“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?