AN/ASQ-239 Barracuda

Cockpit, radar, helmet-mounted display, and other avionics
  • Author
  • Message
Offline

disconnectedradical

Forum Veteran

Forum Veteran

  • Posts: 894
  • Joined: 31 Dec 2010, 00:44
  • Location: San Antonio, TX

Unread post13 Apr 2020, 16:51

ricnunes wrote:The "marketing video" clearly shows that the barracuda listens in the broadband radio spectrum and listens most if not all the entire radio spectrum which is represented by colors ranging from red on the lowest radio spectrum to violet on the highest radio spectrum.
Despite being a "marketing video" like you said, there's no reason to believe that BAE is "lying on the video" regarding this.

Older EW/RWR are demonstrated to be able to listen a wide area of the radio spectrum so it would be stupid if the F-35 Barracuda didn't listen in a wider area compared to older systems.


Of course F-35 covers a range in the radio spectrum, that's why it's got different band antennas. That doesn't mean you can just use a marketing video graphic meant for illustrative purpose rather than pointing out specific frequencies and use that to correlate that with unrelated image that use a red to violet strip to help visualize different frequencies. So no that video and graphic does not tell you how low frequency F-35's antennas go, never said BAE was lying. I don't know why you're so defensive.

Also physically impossible for F-35 to cover entire radio spectrum, because of limitations of antenna size. But it doesn't need to and can still be effective. You can be more effective than older systems even if you don't cover everything the older system has.

ricnunes wrote:And I don't think we should be overly pessimistic about what the F-35 does and above all I don't think it's reasonable to expect that the F-35 won't perform much better that older aircraft or expect that it will perform worse than older aircraft.

I do think we should really, really be overly optimistic about everything F-35 does specially when it comes to electronics/sensors/etc... If this wasn't the case then this would be a singularity in the history of military aviation!

Resuming, it would be stupid to believe that the newer doesn't perform much better than the older.


Newer and better performing doesn't necessarily mean it covers every frequency as older systems. Like how some ship search radars went from L-band to S-band, so it doesn't cover the frequency of the older system but still a much better. So again I don't know why you always get so defensive about this.

F-35 probably has separate antennas for VHF, I doubt band 2 is low enough for that.
Offline
User avatar

ricnunes

Elite 2K

Elite 2K

  • Posts: 2687
  • Joined: 02 Mar 2017, 14:29

Unread post13 Apr 2020, 22:12

disconnectedradical wrote:F-35 probably has separate antennas for VHF, I doubt band 2 is low enough for that.


As you can see in eloise's last post band 3 covers as low as 0.5 GHz or 500 MHz if you prefer. That's well within the lower wavelength of the UHF band and very close to the upper wavelength of the VHF band which is 300 MHz. So it's logical that Band 2 which covers a lower wavelength compared to Band 3 covers VHF band quite well enough.

Moreover with emerging threats such as the Nebo-M VHF radar which is well known by the US and its allies, it's logical (together will all that was mentioned before) that the F-35 EW/RWR covers the VHF band as well.
“Active stealth” is what the ignorant nay sayers call ECM and pretend like it’s new.
Offline

eloise

Elite 1K

Elite 1K

  • Posts: 1833
  • Joined: 27 Mar 2015, 16:05

Unread post14 Apr 2020, 03:08

spazsinbad wrote:Would be nice to have a LINK to the BALL Aerospace F-35 Antennae graphic please. I looked at with nothing found there: https://www.ball.com/aerospace/programs ... ghtning-ii

https://www.scribd.com/document/1511861 ... JSF-SATCOM
Offline

eloise

Elite 1K

Elite 1K

  • Posts: 1833
  • Joined: 27 Mar 2015, 16:05

Unread post14 Apr 2020, 03:23

It doesn't help that different brochure and advertising video from Lockheed Martin also illustrate different length for Band 2 array.
In this clip, we see a much longer band 2 array at the base of the horizontal stabilator and another 2 antennae at the top of the vertical stabilator, something we never saw before

antenna.PNG

Capture.PNG
Offline
User avatar

spazsinbad

Elite 5K

Elite 5K

  • Posts: 24394
  • Joined: 05 May 2009, 21:31
  • Location: ɐıןɐɹʇsn∀¯\_(ツ)_/¯
  • Warnings: -2

Unread post14 Apr 2020, 03:40

eloise wrote:
spazsinbad wrote:Would be nice to have a LINK to the BALL Aerospace F-35 Antennae graphic please. I looked at with nothing found there: https://www.ball.com/aerospace/programs ... ghtning-ii

https://www.scribd.com/document/1511861 ... JSF-SATCOM

Downloaded it. Thanks very much.
A4G Skyhawk: www.faaaa.asn.au/spazsinbad-a4g/ & www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/videos?view_as=subscriber
Offline

eloise

Elite 1K

Elite 1K

  • Posts: 1833
  • Joined: 27 Mar 2015, 16:05

Unread post14 Apr 2020, 04:04

Very strange that even though we can find their location, MADL antennae are not included in the official CNI and EW antennae map published by Lockheed martin
50ce9c780f38e666bf29.jpg

MADL.PNG


Another strange thing is the mentioning of non-MADL electronic attack mechanism in block 4. Does that mean normal MADL antennae can do electronic attack?
F35-TH18-Block4.png

RclUR2V.jpg


spazsinbad wrote:
eloise wrote:
spazsinbad wrote:Would be nice to have a LINK to the BALL Aerospace F-35 Antennae graphic please. I looked at with nothing found there: https://www.ball.com/aerospace/programs ... ghtning-ii

https://www.scribd.com/document/1511861 ... JSF-SATCOM

Downloaded it. Thanks very much.

