AN805: Si446x Wireless MBUS Receiver

This application note describes how to create a wireless MBUS-compliant device using

Silicon Labs Si4461/63/64 cost-efficient, high-performance EZRadioPRO

RF trans-

ceiver and EZR32 wireless MCU family. It does not cover the duty cycle and other tim-

ing requirements of the standard; rather, it focuses on the RF-related requirements of

the prEN 13757-4 rev:2013 wireless MBUS standard, unless noted otherwise. The RF

measurements listed in this application note were performed on the 4461-868-PDK de-

velopment kit using the Wireless Development Suite. Refer to 2.6 Radio Link Require-

ments for Mode F for more details.

KEY POINTS

• Silicon Labs Si446x high-performance RF

transceivers support all the WMBUS

modes, including S, T, R, C, F and various

N modes

•

The EZRadioPRO

transceivers meet

WMBUS specifications

silabs.com | Smart. Connected. Energy-friendly. Rev. 0.3

1. Summary

Table 1.1 Measured Sensitivity for 80% PER on page 1 summarizes the measured sensitivity for 80% PER and indicates that the

radio meets the given MBUS mode specification.

Table 1.1. Measured Sensitivity for 80% PER

Mode Parameter Measurement Results Comment

1 S1,S2 Sensitivity –110 dBm Meets MBUS Specifica-

tions

freq. offset, data rate, |

deviation corners

Meets all Corners

2 T1, T2 Sensitivity –106 dBm Meets MBUS Specifica-

tions

freq. offset, data rate, de-

viation corners

Meets all Corners

3 R2 Sensitivity –117 dBm Meets MBUS Specifica-

tions

freq. offset, data rate, de-

viation corners

Meets all Corners

4 C Sensitivity –110 dBm

(Meter to other)

-113 dBm

(Other to meter)

Meets MBUS Specifica-

tions

freq. offset, data rate, de-

viation corners

Meets All Corners

5 N(1,2)

a/b/e/f

Sensitivity –122 dBm Meets MBUS Specifica-

tions

1 , 2

freq. offset, data rate, de-

viation corners

Meets All Corners

6 N(1,2)

c/d

Sensitivity –120.5 dBm Meets MBUS Specifica-

tions

freq. offset, data rate, de-

viation corners

Meets all Corners

7 Sensitivity –113 dBm Meets MBUS Specifica-

tions

N2g freq. offset, data rate, de-

viation corners

Meets all corners

8 F Sensitivity –117 dBm Meets MBUS Specifica-

tions

freq. offset, data rate, de-

viation corners

Meets all corners with

longer wake-up window

Note:

1. 2.4 kHz deviation is used for the measurement according to the prEN 13757-4:2013 draft version of the standard.

2. The deviation offset tolerances were measured according to the prEN 13757-4:2013 draft version of the standard.

AN805: Si446x Wireless MBUS Receiver

Summary

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2. Wireless MBUS Standard

The Wireless MBUS standard (EN 13757-4) specifies two kinds of devices: “Meters” and “Others” (mobile readout devices, data collec-

tors, etc.). The standard also defines several types of communication between devices:

• Mode S ("Stationary mode"):

• Mode S1: unidirectional link from the Meter to the Other device

• Mode S1m: unidirectional link from the Meter to the Other device

• Mode S2: bidirectional communication between the Meter and Other device

• Mode T ("Frequent transmit mode"):

• Mode T1: unidirectional link from the Meter to the Other device

• Mode T2: bidirectional link from the Meter to the Other device

• Mode R ("Frequent receive mode"): special, multipchannel receiving mode

• Mode R2: bidirectional link from Meter to Other device

• Mode C ("Compact Mode"):

• Mode C1: unidirectional link from the Meter to the Other device

• Mode C2: bidirectional link from the Meter to the Other device

• Mode N ("Narrowband VHF Mode"):

• Mode N1a-g: unidirectional link from the Meter to the Other device

• Mode N2a-g: bidirectional link from the Meter to the Other device

• Mode F: protocol using routers

The following tables list the radio requirements for the transmitter and receiver for Mode S, T, R, C, N, and F devices.

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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2.1 Radio Link Requirements for Mode S

Table 2.1. Transmitter Requirements for Mode S

Characteristic Mode Sym Min Typ Max Unit Note

Center Fre-

quency

(Transmit Only

Meter, S1-Sub-

Mode)

868.25 868.30 868.35 MHz ~ 60 x 10 – 6

(ppm)

Center Fre-

quency

(Other and S2-

Mode)

868.278 868.300 868.322 MHz ~ 25 x 10 – 6

(ppm)

FSK Deviation ±40 ±50 ±80 kHz

Chip Rate

Transmit

chip

— 32.768 — kcps

Chip Rate Tol-

erance

— — ±1.5 %

Digital Bit Jit-

ter

— — ±3 µs

Data Rate

(Manchester)

— f

chip

× 1/2 — bps

Preamble

Length Includ-

ing Bit/ Byte

Sync,

Both Directions

S2,

S1-M

— —

chips

Preamble

Length Includ-

ing Bit/byte

Sync

S1 PL 576

— —

chips

Optional for S2

Postamble

(Trailer)

Length

2 — 8 chips

Response De-

lay

(Other To Me-

ter Communi-

cation)

3 — 50 ms

FAC Transmis-

sion Delay

5 , 6

S2 t

TxD

N × 1000 – 0.5 N × 1000 N × 1000 + 0.5 ms N = 2,3,4,or 5

FAC Time Out

S2 t

25 — 30 s

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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Characteristic Mode Sym Min Typ Max Unit Note

Note:

1. The bit jitter shall be measured at the output of the microcontroller or encoder circuit.

2. Each bit shall be coded as two chips (Manchester encoding).

3. The postamble (trailer) shall consist of n = 1 to 4 “ones”, i.e., the chip sequence is n x (01).

4. Response delay: After transmitting a frame in S2-mode, the receiver shall be ready for the reception of a response in a time

shorter than the minimum response delay and shall be receiving at least for the duration of the maximum response delay.

5. FAC Transmission delay describes the time by which a meter shall delay the first response to a received message from another

device referred to in its last transmission. This delay shall also be applied between the first response of the meter and the next

repeated response of the meter and all following repeated responses during the Frequent Access Cycle (FAC). The reference

time point shall be the end of preamble (end of sync sequence) of the meter transmission. For timing diagrams, see Appendix E.

6. The selected timeslot, N, shall be the same throughout the Frequent Access Cycle.

7. FAC Time out: is the time period between the last successful reception of a frame from the Other Device during the Frequent

Access Cycle (FAC) and the moment where the repetition of the last response of the Meter shall be stopped (end of Frequent

Access Cycle).

Table 2.2. Receiver Requirements for Mode S

Characteristic Class Sym Min Typ Max Unit

Sensitivity (BER

< 10

) or (PER <

0.8)

–100 –105 — dBm

Blocking Per-

formance

3 — — Category

Blocking Per-

formance

2, 3

2 — — Category

Blocking Per-

formance

23, 4

2 — — Category

Acceptable Chip

Rate Tolerance

fchip

— — ± 2 %

Chip rate (Meter) f

chip

— 32,768 — kcps

Note:

1. At a frame size of 20 bytes.

2. Receiver category according to ETSI En 300 220-1, V2, 4, 1:2012, 4.1.1.

3. Additional requirement for class MR and class HR receivers: The equipment shall meet the immunity requirements as specified in

ETSI EN 301 489-1, V1.9.2: 2011, 9.2.

