shrieker: (also ping-pedo) a single-shot directional EM pulse generator mounted in a capsule suitable for mass driver deployment.
It is a truism of tactics that active sensors, while much more effective than passive sensors, can rarely be used since they are even more effective at disclosing the user’s position to other vessels. The shrieker represents a compromise with this truism; given effective localization and a little mathematics, there is no necessity for the sensor emitter and the sensor receiver to be in the same location. Thus, it provides the means to implement this by emitting the radar/lidar pulse from a point distant from the launching vessel.
The shrieker is far from a perfect solution. It provides partial information on the location of its launcher, especially if the pre-pulse run is short, or the opposition’s sensors are sufficiently sensitive to pick up Doppler distortion in the emitted pulse; and deployments are limited inasmuch as, although directional, a shrieker can only be used in situations in which its pulse will not illuminate the launching vessel or other friendlies to the passive sensors of the opposition. Nonetheless, the additional information provided by even limited active sensor capability can make all the difference in a tactical situation.
– Blackjacket’s Dictionary
spotter (n.): An ancient spacer’s tool, dating back almost as far as the navigator’s sextant, the engineer’s multi, or the medtech’s hand effector, used for locating and profiling distant objects in space: a boon to anyone who has to manage a docking bay, shift cargo in microgravity, perform extravehicular activities in crowded neighborhoods, or engage in the smallest of small-craft operations, which is to say, riding a candle.
The original spotters were no more than handheld radar transceivers with direct audio feedback into the user’s helmet interface. Wave it around, and when you hear beeping, it’s pointing at something. The faster the beeping, the closer that something is to you. Learning what a particular rate meant in terms of range, and keeping an ear on the change of beep rate, were left as skills for the user to develop.
The modern spotter is a rather more sophisticated device, thanks to miniaturization and commercial development. HUD feedback now monitors its position relative to your body to provide a more accurate sense of direction, and even the most basic models provide precise range and closing rate information. More advanced models use a phased-array antenna to sweep the beam across a target once detected, providing a profile for target recognition purposes and an estimate of spin.
Of course, there is in theory very little use for a spotter in the current age of space, since all spacecraft from the largest to the smallest include a transponder, and are further constructed from LOP-compliant hardware which will obligingly disclose its location upon receiving a network request. The Grand Survey has detailed charts of every object in space larger than a child’s ball. All objects within range should therefore, says theory, already be highlighted on your HUD.
It is a sign of the tremendous respect that spacer culture has for theory that there are at least a brace of spotters stored in every airlock and docking bay from the Core to the Rim.
– A Star Traveler’s Dictionary