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Electron Losses and Fields Investigation

Subsystem PDREarth Station

Kyle Colton

Los Angeles, California12 November 2014

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BOARD MEMBERS

Name Organization

Sara Spangelo JPL / UMich

Scott Tripp JPL / UMich

Define subsystem scope and responsibility

Provide feedback on the detailed design of the subsystem, down to the schematic level (where needed)

Unify the subsystem team in their efforts (tie the pieces together)

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OBJECTIVE AND SCOPE OF PDR

Overview Space Segment Subsystem Overview Subsystem Team

Knudsen Details Block Diagram Shed Temperatures Junction Box Antenna Array

Boelter Details Block Diagram Rooftop Room

Operations Operational Concept Schedule Calibration Plan Facilities

Performance Assurance Mechanical Assurance Tracking Assurance Link Assurance Data Volume Assurance Subsystem Tests Contamination Control Safety

Trades and Problems

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TABLE OF CONTENTS

Overview • Space Segment• Subsystem Overview• Subsystem Team

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Perpendicular V-Dipoles UHF downlink VHF uplink

Spinning spacecraft Spin fading

He-100 radio 1 watt RF Power 19k2 baud downlink 9k6 baud uplink

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SPACE SEGMENT

Worst VHF: -7.8 dBi Worst UHF: -7.3 dBi

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SPACE SEGMENT NULLS

Knudsen High gain 4 UHF, 2 VHF Yagis

Boelter Lower Gain 1 UHF, 1 VHF Yagi

Worcester Planned east coast station Geographically Diverse Approximately doubles

data volume 2 UHF yagis, 1 VHF yagi

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SUBSYSTEM OVERVIEW

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SUBSYSTEM TEAM

Knudsen

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KNUDSEN DETAILS

UHF/VHF Antenna 436CP42UG (4x) / 2MCP22 (2x)

UHF/VHF Gain (Est) 23 dBi / 16 dBi

Polarization Circular

Preamplifier P432VDG / LNA 70

Noise Floor Pending TradeGain Pending Trade

Amplifier Mirage B-2518-G

Output Power 160 WRotor AlphaSpid RASVertical Load 250 kgTorque 158 N mBreak Torque 1582 N m

Coax LMR-400 / LMR-900

dB/100m @ 150MHz 5.0 / 2.2

dB/100m @ 450MHz 8.9 / 3.8

Run Length (Est) 10m / 15m

Radio Icom IC-910H

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BLOCK DIAGRAM

5’x4’ footprint Housed on top of pallets

Allows water and airflow Building Power and Network Metallic Paint

Reflects Sunlight Elevator Tower

Provides shade “Attic vent” on roof Holes in floor allow airflow

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SHED

Air drawn through floor holes, exhausted through roof fan

Reflective metallic paint on shed exterior

Temperatures now reflect outside temperature

Next step: stabilization

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SHED TEMPERATURES

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SHED TEMPERATURES

Located Foot of the tower

Contains Port dividers (M2) Ethernet Switch Arduino Mega

(rotor control) PoE Injector Amplifier Power regulator(s)

12v to switch, amplifier 5v to PoE

Note: May use I2C Repeaters instead of μC

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JUNCTION BOX

6 ft spacing between UHF antennas

10 ft spacing between VHF antennas

AlphaSpid RAS rotor

Aluminum mast Fiberglass crossbeams

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ANTENNA ARRAY

6 ft.

6 ft.

10 ft.

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KNUDSEN

Boelter

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BOELTER DETAILSUHF / VHF Gain (est) 12 dBi / 13.3 dBi

Polarization Circular

Preamplifier P432VDG / LNA 70

Noise Floor Pending Trade

Gain Pending Trade

Rotor Yaesu G5500

Vertical Load 200 kg

Torque Az/El 137 kg m / 59 kg m

Break Torque 392 kg m

Coax LMR-400

dB/100m @ 150MHz 5.0

dB/100m @ 450MHz 8.9

Run Length (Est) 20m

Duplexer CF-4160

Insertion Isolation VHF / UHF 0.15/60dB / 0.25/60dB

Radio Yaesu FT-897

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BLOCK DIAGRAM - CURRENT

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BLOCK DIAGRAM - FUTURE

2m Cross-Polarized Yagi 7 elements per plane approx 12.0 dBiC

70cm Cross Polarized Yagi 9 elements per plane approx 13.3 dBiC

Yaesu G5500 rotor

TBD Preamp Trade Pending

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ROOFTOP

20m run of LMR-400

Yeasu FT-897 half-duplex radio Controlled via Hamlib Currently has frequency

drifts due to software control Software Trade

Yaesu G5500 rotor control Sat688 “interpreter” Moving to K3NG arduino

based rotor control Gives absolute positioning Allows for more control Gives better feedback

