Avionics Group Project

Chris Flood Matt MarcusKiran PatelTim Russell

Problem Statement

• Calculate communications link budgets for a variety of links

• Compile sensors list for mission• Develop list of possible ENAE484 projects for

next semester and rank top 3 project ideas

Sensors List

• Proximity Sensors• Linear Motion • Angular Rotation• Hull Temperature• Cabin Temperature• O2 / CO2 / CO / Humidity Sensors• Cabin Pressure• Solar Panel Energy Output• Fuel Gauge

Proximity Sensors

• High criticality sensors, will have redundant sensors in case of failure during mission

• Must function for proper navigation• Sampling rate - 1Hz• Scanning Laser Rangefinder– 10 total sensors• 4 spaced 90 degrees apart all the way around the craft• 4 sensors redundant to these on vehicle hull• 2 placed on bottom of craft for docking and landing

Translational and Angular Motion

• Continuous high sampling rate• Extremely critical system for navigation and control• Have redundant sensor in case of failure• Sampling Rate - 10 Hz – Important to have up to date information for spacecraft

motion and control • Use stock 2 IMUs– Measure x, y, z, roll, pitch, yaw– ENERGY REQUIREMENTS

Cabin Temperature / Pressure Sensors

• Highly critical sensors for life support applications• Not necessary for spacecraft function• Sampling Rate - 1Hz• Absolute Pressure Sensor for pressure• Thermistors for Cabin Temperature• Determine cabin pressure throughout mission• Keep cabin pressure within habitable limits• Keep cabin temperatures within habitable limits

O2 Sensors

• For O2 tanks, important for tracking propellant pressures – absolute pressure for tanks

• Sampling Rate – 1Hz• Detect O2 levels within cabin at any point in time• Determine limits for safe operation, remain out of

critical flammability limits• O2 pressure sensors for O2 tanks• Determine pressure, amount of usable O2

remaining in tanks at any given time during mission

CO2/CO Sensors

• Not critical for mission, only determines CO2/CO in cabin, mission continues with or without

• Sampling Rate – 1 Hz• Determine levels of CO2/CO within crew cabin• Remain within safe limits for astronaut habitability• Determine amount of CO2/CO scrubbing necessary

at any point in time during mission• ENERGY REQUIREMENTS

Solar Power Energy Output

• Use voltmeters to determine voltage generated from solar cells

• Sampling rate: 10Hz• Determine power output of solar panels over

time• Ensure adequate storage and generation of

energy• Disable non vital systems during power lows

Fuel Gauge

• Keep track of pressures and amounts of propellants remaining for mission

• Ensures proper rationing of propellants for use throughout mission duration

• Sampling rate: 10Hz • Very high criticality for propulsion system

DBTE Ideas : Human Factors for an Inflatable Habitat (Top 3)

• Optimal interior layout / sizing• Launch configuration for uninflated structure• What can we test?– Configuration and placement of hardware– Create various different layouts for habitat and have

participants rate ease of task completion each configuration

DBTE Ideas : Window configuration (Top 3)

• Determine adequate sightlines for landing• What can we test?– Test different window configurations / layouts– Design a variety of window configurations and find

optimal window angle and layout for maximum visibility

DBTE Ideas : Window configuration (Top 3)

• Why do we care?– Previous Space habitats (e.g. ISS) have not been inflatable– Gather data on efficient layout and design of inflatable

habitat

DBTE Ideas : Window configuration (Top 3)

• Why do we care?– Landing is riskiest part of mission, human

executed task, ensure proper visibility

DBTE Ideas : Sleeping Arrangements (Top 3)

• Create adequately comfortable sleeping conditions for astronauts

• What can we test?– Bed types and arrangements within crew cabin– Test sleep quality through various sleeping

configurations via stamina and functionality test after sleeping

• Why do we care?– Sleep is critical for astronaut health and for proper

functioning during mission

Additional DBTE Ideas

• Water cycle taste test• Airlock evaluation• Situational awareness of robotics operator• Ladder design• Visibility when docking• Suit port entry exit

Communication Link Budgets

• We will use White Sands receiving antenna (WS-1) on Earth– 18m diameter antenna

• L-2 relay satellite modeled as TDRS• Capsule high gain antenna will be outfitted for

Ku, Ka, and S band transmitters– 0.5m diameter parabolic dish– 60.5 W max power consumption

