Transcript Polarimetric Solid State Radar Design for CASA Student

Polarimetric Solid State Radar
Design for CASA Student Test
Bed
Alexandra Litchfield
Objective
 To design a Dual Polarimetric Solid State
Doppler Radar for the CASA student Test
Bed.
Possible Radar Localization @ Aguadilla, PR
Possible Radar Localization @ Mayaguez, PR
Why Solid Sate
Definition:
 Solid State Devices and
Systems are based entirely
on semiconductor.
 There is no mechanical
action on a solid state
device but electromagnetic
action takes place.
 Current is confined to
solid elements.
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Advantages:
Does not need a high
voltage modulator.
Use less power (kW from
Magnetron are eliminated)
Coherent radars can be
made.
Pulse Compression can be
used.
Radar Requirements
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Radar Freq: 9.5-9.6 GHz (X Band)
Peak Transmitter Power: 25W
Minimum Detectable Signal Power: -100dBm
Antenna Gain: 12dB
Horizontal Antenna Beam Width: 6 degrees
Vertical Antenna Beam Width: 6 degrees
Pulse Width: 30us
Max Range: 6km
Project Phases
 Radar Front End
 TR Module
 Transmit/Receive Module Circuit Design
 Component Layouts
 Build and Test
 Phase shifter
 Phase shifter circuit design
 Component Layouts
 Build and Test
 Master clock distribution
 Digital Signal Processing
 Antenna Implementation
 Integration
TR Original Preliminary Design
Transmit Path
IF
Directional
Coupler
PA
Circ.
Limiter
Power
Combiner
S
LNA
Calibration Path
IF
Receiver Path
OSC
Preliminary
Design for
Radar Front
End
Power
Combiner
Cal
S
LNA
PreA
PA
RF
Tx
Rx
LO
Ø
Phase
shifter
Phase
shifter
Ø
Divider /
Combiner
Tx
Rx
IF
Phase Shifter Preliminary Design
90 Hybrid
Variable Amp.
90 Hybrid
∑
∑
I
Q
90 Hybrid
Ø
Q
I
Vcc2
Design with
Vector Modulator
Phase Shifter
Tx
IF2
I
Q
IF2
RF
Vector
Mod
Vcc1
Circ.
LO2
IF2
20MHz
I
Limiter
Noise
Power
Combiner
Q
Directional
Coupler
PA
Rx
LNA
LO1
IF
LO2
Vector
Mod
Vcc1
Vcc2
20MHz
LO1
IF1
IF1
I
Q
One
Polarization
Channel
LNA
PA
Limiter
Receive Path
Cal Path
Power
Combiner
Transmit Path
Directional
Coupler
Circ.
Noise
LO2
Vcc2
IF2
Vector
Mod
Phase shifter
LO1
Vcc1
LO1
IF1
IF1
Components
 Mixer: Alters the carrier
frequency of the signal.
 Oscillator: Controls the
frequency used to
sincronized the radar.
 Directional Coupler /
Power Divider: Couples
part of the transmision
power in to the
transmision line.
 Limiter: Circuit that
allows to pass the
unaffected received signal
 Low Noise Amplifier
(LNA): Amplifies weak
signals captured by the
antenna.
 Circulator: Redirect signal
that comes in an out
from/to transmisor and
receptor.
Radar’s Dual Polarized Antenna
 Dual polarization
Antenna Operating at
9.5GHz
 Array of Apertured
Coupled Antennas
Received Power Calculations
 G=16dB; Ganancia
 R=6km; Maximum Range
 C=3x10^8 m/s; velocity of
light
 Pt=2W Power Transmitted
by each channel.
 H=30usec; Pulse Width
 F= 9.5 GHz
 Lambda=c/f =.031579
 K=dielectric factor (.93
for water)
 Z=10dBz;
10=10log(P), P=10
 MDS = -100dBm
 N=2.66x10^9
 G=39.81W
 Pr=1uW=-30dBm
Component Layout
Power Amplifier
HMC48LP5
Low Noise Amplifier
HMC564LC4
Component Layout
Mixer
HMC412M58G
Future Work
 To construct and measure parameters for the
TR Module and Phase Shifter.
 Digital Signal Processing.
 Antenna Implementation
 Integration
 Test and Measure
Questions