AX5051 Use in Compliance with ETSI EN 300 220-1

APPLICATION NOTE AND9318/D
AX5051
Use in Compliance with ETSI
EN 300 220-1
Revision 2
2
Table of Contents
1. Introduction................................................................................................ 3
1.1. Receive ........................................................................................................ 3
1.2. Transmit....................................................................................................... 3
2. Measurements ............................................................................................ 4
2.1. General ........................................................................................................ 4
Frequency Error ETSI EN 300 220-1 V2.4.1 (2012-05), Sub-clause 7.1 ................ 4
2.2. 868 MHz wide band, 100 kbps, GFSK ............................................................... 5
Setup ........................................................................................................... 5
Average Power ETSI EN 300 220-1 V2.4.1 (2012-05), Subclause 7.2 ................... 6
Transient Power EN 300 220-1 V2.4.1 (2012-05), Subclause 7.5 ......................... 7
Modulation Bandwidth EN 300 220-1 V2.4.1 (2012-05), Subclause 7.7 ................. 9
Unwanted Emissions in Spurious Domains EN 300 220-1 V2.4.1 (2012-05),
Subclause 7.8 ............................................................................................... 12
2.3. 868 MHz wide band, 50 kbps, GFSK ................................................................ 14
Setup .......................................................................................................... 14
Average Power ETSI EN 300 220-1 V2.4.1 (2012-05), Subclause 7.2 ................. 15
Transient Power EN 300 220-1 V2.4.1 (2012-05), Subclause 7.5 ........................ 16
Modulation Bandwidth EN 300 220-1 V2.4.1 (2012-05), Subclause 7.7 ................ 18
Unwanted Emissions in Spurious Domains EN 300 220-1 V2.4.1 (2012-05),
Subclause 7.8 ............................................................................................... 21
www.onsemi.com
AND9318/D
Introduction
1.
Introduction
All measurements are executed conducted. The measurements are performed on the
AX5051 DVK2b module. It is not the aim to measure an antenna performance.
Devices are set up using the AXGen2-RadioLab software.
Identical results can be obtained for AX5151, AX5031, AX5131 and AX8052F151.
1.1. Receive
Receivers of ETSI EN 300 220-1 V2.4.1 (2012-05) Categories 2 or 3 can be built using
AX5051. Please refer to the datasheet for the relevant sensitivity and blocking values.
1.2. Transmit
The following table lists output power levels for GFSK modulated signals that can pass
ETSI EN 300 220-1 V2.4.1 (2012-05) as a function of the bitrate and the reference
crystal frequency. In the following chapters of this application note, detailed
measurements for 50 kbps GFSK using a 16 MHz crystal and 100 kbps GFSK using a 24
MHz crystal are presented.
Bitrate
Crystal frequency
Typical output level
GFSK with
h=0.67
Passes ETSI EN 300 220-1 V2.4.1
(2012-05) in the frequency band
868.0 - 868.6 MHz
(wide band)
50 kbps
14 dBm
100 kbps
16 MHz
8 dBm
200 kbps
5 dBm
100 kbps
14 dBm
200 kbps
300 kbps
24 MHz
12 dBm
7 dBm
Table 1 : Typical output power levels for GFSK, h=0.67 modulated signals that can pass ETSI EN 300
220-1 V2.4.1 (2012-05) in the frequency band 868.0 – 868.6 MHz (wide band).
www.onsemi.com
AND9318/D
3
4
Measurements
2.
Measurements
2.1. General
Frequency Error
ETSI EN 300 220-1 V2.4.1 (2012-05), Sub-clause 7.1
The frequency error of the AX5051 is given by the frequency error of the frequency
source XTAL or TCXO.
ETSI EN 300 220-1 requirements are
+/- 100 ppm for 868 MHz wide band systems,
+/- 14.4 ppm for 868 MHz narrow band systems,
+/- 27 ppm for 433 MHz narrow band systems,
+/- 59 ppm for 169 MHZ narrow band systems.
