AIP/123-QED Local oscillator phase noise limitation on the resolution of acoustic delay line wireless passive sensor measurement N. Chr´ etien, 1 J.-M Friedt, 1, a) and G. Martin 2 1) SENSeOR SAS, Besan¸ con, France 2) FEMTO-ST, Time & frequency department, UMR CNRS 6174, Univ. Franche Comt´ e, Besan¸ con, France (Dated: 19 March 2014) The role of the phase noise of a local oscillator driving a pulsed-mode RADAR used for probing surface acoustic wave sensors is investigated. The echo delay, representa- tive of the acoustic velocity and hence the physical quantity probed by the sensor, is finely measured as a phase. Considering that the intrinsic oscillator phase fluctuation defines the phase noise measurement resolution, we experimentally and theoretically assess the relation between phase noise, measurement range and measurand resolu- tion. PACS numbers: 84.40.-x,43.20.Ye, 43.38.Rh Keywords: phase noise, wireless, battery-less, surface acoustic wave, delay line, RADAR a) Electronic mail: [email protected]; http://jmfriedt.free.fr 1
17
Embed
Local oscillator phase noise limitation on the resolution ...jmfriedt.free.fr/rsi_nico.pdf · AIP/123-QED Local oscillator phase noise limitation on the resolution of acoustic delay
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
AIP/123-QED
Local oscillator phase noise limitation on the resolution of acoustic delay line wireless
passive sensor measurement
N. Chretien,1 J.-M Friedt,1, a) and G. Martin2
1)SENSeOR SAS, Besancon, France
2)FEMTO-ST, Time & frequency department, UMR CNRS 6174,
Univ. Franche Comte, Besancon, France
(Dated: 19 March 2014)
The role of the phase noise of a local oscillator driving a pulsed-mode RADAR used
for probing surface acoustic wave sensors is investigated. The echo delay, representa-
tive of the acoustic velocity and hence the physical quantity probed by the sensor, is
finely measured as a phase. Considering that the intrinsic oscillator phase fluctuation
defines the phase noise measurement resolution, we experimentally and theoretically
assess the relation between phase noise, measurement range and measurand resolu-
16V. Kalinin, B. Dixon, and J. Beckley. Optimization of resonant frequency measurement
algorithm for wireless passive SAW sensors. In Joint 22nd European Frequency and Time
forum and IEEE International Frequency Control Symposium, pages 90–95, 2009.
17J. H. Kuypers, L. M. Reindl, S. Tanaka, and M. Esashi. Maximum accuracy evaluation
scheme for wireless SAW delay-line sensors. IEEE Transactions on ultrasonics, ferro-
electrics, and frequency control, 55(7), July 2008.
18J. H. Kuypers, S. Tanaka, M. Esashi, D. A. Eisele, and L. M. Reindl. Passive 2.45 GHz
TDMA based multi-sensor wireless temperature monitoring system: Results and design
considerations. In IEEE Ultrasonics Symposium, pages 1453–1458, 2006.
19V.P. Plessky and L.M. Reindl. Review on SAW RFID tags. IEEE Trans Ultrason Ferro-
electr Freq Control, 57(3):654–668, Mar 2010.
20E. Rubiola. Phase Noise and Frequency Stability in Oscillators. Cambridge University
Press, 2010.
