Targeting is always difficult, especially when a target is actively trying to impair an attackers targeting system. Called Electronic Warfare, the ability to impair an attacker's targeting computer, while simultaneously countering the attackers's ability to impair your targeting computer, is very important in modern combat, and this is true on land, sea, air, and in space. This article attempts to detail how electronic warfare works in a generalized fasion. The three fundamental aspects of electronic warfare are Electronic Counter Measures (ECM), Electronic Counter-Counter Measures (ECCM), and Electronic Warfare Systems (EWS). It is important to note that not everything generates ECM or ECCM or carries an EWS; most things do not have the space needed for proper electronic warfare equipment. The largest users of electronic warfare are space ships, ocean ships, military installations, and very large robots and fighters.
Electronic Warfare functions in two ways: to lessen an attacker's chance to strike a target and to negate a defender's ability to impair an attackers chance to hit. These basic functions are handled through Electronic Counter Measures (ECM) and Electronic Counter-Counter Measures (ECCM), respectively. Most military electronic warfare systems can perform both functions simultaneously, while civilian systems can only handle one function at a time. ECM impairs an enemy’s targeting systems and can prevent missiles, and similar tracking devices, from achieving a lock-on on the ship. ECCM's only purpose is to counter a target's ECM, it does not give an attacker any bonus to strike a target.
The amount of ECM and ECCM that a ship can generate is based mainly on its origin, its size, and its functions. Anything smaller then the largest fighters and robots will not be equipped with an electronic warfare system, and will not generate ECM or ECCM, but it will be affected by a target's ECM. The largest and most advanced military fighters and robots will generate a only around 1 point of ECM and 1 point of ECCM, but it will not be equipped with an Electronic Warfare System. ECM and ECCM generated by space ships is listed in Ship Classes and Types. Please remember that these numbers are for average units, more or less ECM and ECCM could be generated by a specially built unit or a unit with significantly advanced technology.
Missiles also generate ECM and ECCM, which allows them to avoid behind targeted by weapons and allows them to lock on a target that is generating ECM. While it may be strange to see something as small as a missile generating ECM, while a suit of power armor can't, it is simply because of how a missile is shaped, designed, and used, not its size. The amount of ECM generated by a missile or a bomb depends on its size, please see Modern Missile Design for more details. The amount of ECCM generated by a missile depends upon the guidance systems in that missile and which of those guidance systems can be used on the target See the Modern Missile Design's section on guidance systems for more details.
Each point of ECM generates a -1 penalty to strike a target with a direct fire weapon and to achieve a lock-on with a tracking weapon, such as a missile. Each point of ECCM negates a single point of ECM, but there is no affect or bonus if an attacker has more ECCM then a target has ECM. For example, a cruiser with 3 points of ECM and 2 points of ECCM and a battleship with 5 points of ECM and 5 points of ECCM are engaged in combat, any direct fire attack from the cruiser to the battleship would suffer a penalty of -3 to strike from electronic warfare (5 points of ECM -2 points of ECCM = 3 point penalty), but any direct fire attack from the battleship to the cruiser would suffer no penalty from electronic warfare (3 points of ECM -5 points of ECCM = 0 point penalty). A long range missile, with Passive Gravity Homing, Neutrino Homing, and Anti-Radiation guidance systems, launched by the cruiser at the battleship would have a penalty of -2 to strike from electronic warfare (5 points of ECM -3 points of ECCM generated by the guidance systems = 2 point penalty), but this does not include the bonuses to strike that those guidance systems provide. While this system seems unfairly prejudiced against larger vessels, the simple fact is that big ships have more internal space to hold powerful electronic warfare systems. Please note that any penalty or bonus to strike a target due to its size, such as a large vessel striking a smaller target, still apply as normal.
The generation of ECM and ECCM is only one part of Electronic Warfare, but hardly the only part. Another important facet of Electronic Warfare is the Electronic Warfare Systems. These systems are fairly large and usually only placed on large units, such as large space ships, ocean ships, and military installations. The presence of these systems gives a unit more options in combat then simply firing upon a target. The possibility of breaking a missile's lock-on on a target, without wasting weapons destroying the missile, frees up point defense turrets to be used against other annoyances, such as power armor, fighters, and robots.
Not all Electronic Warfare Systems are created equal, and only the largest and most sophisticated systems will have all or even most of the special functions listed below. The most rare abilities are Generate ECM and ECCM and Light Target, but the rest are fairly common. The number of special functions that an EWS can perform each melee varies widely, depending upon the number of combat actions that the unit has, although certain types of units gain extra combat actions that can only be used for the EWS. Please see Revised Combat for Large Vehicles, for more details on combat actions and what they can be used for besides Electronic Warfare Systems. Fighters, robots, and installations that are equipped with an EWS but do not possess combat actions instead can perform a number of special functions per melee from their EWS. For fighters and robots, using a special function requires a melee attack, while an installation is assumed to be able to perform that many special functions each melee under normal conditions. Each use of an EWS by these means is considered to be a single combat action as listed under the rules below.
Each of the following abilities require the use of one combat action per melee, and while some will last for the entire melee and can only be used once per melee, others can be used multiple times per melee.
A feature of some EWSs is to confuse tracking devices into thinking that the ship with the EWS is its target instead of the original target. This is done through a variety of artificial sensor signals and altering the original target’s electronic signature. Attracting tracking devices is useful for making the missiles go past their maximum range, to protect a vulnerable object, or to pull missiles towards an object better able to deal with tracking devices.