Gpredict tracking software Trade in progress Testing Cal Poly’s Earth

Station Network code

TNC trade Moving from soundmodem

to Kantronics KPC-9612+

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ROOM

Operations • Operational Concept• Schedule• Ground Support Equipment• Calibration Plan

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Command Uplink1. Daily TLEs are fetched from

MOC2. Commands sent from MOC3. Commands loaded into ESN

buffer4. During a pass, commands

are Tx’d5. ESN checks for ACK / NAK6. ESN proceeds on in

commands when possible7. All commands are saved

along with their ACK / NAK and TLEs used for tracking

8. ACK / NAK and TLEs are relayed back to MOC

Data Downlink1. Daily TLEs are fetched from

MOC2. Rotors track during a pass3. LHCP / RHCP RSSI test4. CRC / FEC checked as

necessary (see trade)5. Downlinked packets are

backed up and relayed to MOC (along with TLE record)

6. Basic actions on downlinkedpackets Queue failed packets for

subsequent download request Alert cognizant engineer(s)

about out of bounds engineering data

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OPERATIONAL CONCEPT

Boelter Repair (by Dec 2014) Enhancements (by Feb 2015) Rx Testing (by Mar 2015) Tx Testing (by Jun 2015)

Knudsen Repair (by Jan 2014) Build (by Jun 2015) Enhancement (by Aug 2015) Rx Testing (by Sept 2015) Tx Testing (by Dec 2015)

System Automation Emissions Testing Worcester Station (Pending)

All projects are tested on Boelter first More student accessible Less risk of damage

Knudsen lags behind Boelterin sub-projects, but not overall

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SCHEDULE

Scissor Lift Rental Array alignment

Field strength meter Emissions testing

Array Alignment Install and calibrate

LSM303s when aligned Track reported position Realign if LSMs report

out-of-bounds alignment

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CALIBRATION PLAN

Performance Assurance• Mechanical• Tracking• Link Budget• Data Volume Budget• Testing• Contamination Control• Safety

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Full motion checks before automation to look for snagging

Regular visual inspection Roof mounted cameras watch

antennas LSM303 array checks for

alignment error

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MECHANICAL ASSURANCE

Backup copy of TLEs Save a copy of each TLE used

for pass planning and tracking

Backup downlinked data locally

Queue uplinked data locally before a pass

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TRACKING ASSURANCE

W3GEY’s Link Budget 25.7dB up, 7.6dB down 800km circular, 10° mask 5w Earth, 1w Space 19k2 dn, 9k6 up FSK

Terrestrial Packet Testing On-Orbit spacecraft

CSSWE, Vermont Lunar, CubeBug-2

HAB test

Link Budget Assumes worst case

spacecraft orientation Includes:

Antenna gain Pointing Losses Atmospheric Losses Polarization Losses Line Losses Free Space

Calculations Modulation Scheme

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LINK ASSURANCE

Ground Station:

Ground Station Transmitter Power Output: 5.0watts

Ground Stn. Total Transmission Line Losses: 3.2dB

Antenna Gain: 17.5dBi

Ground Station EIRP: 21.3dBW

Uplink Path:

Ground Station Antenna Pointing Loss: 0.4dB

Gnd-to-S/C Antenna Polarization Losses: 3.0dB

Path Loss: 143.1dB

Atmospheric Losses: 1.1dB

Ionospheric Losses: 0.7dB

Rain Losses: 0.0dB

Isotropic Signal Level at Spacecraft: -127.1dBW

Spacecraft (Eb/No Method):

Spacecraft Antenna Pointing Loss: 6.6dB

Spacecraft Antenna Gain: 3.1dBi

Spacecraft Total Transmission Line Losses: 0.1dB

Spacecraft Effective Noise Temperature: 153K

Spacecraft Figure of Merrit (G/T): -18.9dB/K

S/C Signal-to-Noise Power Density (S/No): 76.0 dBHz

System Desired Data Rate: 9600 bps

Command System Eb/No: 36.2 dB

Demodulation Method Seleted: Coherent FSK

Forward Error Correction Coding Used: None

System Allowed or Specified Bit-Error-Rate: 1.0E-04

Demodulator Implementation Loss: 0.0 dB

Telemetry System Required Eb/No: 10.5 dB

Eb/No Threshold: 10.5 dB

System Link Margin: 25.7 dB

Spacecraft:

Spacecraft Transmitter Power Output: 1.0watts

Spacecraft Total Transmission Line Losses: 0.4dB

Spacecraft Antenna Gain: 1.5dBi

Spacecraft EIRP: 1.1dBW

Downlink Path:

Spacecraft Antenna Pointing Loss: 8.1dB

S/C-to-Ground Antenna Polarization Loss: 3.0dB

Path Loss: 152.7dB

Atmospheric Loss: 1.1dB

Ionospheric Loss: 0.4dB

Rain Loss: 0.0dB

Isotropic Signal Level at Ground Station: -164.2dBW

Ground Station (EbNo Method):

