AMiBA Engineering Telecon Minutes

8, August, 2002

Action items:

1.          Bob/Philippe/           to complete the bidding package for platform

2.          C.J.Ma/K.Y. Lin        to generate a plan of coupling test for prototype and circulate around

3.          Bob/                           to generate a detail test plan on site for prototype including task force & schedule

4.          Bob/Philippe/Ted/    to disassemble the test mount of flawed in design and get modification done it at work shop in Hilo ASAP. Ted should talk to Philippe to sort out how much the counterweight should be added to the mount, and where is the location to put receiver, correlator, IF and LO on the mount to make sure the mount can be operated freely.

5.          Bob/                            to review the new quote of 60cm dish from Dr. Ong and get back to PaulS ASAP.

6.          Mingtang/                   to summarize the stability test result of prototype and circulate around ASAP, Aug 15 is still the target to ship prototype to Hilo.

7.          Huei/                          talk to Todd Gaier to sort out the condition of on wafer test service at JPL. TRW may charge us $5000/circuit for that test.  TRW will finish the first wafer run by end Oct.

8.          C.J. Ma/                        T1network on site has been hooked up, C.J. will check the linkage and interface with IAA net work.

Summary

Correlator:

1.      Derek has passed lots of information about mechanical layouts and component outlines C.T. C.T. has forwarded them to Wing (the mechanical engineer). C.T. and Derek are still need to figure out roughly where and how each component is placed for 3 sections. Ideas for 1st section is pretty much settled. After all sections is settled, Wing can generate a more realistic quote on mechanical design and drawing.

2.      C.T. has run a full set of S-parameter tests on the PV-18 devices and circulate its test result around. For details, please read on web site.

3.      Milton and Yi-Kuei Wu had finished the simulation and output layouts for custom power divider and correlator board. We will transform the layout from AutoCAD format (.DXF) into Protel format (.PCB?) that PCB processing company can access. We will design housings and buy some 3.5mm connectors that can function above 20 GHz for testing these circuits once they're done. For details, please take a look at web site.

4.      Warwick has written a C program to apply the transformation matrix taken from correlator 1 on correlator 1's fringe data. The outcome is not complete as what we expected. C.T. will follow up on checking the matrices and how they work with Warwick's program.

5.      Derek and Warwick discussed each item of the specification last week after the meeting. Final version of the specification is “080102A”. Spec and formal request for quote was sent on 8/2/02 to Marki Microwave, Meridian Microwave, Miteq, and TRW. Changes to spec include:

1.4 VSWR </= 2.0:1 (changed from 1.5:1). We believe 2.0:1 will be OK as long as most of the 2 to 18 GHz band resides closer to 1.5:1, and only occasionally peaks to near 2.0:1. This assumes that the VSWR of C.T.’s custom power divider will be fairly well behaved at around 1.5:1. If need be, we can go back and add 3 dB pads to the output of C.T.s power divider.

1.5 IF Output Connector = 4 female socket contacts, ground connection established through the module case. I asked Jeff Rapadas to increase the size of the socket and to put a Teflon insulator between the socket and the module housing so that we could not bend the socket over. I also asked him to use a filtered feed-through for the mixer output interface. He agreed to do both of these. Jeff agreed to do both of these as per our telecon on 8/6/02.

2.1 Module Responsivity >/= 80 Vrms/W (changed from 100 to accommodate 4 dB loss of PDs).

2.6 Squared Term Contribution </= 5% (changed from 1% based on our measured data).

2.7 Output Impedance </= 100 kOhms (changed from 150 kOhms).  We should easily be able to meet this at our module drive level of -10 dBm.

MMIC:

Prof. Wang and his students generated a series of design report, namely - multiplier & mixer(Gilbert cell based)/M.D. Tseng

http://www.asiaa.sinica.edu.tw/amiba/New/correlator/image/Multiplier%20&%20Mixer_0730.pdf

- wideband amplifier/C.S.Llin

http://www.asiaa.sinica.edu.tw/amiba/New/correlator/image/AMiBA_Wideband_Amplifier_2002_07_31.pdf

- 2-24GHz broadband power amplifier in WIN 0.15 um power HEMT

http://www.asiaa.sinica.edu.tw/amiba/New/correlator/image/TWA009.pdf

Next telecon: Thursday, Aug. 15, at 8:30AM Taipei time.