dB  .02778 2.8%
1.50 .2000 14.0 dB  .04000 4.0%
1.60 .2308 12.7 dB  .05325 5.3%
1.70 .2593 11.7 dB  .06722 6.7%
1.80 .2857 10.9 d B  .08163 8.2%
1.90 .3103 10.2 dB  .09631 9.6%
2.00 .3333 9.5 dB  .11111 11.1%
2.20 .3750 8.5 dB  .14063 14.1%
2.40 .4118 7.7 dB  .16955 17.0%
2.60 .4444 7.0 dB  .19753 19.8%
2.80 .4737 6.5 dB  .22438 22.4%
3.00 .5000 6.0 dB  .25000 25.0%
3.50 .5556 5.1 d B  .30864 30.9%
4.00 .6000 4.4 dB  .36000 36.0%
4.50 .6364 3.9 dB  .40496 40.5%
5.00 .6667 3.5 dB  .44444 44.4%
6.00 .7143 2.9 dB  .51020 51.0%
7.00 .7500 2.5 dB  .56250 56.3%
8.00 .7778 2.2 dB  .60494 60.5%
9.00 .8000 1.9 dB  .64000 64.0%
10.00 .8182 1.7 dB  .66942 66.9%
15.00 .8750 1.2 dB  .76563 76.6%
20.00 .9048 .9 dB  .81859 81.9%
30.00 .9355 .6 dB  .87513 87.5%
40.00 .9512 .4 dB  .90482 90.5%
50.00 .9608 .3 dB .92311 92.3%

 

Conversion of Return Loss to VSWR

dB
VSWR
  
dB
VSWR
  
dB
VSWR 
50.00 1.006   18.00 1.288   11.00 1.785 
46.06 1.01   17.69 1.30   10.88 1.80 
45.00 1.011   17.00 1.329   10.51 1.85 
40.09 1.02   16.54 1.35   10.50 1.851 
40.00 1.02   16.00 1.377   10.16 1.90 
36.61 1.03   15.56 1.40   10.00 1.925 
35.00 1.036   15.00 1.433   9.84 1.95 
34.15 1.04   14.72 1.45   9.54 2.00 
32.26 1.05   14.50 1.464   9.50 2.007 
30.71 1.06   14.00 1.499   9.00 2.10 
30.00 1.065   13.98 1.50   8.50 2.204 
29.40 1.07   13.50 1.536   8.00 2.323 
28.31 1.08   13.32 1.55   7.50 2.458 
27.32 1.09   13.00 1.577   7.36 2.50 
26.44 1.10   12.74 1.60   7.00 2.615 
25.00 1.119   12.50 1.622   6.50 2.796 
23.13 1.15   12.21 1.65   6.02 3.00 
20.83 1.20   12.00 1.671   6.00 3.01 
20.00 1.222   11.73 1.70   5.50 3.263 
19.08 1.25   11.50 1.725   5.11 3.497 
19.00 1.253   11.29 1.749   5.00 3.570 

dB volt / s-units

dBm
(R = 50 Ohm)
Voltage
S-units 
(S9=100 uV, R=50 Ohm)
S-units
(S9=50uV, 
R=50 Ohm)
- 7 dBm
99.88 mV
S9+60
  
-13 dBm
50.06 mV 
  
S9+60
- 17 dBm
31.58 mV
S9+50
  
-23 dBm 
15.83 mV 
  
S9+50
- 27 dBm
9.99 mV
S9+40
  
- 33 dBm
5.01 mV
  
S9+40
- 37 dBm
3.16 mV
S9+30
  
-43 dBm
1.58 mV
  
S9+30
- 47 dBm
1.00 mV
S9+20
  
-53 dBm
500.59 uV
  
S9+20
- 57 dBm
315.85 uV
S9+10
  
-63 dBm
158.30 uV
  
S9+10
-67 dBm
100 uV
S9
  
-73 dBm
50.00 uV
S8
S9
- 79 dBm
25.01 uV
S7
S8
- 85 dBm
12.58 uV
S6
S7
- 91 dBm
6.30 uV
S5
S6
- 97 dBm
3.16 uV
S4
S5
- 103 dBm
1.58 uV
S3
S4
- 109 dBm
0.79 uV
S2
S3
- 115 dBm
0.40 uV
S1
S2
- 121 dBm
0.20 uV
S0
S1
- 127 dBm
0.10 uV
  
S0