Transcript Slide 1

Instrumentation Development for the Measurement and Characterisation
of Indoor and Urban Canyon Ambient Noise Floor in the Galileo Frequency Bands
I3S Institute
CAA ISN Research Group
Measurement Instrument
1
M. Junered and D. Akos, Luleå University of Technology, Sweden
M. Adjrad, L. E. Aguado, M. Daly, and A. H. Kemp, The University of Leeds, UK
NAVITEC '2006, 11-13 December 2006
Major Components:
Wideband antenna.
5 metre low-loss cable.
Front-end.
Spectrum Analyzer.
Notebook Computer:
Runs Matlab® software.
Controls the switches.
Configures/Controls the
spectrum analyzer.
Data Acquisition Card.
Novatel GPS704X Antenna
2
L1
3
L5/E5a
Technical Features:
Passive antenna.
3 dB passband 1.15 GHz – 1.65
GHz.
Gain at zenith (90°):
L1 + 6.0 dBic (minimum).
L5, E5a + 2.0 dBic (minimum).
E6 + 3.0 dBic (minimum).
VSWR ≤ 2.0 : 1.
Pinwheel technology:
Multipath rejection.
Phase stability.
MOTIVATION
4
GNSS Research Group
EIS Laboratory
Front-End
Galileo system will offer new frequency bands as well as share existing spectrum with parallel systems.
Development of the Galileo system will significantly improve on existing accuracy, availability, reliability and
integrity.
Indoors and urban canyons are typical environment for emergency services, GNSS for caller location, etc.
Significant performance loss in urban canyon and indoor locations due to high levels of attenuation, signal
masking and multipath.
Great impact of accurate characterization of signal and noise environments on receiver design.
The effect on the noise floor in the sensitive Galileo bands from the proliferation of electronic devices is largely
unknown.
PROJECT
Unintentional man-made noise measuring receiver design utilizing commercially available equipment to
characterise the indoor and urban canyon existing interferences in the various frequency bands in which Galileo will
operate.
Presentation of design trade-offs and initial instrument testing.
A joint measurements campaign between Luleå Technical University and the University of Leeds.
Technical Features:
RF switches: Mechanical relay
Low insertion loss ~0.2 dB.
VSWR 1.2:1.
Isolation 80 dB (min).
Actuating current ~0.15 A@28V.
TTL Control.
Indicator circuitry.
Triplexer: Custom order from Delta
Microwave
Passbands:
-1559 to 1591 MHz.
-1260 to 1300 MHz.
-1164 to 1214 MHz.
Insertion Loss 0.75dB.
VSWR1.3:1.
40 dB Bandwidth +/- 100 MHz
Max.
Connectors:
-1 SMA Female (in).
-3 SMA Female (out).
LNA: Minicircuits XHL-1217HLN
Frequency 1.2 GHz –1.7 GHz.
Noise Figure 1.5 dB.
Gain 30 dB (min).
VSWR 2.4:1.
Power consumption 725 mA @
15V.
Case style NN92 = big heatsink.
MEASUREMENTS
Spectrum Analyzer Configuration/ Measurement Scheme:
Measurement Example:
Location/Duration: The university of Leeds computing laboratory / 48 hours test, Friday-Saturday.
Spectrum analyzer settings: 1 kHz resolution bandwidth, Detector: RMS, Trace mode: Clear/Write.
Spectrum Analyzer
Technical Features:
Frequency range 100 kHz to 3 GHz.
Internal preamplifier (frequency range
100 kHz - 3 GHz).
Displayed average noise level -135
dBm typical (RBW 100 Hz).
High level accuracy 0.5 dB typical.
Resolution bandwidths 100Hz to1MHz.
Wide range of detectors:
Sample.
Max/Min Peak.
Auto Peak.
RMS.
CONCLUSIONS
Galileo E5, E6, and L1 band monitoring.
Instrument:
Sensitivity of -143 dBm at the instrument antenna port using 1 kHz resolution bandwidth.
Automatic control/configuration of the spectrum analyzer and the front-end.
Components carefully selected in particular with respect to minimize the noise figure of the front-end.
Theoretical and measured noise floor levels match.
Noise Figure 3.6 dB for the front-end and 2 dB from the antenna port to the LNA input.
Interference characterization:
Characterize interference as a function of time and location.
Correlation between interference and activity (specific for each location).
Updates on the instrument and measurement campaign will be available on:
http://www.engineering.leeds.ac.uk/i3s/research/Sat_Nav_wire/qgn_project.shtml
5
EMC Chamber Test
REFERENCES
[1] Galileo Open Service, Signal In Space Interface Control Document (OS SIS ICD), Draft 0, European Space Agency/ Galileo Joint Undertaking, 2006.
[2] G. Brodin, A. Kemp, D. Akos, J. Cooper, “Quantification of the potential threat to Galileo from Man-made Noise sources (QGN),” Technical proposal, in
response to GJU call 2423, September 2004.
[3] J. Do, D. M. Akos, and P. K. Enge, “L and S Bands Spectrum Survey in the San Francisco Bay Area,” Position Location and Navigation Symposium,
PLANS 2004, 26-29 April 2004.
[4] M. O’Donnell, T. Watson, J. Fisher, S. Simpson, G. Brodin, E. Bryant, and D. Walsh, “GPS Interoperability and Discriminators for Urban and Indoor
Environments,” GPS World (invited article), Advanstar Communications, June 2003.
[5] “Quantification of the potential threat to Galileo from man-made Noise sources (QGN), Deliverable D1a – System requirements,” GJU Research &
Development, 2nd Call, Area 3, July 2006.
The QGN project is managed by the Galileo Joint Undertaking through EU 6FP funds