programmable delay of radar pulse
DESCRIPTION
Technion-Israel Institute of Technology Electrical Engineering Department. Programmable Delay of Radar Pulse. Final Presentation of Part A Project number: d1022 November 2003. Students: Guy Apelbaum Yoel Taran Supervisors: Miki Izkovitz Yosi Hipsh. Project Goal. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/1.jpg)
Programmable Delay of Radar Pulse
Technion-Israel Institute of Technology
Electrical Engineering Department
![Page 2: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/2.jpg)
Final Presentation of Part AProject number: d1022 November 2003
Students: Guy Apelbaum
Yoel Taran
Supervisors: Miki Izkovitz
Yosi Hipsh
![Page 3: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/3.jpg)
Project Goal
• Implementation of an accurate delay system(DS)
• System receives a pulse as input and transmits it delayed with a given value to RF switch
Delay SystemIn Out
Delay Value
PulseDelayed Pulse to
RF switch
![Page 4: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/4.jpg)
Specifications
• Pulse’s appearance frequency lower then 1.5 MHz
• Delay value : at range of 1 to 256 nsec
• Delay resolution : 0.5 nsec
• Pulse width greater then 30 nsec
• System operates with pulses at TTL level
![Page 5: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/5.jpg)
General Guidelines
• DS implemented as layout
• Connected to a PC to communicate with a user
• The connection is available through a control system
![Page 6: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/6.jpg)
Control System
Main Functionality : Connection between user and DS
Features :
Transferring value of delay from PC to DS
Performing different delay modes
User’sPC
ControlSystem
DelaySystem
![Page 7: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/7.jpg)
Project Flow
StartDefinition of Problem
Solution Proposal
HardwareImplementation
SoftwareImplementation
ImplementationOf Chosen Solution
![Page 8: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/8.jpg)
Background
The DS implemented here will be a part of ECM system
Radar(we trick) works as follows : Time*Velocity = Position
where
Time = (time of propagation to the target)
Velocity = speed of wave
Position = distance from radar to the target
![Page 9: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/9.jpg)
DS : delays the signal and shifts the Time calculated by radaradditionally, it increases the energy of the delayed pulsethus, constantly delaying pulses we make radar follow the wrong destination !
![Page 10: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/10.jpg)
Possible Solutions for DS
Use of high-frequency clock (~1 GHz)
• The clock starts counting while receiving pulse at input
• When reaching the desired delay value pulse is created and is sent to RF switch
CounterClk(~1GHz)
Pulse Generator
Pulse IN Pulse OUT
![Page 11: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/11.jpg)
Advantages:No pre-calibration of the DS is required Clocks satisfying the desired resolution are available
Disadvantages:The demand for 0.5 nsec resolution requires creating pulses with short t_riseImplementation of successful pulse generator is
problematic and requires use of high speed digital technology
Radar pulse’s shape is unknown – what shape to generate?
![Page 12: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/12.jpg)
Use of delay linesTwo delay lines connected in cascade
First line : delay range from 1 to 256 nsec resolution of 1 nsec
Second line : delay range from 1 to 64 nsec resolution of 0.25 nsec
Result : 1 to 256 nsec range is achievedResolution of the total delay is 0.25 nsec
First Line Second Line
X
X +/- Dev
Y -/+ Dev
X+YX + Y
Desired Delay
![Page 13: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/13.jpg)
Advantages:No need in creating pulse , the original one is just delayed
Original pulse’s shape is maintained
Delay lines answering given specifications are available&cheap
Disadvantages:
The DS need to be calibrated before operating
Calibration data need to be stored = additional memory
![Page 14: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/14.jpg)
The chosen one ?
And that’s because of :
Simplicity of algorithm used to achieve desired resolution
Avoidance of dealing with high speed technology
Relatively cheap prices for DS future components
Delay Lines!
