ネタ | Perfectjammer道場 | 学問・研究 | まにあ道

Bloody ground attacks by Hamas armed militants shocked Israel, but there were also surprises overhead, says a Brock University professor.

DRONES IN ISRAEL AND UKRAINE

This seems to be the first conflict where Hamas has successfully used armed drones. Some are quadcopters that operators fly via remote control. They can precisely drop explosives onto small targets - like an Iron Dome system. Videos online show them attacking people, a watchtower and a tank.

Ukraine has effectively used similar quadcopters against Russian military targets. They sometimes drop explosives right down an armoured vehicle’s open hatch.

However, technology is developing rapidly, in many cases, faster than the defence industry or NATO can react. For example, many ‘traditional’ countermeasures against small UAS rely on electronic jamming of the Command and Control (C2) link between the ‘drone’ and its remote control. Many current COTS products are, however, able to navigate autonomously to a given coordinate or can be controlled via a Global System for Mobile Communications (GSM) network from the operator’s mobile phone. These features make jamming either completely useless, since the C2 link is no longer required to navigate, or unavailable, because of peacetime restrictions that prohibit the signal jamming of frequencies that are in use by the public.

The Space Domain

SATCOM is an essential part of BLOS UAS operations. But COTS UAS also utilize PNT signals provided by respective satellite constellations. Within the limits of the ‘Outer Space Treaty’, countermeasures against space-based communications and PNT may be a legitimate option to defend against an entire fleet of adversary UAS. This does not necessarily require kinetic engagements by anti-satellite weapons. Indeed, ground or space-based jamming capabilities could be effective without risking the creation of large amounts of debris which could render entire orbits unusable for mankind.

Depending on the country and its domestic laws, which are applicable during peacetime, circumstances may prohibit certain types of countermeasures and limit the options for defending against UAS. These possibly prohibited countermeasures include kinetic engagement of airborne UA, cell phone jamming of publicly used frequencies such as GSM or wireless networks, or interference with the commercial PNT signals.

Additionally, non-kinetic measures such as jamming radio frequencies or PNT signals may affect public and commercial communications infrastructure and therefore, may be restricted or completely off-limits. Especially in peacetime, countermeasures have to be balanced against potential adverse impacts on critical communication systems and possible economic losses

Drug Cartels. In Mexico, drones have been extensively used for drug trafficking purposes in the region of the Mexico-US border as their use significantly lowers the risk of being caught. The route of the drone is pre-programmed and due to its autonomous capability, it cannot be blocked by electronic jammers at the border. The cartels in Mexico also use so-called potato bombs – hand grenadesized IEDs – in attacks on each other.

Both categories, commercially available drones as well as military UAS, should be considered ‘autonomous’ in the way that they probably no longer require a permanent command and control link to fulfil their mission. This eliminates many of the current countermeasures which rely on gps jamming their radio transmissions.

Most UAS use a dedicated PNT data link to determine its precise location, and this link must be maintained to ensure mission success. The PNT signal strength measured at the surface of the Earth is roughly equivalent to viewing a 25-Watt light bulb from a distance of 10,000 miles. This weak signal can easily be jammed by a stronger power transmission in a similar frequency.

Any radio navigation system is generally vulnerable to interference. A typical patch antenna used to receive PNT signals must be able to receive them from virtually the entire sky. The advantage of this omnidirectional design is that even signals from satellites, which are just above the local horizon, can be received. However, this design is susceptible to a broad range of interference and <i>drone jamming</i>.