4. Additional requiremen for class HR receivers: Adjacent band selectivity shall be 40 dB when measured according to ETSI EN 300

220-1, v2.4.1: 2012, 8.3.

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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2.2 Radio Link Requirements for Mode T

Table 2.3. Transmitter Requirements for Mode T

Characteristic Mode Sym Min Typ Max Unit Note

Center Fre-

quency (Meter

to Other)

T1,T2 868.90 868.95 869.00 MHz ~ 60 x 10 – 6

(ppm)

Center Fre-

quency (Other

to Meter)

T2 868.278 868.300 868.322 MHz ~ 25 x 10 – 6

(ppm)

FSK Deviation

(Meter to Oth-

er)

T1,T2 ±40 ±50 ±80 kHz

FSK Deviation

(Other to Me-

ter)

T2 ±40 ±50 ±80 kHz

Chip Rate

Transmit (Me-

ter to Other)

T1,T2 f

chip

90 100 110 kcps

Rate Variation

within Header

+ Frame (Me-

ter)

T1,T2 D

fchip

— 0 ±1 %

Data Rate

(Meter to Oth-

er, 3 out of 6

Encoding)

T1,T2 — f

chip

× 2/3 — bps

Chip Rate

Transmit (Oth-

er to Meter)

T2 — 32.768 — kcps

Chip Rate Tol-

erance

(Other to Me-

ter)

T2 — — ±1.5 %

Digital Bit Jit-

ter

T2 — — ±3 us

Data Rate

(Other to Me-

ter, Manches-

ter)

T2 — f

chip

× 1/2 — bps

Preamble

Length Includ-

ing Bit / Byte

Sync

Both Directions

T1,T2 PL 48 — — chips

Postamble

(Trailer)

Length

T1,T2 2 — 8 chips

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Wireless MBUS Standard

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Characteristic Mode Sym Min Typ Max Unit Note

Response De-

lay

(Other to Meter

Communica-

tion)

T2 t

2 — 3 ms

FAC Transmis-

sion Delay

5 , 6

T2 t

TxD

N×1000 – 0.5 N×1000 N×1000 + 0.5 ms N = 2,3,4, or 5

FAC Time Out

T2 t

25 — 30 s

Note:

1. Each nibble (4 bits) shall be coded as six chips.

2. The bit jitter shall be measured at the output of the microprocessor or encoder circuit.

3. The postamble (trailer) shall consist of at least of at least two alternating chips. If the last chip of the CRC was a zero, then the

minimum postamble shall be “10”; otherwise, it shall be “01”.

4. Response delay: after transmitting a frame including the postamble, the receiver shall be ready for the reception of a response in

a time shorter that the minimum response delay. After transmitting a frame, the receiver shall listen for a possible response for at

least the maximum response delay.

5. FAC Transmission delay describes the time by which a meter shall delay the first response to a received message from another

received message from another device referred to in its last transmission. This delay shall also be applied between the first re-

sponse of the meter and the next repeated response of the meter and all following repeated responses during the Frequent Ac-

cess Cycle (FAC). The reference time point shall be the end of preamble (end of sync sequence) of the meter transmission.

6. The selected timeslot, N, shall be the same throughout the Frequent Access Cycle.

7. FAC Time out is the time period between the last successful reception of a frame from the other device during the Frequent Ac-

cess Cycle (FAC) and the moment when the repetition of the last response of the meter shall be stopped (end of Frequent Ac-

cess Cycle).

Table 2.4. Receiver Requirements for Mode T

Characteristic Class Sym Min Typ Max Unit Note

Sensitivity

(BER < 10

–2

)

or (PER <

0,8)

–100 –105 — dBm

Blocking Per-

formance

— 3 — Category

Blocking Per-

formance

2, 3

— 2 — Category

Blocking Per-

formance

23, 4

— 2 — Category

Acceptable

Header Chip

Rate Range:

(Other)

T1,T2 f

chip

88 100 112 kcps ~± 12%

Acceptable

Chip Rate Var-

iation During

Header and

Frame: (Other)

T1,T2 D

fchip

— 0 ±2 %

Acceptable

Chip Rate Tol-

erance

T2 D

fchip

— ±2 %

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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Characteristic Class Sym Min Typ Max Unit Note

Chip Rate

(Meter)

T2 f

chip

— 32,768 — kcps

Acceptable

chip rate toler-

ance (meter)

T2 Dfchip2 — 0 ±2 % —

Note:

1. At a frame size of 20 bytes.

2. Receiver category according to ETSI EN 300 220-1, V2.4.1:2012, 4.1.1.

3. Additional requirement for class MR and class HR receivers: The equipment shall meet the immunity requirements as specified in

ETSI EN 301 489-1, V1.9.2: 2011, 9.2.

4. Additional requirement for class HR receivers: Adjacent band selectivity shall be \>40 dB when measured according to ETSI EN

300 220-1, V2.4.1: 2012, 8.3.

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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2.3 Radio Link Requirements for Mode R2

Table 2.5. Transmitter Requirements for Mode R2

Characteristic Mode Sym Min Typ Max Unit Note

Center Fre-

quency (Other)

— 868.33 — MHz

Center Fre-

quency (Meter)

— 868.030 + n x

0.06

— MHz

Frequency Tol-

erance (Meter/

Other)

— 0 ±17 ~ 20 x 10 – 6

(ppm)

FSK Deviation ±4.8 ±6 ±7.2 kHz

Chip Rate

(Wakeup and

Communica-

tions)

chip

— 4.8 kcps

Chip rate Tol-

erance

(Wakeup and

Communica-

tions

— — ±1.5 %

Digital Bit Jit-

ter

— — ±15 us

Data rate

(Manchester)

— f

chip

× 1/2 — bps

Preamble

Length Includ-

ing Bit / Byte

Sync

PL 96 — — chips

Postamble

(Trailer)

Length

2 — 8 chips

Response De-

lay

(Other to

Meter Commu-

nication)

3 — 50 ms

Response De-

lay

(Meter to

Other Commu-

nication)

10 — 10000 ms

FAC Transmis-

sion Delay

5, 6

R2 t

TxD

N×1000 – 1 N×1000 N × 1000 + 1 ms N=12,13,14, or

FAC Time Out

R2 t

25 — 30 s

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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Characteristic Mode Sym Min Typ Max Unit Note

Note:

1. The bit jitter shall be measured at the output of the micro-controller or encoder circuit.

2. Each bit shall be coded as two chips (Manchester encoding).

3. The postamble (trailer) shall consist of n = 1 to 4 “ones”, i.e., the chip sequence is n x (01).

4. Response delay: after transmitting a frame, the receiver shall be ready for the reception of a response in a time shorter than the

minimum response delay and shall receive at least for the duration of the maximum response delay.

5. FAC Transmission delay describes the time by which a meter shall delay the first response to a received message from another

device referring to its last transmission. This delay shall also be applied between the first response of the meter and the next

repeated response of the meter and all following repeated responses during the Frequent Access Cycle (FAC). The reference

time point shall be the end of preamble (end of sync sequence) of the meter transmission.

