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diff --git a/08.-Passive-Radar.md b/08.-Passive-Radar.md
index 492f195..e68255c 100644
--- a/08.-Passive-Radar.md
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@@ -108,7 +108,9 @@ So if we were using 560 MHz as our illuminator:
 
 $Bistatic Speed (m/s) = c / f * -f_b = 299792458 / 560000000 * -143 = 76.5m/s = 275 km/h$
 
-It is noted what with increased CPI you receive the benefit of great bistatic doppler resolution, however range resolution is not increased. Increase CPI does still have the advantages of more processing gain, resulting in weaker reflections being detected.
+Note that objects moving along the line connecting the transmitter and receiver will always have 0 Hz Doppler shift, as will objects moving around an ellipse of constant bistatic range.
+
+It is also noted what with increased CPI you receive the benefit of greater bistatic doppler resolution, however range resolution is not increased. Increase CPI does still have the advantages of more processing gain, resulting in weaker reflections being detected.
 
 # Bistatic Range
 The graph provided is a bi-static range doppler graph. Bi-static means that the measurement consists of a transmitter and receiver separated by some distance. This can get complicated, as instead of getting a simple range distance value from the receiver, we end up with an ‘constant range ellipse’ of possible range solutions that depend on some calculations based on the transmitter and receiver positions.