Electronic System DesignElectronic System DesignWireless 1 PresentationWireless 1 Presentation
Dec 7th, 2000
Dec7th 2000
Overview• Objective• Group Designations• Timeline• System Overview
– USB Interface Robert– TRF6900 Transceiver Robert– Antenna Jimmy– Testing Imran– Packaging Jason
• Summary & Conclusions Clay• Demonstration
Dec7th 2000
Objective
• Wireless Communication B/W PC1 & PC2 via USB Port
CommunicationSystem
PC 1
CommunicationSystem
PC 2
Dec7th 2000
Group Designation
Wireless Group 1
EVM Group USB Group Antenna Group Testing Group Packaging Group
Operation ofTRF6900
Package for FinalProduct
Test Plan&
Hardware Issues
Antenna forTransmission
USB Interface b/wPC & TRF6900
Dec7th 2000
System Overview
EZ-USB ParallelOut
USBPort
USB Group
ParallelPort TRF6900
EVM Group
RX_DATAFilteringCircuit
Testing Group
MechanicalAntennaSwitch
Antenna
Antenna Group
Packaging Group
USB Interface & Software USB Interface & Software GroupGroup
Group LeaderRobert Dickerson
Group MembersClay AyersAsad Khan
TI SoftwareTI Software•Used to diagnose and setup the TRF6900•Parallel port problems
•Lacked the ability to be used with the USBSIMM•Inability to cancel a diagnostic test pattern
““Improved” TI SoftwareImproved” TI Software
““Improved” TI SoftwareImproved” TI Software
•Automatically selects USBSIMM when connected
•Non-integer testing durations
•Option to reset settings to default when switching between TX/RX modes•Changed frequency error adjustment to amount of error in the signal
•Will program the TRF6900 with the parallel port
InstantSquawkerInstantSquawker
InstantSquawkerInstantSquawker
•Chat program with file transfer capabilities•Uses a basic protocol between itself and the USBSIMM board•Automatically detects and interfaces with the
USBSIMM module and programs the TRF6900 on connection
USB FirmwareUSB FirmwareStarting Point
Initialize USBSIMM
Reset and Disable TRF6900
Do Nothing in Main Loop
USB FirmwareUSB Firmware
•Setup packets from the PC
•PC request to read the IN buffer
•Serial port TX/RX
•Data packets to send over the RF link
EVM Group PresentationEVM Group PresentationGroup Leader: Imran Bashir
Members: Jeff Allen, Asad Khan, Fakhri Sadeh, Wendy Johnston,
Jason Benavidez
Dec 7th, 2000
Dec7th 2000
Overview
• TRF6900 Transceiver• Transmitter• Receiver• General Specifications• Why TRF6900?
Dec7th 2000
TRF6900 Transceiver
Dec7th 2000
Transmitter
Serial Interface
Data
Clock
Strobe
Direct Digital Synthesizer (DDS)
Crystal Oscillator
PLL VCO Tank Circuit
Filter / Impedance Matching
LOCKDET
VCO
Antenna
2nd Order Loop Filter
AmplifierAmplifierPowerAmplifier
Mode
STDBY
TX_DATA
Dec7th 2000
Receiver
Impedance Matching
Carrier
Data Slicer Data Switch FM / FSK
Demodulator
Tank Circuit
External Circuit for
LPF
Capacitor for VREF
RX_DATA
LNA RF Amplifier
RSSI (OOK/ASK)
Pre-Select Filter IF Amplifier (1)
IF Amplifier (2)
BPF (1) BPF (1)
LPF Amplifier/ Post Detection
Amplifier
Antenna
Dec7th 2000
SpecificationsTRF6900
48-pin PQFPPackage
2Standby Current (A)
2.2 – 3.6Operating Voltage (Volts)
5Power Output (dBm)
FSK, narrow-band FMStandard Supported
850-950Frequency (MHz)
TRF6900Parameter Name
Dec7th 2000
Why TRF6900?