6. The selected timeslot, N, shall be the same throughout the Frequent Access Cycle.

7. FAC Time out is the time period between the last successful reception of a frame from the other device during the Frequent Ac-

cess Cycle (FAC) and the moment where the repetition of the last response of the meter shall be stopped (end of Frequent Ac-

cess Cycle).

Table 2.6. Receiver Requirements for Mode R2

Characteristic Class Sym Min Typ Max Unit Note

Sensitivity

(BER < 10Ù–2)

or (PER <

0,8)

–105 –110 — dBm

Blocking per-

formance

— 3 — Category

Blocking per-

formance

2,3

— 2 — Category

Blocking per-

formance

2,3,4

— 2 — Category

Acceptable

Chip rate varia-

tion during

header and

frame

fchip

— — ±0.2 %

Acceptable

chip rate range

chip

4.7 4.8 4.9 kcps ~ ±2%

Note:

1. At a frame size of 20 bytes.

2. Receiver category according to ETSI EN 300 220-1, V2.4.1:2012, 4.1.1.

3. Additional requirement for class MR and class HR receivers: The equipment shall meet the immunity requirements as specified in

ETSI EN 301 489-1, V1.9.2: 2011, 9.2.

4. Additional requirement for class HR receivers: Adjacent band selectivity shall be \>40 dB when measured according to ETSI EN

300 220-1, V2.4.1: 2012, 8.3.

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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2.4 Radio Link Requirements for Mode C

Table 2.7. Transmitter Requirements for Mode C

Characteristic Mode Sym Min Typ Max Unit Note

Center Fre-

quency

(Meter to Oth-

er)

C1,C2 868.928 868.95 868.972 MHz ~ 25 x 10-6

(ppm)

Centre Fre-

quency (Other

to Meter)

C2 869.503 869.525 869.547 MHz ~ 25 x 10-6

(ppm)

FSK Deviation

(Meter to Oth-

er)

C1,C2 ±43 ±45 ±47 kHz

GFSK Devia-

tion (Other to

Meter)

C2 ±23 ±25 ±27 kHz

GFSK Relative

Bandwidth

C2 BT — 0.5 —

Chip Rate

(Meter to Oth-

er)

C1,C2 f

chip

— 100 — kcps

Chip Rate

(Other to Me-

ter)

C2 f

chip

— 50 — kcps

Chip Rate Tol-

erance

C1,C2 D

fchip

— — 100 ppm

Data Rate

C1,C2 — f

chip

— bps

Preamble

Length

C1,C2 PL — 32 — chips

Synchroniza-

tion Length

C1,C2 SL — 32 — chips

Fast Response

Delay

2, 3, 4

C2 t

90 — 91 ms

Slow Re-

sponse Delay

2, 3, 4

(Other to Meter

Communica-

tion)

C2 t

RO_slow

1000 — 1001 ms

Fast Response

Delay (De-

fault)

2, 3

(Meter to Other

Communica-

tion)

C2 t

90 — 91 ms

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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Characteristic Mode Sym Min Typ Max Unit Note

Slow Re-

sponse Delay

(Meter to Other

Communica-

tion)

C2 t

RM_slow

1000 — 1001 ms

FAC Transmis-

sion Delay

5, 6

C2 t

TxD

N×1000 – 0,5 N×1000 N×1000 + 0,5 ms N=2,3,4 or 5

FAC Time Out

C2 t

25 — 30 s

Note:

1. All bits are NRZ coded.

2. Response delay: after transmitting a frame including the postamble, the receiver shall be ready for the reception of a response in

a time shorter than the minimum response delay. After transmitting a frame, the receiver shall listen for a possible response for at

least a maximum response delay.

3. The use of slow or fast response delay is specified in the “Communication Control Field” of the extended link layer. If an extended

link layer is not included in the frame, the default response delay shall be used.

4. If the frame is repeated, the other end shall instead use a shorter response delay (tRR or tRR_slow) being 75 ms shorter than the

corresponding tRO or tRO_slow. This enables bidirectional communication to be repeated without loss of communication speed.

The frame from meter to other shall be repeated with a delay of less than 5 ms (tDR).

5. FAC Transmission delay describes the time by which a meter shall delay the first response to a received message from another

device referring to its last transmission. This delay shall also be applied between the first response of the meter and the next

repeated response of the meter and all following repeated responses during the Frequent Access Cycle (FAC). The reference

time point shall be the end of preamble (end of sync sequence) of the meter transmission.

6. The selected timeslot, N, shall be the same throughout the Frequent Access Cycle.

7. FAC Time out is the time period between the last successful reception of a frame from the other device during the Frequent Ac-

cess Cycle (FAC) and the moment when the repetition of the last response of the meter shall be stopped (end of Frequent Ac-

cess Cycle).

Table 2.8. Receiver Requirements for Mode C

Characteristic Class Sym Min Typ Max Unit Note

Sensitivity

(BER < 10

–2

)

or (PER < 0. 8)

(Other Device)

–100 –105 — dBm

Sensitivity

(BER < 10

–2

)

or (PER < 0. 8)

(Meter)

— –95 — dBm

Blocking Per-

formances

2, 3,

— 2 — Category

Note:

1. At a frame size of 20 bytes.

2. Receiver category according to ETSI EN 300 220-1, V2.4.1:2012, 4.1.1.

3. Additional requirement for class MR and class HR receivers: The equipment shall meet the immunity requirements as specified in

ETSI EN 301 489-1, V1.9.2: 2011, 9.2.

4. Additional requirement for class HR receivers: Adjacent band selectivity shall be \>40 dB when measured according to ETSI EN

300 220-1, V2.4.1: 2012, 8.3.

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Wireless MBUS Standard

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2.5 Radio Link Requirements for Mode N

Table 2.9. Link Parameters for Mode N

Mode

Channel

1 , 2

Center Frequen-

cy (MHz)

Channel Spac-

ing (kHz)

GFSK (kbps) 4GMSK (kbps) Frequency Tol-

erance (± kHz)

N1a, N2a

1a 169,406,250 12,5 4,8 1,5

N1b, N2b

1b 169,418,750 12,5 4,8 1,5

N1c, N2c 2a 169,431,250 12,5 2,4 2,0

N1d, N2d 2b 169,443,750 12,5 2,4 2,0

N1a, N2a

3a 169,456,250 12,5 4,8 1,5

N1b, N2b

3b 169,468,750 12,5 4,8 1,5

N2g

169,437,500 50 19,2 2,5

a 1 169,412,500 25

a 2 169,437,500 25

a 3 169,462,500 25

Note:

1. These channels are optional and reserved for future use or national specific use.

2. Channel designation according to EU commission decision 2005/928/EC.

3. 2.4 kHz deviation is used for the measurement according to the prEN 13757-4:2013 draft version of the standard.

4. This channel may be used for multi-hop transmission of meter data as specified in EN 13757-5. The duty cycle for transmission

from the meter shall be limited to 0.02% in this channel.

