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TornadoTrak. Critical Design Review February 28, 2012. Bruce Deakyne Trevor McDonald Adam Prulhiere Luke Tonneman Kody Mallory. Project Overview. Operate at 900 MHz Omni-directional and electronic beam-steering modes Autonomous and manual input beam-steering
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TornadoTrak Critical Design Review February 28, 2012 Bruce Deakyne Trevor McDonald Adam Prulhiere Luke Tonneman Kody Mallory
Project Overview • Operate at 900 MHz • Omni-directional and electronic beam-steering modes • Autonomous and manual input beam-steering • Interface with existing architecture • Fit on roof of chase van
Goals • Primary • Receive desired angle from Mobile Control Station (MCS) and steer relative to van orientation • Secondary • Use signal quality feedback from transceiver to finely adjust angle using control law • Tertiary • Track and maintain communication link with multiple aircraft
PhasedArraySystem PowerSystem Fixture RF Power Lvl (Transceiver) 12 V DC ControllerBlock Ethernet Ground PhasedArrayAntenna Signal (Transceiver) Beam Forming Network (BFN)
Array Design • 8 Element Uniform Circular Array • Half Wavelength Radius • Radiating Element: Monopole • Gain: 10 dBi • Elevation HPBW: 63° • Azimuth HPBW: 40°
FCC Compliance • Effective Isotropic Radiated Power (EIRP) • Max EIRP: 36 dBm • EIRP = TX Power + Antenna Gain – Losses • TX Power ≈ 30 dBm • 21 dBm/Antenna
BeamFormingNetwork (BFN) RXNetwork RX PS Ctrl [x8] Phased Array Antenna 12 V DC TR Switch1 TR Switch2 [x8] Transceiver Ground TXNetwork TX PS Ctrl [x8]
Beam Forming Network Transmit Network Transceiver Antennas Controller Receive Network
Transmit Network • Output FCC restricted • Surface Mount Components +20 dBm +5.9 dBm +20.9 dBm 9 dB Divider +8.3dBm T/R φ K +19.1 dBm -2.4 dB + 15 dB -0.9 dB -10.8 dB
Receive Network • Variable Input • Surface Mount Components +31 dB +7.2 dB T/R φ K Σ T/R -2.4 dB -0.9 dB -0.9 dB
Expected Range • Friis’ Transmission Formula
RF Components • Phase Shifter: JSPHS-1000 • 700-1000 MHz • 0-15V Voltage Controlled • 0-180° Phase Control • 50 Ω
RF Components • T/R Switch: SKY13277-355LF SP3T • 500 MHz – 2.5 GHz • 15 ns switch time • High Isolation • 32 dBm max RF power • 50 Ω • Power Splitter/Combiner: JCPS-8-10 • 5 – 1000 MHz • 9 dB, 0° Splitter • 50 Ω
RF Components • Power Amplifier: HXG-122+ • 500-1200 MHz • High IP3 • Gain: 15 dB typical • 50 Ω • Low Noise Amplifier: PMA-545G3+ Ultra • 700-1000 MHz • High IP3 • Gain: 31 dB typical • Noise Figure: 0.9 dB • 50 Ω
RF Board • 4 Layers • RF Layer • Top layer • RO3006 • εr ≈6.5 • 10 mil • Control/Power Layer • Bottom layer • FR-4 • Shielding • Ground plane layers
Component Selection • Stellaris LM3S6965 • 32 bit 50MHz with Ethernet Stack • SCI/SPI/I2C Interfaces • 3.3v supply • 40 GPIO pins • FT232HL USB Interface • DUAL USB to UART and JTAG • CPLD- • USB JTAG Logic and TR Switch Logic
Component Selection • DAC • AD5582YRVZ-ND • Quad DAC Parallel Interface • Connectors • Ethernet-J3011G21DNL • USB-54819-0519
ControllerBoard 3.3, 5, 15 V DC RF Power (Transceiver) RX PS Control [x8] TX PS Control [x8] Ethernet Controller Board DAC Block Ground
Microcontroller PCB Layout USB /CPLD Ethernet Phase/TR_Ctrl DAC Block Power In
PowerSystem Wall Mounted Power Supply 12 V (MCS) 3.3 V DC 5 V DC 15 V DC 120 V (MCS) Linear Regulator Protection Circuits Ground (MCS) Ground
Power System Overview • Powered by MCS • Wall mounted supply • Linear regulators provides DC voltages • Protection for circuits will be incorporated
Power System • 12 V DC Battery • Wall mounted power supply • Converts 120 V AC to 15 V DC • Linear Regulators • Converts 12 V DC to 3.3 V and 5 V • Snubber circuits and TVS diodes offer protection and reliability
Design Considerations • 5 V linear regulator sources at maximum 3 A • Traces are thicker and wider to handle current • Regulators operate over range of input voltages • Battery voltage will decrease over time • Regulators supply necessary current
Protection Circuits • Snubber Circuits • Regulate ground potential • Zener provides clamping • Ground bounce • PDN droop • TVS Diodes • Can dissipate up to 3 kW • Begins to conduct in less than 1 ps • ESD
Power System Wall Mounted Power Supply (15 V) DACs 120 V AC 12 V DC Bus Linear Regulators (3.3 V and 5 V) Snubber Circuits and TVS Diodes RF components and µC