You are welcome
Offline
User avatar

Dragon029

Elite 1K

Elite 1K

  • Posts: 1381
  • Joined: 22 Dec 2014, 07:13

Unread post14 Apr 2020, 05:34

Good catch on the F-22 bands; those seem more reasonable, although I'm a little suspect about Band 3 supposedly covering such a wide range of frequencies; the book that the table comes from mentions that it "has been compiled with the help of the Joint Advanced Strike Technology Program Avionics Architecture Definition of 8 August 1994 and 9 August 1994. It is representative of the JIAWG/F-22 implementation and serves the purpose of demonstrating the RF architecture integration advances over the past decade or so.", so it's possible that the F-22's systems changed between then and when the slides describing F-22 EW aperture locations / bands were released.

As for non-MADL electronic attack; we ultimately have no idea, but I wouldn't be surprised if it's more referring to the utilisation of MADL (or in the future, other data links) to command or control electronic attack functionality (such as to perform cooperative jamming), as that in particular would explain why it it's listed at least once under the "Interoperability" column.
Offline

optimist

Elite 1K

Elite 1K

  • Posts: 1248
  • Joined: 20 Nov 2014, 03:34
  • Location: australia

Unread post14 Apr 2020, 14:19

At the time on this forum. The f-22 had many single band.frequency antenna, the f-35 had fewer multiple band/frequency antenna. We can only go by the spec sheets. I wouldn't believe they told the truth about EW/EA
Aussie fanboy
Offline

eloise

Elite 1K

Elite 1K

  • Posts: 1833
  • Joined: 27 Mar 2015, 16:05

Unread post14 Apr 2020, 14:49

So it is possible to make anti radiation missile home on VHF radar?


TECHNOLOGY AREAS: Sensors, Electronics, Battlespace, Weapons

ACQUISITION PROGRAM: PMA-242 Direct and Time Sensitive Strike Weapon Program
PMA-242.PNG

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), which controls the export and import of defense-related material and services. Offerors must disclose any proposed use of foreign nationals, their country of origin, and what tasks each would accomplish in the statement of work in accordance with section 3.5.b.(7) of the solicitation.

OBJECTIVE: Develop and demonstrate conformal antennas suitable for a number of existing missile airframes which are capable of transmitting and receiving an ultra wide bandwidth of frequencies.

DESCRIPTION: Innovative conformal antenna designs are being sought which are capable of operating in two specific bands of interest. The lower band covers the frequencies of 30 Mega Hertz (MHz) to 1000 MHz (the first Radio Frequency (RF) port) and the other band covers 960 MHz to 2000 MHz (the second RF port).

Current weapon antennas are confined to narrow bands and are directional. Software Defined Radios (SDR) are becoming the choice for data terminals for weapons. SDRs avoid costs associated with hardware changes for weapons that are in storage for up to 20 years. To allow the upgrades to SDRs, comparable antennas are needed to allow new spectrum utilization. Also, the Network Enabled Weapons (NEW) need to operate in an omni-directional environment to allow simultaneous link completion with as many network nodes as is possible.

Conformal antennas are needed to mount on existing missile bodies. The introduction of new antennas cannot produce new aero structures as that would force redesign of propulsion systems, force redesign of control surfaces, and force expensive recertification of the airframe. These antennas will be installed on existing airframes. The fundamental designs will need to scale to be accommodated on multiple missile airframes. The following are design goals for the conformal antennas:
Size - Conformal, with depths less than 0.7 inch. The anticipated missile diameters will range from a minimum of 9 inches to a maximum of 21 inches.
Weight - These antennas will need to be retrofitted on existing airframes. The combined weight of the antennas cannot exceed 5 lbs.
Bandwidth - Two bands are of interest. The lower band covers 100 MHz to 1000MHz and the other covers 960 MHz to 2000 MHz. The Voltage Standing Wave Ratio (VSWR) needs to be equal to or less than 2:1.
Antenna Pattern - Threshold: Less than 2 decibel isotropic (dBi) variance Goal: Omni over the entire bandwidth. Antenna gains for legacy waveforms will need to be the same or better than existing antennas. Polarization - Vertical relative to skin of weapon airframe.
Materials - Temperatures need to withstand high speed (supersonic) flight and need to be highly repeatable for manufacturing purposes.
Power - This is a transceiver and both antennas will need to handle a nominal power of 90 Watts with a maximum of 125 Watts.
Structural - The installation of the antennas cannot degrade the structural integrity of the weapon all up round. Ideally, it would not be a stressed airframe component. Analysis will need to be done to show that it will not degrade structural integrity.

PHASE I: Demonstrate proof of concept antenna design using modeling and simulation to characterize the performance of the antenna relative to the design goals listed above.

PHASE II: Based on the results from Phase I, design a prototype conformal antenna and demonstrate its performance in a laboratory environment.

PHASE III: Develop an engineering model of the antenna and integrate with a notional missile. The goal is the Advanced Anti Radiation Guided Missile (AARGM) and flight test with Office of Naval Research (ONR) Weapons Data Link (WDL) terminal.


https://www.navysbir.com/n10_3/N103-204.htm
Offline

eloise

Elite 1K

Elite 1K

  • Posts: 1833
  • Joined: 27 Mar 2015, 16:05

Unread post16 Apr 2020, 04:04

I figured out what is the antenna at the end of the vertical tail
antenna.PNG

Northrop Grumman has been developing "smart" structures and related technologies for aircraft and unmanned aerial vehicles since the late 1980s. The company is currently exploiting its earlier success with CLAS technology to integrate load-bearing antennas in critical structural components of the F-35 Joint Strike Fighter.

https://news.northropgrumman.com/news/r ... nd-targets
Previous

Return to F-35 Avionics

Who is online

Users browsing this forum: No registered users and 4 guests