Pepê,
Antes de mais nada não sou defensor do Gripen NG para a FAB. Mas também não sou, a princípio, contra. E também estou ciente que dentre os 3 é a opção de maior risco. Mas...
A Saab Microwave (ex-Ericsson Microwave Systems) tem desenvolvido tecnologias AESA há muito tempo: NORA e Erieye principalmente.
O Ericsson PS-46/A do JA-37 Viggen foi o primeiro radar pulse doppler de projeto europeu a entrar em serviço.
Em 2003, a Ericsson Microwave System comprou uma antena AESA da Raytheon para testes e foi usada para desenvolver o processador de sinais e arquitetura do sistema (vide texto abaixo). Na europa não havia quem pudesse fornecer isso.
A Selex Galilo não necessita de apresentações. Basta dar uma pesquisada na sua herança empresarial e tecnológica: Plessey, Marconi, Ferranti, Fiar, GEC, etc.
Diferentemente da Thales, Saab e Selex já fabricam radares AESA.
Saab e Selex possuem cada uma mais de 50 anos de experiência no projeto e fabricação de radares de controle de fogo.
O novo radar do Gripen possui uma nova antena (AESA) e o backend é uma evolução do provado PS05. Mesma estratégia adotada pela Thales com o RBE2.
O Vixen 500 nada tem a ver com o radar do Gripen NG. Assim como nada tem a ver com o Blue Vixen do qual derivou o Captor e de certa maneira o PS05.
Será que a Saab/Selex desaprenderam a fazer um bom radar? Será que a antena AESA da Selex fez mal ao provado backend? Será que a antena da Thales faria melhor?
Trecho de um antigo artigo de Bill Sweetman sobre o PS05:
But the use of the link goes beyond this, towards what the Swedish Air Force calls "samverkan," or close-cooperation. One example is the use of the Ericsson PS-05/A radar with TIDLS. An Ericsson paper compares its application, with identical sensors and precise knowledge of the location of both platforms, to human twins: "Communication is possible without explaining everything."
"Radar-samverkan," the Ericsson paper suggests, equips the formation with a super-radar of extraordinary capabilities. The PS-05/A can operate in passive mode, as a sensitive receiver with high directional accuracy (due to its large antenna). Two PS-05/As can exchange information by datalink and locate the target by triangulation. The target's signals will often identify it as well.
The datalink results in better tracking. Usually, three plots (echoes) are needed to track a target in track-while-scan mode. The datalink allows the radars to share plots, not just tracks, so even if none of the aircraft in a formation gets enough plots on its own to track the target, they may do so collectively.
Each radar plot includes Doppler velocity, which provides the individual aircraft with range-rate data. However, this data on its own does not yield the velocity of the target. Using the TIDLS, two fighters can take simultaneous range-rate readings and thereby determine the target's track instantly, reducing the need for radar transmission.
In ECM applications, one fighter can search, while the wingman simultaneously focuses jamming on the same target, using the radar. This makes it very difficult for the target to intercept or jam the radar that is tracking him. Another anti-jamming technique is for all four radars to illuminate the same target simultaneously at different frequencies.
O texto abaixo de 2007 é anterior ao acordo de uso da antena AESA da Thales para o desenvolvimento do radar AESA pela Saab. Em 2006 já havia acordo entre a Saab e Selex para desenvolver conjuntamente um radar AESA, e na época já estava delineado o conceito "swashplate".
M-AESA for the Gripen
In Sweden, aesa programs have been running for many years in the hands of Saab (formerly Ericsson) Microwave Systems at its Gothenburg facility. Early development was conducted under the nora (not only a radar) and eliNt (electronic signals intelligence) programs and involved development of X-band T/R modules and test arrays. Development aesa arrays have also been extensively trialed on the ground, and in a pod mounted on the ramp of a C-130 Hercules military transport.
In 2001 Ericsson won a development contract from FMV, the Swedish Defence Material Administration, and the same year it signed a deal with Raytheon under which the U.S. company would supply a complete aesa array for installation on the back end of the Gripen’s PS-05/A radar. Delivered in June 2004, it was due to be installed in a Viggen for trials in mid-2005, but the early retirement of the Viggen from service resulted in a delay to the trials and a switch to another platform.
Tests of the Raytheon scanner are being undertaken as part of the nora program, which aims to provide an aesa radar for the Gripen. As its name implies, nora is also investigating the use of the antenna for functions such as communications and jamming, as well as its radar tasks.
Saab is working toward a PS-05/A Mk 5 aesa radar that could be available for export around 2010. The Mk 5 would focus primarily on its radar functions. Beyond that the company is looking at more developments that tightly integrate the functions of active radar, passive surveillance, electronic warfare, jamming and communications into a single sensor. The sensor could be mounted on a single-axis pedestal that would increase its scan to around 200 degrees. Such a multifunction nora radar could be ready for installation in Gripen around 2018. In November 2006, Saab Microwave systems signed with Italian companies Selex and Elettronica to jointly develop an M-AESA multirole system concept. This will be used as a basis for the next family of radars for a wide range of applications, including combat aircraft.
Fonte:
http://www.ainonline.com/news/single-ne ... 40247a0c96
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