Re: FT Sensor Rules -- Request for Comments [LONG]

On 23-Oct-04, at 6:55 PM, Laserlight wrote:

> Tony said:
>> For two sensor suites detecting the same radiation signature, the
>> one with an active component will have the greater range, since it
>> is able to detect targets that do not emit with the detected
> signature,
>> and the reflections will add to any inherent emissions from the
>> target.
>
> I don't think you understood Doug's point.  Let's take the example of
> three battleships, Asad ed Din (actively searching) and Saif ed Din
> (passively searching) versus Fernando Poo (passively searching), and
> assume they're all equally reflective and have equal sensor suites.
>
> Asad is putting out an amount of energy which has to be sufficient to
> get to Fernando, reflect off Fernando, get back to Asad, and still be
> above detection threshold.  Because the distance from A-to-F-to-A is
> twice the distance from A-to-F, the inverse square law means the
> reflected signal strength A hears is one quarter the signal strength F
> hears (assuming F is a perfect mirror).  Therefore Fernando is going
> to detect Asad a long time before Asad detects Fernando.
>
> OTOH, Fernando and Saif will detect each other at the same time.
>

No, I understood Doug's point. The only reason that A is detected 
earlier
is because it's active component gives it away - this is already
covered by Jerry's rules. Now if all three ships are in passive mode,
then the range that they will detect each other will be much less
than if one or more are using active sensors.

> I thought passive sonar outranged active sonar.  Perhaps it is what 
> your sensor is detecting.
>  
> Gracias,
>
> Glenn "warbeads"

The important thing to understand is that the receiver component is
always passive - the active component only provides a signal to
reflect off the target. Sonar happens to be my area of expertise. Active
sonar has a much greater range, and is much more accurate at detecting
range and bearing to the target.

Cheers,
Tony C.