Ku-Band Receiver System for SHAO

Transcription

1 Ku-Band Receiver System for SHAO Overview Brent Willoughby July 2014 Atacama Large Millimeter/submillimeter Array Expanded Very Large Array Robert C. Byrd Green Bank Telescope Very Long Baseline Array

2 SHAO 65m Ku band system deliverables One complete -style Ku-band receiver One complete Feed matched to 65m optics One additional Ku-band Ortho-Mode Transducer with a rotary flange for testing purposes Upgraded software package One Scott Tee Cryo refrigerator AC supply Spare units of all critical receiver components C band upgrade components 2

3 SHAO Ku Band receiver and Feed Upgraded 5% and 50% CAL design Option for temperature controlled Noise Diodes Scott Tee delivery to enable full Cryo control 3

4 SHAO Ku Block Diagram 4

5 Compliance Matrix: System testing and verification Req. No. Abbreviated Description Compliance Method Additional Notes Compliance 2.1 -equivalent performance By design Receiver and feed match capabilities by utilizing proven design in hardware, software, and firmware as deployed in. Specific performance requirements are found below Interoperability By design & inspection Structural interfaces and integration verified via 3D model to the 65m antenna prior to shipment Receiver & feed integrate via C-band M/C and power distribution by virtual of identical design and lab usage Receiver integrates with SHAO IF switching and distribution systems by design. 5

6 2.3 Receiver Bandwidth 2.3 Receiver Bandwidth FAT GHz verified. See SHAO Ku Band 12-18Ghz Receiver System technical manual, section 9. 6

7 2.4.3 Receiver Noise Temperature Receiver Noise Temperature, averaged, at 15 K or lower with SHAO feed SAT, FAT SAT: Verify Trcvr on site at a single frequency within the GHz BW. FAT: In-lab measurements average 8.3 K, See SHAO Ku Band Ghz Receiver System technical manual, section 9.1. FAT SAT TBD 7

8 4.4.6 Cool Down from ambient Cool down from ambient temperature vs. time 15 K and 50 K SAT, FAT 12 hours cool down time. FAT: recorded cool down time <9 hours, as recorded in SHAO Ku Band 12-18Ghz Receiver System technical manual, Figure 5.5 SAT: To be measured at SHAO FAT SAT TBD 8

9 4.6.4 Monitor and Control Monitor and Control function verification SAT,FAT Verified at NRAO through utilization of automated test stands. See SHAO Ku Band 12-18Ghz Receiver System technical manual, section 9 for typical data produced. 9

10 Compliance Matrix: System testing and verification 2.5 RFI By design Hardware design utilizes the receiver design, and no specific RFI immunity is required. 2.6 Safety By design Built-in interlocks are designed into the receiver cryogenic system. 2.7 Maintenance & System Life By design & inspection There are no exposed VDC terminals above +33 Volts or any exposed VAC terminals. See SHAO Ku Band 12-18Ghz Receiver System technical manual, section based design operates in environment similar to SHAO environment. SHAO shall provide a weatherproof and temperature stable environment that is at least 20 C +/- 10 with a relative humidity of 20-80% Verified spare parts kit prior to shipping Recommended maintenance protocols should be followed for commercial Cryogenic components such as the CTI 350 refrigerator. 10

11 Noise Calibration High 50% Tsys High and Low Noise Calibration temperature (K ) FAT The noise calibration signal input is equivalent to ~5% (low noise) or ~50% (high noise) of the nominal Tsys, and is remotely selectable. Tsys is designed to be 27 K, see req , and measurements show appropriate values as recorded in SHAO Ku Band 12-18Ghz Receiver System technical manual, section 9. 11

12 Noise Calibration Low 5% Tsys 12

13 System Gain System Gain (db) FAT The Ku Receiver system Gain shall be nominally 50 db, taken using a 300K input termination and output power measured over the full bandwidth as recorded in SHAO Ku Band manual. NON- WAIVER GRANTED 13

14 Output power Axial ratio Output Power (dbm) FAT Output power shall be -35 dbm/channel nominal over full bandwidth with 77 K cold load over the feed. Averaged value is -32dBm, as shown in SHAO Ku Band 12-18Ghz Receiver System technical manual, section Receiver Axial Ratio (db) FAT <1.5 db with a goal of 1 db. See figure 9.3 in SHAO Ku Band 12-18Ghz Receiver System technical manual. 14

15 , Headroom 1% gain compression Headroom (db) FAT The estimated headroom of the Ku band receiver is greater than 28 db. Headroom is defined as the ratio of 1% compressed output power to the receiver output on cold sky (Tsys 27K) 15