Ground Station Antenna Pointing Loss: 2.7dB

Ground Station Antenna Gain: 24.0dBi

Ground Station Total Transmission Line Losses: 1.4dB

Ground Station Effective Noise Temperature: 213K

Ground Station Figure of Merrit (G/T): -0.7dB/K

G.S. Signal-to-Noise Power Density (S/No): 61.0 dBHz

System Desired Data Rate: 19200 bps

Telemetry System Eb/No for the Downlink: 18.1 dB

Demodulation Method Seleted: Coherent FSK

Forward Error Correction Coding Used: None

System Allowed or Specified Bit-Error-Rate: 1.0E-04

Demodulator Implementation Loss: 0 dB

Telemetry System Required Eb/No: 10.5 dB

Eb/No Threshold: 10.5 dB

System Link Margin: 7.6 dB

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LINK BUDGET

Data Volume Budget Ensure maximum contact

time Calculations done

assuming 10 degree mask Mask can be overcome to

horizon per link budget (1.5w RF)

2 geographically diverse stations (backup telecommand) Increases data down East / West coast ensures

non-overlap in orbit Beginning Error Correction

trade

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DATA VOLUME ASSURANCE

Current Satellite Tracking ISS CSSWE Vermont Lunar CubeBUG-2 BugSat 1 Looking for 19k2

Firebirds 3/4?

Planned High Altitude Balloon Using He-100 radio Allows rotation in free

space at range

Station to station testing On campus or community Terrestrial packet is the

simplest, most configurable test

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SUBSYSTEM TESTS

Lines (network, power) are run through garden hose Protects against water and

UV Drip loops are also used

Shed is elevated from the roof by plastic pallets Allows water to flow under

Possible filter on air holes in shed

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CONTAMINATION CONTROL

Tower Climbing Staff Supervised Gear (harness, hardhat,

etc)

Tower Motion Trip Hazards RF Exposure

Controlled Environment Signage

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SAFETY

Trades and Problems• Preamp Trade• Software Trade• TNC Trade• Problem Areas

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SSB LNA 70 Selected Vital figures

are better Everything

else is acceptable

Note: Cal Poly moving from SSB to AR2

Preamps fried

Support was hard to get

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TRADES - PREAMP

AR2

P432VDG

SSBLNA 435 MKII(Discontinued)

SSBLNA 70

420-450 MHz 430-440 MHz 430-440 MHz

.5 dB Noise .25 dB Noise @ 20C

.35 dB Noise @ 20C

18 dB Gain 22 dB Gain 21 dB Gain

2 oz = 57 g 150 g 140 g

$90 Discontinued $230

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TRADES - SOFTWARE

Nova(NLSA) SatPC32

Pros• Popular• Existing• Low Schedule Cost

• Popular• Existing• Low Schedule Cost

Cons

• Windows only• Current problems with Space-Track• Some implementation time

• Windows only• Some implementation time• Non-free• Closed Source

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TRADES - SOFTWARECal Poly

Earth Station Network

Gpredict Custom Solution

Pros

• Open Source• Network (group)• Community goodwill• Cross Platform• We already need ‘network’ from UCLA to WPI

• Open Source• Least schedule cost

• Our Source• Exactly what we want• Best integration with MOC and other software• Could be cross platform

Cons• Not our policyserver• Some schedule cost

• No native multi-satellite tracking• Linux only

• Highest schedule cost• Highest risk of failure

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TRADES - TNC

MixW Direwolf

Pros • Free software• Uses soundcard

• Open Source• Free software• Uses soundcard

Cons

• Complicated• Platform dependent• Windows only• Closed Source

• Can’t do 19k2

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TRADES - TNC

USRP 2 Kantronics Soundmodem

Pros

• Programmable• “Waterfall”• Best for early orbit• Widest Bandwidth• Save and replay passes

• Established community• Proven to work• Platform independent

• Open Source• Free software• Uses soundcard

Cons • Highest Cost• Least experience

• Closed Source• 90s Tech• “Isn’t there something better?”• Difficult to implement FEC

• Old development• Limited support• Complicated• Platform dependent• Difficult to implement FEC

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PROBLEM AREAS

Problem Status Fix

Schedule Slipping Grow subteam, optimizetime on rooftop

Alignment PlannedRental of scissor lifts, realignment, LSM303s for tracking alignment

Tracking Software In ProgressTesting Cal Poly’s Earth

Station Network software

Corrosion In Progress

Replacing parts as they are needed, working to

weatherize as we upgrade

Thank you to all of our sponsors, stakeholders,and contributors

Shaun Murphy @ Northrop GrummanKatharine Gamble @ UT Austin

Jim White WD0E @ Colorado Satellite ServicesMark Spencer WA8SME @ ARRL

Tony Monteiro AA2TX & Bob Davis KF4KSS @ AMSAT-NA

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ACKNOWLEDGEMENTS

Competition Sensitive. Do Not Distribute.