Link Budget: Ku Band Directly to EarthdB

Speed of light m/sec c 3.00E+08 84.77Frequency Hz f 1.20E+10 100.79Wavelength m l 0.0250 -16.02Diameter of Transmitting Antenna m d(t) 0.50 -3.01Area of Transmitting Antenna m^2 A(t) 0.20 -7.07Efficiency of Transmitting Antenna h(t) 0.55 -2.60Transmitter Gain G(t) 2.17E+03 33.37Transmitter Power W P 15.00 11.76EIRP W EIRP 3.26E+04 45.13slant range m D 4.06E+08 86.08Power flux density W/m^2 F 1.58E-14 -138.02Diameter of Receiving Antenna m d(r ) 18.00 12.55Area of Receiving Antenna m^2 A(r ) 254.47 24.06Efficiency of Receiving Antenna h(r ) 0.55 -2.60Receiver Gain G(r ) 2.81E+06 64.49Carrier Power Received W C 2.21E-12 -116.56Receiver System Noise Temp degK T(s) 300.00 24.77Boltzmann Constant J/degK k 1.38E-23 -228.60Noise Spectral Density J/degK N(o) 4.14E-21 -203.83Figure of Merit Gr/Ts Gr/Ts 9.38E+03 39.72Free Space Loss L(fs) 4.15E+22 226.19Total System Loss L(ts) 2.75 4.40Receiver C/No Available Hz C/No(rcv) 1.93E+08 82.87Bit Error Rate BER 1.00E-05 -50.00C/No Required Hz C/No(req) 9.40E+07 79.73Data Rate bits/sec R(b) 1.00E+07 70.00Eb/No Received Eb/No(rcv) 19.35 12.87Eb/No Required Eb/No(req) 9.40 9.73Link Margin 2.05839 3.14

Link Budget: S-Band Directly to EarthdB

Speed of light m/sec c 3.00E+08 84.77Frequency Hz f 2.50E+09 93.98Wavelength m l 0.1200 -9.21Diameter of Transmitting Antenna m d(t) 0.50 -3.01Area of Transmitting Antenna m^2 A(t) 0.20 -7.07

Efficiency of Transmitting Antenna h(t) 0.55 -2.60Transmitter Gain G(t) 9.42E+01 19.74

Transmitter Power W P 5.00 6.99EIRP W EIRP 4.71E+02 26.73slant range m D 4.05E+08 86.07

Power flux density W/m^2 F 2.29E-16 -156.41Diameter of Receiving Antenna m d(r ) 18.00 12.55Area of Receiving Antenna m^2 A(r ) 254.47 24.06

Efficiency of Receiving Antenna h(r ) 0.55 -2.60Receiver Gain G(r ) 1.22E+05 50.87Carrier Power Received W C 3.20E-14 -134.95Receiver System Noise Temp degK T(s) 300.00 24.77

Boltzmann Constant J/degK k 1.38E-23 -228.60Noise Spectral Density J/degK N(o) 4.14E-21 -203.83Figure of Merit Gr/Ts Gr/Ts 4.07E+02 26.10Free Space Loss L(fs) 1.80E+21 212.55Total System Loss L(ts) 2.75 4.40Receiver C/No Available Hz C/No(rcv) 2.81E+06 64.48Bit Error Rate BER 1.00E-05 -50.00

C/No Required Hz C/No(req) 1.88E+06 62.74Data Rate bits/sec R(b) 2.00E+05 53.01Eb/No Received Eb/No(rcv) 14.03 11.47Eb/No Required Eb/No(req) 9.40 9.73Link Margin 1.49268 1.74

Link Budget: Ka-Band to L-2 RelaydB

Speed of light m/sec c 3.00E+08 84.77Frequency Hz f 3.20E+10 105.05Wavelength m l 0.0094 -20.28Diameter of Transmitting Antenna m d(t) 0.50 -3.01Area of Transmitting Antenna m^2 A(t) 0.20 -7.07

Efficiency of Transmitting Antenna h(t) 0.55 -2.60Transmitter Gain G(t) 1.54E+04 41.89

Transmitter Power W P 15.00 11.76EIRP W EIRP 2.32E+05 53.65slant range m D 6.50E+07 78.13

Power flux density W/m^2 F 4.36E-12 -113.60Diameter of Receiving Antenna m d(r ) 4.90 6.90Area of Receiving Antenna m^2 A(r ) 18.86 12.75

Efficiency of Receiving Antenna h(r ) 0.55 -2.60Receiver Gain G(r ) 1.48E+06 61.71Carrier Power Received W C 4.52E-11 -103.44Receiver System Noise Temp degK T(s) 100.00 20.00