16 Total power (ASD) Total Power Stability (ASD) FAT As measured in the laboratory test, provided as characterization of receiver. 16

17 Calibration modes Calibration Modes Features & Interfaces By design Requirements cover the various features and interfaces provided by an style receiver. 17

18 Compliance Matrix: System testing and verification RCP & LCP RF output connector type By design Connector shall be SMA-F RCP and LCP highattenuation outputs By design, FAT RCP and LCP high-attenuation outputs provided from a coupler before the LNAs. Signal provided at -30dB. Connectors for this output shall also be SMA-F. Measured at -34dB NON- WAIVER GRANTED 18

19 DC Voltage tolerance Nominal receiver DC regulated voltage outputs: +/-15 VDC, +/- 5VDC, +28 VDC FAT +/- 5% tolerance Nominal values shown in SHAO Ku Band 12-18Ghz Receiver System technical manual, section

20 Nominal Receiver current Nominal Current for each regulated supply voltage FAT As measured in the laboratory test. Nominal values shown in SHAO Ku Band 12-18Ghz Receiver System technical manual, section TBD by NRAO 20

21 Compliance Matrix: System Testing and verification Receiver input voltage SAT -48VDC 10 Amperes shall be provided by SHAO TBD by SHAO Scott Tee AC input voltage SAT 220 Vac 50Hz shall be provided by SHAO TBD by SHAO Scott Tee AC output voltage By design 150 VAC dual phase to refrigerator, 120 VAC single phase for solenoid and heater 21

22 Compliance Matrix: System testing and verification Cool down from ambient plot of 15K and 50K temperature vs. time FAT 12 hours cool down time. Recorded cool down time <9 hours, as recorded in SHAO Ku Band 12-18Ghz Receiver System technical manual, Figure Dewar Leak Rate FAT 7.5*10-6 cm 3 /s He as measured by NRAO Overall leak rate measured at 3.8*10-6 cm 3/s He Cryogenic Design by NRAO By design The Ku-band receiver system will use a Model CTI 350 Refrigerator. The Ku-band receiver shall be cryogenically cooled using a closed-cycle refrigeration system, based on a 2-stage Gifford-McMahon refrigerator, with pressurized ultra-high purity helium gas as the refrigerant Cryogenic Hardware from SHAO SAT The 1st stage at 50 K shall provide cooling for the thermal radiation shield, and the 2nd stage at 15 K shall be used for cooling the LNAs and OMT assembly. SHAO will provide all components of the helium refrigerant system to operate the CTI 350. The He supply pressure shall nominally be 280 ±20PSI. The He return pressure shall nominally be 80 ±20PSI. TBD by SHAO 22

23 Compliance Matrix: System testing and verification Vacuum Design by NRAO By design The pressure in the manifold and Dewar assembly shall be monitored by individual thermocouple-type vacuum sensors provided by NRAO. A 0.75 in. (19mm) ID vacuum hose shall be used to connect the vacuum pump to the receiver vacuum manifold. The electronics within the receiver assembly/card cage shall perform the proper sequencing of pump, solenoid, heater, and refrigerator control, to allow automatic cooldown or warm-up via a single command, under direct manual or remote control. NRAO will provide a pump request electronic module which can interface to the SHAO-selected vacuum pump. The Scott Tee module will also provide the required 120 VAC for control powering the solenoid vacuum valve. The electronics within the receiver assembly/card cage will control the pump request module Vacuum Hardware from SHAO SAT SHAO will provide a vacuum pump with a blank-off pressure of < 10µm Hg, (0.0133mbar). SHAO will provide the vacuum lines up to the receiver vacuum manifold input. TBD by SHAO 23

24 Compliance Matrix: System Testing and verification PC-based laboratory program update By design Program shall be updated form C-band deliverable to include Ku-band system M&C system hardware By design The analog and digital I/O M&C system shall have a 50-pin D-sub interface connector. The Ku-band system shall include the card cage Complete set of monitor data collected at final receiver/feed test SAT As provided and shown during installation card cage design By design The card cage shall contain an LNA bias card ( ) and control card ( ) with capabilities as described in Systems Requirements document Diode protection card By design A diode protection card shall be used on the Ku-band receiver. This card is mounted inside the dewar directly to the 32-pin hermetic feed-thru connector. The diode protection card protects the LNAs from over-voltage conditions and transient spikes. It also contains an EPROM from which the M/C system can obtain the receiver s ID information (i.e., frequency band, serial number and revision number). TBD 24

25 Questions/comments? 25