4 juin 2021 | International, Aérospatial

Multibeam antenna to improve communication passes first Air Force trials

The prototype antenna will be able to connect to multiple satellites simultaneously in different orbital ranges.

https://www.c4isrnet.com/battlefield-tech/space/2021/06/03/multibeam-antenna-to-improve-communication-passes-first-air-force-trials

Sur le même sujet

  • DoD Pushes To Reverse FCC OK Of Ligado 5G Network

    11 mai 2020 | International, C4ISR

    DoD Pushes To Reverse FCC OK Of Ligado 5G Network

    "The impact is significant, and it's unacceptable," Gen. Jay Raymond told the Senate Armed Services Committee. By THERESA HITCHENSon May 06, 2020 at 8:14 PM WASHINGTON: DoD is pressing for the FCC to reverse its controversial decision to approve Ligado's plan to create a mobile 5G communications network, one the Pentagon asserts will jam GPS receivers. “It is clear to DoD that the risk to GPS far outweighs the benefits of this FCC decision. And the FCC needs to reverse their decision,” DoD CIO Dana Deasy told the Senate Armed Services Committee (SASC) hearing during a marathon hearing this afternoon. A formal “re-petition” action has to be taken by National Telecommunications and Information Administration (NTIA) by the end of May. NTIA, which falls under the Commerce Department, coordinates federal agency use of the radio frequency spectrum. DoD, Deasy told the SASC, is working to provide NTIA with the necessary technical information to do so. SASC members were divided on the wisdom of the FCC's April 20 decision to approve Ligado's latest plan to repurpose its current L-band spectrum for use in a US-wide terrestrial 5G network. The SASC hearing did not fall along partisan lines. Instead, the division came between the SASC leadership and the committee's members who also sit on the Senate Commerce, Science and Transportation Committee. It has jurisdiction over the FCC. For example, while Republican SASC Chairman James Inhofe and Democratic Ranking Member Sen. Jack Reed excoriated the FCC decision, Republican Sen. Roger Wicker, who chairs the Commerce committee, expressed support for the FCC. Indeed, a number of senators with a foot in the Commerce Committee raised the fact that the FCC's decision not only was approved unanimously by the five FCC commissioners, but also has been praised by Secretary of State Mike Pompeo and Attorney General William Barr. (Barr was tapped by President Donald Trump on April 4 to head a new Telecom Team designed to ensure that China cannot dominate the 5G marketplace and undercut the security of emerging US networks.) DoD and many other agencies, including the Transportation Department, have opposed the planned Ligado (formerly LightSquared) network for nearly a decade, arguing that it will drown out GPS signals in most current receivers. Their protests have been echoed by a wide swathe of the defense and commercial transport industry, including the Aerospace Industries Association and the National Defense Industrial Association. Indeed, according to a press release put out today by Inhofe's office: “This opposition extends to the private sector as well. Numerous industries across the gamut – commercial air, satellite communications, weather, construction, and more – have also registered their objections to the FCC's Order.” Mike Griffin, head of DoD Research and Engineering, explained that the issue is the “noise” that will be created by Ligado because it will use spectrum designed for satellite use to rebroadcast via terrestrial cell towers. He said that the situation for the vast number of GPS receivers today would be analogous to trying to hear the “rustling of leaves” through the noise of “100 jets taking off all at once.” Perhaps most significantly, Griffin pushed back hard against Ligado's assertions in FCC filings (and most recently in a letter today to the SASC obtained by Breaking D) that most receivers would not be affected. He said testing done by the Transportation Department showed that high-end GPS receivers used in civil aviation, which costs some $10,000 each, are impacted by Ligado's planned signal strength. Even those “hardened” receivers are “barely capable” of discerning GPS signals through the “noise” caused by Ligado's 9.8 dBW — an energy level about equal to that put out by a 10 watt light bulb). More worryingly, Griffin asserted that most commercial GPS receivers — including those that would be used to guide self-driving cars in the future — “lose lock” on the signal at a power level some 100 times lower than Ligado plans to use. Gen. Jay Raymond, double hatted as the head of Space Force and Space Command, told the SASC that Ligado's network would have a “significant impact” on Dod's homeland defense mission, as well as on military and commercial space launch capabilities. “In my opinion, the impact is significant, and it's unacceptable,” he said. While Deasy said one avenue for reversing the decision could be legislative action, it remains unclear what the SASC can actually do, however — should the committee even be able to agree on a course of action. Inhofe said it is legally unclear to him right now whether the Congressional Review Act, that allows Congress to overturn a decision by a federal agency, actually applies to the FCC decision for technical reasons. (The FCC officially is independent of the Executive Branch.) Retired Adm. Thad Allen, former Coast Guard Commandant and chair of the Space-Based Positioning and Timing National Advisory Board, suggested that the Senate Commerce Committee should hold a hearing and force the FCC to reconsider. Those members of that committee participating today, including Wicker, seemed reluctant to consider the idea of even having an exploratory hearing. For example, Democratic Sen. Richard Blumenthal suggested that the matter perhaps might be better adjudicated in the courts, given the questions raised about the legalities of the FCC's administrative process that have been raised by members of Congress as well as several industry groups. https://breakingdefense.com/2020/05/dod-pushes-to-reverse-fcc-ok-of-ligado-5g-network/

  • China's military lashes out at US after breakthrough talks

    28 décembre 2023 | International, Sécurité

    China's military lashes out at US after breakthrough talks

  • BAE Systems to supply assault amphibious vehicles to Taiwan

    27 juin 2018 | International, Terrestre

    BAE Systems to supply assault amphibious vehicles to Taiwan

    Gabriel Dominguez BAE Systems has been awarded a USD83.6 million contract to provide to Taiwan the “necessary material and technical engineering to build, integrate, test, and deliver” 36 AAV7A1 Assault Amphibious Vehicles. The contract is for 30 AAVP7A1 personnel carriers, four AAVC7A1 command post vehicles and two AAVR7A1 recovery vehicles, according to a 22 June announcement by the US Department of Defense (DoD). This deal, which involves Foreign Military Sales (FMS) under the Taipei Economic Cultural Representative Office (TECRO) – FMS case TW-P-SEQ – also includes support and test equipment, spares, publications, training, engineering services, logistics, and other technical support required. All work will be performed in York, Pennsylvania, and is expected to be completed by 22 July, 2020, said the DoD, adding that this contract “was not competitively procured in accordance with Federal Acquisition Regulation 6.302-1(a)(2)(ii) - only one responsible source and no other supplies or services that will satisfy agency requirements”. The contracting authority is the US Marine Corps Systems Command in Quantico, Virginia. Once delivered, the AAV7A1s are very likely to be used by the Republic of China Marine Corps (RoCMC), but will not be the first ones to be operated by the Corps. In 2003 Taiwan signed a contract for 54 ex-US Marine Corps AAV7A1-series vehicles that have begun replacing the LVTP5 series of amphibious fighting vehicles used by the RoCMC. The latest contract announcement comes a few weeks after Taiwan said it welcomed a potential shift in policy by the United States' government to facilitate military sales to the island on a case-by-case basis as opposed to the current approach of ‘bundling' several defence deals together, as Jane's reported. The Ministry of National Defense (MND) in Taipei said in comments reported by the state-owned Central News Agency on 5 June that any US transition to approving FMS requests separately would improve its ability to plan and budget military modernisation requirements. http://www.janes.com/article/81335/bae-systems-to-supply-assault-amphibious-vehicles-to-taiwan

Toutes les nouvelles