Table 2.10. Mode N, Modulation and Timing

Characteristic Data Rate Sym Min Typ Max Unit Note

GFSK Modula-

tion (modula-

tion index 2.0)

2,4 kbps ± 1.68 ± 2.4 ± 3.12 kHz 70-130 % of

nominal devia-

tion

GFSK Modula-

tion (modula-

tion index 1.0)

4.8 kbps ± 1.68 ± 2.4 ± 3.12 kHz 70-130 % of

nominal devia-

tion

4GFSK Modu-

lation (modula-

tion index 0.5)

19.2 kbps –7.2, –2.4,

+2.4, +7.2

kHz

4GFSK peak

modulation

19.2 kbps ± 5.04 ± 9.36 kHz 70-130 % of

nominal devia-

tion

GFSK/4GFSK

relative band-

width

All BT 0.5

Bit/symbol rate

tolerance

All ± 100 ppm

Preamble

length

All PL 16 16 bits or sym-

bols

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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Characteristic Data Rate Sym Min Typ Max Unit Note

Synchronisa-

tion length

All SL 16 16 bits or sym-

bols

Postamble

(trailer) length

All 0 bits or sym-

bols

Fast response

delay

(Other

Device to Me-

ter)

All t

99.5 100 100.5 ms

Slow response

delay

(Other

Device to Me-

ter)

2.4 kbps 4.8

kbps 19.2 kbps

RO_slow

2 099,5 1

099,5 1 099,5

2 100,5 1

100,5 1 100,5

FAC transmis-

sion delay (N2a

to N2f)

3, 4

2.4 kbps 4.8

kbps

TxD

N×1 000 –0.5 N×1 000 N×1 000+0.5 ms N=5,7 or 13

FAC transmis-

sion delay (N2g

only)

3, 4

19.2 kbps t

TxD

N×1 000 –0.5 N×1 000 N×1 000+0.5 ms N= 2,3 or 5

FAC time out

All tTO 25 30 s

Note:

1. Measured in centre of outer symbol (frequency vs. time eye opening) transmitting PN9 sequence, min./max. based on rms error

value.

2. The transmitter shall start transmitting the preamble within this time delay after last bit of received frame. The use of slow or fast

response delay is specified in the “Communication Control Field” of the Extended Link Layer – refer to 12.2.2.3. For timing dia-

grams see Annex E. If an Extended Link Layer is not included in the frame, the default response delay shall be used.

3. FAC Transmission delay: describes the duration which a Meter shall delay the first response to a received message from an Oth-

er Device referred to its last transmission. This delay shall also be applied between the first response of the Meter and the next

repeated response of the Meter and all following repeated responses during the Frequent Access Cycle (FAC). The reference

time point shall be the end of preamble (end of sync sequence) of the Meter transmission.

4. The selected timeslot N shall be the same throughout the Frequent Access Cycle.

5. FAC Time out: is the time period between the last successful reception of a frame from the Other Device during the Frequent

Access Cycle (FAC) and the moment where the repetition of the last response of the Meter shall be stopped (end of Frequent

Access Cycle).

Table 2.11. Mode N, Receiver

Characteris-

tic

Class Sym Min Typ Max Unit Note

Sensitivity

(BER <10

-2

) or

(PER <0.8)

(Other De-

vice /Meter)

GFSK

–115 –123 dBm 2.4 kbps

Sensitivity

(BER <10

-2

) or

(PER <0.8)

(Other De-

vice /Meter)

GFSK

–112 –120 dBm 4.8 kbps

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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Characteris-

tic

Class Sym Min Typ Max Unit Note

Sensitivity

(BER <10

-2

) or

(PER <0.8)

(Other De-

vice /Meter)

4GFSK

–104 –107 dBm 19.2 kbps

Blocking Per-

formance

3 Category

Blocking Per-

formance

2, 3

2 Category

Blocking Per-

formance

2, 3, 4

2 Category

Note:

1. At a frame size of 20 bytes.

2. Receiver category according to ETSI EN 300 220-1, V2.4.1:2012; 4.1.1.

3. Additional requirements for Class MR and Class HR receivers: The equipment shall meet the immunity requirements as specified

in ETSI EN 301 489-1, V1.9.2:2011, 9.2.

4. Additional requirement for Class HR receivers: Adjacent band selectivity shall be > 40 dB when measured according to ETSI EN

300 220-1, V2.4.1:2012, 8.3.

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Wireless MBUS Standard

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2.6 Radio Link Requirements for Mode F

Table 2.12. Mode F, Transmitter Parameters

Characteristic Sym Mode Min Typ Max Unit Note

Centre fre-

quency

All 433,813 433,82 433,827 MHz 16 ppm

FSK Deviation

F2, F2-m ±4.8 ±5.5 ±7.0 kHz

Data rate F2, F2-m 2,4 kcps

Data rate toler-

ance

All ±100 ppm

Response de-

lay (Meter to

Other Device)

F2-m 3 50 4 000 ms

Fast response

delay (Other

Device to Me-

ter)

c d

F2 99.5 100 100.5 ms

Slow response

delay (Other

Device to Me-

ter)

c d

RO_slow

F2 999.5 1 000 1 000.5 ms

FAC transmis-

sion delay

e f

TxD

F2 Nx1 000 Nx1 000 Nx1 000 ms N=5,7 or 13

–0.5 +0.5

FAC time out

F2 25 30 s

Note:

75–125% of nominal deviation measured in centre of chip (frequency vs. time eye opening) transmitting a 9 bit pseudo-random

(PN9) sequence, min/max based on the root-mean-square (rms) error value selected.

The time a Meter shall delay the response to a required message from an Other Device.

After receiving a frame the responding unit shall start the transmission of preamble after the specified response delay. The response

delay is measured from the reception time of the last bit of the frame. For timing diagrams see Annex E.

The use of slow or fast response delay is specified in the “Communication Control Field” of the Extended Link Layer—refer to

12.2.2.3. For timing diagrams see Annex E. If an Extended Link Layer is not included in the frame, the default response delay shall be

used.

FAC Transmission delay: This delay shall be applied between the first response of the meter and the next repeated response of the

meter and all following repeated responses during the Frequent Access Cycle (FAC). The reference time point shall be the end of

preamble (end of sync sequence) of the meter transmission. For timing diagrams see Annex E.

The selected timeslot N shall be the same throughout the Frequent Access Cycle.

FAC time out: This is the time period between the last successful reception of a frame from the Other Device during the Frequent

Access Cycle (FAC) and the moment where the repetition of the last response of the Meter shall be stopped (end of Frequent Access

Cycle).

If the frame is repeated (specified in the “Communication Control Field” of the Extended Link Layer—refer to 12.2.2) the Other Device

shall instead use a shorter response delay (t

RR_slow

) being 85 ms shorter than the corresponding t

RO_slow

. This enables

bi-directional communication to be repeated without loss of communication speed. The frame from Meter to Other Device shall be

repeated with a delay less than 5 ms (t

DRF

). For timing diagrams see Annex E.

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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Table 2.13. Mode F, Receiver

Characteristic Class Sym Min Typ Max Unit Note

Sensitivity

(BER <10-2) or

(PER < 0,8)

–115 –117 dBm 2.4 kbps

Blocking per-

formance

3 Category

Blocking per-

formance

2 Category

Blocking per-

formance

2 Category

Note:

1. At a frame size of 20 bytes.

2. Receiver category according to ETSI EN 300 220-1, V2.4.1:2012; 4.1.1.

3. Additional requirements for Class MR and Class HR receivers: The equipment shall meet the immunity requirements as specified

in ETSI EN 301 489-1, V1.9.2:2011, 9.2.

4. Additional requirement for Class HR receivers: Adjacent band selectivity shall be > 40 dB when measured according to ETSI EN

300 220-1, V2.4.1:2012, 8.3.