Narrow band refers to channel widths smaller  25 kHz.
EN 13 757-4 2005 which applies for wireless M-Bus devices, requires stricter frequency
errors. 60 or 25 ppm for the center frequency.
Although this is all achievable with normal crystals, we do recommend use of a TCXO for
optimal performance in narrow band systems.
www.onsemi.com
AND9318/D
Measurements
2.2. 868 MHz wide band, 100 kbps, GFSK
ETSI EN 300 220-1 V2.4.1 (2012-05), in frequency band 868.0 - 868.6 MHz.
Setup
Module
AX5051 DVK-2b V1.4 Module with 24 MHz
XTAL
Internal synthesizer loop filter
Measurement equipment
0.5 m RG-58 cable from SMA to R&S FSEB
spectrum analyzer (note 1)
Mainboard and debug adapter
DVK-2
Setup software
AXGen2-RadioLab V1.1
Carrier Frequency
868.3 MHz
Bit rate
100 kbps
Modulation
GFSK
FSK deviation (fmark-fspace)/2
h=0.667, 33.334 kHz
Changes to setup software default register
settings
Set the parameter “Radio XTAL prestart
time” in the Synchronous Timing Panel to
1.56 ms.
Changes to hardware default configuration
1. Use 24 MHz XTAL
2. Remove 100 nF capacitor from pin 26
Power level for which module meets ETSI
EN 300 220-1 V2.4.1 (2012-05)
14 dBm (note 1 & 2)
Table 2: Setup for 868.3 MHz, 100kbps, GFSK
Notes:
1. Values presented are the spectrum analyzer readings. Cable losses are not
compensated
2. The maximum power level for 868.3 MHz is 14 dB. The maximum power level of
AX5051 is above the limit but can be programmed down to meet the limit. The Power
level of AX5051 is very little dependent on supply voltage.
www.onsemi.com
AND9318/D
5
6
Measurements
Average Power
ETSI EN 300 220-1 V2.4.1 (2012-05), Subclause 7.2
AX5051 is outputting CW for this measurement. The ETSI limit for the 868.0 – 868.6
MHz band is 25 mW (14 dBm). Measured output for AX5051 is 13.8 dBm, all the
following measurements were done at this power level.
Figure 1: Transmit spectrum, 868.3 MHz, CW
www.onsemi.com
AND9318/D
Measurements
Transient Power
EN 300 220-1 V2.4.1 (2012-05), Subclause 7.5
The edges of the modulation bandwidth are fa = 868.44 MHz and fb = 868.16 MHz, see
Figure 5. The following figures show measured Transient Power maximum levels for both
On-Off operating mode (ETSI Step 1) and continuous operating mode (ETSI Step 2).
Detector setting max
ETSI limits are either –36 dBm for On-Off operating mode or where this is not met, no
more than 3 dB difference between Step 1 and Step 2 measurements. It can be seen
from Figure 3 and Figure 4, that this is met.
Note that crystals can vary in the start-up time required. If there are overshoots at the
rising edge of the on-off operation then this is an indicator of a too short XTAL start-up
time. In the RadioLab software this parameter can be set in the Synchronous Timing
Panel in the field “Radio XTAL prestart time”. That setting varies the XTAL start-up time
for all duty-cycled modes, not only for synchronous timing!
Figure 2: Measurement for transient power at 240 kHz distance from the carrier frequency. The blue
trace shows results for on-off operation (step 1), the green trace shows the reference
measurement results for continuous transmission (step 2). Note that detector setting max peak is
used.
www.onsemi.com
AND9318/D
7
Measurements
maximum power with max peak detector [dBm]
-5
Step 2: Continuous
-10
Step 1: On-Off
-15
-20
-25
-30
-35
-40
-45
-2000
-1500
-1000
-500
0
500
1000
1500
2000
offset from carrier [kHz]
Figure 3: Measurement of transient power for frequency offsets fa +100 kHz and fb - 100 kHz to +/2 MHz offset from carrier. Note that detector setting max peak is used.
