“THE LOCATOR” R. F. LOCATION SYSTEM MIKE GOULD KARA MCMILLIN MARCUS PEARLMAN CHRIS SINKEY JACOB WILTGEN TEAM ZISSOU presents….
Mar 29, 2015
“THE LOCATOR”R. F. LOCATION SYSTEM
MIKE GOULD KARA MCMILLIN MARCUS
PEARLMAN CHRIS SINKEY JACOB WILTGEN
TEAM ZISSOU presents….
Power
Rectifier
Amplifier
68HC11
Microcontroller
USB Interface
Receiving Antennas
TransmittingAntenna
R.F. Location Project Compass Design
• Transmitting Antenna sends power signals
• Antenna arrays receive power signal
• Power is rectified and amplified
• DC power signal is analyzed
• 2-D Location outputs to Computer, LCD, or PDA
• Bill Murray still confused.
TransmitterReceiveAntenna
DCConverter
A/D Microcontroller
Antenna 1
Antenna 2
Possibly:ConstructAntenna 3
PC LocationAlgorithm
Output: Display
Output: Direction
Antenna Array Block Diagram
System Block Diagram
6
8
88
+
Phase Shifters
Shottky Diode / Rectifier / Filter
Antenna Array Design
Digital Control pins
50 Ω line
λ/4(1/εr)
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
Phase Shifter Pin-out
Receiving Array:5 Element Power Pattern
0 deg 10 deg 20 deg
30 deg 40 deg
Receiving Array:7 Element Power Pattern
0 deg 10 deg 20 deg
30 deg 40 deg
Rectification to Amplification:2.4-2.5 GHz Power Signal rectified immediately
Using a Schottky Diode: Surface Mount Low Barrier X-Band: MACOM part # MA4E2054
RF input RF input On Antenna On Antenna BoardBoard DC output DC output
To control BoardTo control Board
Schottky Diode output will be a low level DC Voltage (~mV)Amplification must take place to guarantee proper A/D conversion:Amplification using LF356 op-amp (easy, low noise, cheap)
Antenna Signal Filtering:
Implementing a LF356 op-amp to create a “Sallen-Key” Low Pass Filter
Design Design ffcc = 5kHz = 5kHz
Additional LPF with RC filterAdditional LPF with RC filter
MC68HC11 A/D
One of 8 channels implemented (PE0: pin59)
OPTION control Register: on start-up $1039 (enable A/D):
ADPU: A/D Power Up: (1) Enables A/D capabilities CSEL: Clock Select Enable: (0) Use E Clock (2Mhz)
A/D Control/Status Register: (ADCTL) $1030 (Define A/D parameters): __000000
SCAN: Continuous Scan Control bit: (0) not used MULT: Multiple-Channel Control bit: (0) single channel used CD,CC,CB,CA: Channel Select Bits: 0000 = PE0
Processor, Bus Driver, and Latches
Chip Select, EPROM, SRAM
Antenna Control
Communication with Peripherals
RS-232 interface with userUse a CAN bus to link antennas A balanced, 2-wire interface running
over a Shielded Twisted Pair
NRZ encoding reduces disturbances
CAN bus RS-
232
Software Executive
Main Loop Task specific - latch data gathered on command Subtasks
Read data on latches Compare data from latches to determine highest
power reading Find a location with a simple distance algorithm:
Output visual display on a dummy terminal for user
Antenna 1 Antenna 2
Transmitter
øz
d
* Know Z and ø, can find d
Updated Schedule:
Labor Division for 1st Milestone
Chris Antenna designed and tested (including Shottky diode) PCB board submitted for build
Jake/Kara Control board running and tested (inputs and outputs) Begin software implementation
Mike Ordering phase shifter and Shottky diode Amplifier designed and tested on control perf board
Marcus Transmitter designed and tested Wire-wrap the transmitter on a perf board
COSTS (EXPECTED)
Received $1191 from UROP 1191Phase Shifters cost -725
Need 5 shifters per array = 5*2*72.50
PCB boards 33.00*3 -99General supplies used thus far -100
Wire wrap, resistors, caps, chips, etc.
Remaining funds = 267
Questions?