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Standard

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3. Measurement Setup

The measurement setup contains a single signal generator capable of playing back predefined modulation patterns and various RF pico

boards for the different frequency bands to be tested.

169 MHz 4362CPRXB169

434 MHz 4362CPRXB169

868 MHz 4362CPRXB868

All the receiver tests have been performed utilizing the on-chip packet handler. Wireless Development Suite (WDS) can be used to

configure the radio for the given WMBUS modes. WDS configuration files are provided to help configure the radio for various WMBUS

modes. These modes can be open in the Radio Configuration Application. Refer to AN796: Wireless Development Suite General De-

scription and AN632: WDS User's Guide for EZRadioPRO Devices for more details regarding WDS.

Upon sync word detection, the packet handler places a predefined number of bytes into the FIFO. It also does a CRC calculation on the

payload data and compares it to the received CRC bytes located at the end of the packet. If the CRC check is successful, the chip

asserts its packet_received status bit; otherwise, it will assert the CRC_error status bit. During the measurement, a packet reception is

deemed successful if the packet_received status bit is set and is deemed unsuccessful if either the CRC_error status bit is set (corrup-

ted packet) or neither of the above two status bits are set (missed packet).

The test procedure for one packet is as follows:

1. Start receiver (only once at the beginning of the test).

2. Wait one packet length’s worth of time.

3. Fire packet on the generator.

4. Wait one packet length’s worth of time.

5. Check reception. Then go back to step #2.

Packet-related parameters:

• The preamble and sync word length are set according to the requirements of the actual MBUS mode.

• Payload length: 20 bytes

• Payload bytes: 0x0F, 0x44, 0xAE, 0x0C, 0x78, 0x56, 0x34, 0x12, 0x01, 0x07, 0x44, 0x47, 0x78, 0x0B, 0x13, 0x43, 0x65, 0x87,

0x1E, 0x6D

• CRC length: 2 bytes

• CRC polynomial: CRC-16 (IBM): X16+X15+X2+1

Note:

1. Whenever coding is required on the data, the length of the payload is adjusted accordingly.

2. In the case of Manchester coding, the payload is twice as long (40 bytes) in the air.

3. In the case of 3-out-of-6 coding, the payload is 1.5 times as long in the air (30 bytes).

4. The CRC used at the tests does not match the CRC specified in the standard. The CRC check is merely there to help qualify the

packet reception.

For each mode a PER curve, sensitivity vs. frequency offset, deviation offset and DR offset curves (where applicable) are presented in

the next sections. On the sensitivity curves the minimum sensitivity limit (taken from the standard) is drawn as a horizontal red line and

the offset limits are drawn as vertical red lines. The traces should always travel below the horizontal lines in the region bordered by the

vertical lines. Deriving the DR and deviation offset limits are straightforward from the Tx side specifications in the standard. The fre-

quency offset limits, however, deserve a few words here.

In the standard only the Tx side frequency accuracy is specified; we simply need an RX solution that can receive Tx signals with the

extreme frequency offsets. The receiver, however on its own has its own frequency inaccuracy that must also be taken into account.

Throughout the tests conducted for this application note, however, the receiver was calibrated to have close to 0 ppm frequency accu-

racy with regards to the signal generator. So in the test setup we do not have the aforementioned inaccuracy at the Rx side. The resolu-

tion to this issue is that we "place" the Rx inaccuracy to the Tx side and draw the offset limit lines at twice the specification on the Tx.

This logic assumes that the Rx has the same inaccuracy as the Tx. This assumption became a design goal when the receive configura-

tions were put together.

As an example N2a mode requires a ± 1.5 kHz frequency accuracy on the nodes. On the sensitivity vs. frequency offset graph this

number is translated to ± 3kHz as the receiver has no frequency error at all in the tests. This also practically means that in an applica-

tion that the same reference source (XO/TCXO) can be used in the Rx node as specified in the Tx node. In our example it means a ±

1500 [Hz] /169 [MHz] = ± 8.87 ppm reference source accuracy at either side of the link.

This logic is adhered throughout the document at the sensitivity vs. frequency offset graphs unless otherwise stated.

AN805: Si446x Wireless MBUS Receiver

Measurement Setup

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4. Wireless MBUS Measurement Results

4.1 S Mode

The following link parameters were used for the measurement:

• Center frequency: 868.3 MHz

• Chip rate: 32.768 kcps, 2 FSK modulation

• Frequency deviation: ±50 kHz

• Receiver filter BW: 264.5 kHz

• Packet Format: preamble (n = 15 or 279 – depending on the preamble length definition) x (01) + sync word “000111011010010110”

+ 20 byte payload + CRC

4.1.1 Receiver Sensitivity

Figure 4.1. S-Mode Receiver Sensitivity

Short preamble mode (S2, S1-M modes):

• 0% PER at strong RF i/p.

• The measured sensitivity for <1% PER is –105 dBm.

• The measured sensitivity for <20% PER is –106 dBm.

• The measured sensitivity for <80% PER is -108 dBm.

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Wireless MBUS Measurement Results

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4.1.2 Receiver Frequency Error Tolerance

Figure 4.2 S-Mode Receiver Frequency Error Tolerance on page 19 shows the frequency error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus frequency offset.

Figure 4.2. S-Mode Receiver Frequency Error Tolerance

The limits are placed at ± 85 ppm offset on the graph. Worst case transmitters (S1, S1m) will have a ± 60 ppm accuracy, worst case

receive modes (S2) will have a worst case ± 25 ppm accuracy. Therefore, the sum of the two numbers has been used to determine the

limits.

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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4.1.3 Receive Data Rate Error Tolerance

Figure 4.3 S-Mode Receiver Data Rate Error Tolerance on page 20 shows the data rate error tolerance capability of the receiver. The

plot shows the sensitivity of the receiver measured at 80% PER versus the percentage of data rate error.

Figure 4.3. S-Mode Receiver Data Rate Error Tolerance

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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4.1.4 Receiver Deviation Error Tolerance

Figure 4.4 S-Mode Receiver Deviation Error Tolerance on page 21 shows the deviation error tolerance capability of the receiver. The

plot shows the sensitivity of the receiver measured at 80% PER, versus the deviation error in kHz.

Figure 4.4. S-Mode Receiver Deviation Error Tolerance

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Wireless MBUS Measurement Results

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4.1.5 Receiver Blocking Performance

Figure 4.5 S-Mode Blocking on page 22 shows the selectivity/blocking performance of the receiver. The plot shows the receiver se-

lectivity with blockers on both the positive and negative frequency offsets with respect to the receiver. The selectivity was measured at

1% BER at various frequency offsets.

Figure 4.5. S-Mode Blocking

4.1.6 Conclusion

• Si446x has –108 dBm sensitivity in W-MBUS S mode. This is 8 dBm better than the W-MBUS S mode requirements.

• Si446x meets all the corners vs. frequency error, data rate error, and deviation error required by the W-MBUS standard.

• MBUS signal can be received with built-in Packet Handler in all the corner cases. This eliminates the need for any additional micro-

controller for data recovery. It also reduces the complexity of the packet handling code on the microcontroller.

• Si446x meets the ETSI Class2 blocking requirements.

• Si446x complies with the W-MBUS highest receiver performance class.

