TEL AVIV — Israeli defense officials, who were frustrated by their inability to silence Hezbollah television broadcasts during an unsuccessful five-week campaign to roust the Islamist group from southern Lebanon, have identified a need to be able to disrupt transmissions of enemy programming carried by commercial satellites.

Despite directly targeting Hezbollah leader Hassan Nasrallah and the organization’s Al-Manar TV network with bombs and electronic warfare, Israel was unable to prevent the radical Shiite cleric from reaching his audience on a regular basis. In interviews at Israel Defense Forces (IDF) headquarters here and at Israel’s Galilee-based Northern Command, officials said Nasrallah’s public resilience in the face of the onslaught had given a morale boost to Hezbollah’s fighters and sympathizers.

“We struck their antennas, which prevented transmissions for a limited time. We also succeeded in penetrating their broadcasts and inserting our own programming. But at the higher level, it’s very difficult to block their satellite communication, since they’re constantly changing their signals,” said Shuki Shacur, a brigadier general in the IDF Reserves who served as deputy commander for Northern Command for the duration of the war.

“After the war is over, we’re likely to see more effort invested in denying Hezbollah its ability to use this means of communication,” Shacur said.

Brig. Gen. Ido Nehushtan, an Air Force officer on the IDF General Staff, agreed. “No doubt, we understand the power of the media, public opinion and mass psychology. Al-Manar is a liability, and we’re going to have to improve our ability to counter this threat,” said Nehushtan, who recently received his second star and is now responsible for IDF modernization planning.

In an Aug. 2 interview, Nehushtan declined to elaborate on potential broadcast-denial solutions or developmental work presumably under way within Israel’s Ministry of Defense (MoD). He acknowledged, however, that jamming efforts thus far have not been directed at commercial satellites servicing Al-Manar.

“We’ve done some jamming and have managed to burst through broadcasting, but it’s been through local channels, not satellite signals,” he said, declining to elaborate.

Jamming transponders on a commercial satellite is a relatively easy thing to do, especially for a technically advanced country like Israel, but would carry negative repercussions internationally and could invite others to disrupt transponders on Israel’s own satellites. It was not clear exactly what the IDF official had in mind in suggesting the need for a way to disrupt the Al-Manar broadcasts.

Tal Inbar, senior research fellow at Israel’s Fisher Institute for Air & Space Studies, said the war revealed limitations in Israel’s ability to silence Al-Manar. Conventional bombing is ineffective, he said, due to Hezbollah’s ability to transmit from cars or trucks.

“It’s very difficult, almost impossible, to hit all those mobile transmitters,” he said.

Inbar noted that at the outset of hostilities, Israeli aircraft destroyed Al-Manar’s five-story headquarters in south Beirut. “But thanks to elaborate advance planning, Al-Manar’s signal returned after just two minutes of downtime,” he said.

Inbar insisted the only way to ensure persistent, reliable, wide-area broadcast denial is through a satellite-signal jamming system. “We urgently need to have the ability to jam the [satellites] transmitting Al-Manar broadcasts.” According to Inbar, Israel must develop the means to surgically target only those signals serving H ezbollah without damaging the spacecraft or disrupting operations of other customers serviced by the broadcast frequencies.

Israeli military and industry sources said other broadcast denial methods employed during the conflict, such as computer-based tampering, have met with some success.

“It was a desktop operation. We didn’t jam it; you can easily jam it. What we did was implant our own content on a fairly broad scale in a way that was difficult for them to override,” a former MoD official told Space News. He declined to provide additional operational or technical details, and Israeli authorities denied repeated requests for information on broadcast denial capabilities.

An Israeli industry executive and former Israel Air Force officer specializing in satellite technology confirmed that Israel did not jam commercial satellites during the war. “I’m not saying we don’t have this capability, but we haven’t been able to do this in a way that does not interfere with other users of the satellite,” he said. According to the executive, jamming a communications satellite is “like interfering with civil aviation. You can do it, but it’s against international law and you’ll be subject to all kinds of lawsuits.”

He added that it is technologically impossible to selectively jam only those satellite signals that carry enemy broadcasts. “Everything goes out as a single beam, and it is impossible to jam only those channels viewed as a threat. If you make the decision to interfere with one [satellite signal], then you must be prepared to face the consequences of the collateral damage incurred to the many other legitimate users of the signal,” he said.

Robert Ames, chief executive of the Satellite Users Interference Reduction Group, a Punta Gurda, Fla.-based industry association, said it is relatively easy to jam a specific satellite transponder. “Transponders are separated by frequency. So all you have to do is know the frequency which it operates on and then put up a signal that is stronger than the programming carrier of the satellite. That’s all it takes to override the signal,” he said.

“This occurs globally on perhaps a monthly basis, typically due to political or religious disagreement between countries or organizations. They make their discomfort known through intentional jamming,” said Ames. He added that satellite interference capabilities have been around since the mid-1970s. “But if the Israelis are talking about technological challenges, I assume they are aiming for a capability that goes way beyond what our companies have experienced to date.”

Satellite industry experts, who generally are tight-lipped on the subject of jamming due to the sensitivities involved, said overwhelming an entire transponder with signals beamed up from the ground is far easier than trying to surgically deny broadcast signals over a given geographic area.

Doron Tamir, a retired IDF brigadier general and former chief intelligence officer, questioned whether developing the means to surgically jam satellite broadcast signals is worth the cost. “You can come up with all kinds of systems for high-power, wide-area jamming. But the dilemma remains: Will it be cost effective? Is it truly needed?”

In an Aug. 10 interview, Tamir, a fellow at the Herlzliya, the Israel-based International Policy Institute for Counter-Terrorism, said war planners often benefit from Al-Manar and other broadcasts in ascertaining nuances about enemy capabilities and intentions. “I think it would be a mistake to consistently deny the enemy this capability over the long term. Perhaps it’s better to hold [an ability to disrupt satellite signals] in reserve, and deploy it only at a time when it can contribute the optimum impact to our own war effort,” he said.

An Israeli defense expert here suggested that the IDF may ultimately pursue what he called an on-demand counter-satellite capability deployed aboard a long-endurance unmanned aerial vehicle.

Requests for information concerning Israeli broadcast-denial capabilities were rejected by Israel’s MoD. “The entire subject is classified. That’s our policy,” said MoD spokeswoman Rachel Naidek-Ashkenazi.

Lebanon’s Daily Star newspaper estimates that Al-Manar reaches up to 200 million viewers through satellite packages offered by the Arab Satellite Communications Organization (Arabsat) of Riyadh, Saudi Arabia, and partner firms. Al-Manar broadcasts are also carried by Egypt’s Nilesat, Israeli experts here said.

In 2004, the U.S. government declared Al-Manar a terrorist entity and barred broadcasting of its signal to the United States. Since then, several European governments, including France and Germany, have also banned Al-Manar transmissions.