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--- communication:examples [2008/06/07 18:24] – rocketboy
+++ communication:examples [2008/07/19 23:33] (current) – external edit 127.0.0.1
@@ Line 17: / Line 17: @@
 Which at 2.4GHz equates to a distance of between 32 and 63Km depending on receiver
 ====== Practicality of using 2.4GHz FM TV from a balloon payload ======
-Licence exempt FM TV modules running in the 2.4GHz band are readily available in the UK for CCTV application – what's more more this band is explicitly allowed to used used in airborne TV applications.  So what sort of distances can be achieved?
+Licence exempt FM TV modules running in the 2.4GHz band are readily available in the UK for CCTV application – & what's more this band is explicitly allowed to used used in airborne TV applications.  So what sort of distances can be achieved?
 Assuming:
-A Transmitter power of about 10dBm (about 10mW) – all that is allowed.
+  * A Transmitter power of about 10dBm (about 10mW – all that is allowed).
-Payload antenna gain is 0dBi (omni-directional)
+  * Payload antenna gain is 0dBi (omni-directional)
-A Large ground station antenna of 24dBi (e.g. 3ft diameter dish)
+  * A Large ground station antenna of 24dBi (e.g. 3ft diameter dish)
-A receiver sensitivity of between -85dB (average) -91db (very good) for a (borderline) 10db video signal to noise ratio.
+  * A receiver sensitivity of between -85dB (average) -91db (very good) for a (borderline) 10db video signal to noise ratio.
 This gives a maximum path loss of between:
@@ Line 35: / Line 40: @@
 Which at 2.4GHz equates to a distance of between 9 and 18Km depending on receiver
+----
-The use of bigger antenna dishes would result in longer distances – as a general rule – doubling the dish diameter will double the workable distance.
+The use of bigger antenna dishes would result in longer distances – as a general rule doubling the dish diameter will double the workable distance.