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| -rw-r--r-- | 08.-Passive-Radar.md | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/08.-Passive-Radar.md b/08.-Passive-Radar.md index ba240b1..7eb5cb0 100644 --- a/08.-Passive-Radar.md +++ b/08.-Passive-Radar.md @@ -10,7 +10,7 @@ In a basic two channel passive radar system, you have one ‘reference’ antenn The second ‘surveillance’ antenna points towards the targets of interest, such as aircraft, cars or marine vessels. The illuminating signal is reflected off the body of these targets, and the reflections are received by the surveillance antenna. -The reflections are then processed and correlated against the clean reference signal. The result is a ‘bistatic range-doppler’ display that shows detected targets as dots. The position of the dot on the display measures the velocity of the object, and the bistatic distance. +The reflections are then processed and correlated against the clean reference signal. The result is a ‘bistatic range-doppler’ display that shows detected targets as dots. The position of the dot on the display measures the bistatic velocity of the object, and the bistatic distance. ## Passive Radar Geometry In a passive radar system, the geometry of the receiver, transmitter and targets of interest are very important for optimizing performance. @@ -88,7 +88,7 @@ $\mathrm{Bistatic Range (meters)} = R_b = cell * \frac{c}{fs}$ Where $c$ is the speed of light, and $fs$ is the sample rate (aka bandwidth), and $cell$ is the x-axis cell. The sample rate by default is set to 2.4 MHz. If you have an illumination signal that is smaller, you should set your sample rate to the closest possible bandwidth that matches that illumination signal. -So for example if we see an object at cell 50 on the x-axis, and we have a sample rate of 2.4 MHz we can calculate $\mathrm{Bistatic Range (meters)} = R_b = 50 * \frac{299792458}{2400000} = 15614 \mathrm{m} = 15.6 \mathrm{km}$ +So for example if we see an object at cell 50 on the x-axis, and we have a sample rate of 2.4 MHz we can calculate $\mathrm{Bistatic Range (meters)} = R_b = 50 * \frac{299792458}{2400000} = 6245 \mathrm{m} = 6.245 \mathrm{km}$ For converting doppler cells to Hertz the formula is as follows: |