AMiBA PROJECT WEEKLY MEETING MINUTES

Date: 9 November 2000

Participants: K.Y.Lo, B. Martin, H. Wang, W. Wilson, M. Sinclair, M. Kesteven, B. Sault, M.T. Chen, C.H. Lu, Y.J. Hwang, P. Shaw, J. Wang

Issues and Description	Action by			Output
General
1. Fred has visited NASA headquarter, and met the management lever in administration to Charles Lawrence/JPL. He explained them what we are doing, and hopefully any collaborate activity comes out. Let the NASA headquarter knows about this, and give us approval. So they will talk to Charles and Todd again about our request for loaning the InP HEMT MMIC.Todd showed Fred the lab, particularly showed him the amplifier which designed by Huei, and it looks working very good. 2. Regarding the export license, Fred thinks that we really should follow up on is the idea of whatever is done would ends up in Hawaii, we hope. And we should go for permission for borrowing the modules and any else we are working on, and that might make things easier. The other alternative of course is directly to ship it to Hawaii, and doesn't come to Taiwan at all. That means then we need to send people to Hawaii and work on that, so that is less convenience. 3.The Mauna Kea management is now installed a Institute of Astronomy in Mauna Loa ; the Mauna Loa Campus University in Hawaii, now taking care by Hilo Campus. The new development basically means the balance of power is shifting to Hilo as are the management of Mauna Kea. To put AMiBA on Mauna Kea, now we go through Hilo instead of Ma Lova. The Chancellor of UH in Hilo is Rose Tseng who grows up in Taiwan. So Fred thinks we have a sort of nature contact point. So Fred and Paul Ho had a meeting with she, they brought up an application for permission to put up the AMiBA on the Mauna Kea. Fred thinks that is a good development for our prospect. 4. Regarding the collaboration with Caltech for CBI and AMiBA, Fred has some discussion with Tony. Tony told Fred that he need to have a decision in a few months, and he needs substantial input of manpower and money to run the CBI telescope. Fred thinks the discussion of possible cooperation with CBI, it might not be happen.
MMIC- W- Band InP HEMT LNA
1. Huei says that the fabrication run in TRW for the 0.15£gm GaAs PHEMT process has been delivered to Taipei. This is his first iteration design on the Subharmonic Mixer designed by Eugene. Huei will bring the chips to Mal by early Dec. while he participates in the Microwave Conference in Sydney. Mal asks Huei to provide the relevant chip design data to him, and in the mean time he will check the program of the lab to see when they are able to measure that chip for Huei. Our target is to have all measurement results by late Dec. 2. Regarding the Sub Hamonic Mixer¡¦s chip test at ATNF, Huei asked Mal last week whether AT could make three more mixers isolation measurements. Mal says that they are planning to do at least two of those in late Dec. once they finish the installation of receiver. But on measurement has a lot of difficulties been doing, because of it requires a certain device, which they don¡¦t have. 3. Todd told Huei that he will send the first InP HEMT chip design to TRW in Nov.15, and he will send the wafer test result to Huei. 4. As for the 0.1um GaAs HEMT, Huei says the chip is ready shipped to TRW, and finally CIC signed the contract with TRW. 5. As to the export license application for the InP HEMT of TRW, Huei says Joyce told him that the review process is still ongoing at the State Department He is expecting to get a final decision on that issue by early November. Huei will follow up to see what happen. 6. Regarding the Wave-guide filter, Mal will provide some drawings to Huei , and Huei will forward this design information to Prof. Wu. 7. Leo got a HPF quotation from Quinstar; the price is $1,000USD for each, but it would be $250USD each if we once order 40 units; specs are 80.5~105GHz, 84GHz at 3dB cut off, insertion loss 27db at 82 GHz. They need 60 days to deliver the first 4 units, and another 30days to deliver the remaining 36 filters. Mal has checked the supplier's specs, and he thinks it should be OK. We should place one order for 40 units, and ask Quinstar to deliver the first 4 units for our testing. If they fail to meet with the specs, then the order would be automatically canceled. 8. Regarding the InP MMIC, Mal says that the test result for the K-band amplifier is pretty close with their prediction. Russell has been fixing up some problems. They have one amplifier completed; they will test it by this week. Mal will tell us about the result by next week. 9. Regarding the Specek's amplifiers, Leo will check with Prof. Chu to find out the latest status. 10. Regarding the NRAO W-band amplifiers, Mintang asked for some mechanical drawing, bias drawings and circuit drawing from NRAO. He received some information from NRAO.	H. Wang M. Sinclair H.Wang H.Wang H. Wang H. Wang M. Sinclair H.C. LU M. Sinclair H.C.Lu M.T. Chen			ongoing late Dec. DONE ongoing early Nov. ASAP ongoing Next week ASAP DONE