Boltzmann Constant J/degK k 1.38E-23 -228.60Noise Spectral Density J/degK N(o) 1.38E-21 -208.60Figure of Merit Gr/Ts Gr/Ts 1.48E+04 41.71Free Space Loss L(fs) 7.59E+21 218.80Total System Loss L(ts) 2.75 4.40Receiver C/No Available Hz C/No(rcv) 1.19E+10 100.76Bit Error Rate BER 1.00E-05 -50.00

C/No Required Hz C/No(req) 9.40E+09 99.73Data Rate bits/sec R(b) 1.00E+09 90.00Eb/No Received Eb/No(rcv) 11.90 10.76Eb/No Required Eb/No(req) 9.40 9.73Link Margin 1.26645 1.03

Link Budget: Ku-Band L-2 Relay to EarthdB

Speed of light m/sec c 3.00E+08 84.77Frequency Hz f 1.20E+10 100.79

Wavelength m l 0.0250 -16.02

Diameter of Transmitting Antenna m d(t) 4.90 6.90

Area of Transmitting Antenna m^2 A(t) 18.86 12.75Efficiency of Transmitting Antenna h(t) 0.55 -2.60Transmitter Gain G(t) 2.09E+05 53.19Transmitter Power W P 15.00 11.76EIRP W EIRP 3.13E+06 64.95slant range m D 4.06E+08 86.08Power flux density W/m^2 F 1.51E-12 -118.20Diameter of Receiving Antenna m d(r ) 18.00 12.55Area of Receiving Antenna m^2 A(r ) 254.47 24.06Efficiency of Receiving Antenna h(r ) 0.55 -2.60Receiver Gain G(r ) 2.81E+06 64.49Carrier Power Received W C 2.12E-10 -96.74Receiver System Noise Temp degK T(s) 100.00 20.00Boltzmann Constant J/degK k 1.38E-23 -228.60Noise Spectral Density J/degK N(o) 1.38E-21 -208.60Figure of Merit Gr/Ts Gr/Ts 2.81E+04 44.49Free Space Loss L(fs) 4.15E+22 226.19Total System Loss L(ts) 2.75 4.40Receiver C/No Available Hz C/No(rcv) 5.57E+10 107.46Bit Error Rate BER 1.00E-05 -50.00C/No Required Hz C/No(req) 2.35E+10 103.71Data Rate bits/sec R(b) 2.50E+09 93.98Eb/No Received Eb/No(rcv) 22.30 13.48Eb/No Required Eb/No(req) 9.40 9.73Link Margin 2.37225 3.75

Link Budget: UHF Omni to EVA suitsdB

Speed of light m/sec c 3.00E+08 84.77Frequency Hz f 9.00E+08 89.54

Wavelength m l 0.3333 -4.77Diameter of Transmitting Antenna m d(t) 0.11 -9.74Area of Transmitting Antenna m^2 A(t) 0.01 -20.53

Efficiency of Transmitting Antenna h(t) 0.63 -2.04Transmitter Gain G(t) 6.25E-01 -2.04Transmitter Power W P 0.50 -3.01EIRP W EIRP 3.13E-01 -5.05slant range m D 2.00E+04 43.01Power flux density W/m^2 F 6.22E-11 -102.06Diameter of Receiving Antenna m d(r ) 0.11 -9.74Area of Receiving Antenna m^2 A(r ) 0.01 -20.53

Efficiency of Receiving Antenna h(r ) 0.63 -2.04Receiver Gain G(r ) 6.25E-01 -2.04Carrier Power Received W C 3.44E-13 -124.64Receiver System Noise Temp degK T(s) 300.00 24.77Boltzmann Constant J/degK k 1.38E-23 -228.60Noise Spectral Density J/degK N(o) 4.14E-21 -203.83Figure of Merit Gr/Ts Gr/Ts 2.08E-03 -26.81Free Space Loss L(fs) 5.68E+11 117.55Total System Loss L(ts) 2.75 4.40Receiver C/No Available Hz C/No(rcv) 3.01E+07 74.79Bit Error Rate BER 1.00E-05 -50.00C/No Required Hz C/No(req) 1.41E+07 71.49Data Rate bits/sec R(b) 1.50E+06 61.76Eb/No Received Eb/No(rcv) 20.09 13.03Eb/No Required Eb/No(req) 9.40 9.73Link Margin 2.13710 3.30

UHF Omni to EVA suits

• Antenna diameter of 11cm easily fits on suits• Transportable power of 0.5w is attainable • Slant range of 20km will more then double

max distance transverse by Apollo• Data Rate of 1.5 Mbps will transmit suit video

and all other communications