4.2 T Mode

Note: Only the “Meter to Other Device Modulation format results are presented in this section as the “Other Device to Meter” modula-

tion format is identical to mode S (Section 5.1)

The following link parameters were used for the measurement:

• Center frequency: 868.95 MHz

• Chip rate: 100 kcps, 2 FSK modulation

• Frequency deviation: ±50 kHz

• Receiver filter BW: 257 kHz

• Packet Format: preamble(n = 19) x (01) + sync word “0000111101” + 20 byte payload + CRC

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Wireless MBUS Measurement Results

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4.2.1 Receiver Sensitivity

Figure 4.6. T-Mode Receiver Sensitivity

• 0% PER at High RF i/p

• The measured sensitivity for <1% PER is –100 dBm

• The measured sensitivity for <20% PER is –102 dBm

• The measured sensitivity for <80% PER is –104.5 dBm

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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4.2.2 Receiver Frequency Error Tolerance

Figure 4.7 T-Mode Receiver Frequency Error Tolerance on page 24 and Figure 4.8 T-Mode Receiver Frequency Error Tolerance on

page 25 show the frequency error tolerance capability of the receiver. The figures show the sensitivity of the receiver measured at

80% PER versus frequency offset. Sensitivity vs. frequency offset curves are presented at various Tx signal DR values (nominal, mini-

mum, maximum) parameterized with various Tx signal deviation values (nominal, minimum, maximum).

Figure 4.7. T-Mode Receiver Frequency Error Tolerance

The limits are placed at ± 85 ppm offset on the graph. Worst case transmitters (T1) will have a ± 60 ppm accuracy; worst case receive

modes (T2) will have a worst case ± 25 ppm accuracy. Therefore, the sum of the two numbers has been used to determine the limits.

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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Figure 4.8. T-Mode Receiver Frequency Error Tolerance

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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4.2.3 Receiver Data Rate Error Tolerance

Figure 4.9 T-Mode Receiver Data Rate Error Tolerance on page 26 shows the data rate error tolerance capability of the receiver. The

plot shows the sensitivity of the receiver measured at 80% PER versus the data rate error in kHz.

Figure 4.9. T-Mode Receiver Data Rate Error Tolerance

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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4.2.4 Receiver Deviation Error Tolerance

Figure 4.10 T-Mode Receiver Deviation Error Tolerance on page 27 shows the deviation error tolerance capability of the receiver. The

plot shows the sensitivity of the receiver measured at 80% PER versus the deviation error in kHz.

Figure 4.10. T-Mode Receiver Deviation Error Tolerance

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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4.2.5 Receiver Blocking Performance

Figure 4.11 T-Mode Receiver Selectivities on page 28shows the selectivity/blocking performance of the receiver. The plots show re-

ceiver selectivity with blockers on both the positive and negative frequency offsets with respect to the receiver. The selectivity was

measured at 1% BER at various frequency offsets.

Figure 4.11. T-Mode Receiver Selectivities

4.2.6 Conclusion

• Si446x has –104.5 dBm sensitivity in W-MBUS T mode. This is 4.5 dBm better than the W-MBUS T mode requirements.

• Si446x meets all the corners (frequency error, data rate error, and deviation error) required by the W-MBUS standard.

• MBUS signal can be received with built-in Packet Handler in all the corner cases. This eliminates the need for any additional micro-

controller for data recovery. It also reduces the complexity of the packet handling code on the microcontroller.

• Si446x meets the ETSI Class2 blocking requirements.

• Si446x complies with the W-MBUS highest receiver performance class.

4.3 R2 Mode

The following link parameters were used for the measurement:

• Center frequency: 868.03 MHz

• Chip rate: 4.8 kcps, 2 FSK modulation

• Frequency deviation: ±6 kHz

• Receiver filter BW: 60 kHz

• Packet Format: preamble (n = 39) x (01) + sync word “000111011010010110” + 20 byte payload + CRC

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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4.3.1 Receiver Sensitivity

Figure 4.12. R-Mode Receiver Sensitivity

• 0% PER at strong RF i/p.

• The measured sensitivity for <1% PER is –113 dBm

• The measured sensitivity for <20% PER is –115 dBm

• The measured sensitivity for <80% PER is –117 dBm

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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4.3.2 Receiver Frequency Error Tolerance

Figure 4.13 R-Mode Receiver Frequency Error Tolerance on page 30 shows the frequency error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus frequency offset.

Figure 4.13. R-Mode Receiver Frequency Error Tolerance

Mode R2 is the only mode that is channelized and has a 60 kHz channel spacing specification. Now, let us have a look at a worst case

Tx scenario with the largest deviation and maximum frequency offset.

ModBW_max = 2 x deviation_max + DR = 2*7.2 kHz + 6 kbps = 19.4 kHz

single_sided_frequency_offset_max = 20 [ppm] * 868 [MHz] = 17.36 kHz

In such a worst case scenario the Tx signal can span between ± 27.06 kHz (with the ± worst case frequency offset) with regards to the

center frequency. That only leaves a "slack" of ± 2.94 kHz on the receiver to still comply with the 60 kHz channel spacing. This trans-

lates to a ± 3.4 ppm reference accuracy at the Rx side. With the current wording of the standard this is the only way to comply with the

60 kHz channel spacing specification.

The limit lines are set to ± 23.4 ppm (± 20 kHz).

AN805: Si446x Wireless MBUS Receiver

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4.3.3 Receiver Data Rate Error Tolerance

Figure 4.14 R-Mode Receiver Data Rate Error Tolerance on page 31 shows the data rate error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus the percentage of data rate error.

Figure 4.14. R-Mode Receiver Data Rate Error Tolerance

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4.3.4 Receiver Deviation Error Tolerance

Figure 4.15 R Mode Receiver Deviation Error Tolerance on page 32 shows the deviation error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus the deviation error in kHz.

Figure 4.15. R Mode Receiver Deviation Error Tolerance

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Wireless MBUS Measurement Results

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4.3.5 Receiver Blocking Performance

Figure 4.16 R2 Mode Receiver Selectivity on page 33 shows the selectivity/blocking performance of the receiver. The plot shows the

receiver selectivity with blockers on both the positive and negative frequency offsets with respect to the receiver. The selectivity was

measured at 1% BER at various frequency offsets.

Figure 4.16. R2 Mode Receiver Selectivity

4.3.6 Conclusion

• Si446x has –117 dBm sensitivity in W-MBUS R2 mode. This is 12 dBm better than the W-MBUS R2 mode requirements.

• Si446x meets all the corners vs. frequency error, data rate error, and deviation error required by the W-MBUS standard.

• MBUS signal can be received with built-in Packet Handler in all the corner cases. This eliminates the need for any additional micro-

controller for data recovery. It also reduces the complexity of the packet handling code on the microcontroller.

• Si446x meets the ETSI Class2 blocking requirements.

• Si446x complies with the W-MBUS highest receiver performance class.

AN805: Si446x Wireless MBUS Receiver

Wireless MBUS Measurement Results

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4.4 C Mode

The following link parameters were used for the measurement:

• Direction from meter:

• Center frequency: 868.95 MHz

• Chip rate: 100 kcps, 2 FSK modulation

• Frequency deviation: ±45 kHz

• Receiver filter BW: 214.04 kHz

• Packet Format: preamble (n = 16) x (01) + sync word “0101010000111101 0101010011001101” + 20 bytes payload + CRC

• Direction to meter:

• Center frequency: 869.525 MHz

• Chip rate: 50 kcps, 2 GFSK modulation

• Frequency deviation: ±25 kHz

• Receiver filter BW: 143.24 kHz

• Packet Format: preamble (n = 16) x (01) + sync word “0101010000111101 0101010011001101” + 20 byte payload + CRC

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4.4.1 Receiver Sensitivity

Figure 4.17. C-Mode Receiver Sensitivity

• Direction: Meter to other (C1, C2):

• 0% PER at strong RF i/p.