• Availability• Donation from Texas Instruments• Suitable for the Project’s Objective• Availability of Reference Material &
Technical Support
ANTENNA DESIGN GROUP
James FurseAden Wilson
Dec7th 2000
Objectives – Antenna Design
• Compact Design
• Center Frequency of 915 MHz
• Low VSWR
• High Gain
• Circular Polarization
Dec7th 2000
Objectives – RX/TX Switching
• Low Insertion Loss
• Fast Switching Speed
• TTL Level Input
Dec7th 2000
Antenna Design Scheme
• Initial antenna design and evaluation• Optimize characteristics by varying antenna
dimensions and configuration• Perform preliminary tests with network
analyzer to determine effects of changes• Implement desirable modifications and
perform radiation pattern and gain tests
Dec7th 2000
Experimental Modifications • Increased ground plane area • Increased pitch angle
• Varied helix diameter
• Varied number of helix turns
• Implemented shunt feed configuration
Dec7th 2000
Equipment Setup for Radiation Pattern And Gain Measurements
Anechoic Chamber
AntennaUnderTest
ProbeAntenna
NetworkAnalyzer
PC(Data
Collection)
Dec7th 2000
Anechoic Chamber Setup
Dec7th 2000
Network Analyzer and Antenna Rotation Unit
Dec7th 2000
Milestones
• 10/01/00 Select Antenna Design
• 10/08/00 Complete Prototype
• 11/15/00 Implement RX/TX Switch
• 11/20/00 Successful PC to PC Communication
• 12/05/00 Design Complete
Dec7th 2000
NMHA Operation
• Normal Mode
• Self Resonance
• Direction of Maximum Radiation
• Elliptical Polarization
• Ideal E-Plane Radiation Pattern
Dec7th 2000
Ideal E-Plane Radiation Pattern
sin4
)( 2bjsReINE
Rjo
Dec7th 2000
Final Antenna Design
Dec7th 2000
Antenna Specifications
• Turns 5• Diameter .3125• Spacing .48 • Pitch Angle 26 • Helix Length 2.4 • Shunt Feed Configuration
Dec7th 2000
Network Analyzer – Return Loss
Dec7th 2000
Network Analyzer – Smith Chart
Dec7th 2000
Network Analyzer - VSWR
Dec7th 2000
Anechoic Chamber Measurements
90 deg
270 deg
180 deg 0 deg
H-Plane Radiation Pattern (915 MHz)
Dec7th 2000
Anechoic Chamber Measurements
90 deg
270 deg
180 deg 0 deg
E-Plane Radiation Pattern (915 MHz)
Dec7th 2000
Anechoic Chamber Measurements
900 905 910 915 920 925 9300
1
2
3
4Measured Gain
Frequency in MHz
dB
Dec7th 2000
RX/TX Switching
Normal ModeHelical AntennaRX/TX Switch
RX
TX
Testing Group PresentationTesting Group Presentation
Group Leader: Imran BashirMembers:
Jeffery Allen, Asad Khan, Fakhri Sadeh, Farhan Khan
Dec 7th, 2000
Dec7th 2000
Overview
• Test Setup• Software Issues
– Speed– RSSI
• Hardware Issue– RX_DATA– Solution
• Design 1• Design 2
– Final Circuit
Dec7th 2000
Test Setup
8 V
Duplexer TRF6900 EVMRX_DAT
A
O’scopeOR
Logic Analyzer
PC (RX)
Running TRF6900.exe
Ver. Beta3
DB25 femaleTo DB25 male
EZ-USB USB Port
Parallel OutTRF6900 EVM
TX_DATA
O’scopeOR
Logic Analyzer
PC (TX)
Running TRF6900.exeVer. Beta 3
DB25 femaleTo DB25 male
EZ-USB ParallelOut
USBPort Duplexer
D.C. Power Supply
8 V
Dec7th 2000
Software Issues
• Speed– Modified Software for Faster PCs
• RSSI– Very Weak Signal from TRF6900– Turn RSSI “ON” in Software
Dec7th 2000
Hardware IssuesNoise Issue
• Spikes on RX_DATA During FSK Test
Voltage Spikes
Dec7th 2000
Hardware IssuesNoise Issue
• Noise on RX_DATA After FSK Test
Dec7th 2000
Hardware IssuesNoise Issue: Solution
Vcc
Input A
Input B
GND
Input A Input B Output
Dec7th 2000
Hardware IssuesNoise Issue: Solution
• 1st Design
TLV3402 Analog Comparator
Dec7th 2000
Hardware IssuesNoise Issue: Solution
• Problem:– RSSI Signal is High After FSK Test
During FSK Test
After FSK Test
Dec7th 2000
Hardware IssuesNoise Issue: Solution
• 2nd Design
• Cleans Spikes in RX_DATA• High Output After FSK Test
Dec7th 2000
Packaging Group
Group LeaderJason Benavidez
Group MembersWendy Johnston
Jeff Allen
Dec7th 2000
Group Objectives
• Packaging the EVM Board, USB SIMM Board, Antenna, and All Related Components for Testing Purposes
• Construct Necessary Jumpers and Connections Internal to the Device
• Design and Fabricate a Single Package Solution for Final Commercial Product
Initial Packaging
Dec7th 2000
Initial Packaging DesignBlock Diagram
EVM BOARD
POWER CONNECTIONS
PARALLEL PORT SMA CONNECTORS TO RX/TX
OSCILLOSCOPE CONNECTIONS TO BOARD
PWR SWITCH
USBSIMM
USB PORT
PWR (adapter)
IN
Yellow represents future upgrades
Dec7th 2000
Initial Design Features
• Provide Protection & Stability for EVM• Provide Permanent Connections for Power
Supply From External DC Power Source• Allow Easy Access to RX/TX Data Terminals
for Testing Purposes• Allow Easy Hook up to Testing Equipment
Dec7th 2000
Initial Package Design
Dec7th 2000
Package Layout
Final Packaging
Dec7th 2000
Final Packaging DesignBlock Diagram
EVM BOARD
PWR SWITCH
USBSIMM
USB PORT
PWRIN
10-12 V
ANTENNA SWITCH
POTPARALLEL
PORT
PWRIN
28 V
LOGIC CIRCUIT
VOLTAGE REGULATOR
5 V
VOLTAGE REGULATOR
8 V
Dec7th 2000
Final Design Features
• USB Data Input Capability• Lighted On/Off Switch• Impact Resistant Polystyrene Box• Internalized Antenna
Dec7th 2000
Final Package
Dec7th 2000
Final Package
Dec7th 2000
Final Package
Dec7th 2000
Project Demonstration
Dec7th 2000
Supporters
•Texas Instruments
•Mousers Electronics