Ground Station for Satellite Operation (CySat)

1
Ground Stationfor Satellite Operation(CySat)

• May 10-07
• Client Matthew Nelson
• Advisor John Basart
• Team Karl Deakyne, SungHo Yoon, Luke Olson

Cyclone Satellite (CYSAT)
2
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

4
Project Plan

• Work Breakdown
• Luke
• Develop Tracking Software
• SungHo, Karl
• Design and Build Front-End

5
Schedule
6
Design Front End

• Calculations Without modification
• Analysis
• Signal-to-Noise Ratio -109.11dBm
  (-126.27dBm) 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) -109.11 dBm  (by link budget)
Coax Cable (Belden 9913 (RG-8), 200ft) -5.8 dB/200ft (Insertion Loss)
Radio Input Power -114.91 dBm  
Power of Radio Sensitivity (Standard Radio) -121.9 dBm  
7
Design Front-End Progression
First Full Parts Design
3
8
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
Final Design Apr 2010
5
11
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

12
Design Tracking Software
13
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

14
Implementation Tracking Software
15
Implementation Front End
6
16
Required Specifications

• Switch
• Must work at 440 MHz, minimal losses
• High Power Rating (10W)
• Electrically controlled

• Amplifier
• 440 MHz Low Noise Amplifier
• Low noise figure (lt3)
• Moderate gain (20dB)

• Filter
• Design Frequency, 440 MHz
• Filters out harmonics
• Low power

• Radio
• High Sensitivity
• Low Cost

17
Device Specifications

• 881-CCR-33S6O (Switch)
• Loss at 440 MHz lt .4 dB
• Power Rating at 440 MHz 100W CW
• Electrically controlled

• ZX60-33LN (LNA)
• Low noise Amplifier
• Low noise figure 1.1
• Gain 21.3 dB _at_ 440MHz

• 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
19
Calculations With Front-End
Power in process (440MHz) Power in process (440MHz) Power in process (440MHz) Power in process (440MHz)
Received power at the satellite dish (worst case) -109.11 dBm  (by link budget)
System noise power -126.27 dBm (by Noise Temperature)
Coax Cable (Carol C1166(RG-8), 30ft) -2.76 dB/30ft (Insertion Loss)
LNA (ZX60-33LN) 21 dB (Gain)
RF Switch (ZX80-DR230), 3units -2.1 dB (Insertion Loss)
SMA to SMA adapter (SM-SM50), 4units -0.12 dB (Insertion Loss)
Coax Cable (Belden 9913 (RG-8), 200ft) -5.8 dB/200ft (Insertion Loss)
Radio Input Power -98.9 dBm  
Power of Radio Sensitivity -121.9 dBm  

• Analysis
• Signal-to-Noise Ratio (at Satellite Dish)
  -109.11dBm (-126.27dBm) 17.16 dB
• Power into the Radio gt Radio Sensitivity
• Radio is able to decode the input signal.
• (Input power) - (Sensitivity) 23.0 dBm

20
Test Plan

• Individual Part Testing
• Front-End Testing
• Tracking Software prototyping
• Overall System Evaluation and Testing

21
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

RF Switch
LNA
22
Test Results

• Switch Test (Model Mouser CCR-33SC-N)

• Signal(440MHz) 10.26 dBm
• Noise power -50 -80 dBm

Switch 1
  Normally Open (N.O.) Normally Open (N.O.) Normally Closed (N.C.) Normally Closed (N.C.)
  Frequency Power Frequency Power
0V Applied Noise -67dBm 440MHz 10.06dBm
   
12V Applied 440MHz 10.05dBm Noise -66dBm
Switch 2
  Normally Open (N.O.) Normally Open (N.O.) Normally Closed (N.C.) Normally Closed (N.C.)
  Frequency Power Frequency Power
0V Applied Noise -68dBm 440MHz 10.04dBm
   
12V Applied 440MHz 10.06dBm Noise -67dBm
Switch 3
  Normally Open (N.O.) Normally Open (N.O.) Normally Closed (N.C.) Normally Closed (N.C.)
  Frequency Power Frequency Power
0V Applied Noise -67dBm 440MHz 10.06dBm
   
12V Applied 440MHz 10.05dBm Noise -66dBm
Normally Open
Normally Closed

• Conclusion Verified its switching operation

23
Test Results

• Low Noise Amplifier (Mini-circuits ZX60-33LN)

Input
Output
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

24
Test Results

• Whole Front-End System
• Testing Frequency 439.9MHz
• Signal In -39.9dBm
• Signal Out -21.43dBm
• Experimental Gain from the system 18.47 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.

25
Prototyping/Testing Tracking Software

• Ham Radio Deluxe Test

26
Prototyping/Testing Tracking Software

• Motor Control Test
• Tested with microcontroller

27
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

28
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,
  cant install them until the dish moves down
• Cant install sub reflector or front-end box
  until dish can be moved down

29
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

30
Questions