This ability targets a single tracking device or an entire volley and forces the devices to try to lock onto the new target. If they succeed, then the tracking devices will go after the new target, but if they fail then the tracking devices will not change from their original course. This ability cannot be used to confuse non-autonomous guidance systems, but it can be used to confuse autonomous guidance systems on a device that has both types of systems. If this occurs, then the tracking device loses the support of the autonomous guidance systems and any ECCM and bonus to strike that the guidance system generated. If this causes the missiles final strike roll to drop below the level needed to hit the target, then the tracking device will miss.
This ability can be used any number of times per melee and each use requires one combat action. All tracking devices to be affected by this ability must be no more than 20 miles (32.2 km) away in an atmosphere or 20,000 miles (32,187 km) away in space, but the original target of the tracking devices does not need to be within range. If used on a tracking device with no autonomous guidance systems, then their is no effect and the action is wasted.
This function is similar to the Attract Tracking Device function, but instead of changing the target of a tracking device, it completely erases the targeting ability of a tracking device. This ability targets a single tracking device, such as a missile, or an entire volley, and forces the affected devices to roll to strike the target again, but with an additional penalty of -2 to strike. The target does not get an additional chance to dodge or affect the tracking devices in any way.
This ability can be used any number of times per melee and each use requires one combat action. All tracking devices to be affected by this ability must be no more than 10 miles (16.1 km) away in an atmosphere or 10,000 miles (16,093 km) away in space, but the target of the tracking devices does not need to be within range. This ability only works on tracking devices with only non-autonomous guidance systems.
Certainly one of the most important parts of any EWS is its ability to generate both ECM and ECCM in addition to what the ship is already able to generate. This ability allows the source to not only generate additional ECM and/or ECCM, but it allows the generated points to be projected onto nearby units or onto the generating unit. The amount of ECM and ECCM generated by this ability varies widely depending on the size of the system, but the generated points can be distributed to any number of target within a radius of 10 miles (16.1 km) in an atmosphere or 30,000 miles (48,280 km) in space, as long as each target receives at least one point or either ECM or ECCM. For example, a large EWS may be able to generate ten points, which can be used as either ECM or ECCM, which it could then distribute to up to ten different targets, perhaps given three targets two additional points of ECM and a forth target four points of ECCM.
Alternatively, the system can be used to carpet an entire area with either ECM or ECCM that affects all targets within that area. When used in this manner, the system generates only a quarter of its normal ECM or ECCM, rounding all fractions down, but it affects all targets in a sphere with a radius of 1000 miles (1600 km) which can be centered on any point up to 5 miles (8 km) in an atmosphere or 10,000 miles (16,093 km) away in space. Using the system in this manner can only be used with ECM or ECCM, but not both.
Using the first method of this ability requires using one combat action and the EWS can distribute any or all of its points in a single use. Shared points last for an entire melee, but to change the number of shared points requires the use of another combat action. Using the second method of this ability requires one combat action and lasts for an entire melee, but neither method of this ability can be used again until the duration elapses or it is canceled and all points shared are immediately lost when the second method is used.
This is a simple function that is easily accomplished by a complex EWS. This ability merely uses a EWS to create a large sensor image of a target, which allows weapons to lock onto the target more easily. Anything targeting the affected object gains a bonus of +3 ECCM as long as this ability is functioning; this includes both direct fire weapons and tracking devices. This ability can only affect a single target with one use of a special function per melee, but the bonus lasts for one full melee.
This ability can be used any number of times per melee and against a single target, but the target must be no more than 20 miles (32.2 km) away in an atmosphere or 50,000 miles (80,467 km) away in space.
This ability allows a EWS to impair communications between objects that fall within the area of affect. Unfortunately, this ability will impair the communications of both enemy and friendly targets. All communication ranges are 10% of their normal range and all messages will be garbled and difficult to understand. For example, a ship with a standard radio communication system originally had a communication range of 60 miles (96.6 km) in an atmosphere or 60,000 miles (96,561 km) in space, but when affected by this ability, the ship will only have a communication range of 6 miles (9.7 km) in an atmosphere or 6000 miles (9656 km) in space. There is also a 75% chance that any given communication will be completely undecipherable by the receiving object. A ship equipped with sophisticated communication equipment or a powerful computer reduces this to a 50% chance.
There is a cumulative 5% per melee chance that an affected object will notice that its communications are being scrambled, but they will be unable to locate the source of the disruption. Each use of this ability requires one combat action and lasts for the entire melee. It affects all communication systems within a radius of 200 mile (321.7 km) in an atmosphere or 500,000 mile (804,672 km) in space.
This ability is extremely useful during the initial stages of combat and can allow many things to be hidden from enemy sensors until they are revealed. The ability disrupts and distorts all sensor systems within the area of effect, which also includes sensor systems on friendly ships. All sensor ranges are decreased to a quarter of their original values, minimum restrictions, such as weight, are doubled, and any chance of failure is doubled. For example, if a sensor originally had an 80% chance of detecting targets (20% chance of failure) over 60 tons (54.4 metric tons) within a range of 100,000 miles (161,000 km), then it would be reduced to having only a 60% chance of detecting targets (40% chance of failure) over 120 tons (108.9 metric tons) within a range of 25,000 miles (40,234 km).
There is a cumulative 5% per melee chance that an affected object will notice that its sensors are being scrambled, but they will be unable to locate the source of the disruption. Each use of this ability requires one combat action and lasts for the entire melee. It affects all sensor systems within a radius of 200 mile (321.7 km) in an atmosphere or 500,000 mile (804,672 km) in space. This ability only works on common sensor systems, such as radar and electromagnetic detection, and not on rare or unusual systems.