3
On-Off max power - Continuous max power [dB]
8
2
1
0
-1
-2
-3
-2000
-1500
-1000
-500
0
500
1000
1500
2000
offset from carrier [kHz]
Figure 4: Difference between transient power measurements step 1 and step 2. Note that detector
setting max peak is used.
www.onsemi.com
AND9318/D
Measurements
Modulation Bandwidth
EN 300 220-1 V2.4.1 (2012-05), Subclause 7.7
The following three plots show the modulated output at different resolution bandwidths
with the corresponding ETSI limit lines.
Spectrum analyzer settings for all three measurements are:


detector function: max peak
trace: max hold
Figure 5: Transmit spectrum, 868.3 MHz, GFSK, 100 kbps, h=0.667, RBW=1 kHz, detector max
peak, trace max hold
www.onsemi.com
AND9318/D
9
10
Measurements
Figure 6: Transmit spectrum, 868.3 MHz, GFSK, 100 kbps, h=0.667, RBW=10 kHz, detector max
peak, trace max hold
www.onsemi.com
AND9318/D
Measurements
Figure 7: Transmit spectrum, 868.3 MHz, GFSK, 100 kbps, h=0.667, RBW=100 kHz, detector max
peak, trace max hold
www.onsemi.com
AND9318/D
11
12
Measurements
Unwanted Emissions in Spurious Domains
EN 300 220-1 V2.4.1 (2012-05), Subclause 7.8
Unwanted emissions are shown for the most critical cases.
470 – 862 MHZ
From 470 – 862 MHz the ETSI limit is –54 dBm for an RBW of 100 kHz. The highest
measured spur is –60.7 dBm.
Figure 8: Spurious emission 470 – 862 MHz
www.onsemi.com
AND9318/D
Measurements
HARMONICS
Above 1 GHz the ETSI limit is –30 dBm for an RBW of 1 MHz. Here the harmonics of the
wanted signal are most critical, but below –36 dBm.
Spectrum analyzer settings for all three measurements are:


detector function: max peak
trace: max hold
Figure 9: Spurious emission above 1 GHz, detector max peak, trace max hold
www.onsemi.com
AND9318/D
13
14
Measurements
2.3. 868 MHz wide band, 50 kbps, GFSK
ETSI EN 300 220-1 V2.4.1 (2012-05) in frequency band 868.0 - 868.6 MHz.
Setup
Module
AX5051 DVK-2b V1.4 Module with 16 MHz
XTAL
Internal synthesizer loop filter
Measurement equipment
0.5 m RG-58 cable from SMA to R&S FSEB
spectrum analyzer (note 1)
Mainboard and debug adapter
DVK-2
Setup software
AXGen2-RadioLab V1.1
Carrier Frequency
868.3 MHz
Bit rate
50 kbps
Modulation
GFSK
FSK deviation (fmark-fspace)/2
h=0.667, 16.667 kHz
Changes to setup software default register
settings
Set the parameter “Radio XTAL prestart
time” in the Synchronous Timing Panel to
1.56 ms.
Changes to hardware default configuration
Remove 100 nF capacitor from pin 26
Power level for which module meets ETSI
EN 300 220-1 V2.4.1 (2012-05)
14 dBm (note 1 & 2)
Table 3: Setup for 868.3 MHz, 100kbps, GFSK
Notes:
1. Values presented are the spectrum analyzer readings. Cable losses are not
compensated
2. The maximum power level for 868.3 MHz is 14 dB. The maximum power level of
AX5051 is above the limit but can be programmed down to meet the limit. The Power
level of AX5051 is very little dependent on supply voltage.
www.onsemi.com
AND9318/D
Measurements
Average Power
ETSI EN 300 220-1 V2.4.1 (2012-05), Subclause 7.2
AX5051 is outputting CW for this measurement. The ETSI limit for the 868.0 – 868.6
MHz band is 25 mW (14 dBm). Measured output for AX5051 is 13.8 dBm, all the
following measurements were done at this power level.
