PWI: Plasma Wave Instrument

1. PWI: Plasma Wave Instrument

2. Update of the PWI status (after the previous SWG) Past major events: October 13: PWI 6th Kyoto meeting（Kyoto Univ.) Discussion of the electrical interface and EMC October 18: EMC board meeting (ISAS) November 21:EGSE Meeting（Meudon） PWI Common GSE December 6: EMC tests of TWTA (Kanazawa)

3. EWO • BBM Development & Tests: • DC CAL/BIAS、Loop gain control • LPF of WFC/OFA/EFD-E & B AM2P • Power supply : • Voltage conversion- Usage of -12V ->-5V • -> increase of power consumption • Under the discussion of the size and weight • considering the additional functions • (To be discussed this week in Kanazawa)

4. SC-LF/SC-DB

5. MEFISTOupdate 22 March 2006 • Max. amplitude (LF) 500 mV/m • Bit resolution 0.015 mV/m • Spacecraft potential -100 to +100 V • Frequency range DC – 3 MHz Sensor wire, 0.1-0.3 mm 1-2 m 13-14 m TiAlN probe 40 mm diameter “puck” Boom, connected to s/c ground

6. Second-Surface Mirror Development Work is on-going to develop an SSM, mainly for the boom wire. Goal is to achieve: • Mechanical flexibility • Electrical conductivity, to keep all satellite surface potentials within ~1V • Temperature below 150°C to avoid damage to wire insulator material

7. Thermal Modelling • Thermal model of MEFISTO “stand-alone” has been developed and run • All temperatures within acceptable limits for all mission phases • Model has been supplied to JAXA, for integration with spacecraft level model • Currently model details are being discussed and iterated with JAXA thermal engineers

8. Electronics • Design and development of flight electronics is proceeding as planned • Co-ordinated EGSE development in Europe is progressing Mechanics • Design and development of flight machannics is proceeding as planned

9. Funding status • Swedish National Space Board • Royal Institute of Technology • Swedish Institute of Space Physics have signed funding commitments

10. Requests (reminder) • Normal sun angle > 92 deg, i.e., 93 +/- 1 deg, if possible • Maximum potential difference on external surfaces of order 1 V, i.e., all external surfaces must be (reasonably) conductive

11. SORBET instrument bloc diagram

12. New ASIC design (January 2006) • Analogue functions on a single chip : • Specific design (Full Custom) • Thin CMOS technology (AMS 0.35um) • 2 logarithmic amplifiers (AGC) • 2 low noise mixers • 1 selective band-pass filter • 1 low noise operational amplifier • Functional testing showed : • Good performances • Improvement of the dynamic range • Less power needed • Future actions • Thermal testing (soon) • Radiation evaluation (2Q/2006) • Decision to continue the ASIC solution (3Q/2006) 2.6mm 2.6mm

13. Major Events in the future March, 2006: PWI local meeting in Kanazawa March 2006: EMC tests of the MSASI motor

14. PWI 前回設計会議からの進捗状況 今後の予定 ●エレキ EWO-EFD: 回路設計 DC CAL/BIAS、Loop gain control EWO-WFC/OFA: 回路設計 センサとのインタフェース、AC CAL レベルダイアグラム SORBET: EWOとのインタフェース AM2P: LVDS: +20g、電力3倍？ MEFISTOレングスモニタ検討中 CMD&STATUS CAL信号 → EWOへ 観測シーケンス検討 BBM製作・特性試験（富山県大） （BIAS/CAL、LGC、FPGA） フィルタBBM製作（MHI） 　　　　　　　　特性試験（京大）

15. PWI 前回設計会議からの進捗状況 今後の予定 ●その他 Software / operation: データ取得シーケンス検討（金沢大） 各センサ／受信機 ⇔ MDP EMC: MMO EMC Meeting（10/18:ISAS） → EMC ver.1.11 TWTA EMC試験（12/6：金沢大） RE-02 / RE-04（電界 / 磁界） CDC（電流） MDP-2内接地方式： 1点接地を基本 アナログ観測信号は差動受渡 cf. multiple ground: for clean E single ground: for clean B 基本案確定（3月：PWI+MDP） MSASIモータEMC試験（3月：金沢大） 具体的議論（3月）