• The measured sensitivity for <1% PER is –104 dBm.

• The measured sensitivity for <20% PER is –106 dBm.

• The measured sensitivity for <80% PER is –109 dBm.

• Direction: Other to meter (C2):

• 0% PER at strong RF i/p.

• The measured sensitivity for <1% PER is –107 dBm.

• The measured sensitivity for <20% PER is –108 dBm.

• The measured sensitivity for <80% PER is –111 dBm.

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4.4.2 Receiver Frequency Error Tolerance

Figure 4.18 C Mode Receiver Frequency Error Tolerance from Meter / to Meter on page 36 shows the frequency error tolerance ca-

pability of the receiver. The plots show the sensitivity of the receiver measured at 80% PER versus frequency offset.

AN805: Si446x Wireless MBUS Receiver

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Figure 4.18. C Mode Receiver Frequency Error Tolerance from Meter / to Meter

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4.4.3 Receiver Data Rate Error Tolerance

Figure 4.19 C Mode Receiver Data Rate Error Tolerance on page 38 shows the data rate error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus the data rate error in ppm.

Figure 4.19. C Mode Receiver Data Rate Error Tolerance

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4.4.4 Receiver Deviation Error Tolerance

Figure 4.20 C Mode Receiver Deviation Error Tolerance (from Meter / to Meter) on page 39 shows the deviation error tolerance capa-

bility of the receiver. The plots show the sensitivity of the receiver measured at 80% PER versus the deviation error in kHz.

AN805: Si446x Wireless MBUS Receiver

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Figure 4.20. C Mode Receiver Deviation Error Tolerance (from Meter / to Meter)

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4.4.5 Receiver Blocking Performance

Figure 4.21 C Mode Receiver Selectivity on page 41 shows the selectivity/blocking performance of the receiver. The plots show the

receiver selectivity with blockers on both the positive and negative frequency offsets with respect to the receiver. The selectivity was

measured at 1% BER at various frequency offsets.

AN805: Si446x Wireless MBUS Receiver

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Figure 4.21. C Mode Receiver Selectivity

4.4.6 Conclusion

• Si446x has –109 dBm or –111 dBm sensitivity in W-MBUS C mode (depending on the direction). These are 8 dB and 11 dB better

than the W-MBUS C mode requirements.

• Si446x meets all the corners vs. frequency error, data rate error, and deviation error required by the W-MBUS standard.

• MBUS signal can be received with built-in Packet Handler in all the corner cases. This eliminates the need for any additional micro-

controller for data recovery. It also reduces the complexity of the packet handling code on the microcontroller.

• Si446x meets the ETSI Class2 blocking requirements.

• Si446x complies with the W-MBUS highest receiver performance class.

4.5 N(1,2)a/b/e/f Mode

The following link parameters were used for the measurement:

• Center frequency: 169.40625 MHz

• Chip rate: 4.8 kbps, 2 GFSK modulation

• Frequency deviation: ±2.4 kHz

• Receiver filter BW: 10.33 kHz

• Packet Format: preamble(n = 8) x (01) + sync word “11110110 10001101” + 20 bytes payload + CRC

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4.5.1 Receiver Sensitivity

Figure 4.22. N(1,2)a/b/e/f Mode Receiver Sensitivity

• <1% PER at High RF i/p.

• The measured sensitivity for <1% PER is –117 dBm.

• The measured sensitivity for <20% PER is –118 dBm.

• The measured sensitivity for <80% PER is –120.5 dBm.

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4.5.2 Receiver Frequency Error Tolerance

Figure 4.23 N(1,2)a/b/e/f Mode Receiver Frequency Error Tolerance on page 44 shows the frequency error tolerance capability of the

receiver. The plot shows the sensitivity of the receiver measured at 80% PER versus frequency offset.

Figure 4.23. N(1,2)a/b/e/f Mode Receiver Frequency Error Tolerance

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4.5.3 Receiver Data Rate Error Tolerance

Figure 4.24 N(1,2)a/b/e/f Mode Receiver Data Rate Error Tolerance on page 45 shows the data rate error tolerance capability of the

receiver. The plot shows the sensitivity of the receiver measured at 80% PER versus percentage of data rate error.

Figure 4.24. N(1,2)a/b/e/f Mode Receiver Data Rate Error Tolerance

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4.5.4 Receiver Deviation Error Tolerance

Figure 4.25 N(1,2)a/b/e/f Mode Receiver Deviation Error Tolerance on page 46 shows the deviation error tolerance capability of the

receiver. The plot shows the sensitivity of the receiver measured at 80% PER versus the deviation error in kHz.

Figure 4.25. N(1,2)a/b/e/f Mode Receiver Deviation Error Tolerance

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4.5.5 Receiver Blocking Performance

Figure 4.26 N(1,2)a/b Mode Receiver Selectivity on page 47 shows the selectivity/blocking performance of the receiver. The plot

shows the receiver selectivity with blockers on both the positive and negative frequency offsets with respect to the receiver. The selec-

tivity was measured at 1% BER at various frequency offsets.

Figure 4.26. N(1,2)a/b Mode Receiver Selectivity

4.5.6 Conclusion

• Si446x has –120.5 dBm sensitivity in W-MBUS N(1,2)a/b/e/f mode. This is 8.5 dB better than the W-MBUS N(1,2)a/b/e/f mode re-

quirements.

• Si446x meets all the corners vs. frequency error, data rate error, and deviation error required by the W-MBUS N(1,2)a/b/e/f stand-

ard.

• MBUS signal can be received with built-in Packet Handler in all the corner cases. This eliminates the need for any additional micro-

controller for data recovery. It also reduces the complexity of the packet handling code on the microcontroller.

• Si446x meets the ETSI Class2 blocking requirements.

• Si446x complies with the W-MBUS highest receiver performance class.

4.6 N(1,2)c/d Mode

The following link parameters were used for the measurement:

• Center frequency: 169.43125 MHz

• Chip rate: 2.4 kbps, 2 GFSK modulation

• Frequency deviation: ±2.4 kHz

• Receiver Filter BW: 11.58 kHz

• Packet Format: preamble (n = 8) x (01) + sync word “11110110 10001101” + 20 bytes payload + CRC

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4.6.1 Receiver Sensitivity

Figure 4.27. Nc/d Mode Receiver Sensitivity

• <1% PER at High RF i/p.

• The measured sensitivity for <1% PER is –116 dBm.

• The measured sensitivity for <20% PER is –118 dBm.

• The measured sensitivity for <80% PER is –120.5 dBm.

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4.6.2 Receiver Frequency Error Tolerance

Figure 4.28 Nc/d Mode Receiver Frequency Error Tolerance on page 49 shows the frequency error tolerance capability of the receiv-

er. The plot shows the sensitivity of the receiver measured at 80% PER versus frequency offset.