Lag Correlator Hybrid
1. Jeff says if we could use the alumina for the transmission line in the correlator, the area required for the whole correlator would be 5 times smaller. Currently some of his students are working on this study and doing some calculation. And it needs a couple of weeks more to know the answer. 2. Regarding the prototype mixer based lag correlator; Jeff inputs some design information by email. You can read it on the AMiBA web page as well. 3. Warwick inputs a test report on the HBT Gilbert Cell multiplier wafer, and the result looks like promising to use that multiplier up to 20GHz bandwidth. 4. Warwick says he did few measurements on the narrow band prototype correlator and it seems going very well and it is working quite nicely at the 3 GHz bandwidth. And the next thing is to do the noise measurement. 5. Paul Shaw is trying to put together a comprehensive cost analysis for the whole project, and we need to have a cost projection for the whole thing including correlator. Warwick says that he has been trying to get a quote from the ACX company in Taiwan on the packaging correlator, and their offer would be the fundamentals to start that cost projection.	J. Peterson J.Peterson W. Wilson W. Wilson W. Wilson			ongoing DONE DONE ongoing ongoing
Receiver
1. Mingtang is working on the Dewar layout; he is waiting for the mount layout, wish to know the supporting interface between receiver and mount. He is still working on the components in the deward. Bob says that he got some drawings from Kingsley, so he will talk with Mingtang after this meeting. 2. Regarding the collaboration proposal on the development of NRAO OMT, Mingtang thinks that is a good idea, but still needs Fred¡¦s approval. Paul asks John to provide cost breakdown and detail time schedule to us accordingly. John agrees to do so; he will work out this information together with J. Kingsley. Concerning the specs and the price, Mal recommends going with the NRAO OMT. 3. Mingtang sent out a linear feed horn design data to Michael and Mal in yesterday. Mal and Michael will look at and comment. Mingtang says that according the prototype dish specification - the F ratio is 4; it would be very difficult for us to design a 14-degree angle feed horn. And this problem should be clarified further with Bob. 4. Jeff says that he has made a design for feed horn year ago, and it is very easy to machine. He will send that design data to Mingtang to look at. 5. Jeff will send the window foam material information to Mingtang once he got it. Mal suggests Mingtang to read the internal report no. 292 of the Electronic Section on the NRAO web site. 6. Mingtang is planning to visit ATNF in early Dec, Michael and Mal say that are fine with them.	M.T.Chen B. Martin J. Payne M.T. Chen C.T. Mingtang J.Peterson J. Peterson M. Sinclair		ongoing ongoing ongoing Ongoing DONE DONE
LO/IF
1.Eugene just generates a NRAO visit report today; he will circulate it to everyone to look at. We will put it on the ASIAA web site, and welcome everyone to take a look and to comment. 2.Eugene is working on ¡§the wideband LO noise effect calculation¡¨; he will send over to everyone to look at once finished.		Y.J. Hwang Y.J. Hwang		DONE DONE
Platform/Mount/Dishes
1.Jeff doesn¡¦t think the caesarian could work with the 30cm antenna due to its high ground pick up. He will do some quantitative analysis to demonstrate this case. 2.Regarding the height of ground shield for our antenna, Bob requests Michael to ask their expert to verify what size is good for us? 3. Prof. Peng of the Tsing Hua University will give us a lunch talk on what he knows and what he think about the hexapod mount by today. 4.Fred says that regarding the three mounts things, it sounds great on the surface, but he is not convince on many grounds, e.g. UV coverage, cost, enclosure, delay lines, etc. We really need to resolve those issues very quickly. 5. Bob is going to visit the firm in Germany "Vertex GmbH" by next week, he will talk with them about the hexapod mount and the conventional mount, to see what they can supply. We are trying to get better specification together before then, more specific requirement we need.		J. Peterson M.Kesteven M.T. Chen		ASAP ongoing DONE
Site acquisition
Bob thinks it is promising to find some site in Hilo.				Ongoing
Prototype Specification and Project Book
Traveling
Bob Nov.13~20 / Jeff ~ Nov.20
Next Meeting
8:30pm EDT, 8:30am Taiwan, 10:30 Australia, 5:30pm Tucson/Thursday/Nov. 16. 2000