![Page 15: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/15.jpg)
Implementation of the chosen solution:
Hardware implementation
circuit connecting between PC , controller and DS
at first – implementation as wire-up circuit
then – implementation as printed layout circuit
Software implementation
programming the controller which will watch after proper functioning of the system
![Page 16: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/16.jpg)
Schematic view of the wire-up to be built
Delay System
PC
In Out
Controller
Delay Data
ORgate
DIP switches
For test proposals – manual controller implemented by dip switches was added
![Page 17: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/17.jpg)
Functionality’s DescriptionDelay Lines
3D7408-1 and 3D7408-0.25 lines manufactured by Data Delay Devices
Function : delaying pulse at given value
3D7408-1 3D7408-0.25
8 bit input data is all needed for delay lines to function properly The rest of pins are under stable logic value
![Page 18: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/18.jpg)
Controller – implemented by PIC 18f252 manufactured by Microchip
Functions :
communication with user’s PC
communication with delay lines
write/read operations with external memory
storage of several delay modes applied to DS
PIC 18f252
28 I/O pins
2 Mb Program Memory
USART,I^2C modules
![Page 19: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/19.jpg)
PIC as a controller of the system - Detailed View
ICD 2 Plus demonstration board
PIC 18f252
RS-232
Oscilator
Power
PC’sGUI
3D7408-1 3D7408-0.25
EEPROM
USART I^2C
![Page 20: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/20.jpg)
PC – any personal computer with RS232 serial port available
Functions :
read/write operations to/from controller
presentation of essential information on the screen
![Page 21: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/21.jpg)
Hardware Characteristics
Voltage and Power
All units operate of 5 V DC
Current driven by the circuit – 350 mA
Implementation: Power Source of 9 V AC driving 400 mA entering 5 V DC voltage regulator
Speed Rates
1.5 MHz – delay lines max speed
4 MHz – PIC clock frequency
![Page 22: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/22.jpg)
Memory
2 Mb program memory on PIC
256 bytes x 5 RAM on PIC
256 Kbytes x 8 EEPROM on demo board
Interfaces
GUI : PC – user interface. Implemented by Terminal v1.9b
UART : PC – PIC interface. Implemented by USART module
located on PIC . Communication via RS232 port
![Page 23: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/23.jpg)
Program Flow
Idleinitialization
1Storage of
Delay Values
2DelayModes
Prompts:1-Calibration
2-Delay
![Page 24: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/24.jpg)
Calibration
Storage ofDelay Values
Prompts:1-Manually2-Automatic
1User enters value
It is stored in RAM
2Data file sent
It is stored in RAM
![Page 25: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/25.jpg)
Notes for Calibration:
The process is done offline
Precedes delay operations
The data is stored in RAM (at this point)
The data will be stored in EEPROM(soon)
![Page 26: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/26.jpg)
Delay
DelayModes
Prompts:1-Constant Delay
2-Changing Delay(Ch.D)3-Manually Ch.D
3Value of Delay
Is ManuallyEntered
2Pulse DelayIs Changed
With a Given Step
1Pulse DelayedBy a Constant
Value
![Page 27: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/27.jpg)
Notes for Delay operations:
After user transfers delay value it is assigned to
delay lines pins by PIC
“Enter” pushed during any mode = back to main menu
![Page 28: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/28.jpg)
Software Specifications
Development tool to program PIC – ICD 2 Plus demo board
compiler – MPLAB C18
emulator – MPLAB ICE 2000
debugger – MPLAB ICD 2
programmer – PICSTART +
![Page 29: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/29.jpg)
Testing
Delay line tested by Tektronix 500 MHz Digital Scope
good performance – in limitation of measuring equipment
Digital Scope
3D7408-1 3D7408-0.25
TP1 TP3
8 DIP Switches 8 DIP Switches
PulseGenerator
![Page 30: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/30.jpg)
PICTesting performed on demo board connected to PC
Value of PIC output pins matched the desired result
![Page 31: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/31.jpg)
Scheme of complete system testing
Digital Scope
3D7408-1 3D7408-0.25
TP1 TP3
PulseGenerator
PIC 18f252PORT B PORT C
PC
![Page 32: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/32.jpg)
To Sum Up Part A of Project
The prototype of the layout was build as wire-up circuit concluding delay lines
The controller was programmed to perform specific delay functions and to communicate with user
Tests showed that delay lines drove by controller do delay pulses at values closed to expected
![Page 33: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/33.jpg)
Conclusion
• As expected – delay lines were functioning well and this gives a reason to be optimistic approaching to
design the layout circuit • To gain desired resolution one needs to consider high
speed effects presented on a line connecting delay devices.To prevent these, impedances should be matched and both delay lines should be placed on
a layout• To measure the actual delay with needed grade of
precision high-frequency (greater then 1 GHz) should be used
![Page 34: Programmable Delay of Radar Pulse](https://reader036.vdocument.in/reader036/viewer/2022062304/56812a7a550346895d8e039d/html5/thumbnails/34.jpg)
Part B Goals
• calibration becomes automatic – tables of desired delay values are filled from scope measurements without users interference
• delay lines are placed on a layout – to prevent reflections
• calibration data stored in EEPROM(external memory)