What was happening in Gaza City’s al-Jalaa Building during the latest upsurge in violence between the Israeli government and Hamas?
Israel’s military says that it gave the occupants one hours’ notice. Just over one hour late, the al-Jalaa Building in Gaza City was a memory. The eleven-story tower felled by air-to-surface ordnance launched by Israeli Air Force (IAF) aircraft on 15th May.
The al-Jalaa was another casualty in the latest flare-up between the Israeli government and the Islamist Hamas insurgent organisation controlling the Gaza Strip. The IAF’s attack generated controversy. Alongside residential apartments, international media organisations Al-Jazeera and Associated Press had their bureaux in the building.
A statement released by the Israeli Defence Force (IDF) soon after the strike acknowledged that the building included “civilian media offices” while accusing Hamas of using human shields. The statement alleged that the insurgents were using the tower for Signals Intelligence (SIGINT), Electronic Intelligence (ELINT) and Electronic Warfare (EW) operations. The statement did not elaborate on what these SIGINT/ELINT or EW capabilities might have been.
It is all but impossible to independently verify whether the building was used by Hamas for these purposes. A cursory look at pre-attack photographs of the tower show several antennas on its roof. Were some, if not all, of these used by the media outlet occupants to send and receive live reports and video footage? Some of the microwave arrays could have also been used for local telecommunications coverage.
Nonetheless, if an organisation wished to disguise SIGINT/ELINT receiving antennas, hiding these in a multitude of civilian antennas is probably not a bad idea. If the IDF had deduced that it was being used by Hamas for SIGINT collection, one can see why the al-Jalaa building would be a target. Camouflaging a SIGINT operation among media organisations innocently using the electromagnetic spectrum has obvious attractions.
Iron Dome
A further allegation made by the IDF was that Hamas was developing equipment to “disrupt the Iron Dome” Surface-to-Air Missile (SAM) system. Developed by Rafael Advanced Defence Systems and Israel Aerospace Industries (IAI), Iron Dome was instrumental in protecting Israelis during this latest conflict. Open sources state that Iron Dome successfully intercepted circa 90 percent of Hamas rockets aimed at populated areas in Israel.
What electronic attack systems could Hamas have brought to bear against Iron Dome? The overall SAM system comprises several elements relying on the electromagnetic spectrum. These include IAI’s EL/M-2084 S-band (2.3 gigahertz/GHz to 2.5GHz/2.7GHz to 3.7GHz) ground-based air surveillance/fire control radar. This acquires targets for the missiles and helps guide them to their quarry. A combined Identification Friend or Foe (IFF) interrogator will send and receive interrogations and responses to aircraft detected by the radar. The IFF will use frequencies of 1.030GHz and 1.090GHz. The battery will communicate with missiles once launched via a radio frequency datalink. Very/Ultra High Frequency (V/UHF: 30 megahertz to three gigahertz) radio links connect the disparate elements of the battery alongside higher and subordinate echelons. An encrypted GNSS (Global Navigation Satellite System) will help provide precise location and timing information. GNSS data will almost certainly be military-grade encrypted ‘M Code’ transmitted by the US Global Positioning System on frequencies of 1.164GHz to 1.575GHz.
Jam Sandwich
Potentially any and all these elements could be at risk from electronic attack. However, a successful electronic attack against the Iron Dome would be no mean feat. All these elements will have numerous electronic counter-countermeasure safeguards. Radar and radio communications will use techniques like frequency hopping and low probability of detection/interception. V/UHF and missile communications, along with the GNSS, will be encrypted.
Confidential sources have told Armada that Hamas has worked hard to obtain Iranian electronic warfare equipment and assistance. Iran claims to have enjoyed success with GNSS jamming and cyberattack. For example, on 5th December 2011 both were claimed to have been instrumental in capturing a US Air Force Lockheed Martin RQ-170 Sentinel unmanned aerial vehicle flying in the vicinity of the Afghan-Iranian border. Whether Hamas has secured such technology is unknown. Even if it had there is no indication that this would be effective against Iron Dome. The Persian Gulf regularly hosts US and Allied warships equipped with sophisticated radars and radio communications. There appears to be no information in the public domain that Iran has enjoyed any success in jamming these systems.
Jamming does not have to be successful to constitute a threat. Israeli SIGINT experts may have detected attempted electronic attack and identified this as being from the al-Jalaa tower. Even if the jamming was unsuccessful, a decision may have been taken by the IDF to attack the building to stop further attempts.
Armada spoke to two electronic warfare experts asking them what they believe were Hamas’ most likely electronic attack targets. One flagged GNSS signals used by the Iron Dome battery, along with communications links between the battery’s command post and launchers. However, they cautioned that attacking these would be difficult. They noted that the Iron Dome uses highly directional antennas for GNSS and ground-to-ground communications. Hamas would need to use high gain antennas to direct any attack with requisite precision against the Iron Dome’s antennas. The source added that such high gain antennas would be relatively easy to spot. To an airborne synthetic aperture radar “they would have a relatively high backscatter with the ground.” They would be seen as “bright, reflective spots on a concrete building or structure.”
Armada’s other expert concurred that GNSS might have been Hamas’ target, but argues that Iron Dome’s dependence on this is minimal: “The only GNSS data needed by Iron Dome would be for the radar installation position.” Instead, Hamas may have tried to use GNSS jamming “to falter/degrade any GNSS-guided bombs” used by the IAF during the airstrikes. Rafael’s SPICE (Smart, Precise Impact, Cost-Effective) precision-guided munitions deployed by the IAF uses several guidance systems including GNSS, alongside optronics and an inertial navigation system. Although such weapons can still hit their targets sans one of these guidance systems the IDF may have felt that the risk of GNSS disruption constituted too much of a threat to IAF airstrikes.
Early Warning
Another potential target of Hamas jamming might have been the Israeli air raid warning system. Part of this network includes software applications which can be used by smartphones to warn of incoming raids. Armada’s source believes that “the segment Hamas was trying to jam was the GSM (Global System for Mobile Communications) population warning system to maximise human casualties” from Hamas rocket attacks: “This pissed off the Israelis.”
Unless either the Israeli government or Hamas come clean on what was in the al-Jalaa building we may never know the extent of Hamas’ electromagnetic aspirations during the recent fighting. IDF public statements do indicate that Hamas’ interest in electronic warfare successful or otherwise, is being taken seriously. Further attempts by the militia to harness electronic attack in future peace and war cannot be ruled out.
by Dr. Thomas Withington