Ground Station for Satellite Operation (CySat) May Client: Matthew Nelson Advisor: John Basart Team: Karl Deakyne, SungHo Yoon, Luke Olson Cyclone Satellite (CYSAT)

Project Plan  Overall goal: Ground Station for CySat Team Fick Observatory, Dish Antenna High sensitivity receiving Automatic Tracking  Previous Team: Dish control from computer Build 440 MHz Sub reflector Rotary Encoders for tracking dish position  Our team: Ensure strength and signal to noise ratio of received signal is adequate Tracking

3 Requirements  Functional The system shall be able to receive a signal that is sent from an orbiting satellite with a sent power of 1W (or 3 dBm) and the signal should be easily recognizable by a standard radio located in the observatory The system shall be able to automatically track an orbiting satellite  Non-Functional The system shall fit inside the dish The system shall be weatherproof

Project Plan  Work Breakdown Luke ○ Develop Tracking Software SungHo, Karl ○ Design and Build Front-End

Schedule

Design – Front End  Calculations – Without modification  Analysis: Signal-to-Noise Ratio = dBm – ( dBm) = 8.68 dB (Input power) - (Sensitivity) = 6.99 dBm These numbers do not yet meet the specifications!  Solution: Front-End Box for amplification Received power at the satellite dish (worst case) dBm (by link budget) Coax Cable (Belden 9913 (RG-8), 200ft)-5.8dB/200ft(Insertion Loss) Radio Input Power dBm Power of Radio Sensitivity (Standard Radio)-121.9dBm

7 Design Front-End Progression 3 First Full Parts Design

Design Front-End Progression Design Before Purchasing Parts

9 Band Pass Filter  Problems with BPFs Commercial filters not perfect for our range Custom filter not immediately available  Solutions Considered putting LPF and HPF in series Advised advised to continue without BPFs, but to leave room for eventual installation  Effects Radio filters around center frequency Pre-filtering desirable, but not necessary Slight decrease in SNR, but this is negligible

10 Design Front End Progression 5 Final Design Apr 2010

Design – Tracking Software  Requirement: Automatically track an orbiting satellite Solution: ○ Pull azimuth and elevation from Ham Radio Deluxe ○ Track the position of the dish with existing rotary encoders ○ Move dish through an Ethernet connection with the motor control microcontroller

Design – Tracking Software

Implementation –Tracking Software  Java Based Application GUI ○ Allows user to manually control dish, track a satellite, and set calibration settings Data Monitoring ○ Two Threads DDEThread: Continuously pulls azimuth and elevation from Ham Radio Deluxe, using Dynamic Data Exchange DishPositionThread: Monitors the rotary encoders to track the azimuth and elevation of the dish Calibration ○ Automatic Calibration to ensure accurate tracking

Implementation – Tracking Software

15 Implementation – Front End 6

16 Required Specifications  Filter Design Frequency, 440 MHz Filters out harmonics Low power  Switch Must work at 440 MHz, minimal losses High Power Rating (~10W) Electrically controlled  Radio High Sensitivity Low Cost  Amplifier 440 MHz Low Noise Amplifier Low noise figure (<3) Moderate gain (~20dB)

17 Device Specifications  ZX60-33LN+ (LNA) L ow noise Amplifier Low noise figure = 1.1 Gain = MHz  881-CCR-33S6O (Switch) Loss at 440 MHz <.4 dB Power Rating at 440 MHz = 100W CW Electrically controlled  Filter Too costly to get device within specification  Radio Too costly for budget, the CySat team will have to provide the radio Our Recommendation: Icom 208H Sensitivity =.18 uV, -37dBm Cost = $310

