Odanan, on 22 August 2013 - 02:28 PM, said:
Nice mech!
MWO's ECM already makes impossible to lock a mech you have line of sight. I can't see how a vehicle of dozens of tons can be more stealthier than that.
Well, one would have to look at what each of the systems does.
Null Signature System (
Tactical Operations, pg. 336)
- "Created by the first Star League, the null-signature system is an elaborate series of passive and active electronic countermeasures and heat baffles that combine to mask a BattleMech’s heat and electromagnetic signature."
- "While the Null-Signature System is engaged, attacks against the unit at Medium range receive an additional +1 to-hit modifier, while attacks at Long and Extreme Range receive an additional +2 to-hit modifier. Beagle Active Probes and their Clan equivalents cannot locate a hidden unit with an active Null-Signature System, and heat-seeking weapons (such as Heat-Seeking Missiles) calculate their to-hit modifiers against the unit as though it is 8 points cooler than it actually is. Only a Bloodhound Active Probe can penetrate the Null-Signature System’s masking."
Chameleon Light Polarization Shield (
Tactical Operations, pg. 336)
- "Created by the first Star League, the so-called Chameleon light polarization shield uses a primitive mimetic system to help mask the ’Mech on which it is installed from visual observation at long and extreme range. While it does not render the unit truly invisible, the effect does blur its outline, making the ’Mech harder to identify or attack."
- "While the shield is active, the ’Mech is more difficult to attack at long distance. Medium-range attacks receive an additional +1 to-hit modifier, and Long- or Extreme-range attacks receive an additional +2 to-hit modifier. Unlike most other stealth systems, these modifiers apply even if the attacking unit is infantry."
Stealth Armor (
TechManual, pg. 206)
- "Based on an effort to recover the long-lost Star League-era null signature system, the Capellan Confederation’s stealth armor technology is actually a complex system of heat baffles and layers of radar- and EM-absorbent materials that - while about as bulky as ferro-fibrous armor - provides the same physical protection as standard armor. Limited exclusively to BattleMechs, this system requires the use of a Guardian ECM suite to function, but when activated, the ’Mech becomes virtually invisible to hostile sensors and EW devices."
- "When the stealth armor system is engaged, the ECM continues to function normally, but the ’Mech suffers effects as if in the radius of an enemy ECM suite." (Total Warfare, pg. 142)
- "While the system is engaged, attacks against a unit equipped with stealth armor receive additional to-hit modifiers of +1 at medium range and +2 at long range. In addition, a ’Mech with its stealth armor system engaged cannot be attacked as a secondary target." (Total Warfare, pg. 142)
Guardian ECM (
TechManual, pg. 213)
"This broad-spectrum jamming and electronic countermeasure system revolutionized electronic warfare (EW). In a day when most communications and targeting systems had grown accustomed to a battlefield flooded by conventional electronic noise and counter-noise, the Guardian was powerful and smart enough to scramble all hostile electronics within a spherical “bubble” roughly 180 meters across. The Guardian could even adapt to and scatter contemporary EW packages like the Beagle Active Probe, Narc Missile Beacon and Artemis IV - all while simultaneously keeping friendly channels and targeting enhancers clear."
Angel ECM (
Tactical Operations, pg. 279)
- "Derived from captured Clan technology, research on the Angel ECM Suite began shortly after the Battle of Luthien as part of an effort to counter the increasingly sophisticated electronic warfare systems of the modern battlefield. Essentially a boosted, broader-spectrum version of the Guardian ECM, the Angel was shelved numerous times due to cost overruns and ultimately saved only with aid from ComStar."
- "The Angel ECM Suite works like standard ECM, but can also block the Bloodhound Active Probe, Artemis V and C3 Booster Systems, and even negates the locking systems of Streak missiles. Streak missiles fired into or through a hostile Angel ECM bubble will not fire if the to-hit roll fails, but on a successful Streak launcher attack, the attacker must roll on the Cluster table as though the launcher were a standard (non-Streak) model."
- "Units equipped with Stealth Armor can use the Angel ECM in place of the Guardian ECM for the same effect, using the same rules."
- "If the amount of friendly ECCM in a hex is equal to or greater than the enemy ECM in that hex, ECM does not function in that hex. For this purpose, the Angel ECM suite counts as two ECM or ECCM suites, or the player can choose to run the Angel at 1 ECM and 1 ECCM." (TacOps, pg. 100)
- "An Angel ECM Suite can be tuned to be 1 ECM or 1 ECCM while it generates ghost targets." (TacOps, pg. 102)
Void Signature System (
Tactical Operations, pg. 279)
- "An evolution of the Chameleon Light Polarization Shield and the Null Signature System, the Word of Blake’s experimental Void Signature System ties into a unit’s sensors and uses a large-scale variation on mimetic armor technology to render a BattleMech virtually invisible."
- "While a Void-Signature System is active, the effect is similar to Mimetic battlesuit armor."
- "The to-hit penalties for attacks against a BattleMech using a Void-Signature System are based on the number of hexes the ’Mech moved during the Movement Phase. For 0 hexes moved, the to-hit modifier is +3; for 1 to 2 hexes, +2; and for 3 to 5 hexes, +1. If the ’Mech moved 6 hexes or more, no modifier applies. Reduce these modifiers by 1 (to a minimum of 0) if the attacking unit is conventional infantry."
- "Only a Bloodhound probe can penetrate the Void-Signature System’s masking effect. The Watchdog system, Beagle Active Probe and their Clan equivalents may not detect a hidden unit using a Void Signature System."
The Capellans' Stealth Armor is essentially "a poor man's Null Signature System", where NullSig itself is very similar to the
ADAPTIV system created by BAE Systems (linked in Morang's post).
The Chameleon Light Polarization Shield is likely based on
electrochromic technology;
Popular Science ran an article in May 1997 regarding similar technologies being applied to the Joint Strike Fighter project (now the F-35) as a stealth system (see
here and
here).
The Void Signature System is essentially a combined package of NullSig and CLPS, but (like Stealth Armor and unlike either NullSig or CLPS) requires an ECM suite (either Guardian or Angel) to be installed and operational in order to function.
The Guardian ECM Suite ("...typically used to shield allied units from such equipment by emitting a broad-band signal meant to confuse radar, infrared, ultraviolet, magscan and sonar sensors...") is a multi-spectrum electronic warfare system that likely includes
electronic radar jamming equipment, some degree of
laser jamming equipment, an
infrared countermeasures (IRCM) system (likely very similar to the planned
CIRCM system), a sonar jamming system (see
here and
here), and some system meant to confuse
magnetometers and
magnetic anomaly detectors.
The Angel ECM suite is really just a single box containing two sets of (souped-up) Guardian ECM innards.