Figure 4.28. Nc/d Mode Receiver Frequency Error Tolerance

The limits are placed at ± 21 ppm offset on the graph.Worst case transmitters will have a ±11.5 ppm accuracy. In such a narrowband

worst case receive modes can have a worst case ±9.5 ppm accuracy. Therefore, the sum of the two numbers has been used to deter-

mine the limits.

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4.6.3 Receiver Data Rate Error Tolerance

Figure 4.29 Nc/d Mode Receiver Data Rate Error Tolerance on page 50 shows the data rate error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus the percentage of data rate error.

Figure 4.29. Nc/d Mode Receiver Data Rate Error Tolerance

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4.6.4 Receiver Deviation Error Tolerance

Figure 4.30 Nc/d Mode Receiver Deviation Error Tolerance on page 51 shows the deviation error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus the deviation error in Hz.

Figure 4.30. Nc/d Mode Receiver Deviation Error Tolerance

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4.6.5 Receiver Blocking Performance

Figure 4.31 Nc/d Mode Receiver Selectivity on page 52 shows the selectivity/blocking performance of the receiver. The plot shows

the receiver selectivity with blockers on both the positive and negative frequency offsets with respect to the receiver. The selectivity was

measured at 1% BER at various frequency offsets.

Figure 4.31. Nc/d Mode Receiver Selectivity

4.6.6 Conclusion

• Si446x has –120.5 dBm sensitivity in W-MBUS Nc/d modes, which is 5.5 dB better than the W-MBUS Nc/d mode requirements.

• Si446x meets all the corners vs. frequency error, data rate error, and deviation error required by the W-MBUS standard.

• MBUS signal can be received with built-in Packet Handler in all the corner cases. This eliminates the need for any additional micro-

controller for data recovery. It also reduces the complexity of the packet handling code on the microcontroller.

• Si446x meets the ETSI Class2 blocking requirements.

• Si446x complies with the W-MBUS highest receiver performance class.

4.7 N2g Mode

The following link parameters were used for the measurement:

• Center frequency: 169.4375 MHz

• Chip rate: 9.6 kcps, 4 GFSK modulation

• Frequency deviation: ± 2.4 kHz

• Receiver filter BW: 26 kHz

• Packet Format: preamble (n=8) x (AD) + sync word “DDDDADDA DAAADDAD” + 20 bytes payload + CRC

Data transmitted using 4GFSK modulation shall be NRZ encoded, with the lowest frequency corresponding to binary “01” (symbol A),

the second frequency corresponding to binary “00” (B), the third frequency corresponding to binary “10” (C) and the highest frequency

corresponding to binary “11” (D).

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4.7.1 Receiver Sensitivity

Figure 4.32. N2g Mode Receiver Sensitivity

• The measured sensitivity for <1% PER is –108 dBm.

• The measured sensitivity for <20% PER is –110 dBm.

• The measured sensitivity for <80% PER is –113 dBm

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4.7.2 Receiver Frequency Error Tolerance

Figure 4.33 N2g Mode Receiver Frequency Error Tolerance on page 54 shows the frequency error tolerance capability of the receiv-

er. The plot shows the sensitivity of the receiver measured at 80% PER versus frequency offset.

Figure 4.33. N2g Mode Receiver Frequency Error Tolerance

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4.7.3 Receiver Deviation Error Tolerance

Figure 4.34 N2g Mode Receiver Deviation Error Tolerance on page 55 shows the deviation error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus the deviation error in Hz.

Figure 4.34. N2g Mode Receiver Deviation Error Tolerance

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4.7.4 Receiver Blocking Performance

Figure 4.35 N2g Mode Receiver Selectivity on page 56 shows the selectivity/blocking performance of the receiver. The plot shows the

receiver selectivity with blockers on both the positive and negative frequency offsets with respect to the receiver. The selectivity was

measured at 1% BER at various frequency offsets.

Figure 4.35. N2g Mode Receiver Selectivity

4.7.5 Conclusion

• Si446x has –113 dBm sensitivity in W-MBUS N2g modes, which is 9 dB better than the W-MBUS N2g mode requirements.

• Si446x meets all the corners vs. frequency error, data rate error, and deviation error required by the WMBUS standard.

• MBUS signal can be received with built-in Packet Handler in all the corner cases. This eliminates the need for any additional micro-

controller for data recovery. It also reduces the complexity of the packet handling code on the microcontroller.

• Si446x meets the ETSI Class2 blocking requirements.

• Si446x complies with the W-MBUS highest receiver performance class.

4.8 F Mode

The following link parameters were used for the measurement:

• Center frequency: 433.82 MHz

• Chip rate: 2.4 kcps, 2 FSK modulation

• Frequency deviation: ±5.5 kHz

• Receiver Filter BW: 46.3 kHz

• Packet Format: preamble (n = 39) x (01) + sync word “000111010110100101” + 20 bytes payload + CRC

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4.8.1 Receiver Sensitivity

Figure 4.36. F Mode Receiver Sensitivity

• 0% PER at High RF i/p with 32 bit preamble

• The measured sensitivity for <1% PER is –114 dBm.

• The measured sensitivity for <20% PER is –117 dBm.

• The measured sensitivity for <80% PER is –118.5 dBm.

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4.8.2 Receiver Frequency Error Tolerance

Figure 4.37 F Mode Receiver Frequency Error Tolerance on page 58 shows the frequency error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus frequency offset.

Figure 4.37. F Mode Receiver Frequency Error Tolerance

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4.8.3 Receiver Data Rate Error Tolerance

Figure 4.38 F Mode Receiver Data Rate Error Tolerance on page 59 shows the data rate error tolerance capability of the receiver.

The plot shows the sensitivity of the receiver measured at 80% PER versus the data rate error in ppm.

Figure 4.38. F Mode Receiver Data Rate Error Tolerance

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4.8.4 Receiver Deviation Error Tolerance

Figure 4.39 F Mode Receiver Deviation Error Tolerance on page 60 shows the deviation error tolerance capability of the receiver. The

plot shows the sensitivity of the receiver measured at 80% PER versus the deviation error in kHz.

Figure 4.39. F Mode Receiver Deviation Error Tolerance

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4.8.5 Receiver Blocking Performance

Figure 4.40 F Mode Receiver Selectivity on page 61 shows the selectivity/blocking performance of the receiver. The plot shows the

receiver selectivity with blockers on both the positive and negative frequency offsets with respect to the receiver. The selectivity was

measured at 1% BER at various frequency offsets.

Figure 4.40. F Mode Receiver Selectivity

4.8.6 Conclusion

• Si446x has –118.5 dBm sensitivity in W-MBUS F mode. This is 2.5 dB better than the W-MBUS F mode requirements.

• Si446x meets all the corners vs. frequency error, data rate error, and deviation error required by the W-MBUS standard.

• MBUS signal can be received with built-in Packet Handler in all the corner cases. This eliminates the need for any additional micro-

controller for data recovery. It also reduces the complexity of the packet handling code on the microcontroller.

• Si446x meets the ETSI Class2 blocking requirements.

• Si446x complies with the W-MBUS highest receiver performance class. Complies with the W-MBUS highest receiver performance

class.

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5. Document Change List

5.1 Revision 0.1 to Revision 0.2

• Add clarification regarding the HW platform and tools for configuring the radio.

5.2 Revision 0.2 to Revision 0.3

• All the data was updated for Rev C based on the EN13757-4-2013 w-MBUS standard.

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