18 Final Parts List 7

Calculations – With Front-End  Analysis: Signal-to-Noise Ratio (at Satellite Dish) = dBm – ( dBm) = dB Power into the Radio > Radio Sensitivity : Radio is able to decode the input signal. (Input power) - (Sensitivity) = 23.0 dBm Power in process (440MHz) Received power at the satellite dish (worst case) dBm (by link budget) System noise power dBm (by Noise Temperature) Coax Cable (Carol® C1166(RG-8), 30ft)-2.76dB/30ft(Insertion Loss) LNA (ZX60-33LN+)21dB(Gain) RF Switch (ZX80-DR230+), 3units-2.1dB(Insertion Loss) SMA to SMA adapter (SM-SM50+), 4units-0.12dB(Insertion Loss) Coax Cable (Belden 9913 (RG-8), 200ft)-5.8dB/200ft(Insertion Loss) Radio Input Power-98.9dBm Power of Radio Sensitivity-121.9dBm

Test Plan  Individual Part Testing  Front-End Testing  Tracking Software prototyping  Overall System Evaluation and Testing

Test  Place: SSCL Lab at Howe Hall  Devices: Signal Generator (Model: ) Spectral Analyzer (Model: ) DC Voltage Generator (Model: )  Methods: RF Switches ○ Apply 440MHz signal to the input of switch, using a signal generator. ○ Change 0 DCV to 12 DCV supplied to switches. ○ Observe if signal path is changed from “Normally Closed” to “Normally Open”. Low Noise Amplifier (LNA) ○ Apply 440MHz signal to LNA. ○ Connect into spectral analyzer ○ Observe if the incoming signal is amplified as we expected. Whole Front-End System ○ Combine two methods above.  Checkpoints: if switches are working properly depending on voltage change. if the amplifier(LNA) is working properly as we expected. RF Switch LNA

Test Results Switch 1 Normally Open (N.O.)Normally Closed (N.C.) FrequencyPowerFrequencyPower 0V AppliedNoise-67dBm440MHz10.06dBm 12V Applied440MHz10.05dBmNoise-66dBm Switch 2 Normally Open (N.O.)Normally Closed (N.C.) FrequencyPowerFrequencyPower 0V AppliedNoise-68dBm440MHz10.04dBm 12V Applied440MHz10.06dBmNoise-67dBm Switch 3 Normally Open (N.O.)Normally Closed (N.C.) FrequencyPowerFrequencyPower 0V AppliedNoise-67dBm440MHz10.06dBm 12V Applied440MHz10.05dBmNoise-66dBm Signal(440MHz): dBm Noise power: -50 ~ -80 dBm  Switch Test (Model: Mouser CCR-33SC-N) Normally OpenNormally Closed Conclusion: Verified its switching operation

Test Results InputOutput Center frequency: 440MHz Magnitude of Signal: -58.6dBm Center frequency: 440MHz Magnitude of signal: -38.1dBm Experimental Gain: 20.5 dB Expected Gain:21.1 dB Conclusion: Similar gain as expected  Low Noise Amplifier (Mini-circuits ZX60-33LN+)

Test Results  Whole Front-End System Testing Frequency: 439.9MHz Signal In: -39.9dBm Signal Out: dBm  Experimental Gain from the system: dB  Expected Gain:16.01 dB  Analysis Better Gain than expected Gain Error reasoning: Gain and loss in parts’ manual are less accurate for 440MHz.  Conclusion: The whole system is working as expected.

Prototyping/Testing – Tracking Software  Ham Radio Deluxe Test

Prototyping/Testing – Tracking Software  Motor Control Test Tested with microcontroller

Evaluation of Overall System  Ideally Install sub reflector Install front-end box Install software Test entire system with orbiting satellites Train CySat on how to use the system But… 27

Evaluation of Overall System  Issues During winter the dish was frozen ○ Unable to do anything until March In March we discovered that the dish does not move up/down Numerous trips to the Fick Observatory to attempt to fix issue failed Rotary Encoders are only partially installed, can’t install them until the dish moves down Can’t install sub reflector or front-end box until dish can be moved down 28

Conclusions  Implemented systems that we designed  Unable to successfully implement final product, due to unforeseen issues at the Fick Observatory  Future work: Fix issues at Fick Observatory ○ Motor Control ○ Rotary Encoders Install Sub-reflector, front-end box

Questions