Cloaking devices, a type of ‘stealth’ technology, emit an energy field which bends light and other energy phenomena around a cloaked ship, rendering it invisible to both the naked eye and most sensors. However, while they’re powerful weapons, cloaks are not without their drawbacks. They require enormous amounts of power—so much that a ship cannot use many other systems, including shields, transporters, active sensors, and weapon systems, while the cloak is on. The ship can, however, use its communication devices or passive sensor systems, and doing so will not reveal its location to other ships. Cloaking devices work in atmospheres. But may be effectively useless due to the presence of atmospheric particulates and the like.
Starfleet dislikes cloaks, which it considers contrary to its mission as an exploratory organization, and does not use them. In fact, under the terms of the Treaty of Algeron, Federation ships are forbidden to use them. However, exceptions are occasionally made (most notably the USS Defiant, and the USS Ascendant).
Creative inventors have developed many other forms of technology to hide starships from those who would detect them. Examples include the energy sheath and the systems described below.
While the Federation cannot use true cloaks, it can equip ships with holo-emitters in the hull, which can surround the entire hull with a holographic projection, or projections into space around the vessel to fool enemy vessels. There are several different classes and types of Hull Emitters. A class Alpha emitter grid can make a ship appear to be any other ship of equal or lesser size. A class Beta emitter grid system can make a ship appear to be any other ship of equal or greater size, empty space, a floating asteroid, or the like.
A new technology dubbed a Para-dynamic holo projection net is a revolutionary advance in both Holo-graphic and Sensor Decoy technology. It's primary use is to deflect it's own unique warp signature up to 200 million kilometers from it's true location, throwing off pursuing craft. It can also be utilized to portray impressions of 'known' species vessels, such as Romulan, Klingon, Cardassian, Borg for obvious purposes. In close quartered Combat the PDHP net simulates actual Starships in space, portraying fake warp signatures, life signs, power spikes and drops to fool enemy sensors. It also projects sensor data such as impact damage and ship or vehicle destruction to near perfect simulation. Although the most sophisticated Sensor systems and the most experienced of Sensor officers can distinguish inconstancies in the projections, in fast paced fleet engagements a few distracting seconds is all a skilled commander needs to take charge of the field. Like the Prometheus-class of vessels, the entire ship is equipped with internal holo-emitters on every deck for a variety of reasons. This system also distorts the warp signature of the Frontier-class of vessel, nearby vessels, or other vessels so equipped, making the ship look like a random subspace energy phenomenon to long-range sensors.
Any of the types of hull holo-emitter systems are designed to fool not only to visual senses, but to standard sensors as well—a ship disguised like an asteroid registers as an asteroid on another ships sensors. However, a disguised ship cannot use weapons, shields, transporters, a cloaking device, communications systems, active sensors, or warp or impulse engines without instantly dispelling the illusion. The only exception is in the para-dynamic emitters, that allow use of weapons, communications, warp and impulse engines while the illusion is engaged.
(Para-Dynamic Grids cost 3x the ships size in SU’s)
Interferometric dispersion is a technique, which renders a ship undetectable by radar systems and other primitive sensors (but not modern 24th century sensors).
An Interphase generator is an advanced version of a molecular phase inverter, originally used by the Romulans, Klingons, and even the Federation to develop a ‘Phasing Cloaking Device’. The Federation succeeded in constructing a semi-working design, and later, the Romulans, but the Federation took the Interphase technology in a different non-cloak direction, including weaponry based on the technologies. When activated, an Interphase generator allows the vessel to pass through matter. The tactical and strategically advantages of such a system are obvious, whether it be a cloak or just the generator. The system is also required for Transphasic flight, in addition to other required systems for that FTW technology.
Masking circuitry is a type of device, which renders a ship difficult to detect with sensors or the naked eye. The Federation variation of this device allows the ship using it to scramble the targeting sensors of another vessel, forcing them to target their ship manually or ‘by eye’, greater increasing the difficulty to hit their vessel. This system is commonly used by Starfleet advanced fighters, but can be cancelled for one round by striking the ship using the device with a polaron burst.