solbergb wrote:A telescope is a passive sensor. All it does is collect light. SNIP quibbles after this first main point.
A telescope is NOT a sensor at all! Let alone a passive one! A telescope is 100% separate from a sensor or emitter passive or active!
Yes! Telescopes collect EM spectrum. Do not call it "light". "light" is a very minute portion of the EM spectrum. Telescopes can also SEND out EM spectrum along a fixed vector. All a telescope requires is an emitter. Just like in collection mode all it requires is a Data collection sensor.
Ye Godz, how do you guys think satellites work? They are all telescopes that send/receive information via their multiple "telescopes." Both active/passive sensors in the same stinking "telescope" using the exact same mirrors/lenses simultaneously! No, not all comm satellites have done so historically, but any semi modern one does as this allows vastly increased bandwidth. Its how Radio antennas work as well. They are doing so due to $$$ allowing one satellite to cover a larger area for uplink/downlink angles. Otherwise you cut your bandwidth in half. You lose a small portion of S/N ratio by doing so though as more power is coursing through the emitters/data collectors in question creating heat, noise. Active cooling is required(heat pipes transferring into massive heat sinks on said satellites that are also there for half of said satellite being exposed to the sun and the other deep space)
NO, active sensors do NOT have higher resolution than passive. What they do have is a higher Signal to Noise ratio! More signal is coming BACK. Noise either remains the same or goes up slightly due to active emissions. Resolution remains the same. Resolution is determined by the lenses used along with the sensor! Optics 101. The data is there, but with a higher S/N ratio, you get useful information instead of "fuzz."
No, DW does not differentiate between passive/active distinct sensors. It would appear that DW already knows this, or someone in BuNine pointed out that they are the same bloody thing requiring telescopes on said sensor/emitter apparatus to focus their beams and to collect data. For instance in SoSag, Typhoon lost its Entire front Radar capability.
Night flashlights for goggles have been around forever. They have improved in 2 ways though. The difference has been that night vision goggles have narrowed their spectrum emissions(rely more on IR) along with dynamic processing for blinding effect and therefore allowing one to place filters over flashlights that better block the EM spectrum that the night vision goggles use.