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I am working on a project where we have decided to use radar to measure the distance of an object from the device.

I have been using Infineon's BGT24MTR11 (24GHz) evaluation board, (Sense2go), which comes with an integrated patch antenna already onboard.

enter image description here

It will detect movement approximately 5m from the board.

However, we need to accurately measure the distance of objects approximately 100m from the transmitter and have a required detection radius of 10°.

There are issues around 24GHz, (temporary band, astronomy stations, etc.), so we may actually move to 77GHz or 79GHz but for the moment I am sticking with 24GHz.

edit As kindly pointed out by Brian Drummond the sense2go module will not measure 100m, so the 24GHz is not an option and sense2go is off the list .

enter image description here

The regulatory body ETSI, lists only three automotive radar frequencies, 24, 77 & 79GHz, http://www.etsi.org/technologies-clusters/technologies/intelligent-transport/automotive-radar. 77GHz seems to be the most popular.

The next evaluation board on our list comes from Altera This has a centre frequency around 77GHz. I tried contacting the supplier of the demo antenna but they did not get back and the feedback I have been getting is that unless you are tier 1 or a major OEM they won't talk to you.

I have been looking in vain for commercially available antennas that will work at these frequencies.

Something like Delphi's system would be ideal.

I am considering designing the antenna using cst, however I have limited experience in antenna design and there are no antenna design experts on the team.

Can anyone make a recommendation for a best course of action (77GHz)?

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    \$\begingroup\$ Given the fourth power "radar law" you need to increase (transmit power * sensitivity) by (100/5) ** 4, or 160000 times. I don't think changing the antenna will do it. \$\endgroup\$ – Brian Drummond Dec 19 '15 at 17:22
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    \$\begingroup\$ At least if you do use a high gain antenna you get its benefit twice - on both transmit and receive, but it still looks like a challenge. I expect the FAE is in a better position to explain how to get the range he claims than we are. \$\endgroup\$ – Brian Drummond Dec 19 '15 at 18:04
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    \$\begingroup\$ Try putting the evaluation board at the focus of a small (1-2 foot) parabolic dish. \$\endgroup\$ – Dave Tweed Dec 19 '15 at 18:09
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    \$\begingroup\$ If there is no antenna design expertise on your team, I would recommend buying. Antenna design is not a trivial task for the uninitiated \$\endgroup\$ – johnnymopo Dec 19 '15 at 18:50
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    \$\begingroup\$ Especially at 77 GHz \$\endgroup\$ – johnnymopo Dec 19 '15 at 18:50
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At 77GHz the tolerances for "antenna" design are so small, that it would take a very experienced antenna designer to design such an antenna. Which in reality is a wave guide, not an antenna in the traditional term.

Stick with commercially available antenna systems: or stick the whole board in the focal position of a parabolic dish as suggested in the comments.

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Older post, but thought I'd offer an up to date response. I recommend checking out the Texas Instruments IWR and AWR FMCW 77GHz Radar SoC.

http://www.ti.com/sensing-products/mmwave/overview.html

The Boosterpack style EVM kits include all layout files, schematics and bill of materials. Demo software also included which provides simple range, velocity and angle of arrival estimation. These are examples of working 76-81GHz antenna, as well as GCPW transmission line, and BGA to transmission-line to get you started.

http://www.ti.com/tool/iwr1443boost

http://www.ti.com/tool/iwr1642boost

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