Figure 10: Transmit spectrum, 868.3 MHz, CW
www.onsemi.com
AND9318/D
15
16
Measurements
Transient Power
EN 300 220-1 V2.4.1 (2012-05), Subclause 7.5
The edges of the modulation bandwidth are f a = 868.4 MHz and fb = 868.2 MHz, see
Figure 13. The following figures show measured Transient Power maximum levels for
both On-Off operating mode (ETSI Step 1) and continuous operating mode (ETSI Step
2). Detector setting max
ETSI limits are either –36 dBm for On-Off operating mode or where this is not met, no
more than 3 dB difference between Step 1 and Step 2 measurements. It can be seen
from Figure 11 and Figure 12, that this is met.
For further remarks and a spectrum analyzer picture illustrating the measurement setup
see the chapter on transient power for 100 kbps GFSK.
www.onsemi.com
AND9318/D
Measurements
maximum power with peak detector [dBm]
0
-5
Step 2: Continuous
Step 1: On-Off
-10
-15
-20
-25
-30
-35
-40
-45
-2000
-1500
-1000
-500
0
500
1000
1500
2000
offset from carrier [kHz]
Figure 11: Measurement of transient power for frequency offsets fa +100 kHz and fb - 100 kHz to
+/- 2 MHz offset from carrier. Note that detector setting max peak is used.
On-Off max power - Continuous max power [dB]
3
2
1
0
-1
-2
-3
-2000
-1500
-1000
-500
0
500
1000
1500
2000
offset from carrier [kHz]
Figure 12: Difference between transient power measurements step 1 and step 2. Note that detector
setting max peak is used.
www.onsemi.com
AND9318/D
17
18
Measurements
Modulation Bandwidth
EN 300 220-1 V2.4.1 (2012-05), Subclause 7.7
The following three plots show the modulated output at different resolution bandwidths
with the corresponding ETSI limit lines.
Spectrum analyzer settings for all three measurements are:


detector function: max peak
trace: max hold
Figure 13: Transmit spectrum, 868.3 MHz, GFSK, 50 kbps, h=0.667, RBW=1 kHz, detector max
peak, trace max hold
www.onsemi.com
AND9318/D
Measurements
Figure 14: Transmit spectrum, 868.3 MHz, GFSK, 50 kbps, h=0.667, RBW=10 kHz, detector max
peak, trace max hold
www.onsemi.com
AND9318/D
19
20
Measurements
Figure 15: Transmit spectrum, 868.3 MHz, GFSK, 50 kbps, h=0.667, RBW=50 kHz, detector max
peak, trace max hold
www.onsemi.com
AND9318/D
Measurements
Unwanted Emissions in Spurious Domains
EN 300 220-1 V2.4.1 (2012-05), Subclause 7.8
Unwanted emissions are shown for the most critical cases.
470 – 862 MHZ
From 470 – 862 MHz the ETSI limit is –54 dBm for an RBW of 100 kHz. The highest
measured spur is –64.9 dBm.
Figure 16: Spurious emission 470 – 862 MHz
www.onsemi.com
AND9318/D
21
22
Measurements
HARMONICS
Above 1 GHz the ETSI limit is –30 dBm for an RBW of 1 MHz. Here the harmonics of the
wanted signal are most critical, but below –35 dBm.
Spectrum analyzer settings for all three measurements are:


detector function: max peak
trace: max hold
Figure 17: Spurious emission above 1 GHz, detector max peak, trace max hold
www.onsemi.com
AND9318/D
23
www.onsemi.com
AND9318/D
Similar pages