9
LIST OF FIGURES
1 Basics of a pulsed-mode SAW delay line acoustic sensor interrogation schemeemphasizing the influence of the local oscillator phase noise. The source at afixed frequency ν is gated at time t and the signal returns after a time τ in-cluding the electromagnetic and acoustic propagation durations. Throughoutthe discussion, the offset from the carrier f = 1/τ is considered. The com-ponent references are those used to demonstrate experimentally the conceptsdeveloped in this paper. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2 I and Q component measurements of an acoustic delay line probed by variousradiofrequency sources characterized by different phase noise distributions.Although the contribution of the phase noise is hardly visible on these rawdata, the emphasis is on the operation at constant received power for all testerradiofrequency sources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3 Phase noise of the sources considered in this document for probing a 2450 MHzacoustic delay line acting as passive sensor. Although the Agilent sourcesignificantly fluctuates around the frequency offset from carrier of interest, thephase noise value of -127 dBrad2/Hz was selected to best match experimentalresults. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4 Phase measurement standard deviation as a function of the echo delay. The3 dB rise with respect to the raw oscillator phase noise measurement is associ-ated with adding the noise contributions of the two inputs during the mixingprocess. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5 Conversion from phase noise to temperature measurement, considering a2 GHz measurement bandwidth (4 GS/s digital oscilloscope records): no-tice that the rising phase noise with delay is compensated for by the risingsensitivity with increasing delay. The dashed lines indicate the expected tem-perature measurement standard deviation for nominal phase noise values plusor minus 1 dBrad2/Hz and hence act as error bars. . . . . . . . . . . . . . . . . . . . . . . . 15
10
SAW delayline sensor
monostaticantenna
configuration (t− )τν
I co
mp
on
ent
source(t)ν
ZX60−272LN+Minicircuits
τ
MinicircuitsZX60−272LN+HMC286
Hittite
ZASWA−2−50DR+
FIG. 1. Basics of a pulsed-mode SAW delay line acoustic sensor interrogation scheme emphasizing
the influence of the local oscillator phase noise. The source at a fixed frequency ν is gated at time
t and the signal returns after a time τ including the electromagnetic and acoustic propagation
durations. Throughout the discussion, the offset from the carrier f = 1/τ is considered. The
component references are those used to demonstrate experimentally the concepts developed in this
paper.
11
0.0
0.1
0.2
0.3
0.4
0.5
0.5 1.0 1.5 2.0 2.5 3.0
|I+
jQ| (
V)
time (us)
Marconidegraded Marconi
Agilent
AgilentMarconi
degraded Marconi
FIG. 2. I and Q component measurements of an acoustic delay line probed by various radiofre-
quency sources characterized by different phase noise distributions. Although the contribution of
the phase noise is hardly visible on these raw data, the emphasis is on the operation at constant
received power for all tester radiofrequency sources.
12
-150
-140
-130
-120
-110
-100
-90
103
104
105
106
107
L(f
) (d
Bc/
Hz)
f (Hz) 1/τ(sensor)
Agilent
degraded Marconi
Marconi
FIG. 3. Phase noise of the sources considered in this document for probing a 2450 MHz acoustic
delay line acting as passive sensor. Although the Agilent source significantly fluctuates around the
frequency offset from carrier of interest, the phase noise value of -127 dBrad2/Hz was selected to
best match experimental results.
13
0.010
0.015
0.020
0.025
0.030
0.035
0.040
0.045
0.050
1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4
σ φ
(rad)
τ (us)
Agilent
degradedMarconi
Marconi
L(f)=-124 dBc/Hz
L(f)=-130 dBc/Hz
L(f)=-135 dBc/Hz
FIG. 4. Phase measurement standard deviation as a function of the echo delay. The 3 dB rise
with respect to the raw oscillator phase noise measurement is associated with adding the noise
contributions of the two inputs during the mixing process.
14
0.00
0.01
0.02
0.03
0.04
0.05
1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4
∆T (K)
Marconi
degradedMarconi
Agilent
τ (us)
FIG. 5. Conversion from phase noise to temperature measurement, considering a 2 GHz mea-
surement bandwidth (4 GS/s digital oscilloscope records): notice that the rising phase noise with
delay is compensated for by the rising sensitivity with increasing delay. The dashed lines indicate
the expected temperature measurement standard deviation for nominal phase noise values plus or
minus 1 dBrad2/Hz and hence act as error bars.
15
LIST OF TABLES
I Influence of local oscillator phase noise and sensor geometry on the measure-ment resolution. The single sideband phase noise L(f) is related to the phasenoise Sϕ by a factor of 2 during the numerical application. . . . . . . . . . . . . . . . . 17
16
TABLE I. Influence of local oscillator phase noise and sensor geometry on the measurement res-
olution. The single sideband phase noise L(f) is related to the phase noise Sϕ by a factor of 2