M. Sc. E.E. MIELNIK Piotr
Institute of Radar Technology
Military University of Technology
Warsaw Poland
GNSS RECEIVER TESTING TECHNIQUES IN
A LABORATORY ENVIRONMENT
Workshop EGNOS KRAKÓW 2004
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Area of activity
the Institute of Radar Technology
connected with satellite navigation systems technique
Jamming cancellation techniques (not only in military aspects - warfare)
Testing the properties of GNSS receivers
Developing and testing of algorithms for INS/GPS receivers
Developing CRPA antennas (adaptive antenna)
Developing pseudosattelite construction (pseudolite)
Developing DGNSS landing systems (LAAS)
Researches in attitude determination receivers area
Researches in time synchronizations area
Workshop EGNOS KRAKÓW 2004
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Jamming cancellation techniques
The works concentrate on three aspects:
 designing antenna systems
null steering and beam forming
 designing specialized receivers
algorithms used before and after correlation
 detection, identification and localization of jamming sources
The following methods are considered:
 controlled antenna pattern
 front-end filtering
 signal detection algorithms (RFI, jamming and spoofing signals)
 signal processing algorithms
 code / carrier tracking loop
 integrated demodulator navigation
Workshop EGNOS KRAKÓW 2004
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Testing the properties of GNSS receiver
Delay Lock Loop
Phase Lock Loop
simulated signal
Data demodulation
Automatic Gain Control
Low Noise Amplifier
Digital
receiver channel
AGC
Antenna
.
Filter
RF
Amplifier
Down
converter
Digital
receiver channel
Digital
receiver channel
A/D
converter
analog IF
.
.
digital IF
other parts
of receiver
Signal conversion
Processing
Algorithms for
data processing and signal monitoring
The essence of the investigations is to find disadvantages of each receiver
Workshop EGNOS KRAKÓW 2004
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Testing new multi frequency receiver constructions
Currently still in Simulink environment
151MHz
26MHz
L1
L1
AGC
Filtr
L1,L2,L5
L5
196MHz
L2
L1
18MHz
L2
L2
A/C
247MHz
AGC
69MHz
L5
L5
AGC
L1 SAW
I
L1
Q
:8
AGC
L2 SAW
I
L2
VCO
PLL
Q
40.92MHz
AGC
L5 SAW
I
L5
Q
AGC
Dzielnik
VCO
PLL-1
PLL-2
IF
VCO
TCXO
Workshop EGNOS KRAKÓW 2004
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Designing and checking algorithms for integrated navigation systems
AHRS
GPS
Chip
& Algorithms implementation
board
The main goal is to construct Embedded GPS/INS module (EGI)
Workshop EGNOS KRAKÓW 2004
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Developing CRPA antennas (adaptive antenna)
These applications request Buttler matrix
Workshop EGNOS KRAKÓW 2004
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Tans Vector – GPS receiver
for attitude determination
Not only for aircraft
navigation
Satellite
Satellite
Satellite
Satellite
ANT 1
ANT 2
ANT 3
ANT 4
RS 422
Computer
Supply
TANS VECTOR
Workshop EGNOS KRAKÓW 2004
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The basis of MUT laboratories
Electronics faculty
The laboratory of digital techniques
Stands to design specialized chips
The laboratory of antenna techniques
Chamber
Avionics laboratory
GNSS simulator
Workshop EGNOS KRAKÓW 2004
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The Avionics Laboratory
at the Institute of Radar Technology
The only device of this class in Poland
Workshop EGNOS KRAKÓW 2004
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The short description of GNSS Simulator
Current Options
• generation of 16 satellite signals (GPS L1, code C/A and P)
• generation of SBAS signals (WAAS, EGNOS, MSAS)
• object remote control in the real time (closed loop)
• simulating the DGPS reference station (with RTCM protocol)
simultaneously to the operation
• simulating the LAAS reference station (with RTCA protocol)
simultaneously to the operation
• simulating the baro altimeter simultaneously to operation
• tools for analyzing the EUT output data in the real time
!
• software that enables to generate data for GPS L2c, L5 and
GLONASS signals
Workshop EGNOS KRAKÓW 2004
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DGPS
LAAS
System
Space
Segment
Signal
propagation
GPS SYSTEM
SBAS
Systems
User
Segment
Workshop EGNOS KRAKÓW 2004
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Space Segment
• satellites orbit motion edition
(to satellite constellation control)
• navigation data control
• ISCN and SA distortion
• satellites signal power control
• satellite transmitter antenna characteristic
edition
Workshop EGNOS KRAKÓW 2004
13
Signal propagation
• iono and tropo- parameters edition
(atmosphere modelling)
• navigation data distortion (with bit resolution)
• multipath simulation
• terrain obstacles simulation
• signal phase and amplitude distortion
modelling
Workshop EGNOS KRAKÓW 2004
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User segment
• vehicle type choice (aircraft, ship, car and
spacecraft) and its dynamics parameters
• vehicle position and motion simulation
• receiver antenna characteristic modelling
• receiver antenna orientation with respect
to Body Axes of vehicle
Workshop EGNOS KRAKÓW 2004
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EGNOS signal
• edition of Monitoring Stations location
• message data control (16 types of messages)
• signal power control
• edition of degradation parameters
• user range error edition
• covariance matrix edition (clock, ephemeris)
• almanac edition
• ionospheric error data edition
Workshop EGNOS KRAKÓW 2004
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Research methodology
Equipment
Under Test
Type of receiver
Data protocols
Laboratory
Basis
Goals
Measurement equipment
Expectations
PROJECT
Workshop EGNOS KRAKÓW 2004
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GNSS receiver performance characteristics studies*
WORKSTATION
GNSS Simulator
RF signal
IEEE - 488
ATT .
DATA COLLECTION
coupler
&
splitter
EUT
JAMMING
GENERATOR
ANALYZER
* This set is used to check some specialized software for awareness situations, too
Workshop EGNOS KRAKÓW 2004
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Examination of GPS receivers for time synchronization
ANT ENNASS
WORKSTATION
GNSS SIMULATOR
RF signal
IEEE - 488
Att.
GPS Receiv er
1
1PPS
T -2200
T ime card
1PPS
splitter
RS 232
coupler
GPS Receiv er
2
1PPS
RS 232
GPS Receiv er
3
1PPS
Data collection
RS 232
GPS Receiv er 4
coupler
1PPS
RS 232
SIGNAL
GENERATOR
Workshop EGNOS KRAKÓW 2004
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CRPA antenna tests research set
WORKSTATION
GNSS Simulator
RF signal
IEEE - 488
ATT .
DATA COLLECTION
Buttler
matrix
Antenna
Control
Unit
EUT
JAMMING
GENERATOR
Workshop EGNOS KRAKÓW 2004
20
Test bench for LAAS application
IEEE - 488
Workstation
RS 232
Vehicle motion
control
in the real time
GNSS Simulator
IEEE - 488
IEEE - 488
RF
signal
Att.
JAMMING
GENERATOR
GPS receiv er
splitter
&
coupler
LAAS protocol
DO 217/DO246
aircraft receiver simulator
a) RTCM 104
b) SV's position
c) SV's pseudorange
RF signal
PSEUDOSATELLITE
ANALY ZER
IEEE - 488
a) aircraf t board receiv er
algorithms implementation
b) data collection
LAAS reference station simulator
pseudolite generator
remote
Workshop EGNOS KRAKÓW 2004
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Thank you
for
attention
Workshop EGNOS KRAKÓW 2004
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