Upload
socaciu-viorica
View
49
Download
6
Tags:
Embed Size (px)
Citation preview
www.knx.org
KNX RF – Then, Now, Future
Inn Style – Maarssen – 8 maart 2012
Joost Demarest – System and Admin Director
KNX Association Diegem/Brussels Belgium
KNX Radio Frequency
Mr. Joost Demarest
Page No. 2
March 12 KNX: The worldwide STANDARD for Home & Building Control
Contents
1. Original system requirements for KNX RF
2. Relevant standards
3. KNX RF Physical Layer
4. KNX RF telegram structure
5. KNX RF retransmitter functionality
6. KNX (RF) Easy Mode
7. KNX Bibat procedure
8. Recent KNX RF extensions
9. Future of KNX RF
KNX Radio Frequency
Mr. Joost Demarest
Page No. 3
March 12 KNX: The worldwide STANDARD for Home & Building Control
Original system requirements for KNX RF
retrofit market mainly
home & residential market
Decentralised (no master) but
centralised functions possible
usable as stand alone solution and together with other KNX media
(media couplers)
Implementation on off-the-shelf components, small footprint
Re-transmitter use only for bigger installations
Bi- and unidirectional implementations possible
Low power consumption
for all application domains of home automation
lighting, shutters & blinds, security, HVAC, ..
KNX RF metering protocol as subsystem to KNX RF
Non-PC based programming (« Easy installation »), future tool
support
KNX Radio Frequency
Mr. Joost Demarest
Page No. 4
March 12 KNX: The worldwide STANDARD for Home & Building Control
Layers 3-7 = EN 50090-series
Layers 1-2, approved by CLC/TC 205 as EN 50090-5-3
common solution with/according to CEN/TC 294
EN 13757-3/-4 (Metering!)
RF according to CEPT/ERC 70-03 (868 MHz - Band)
Data Link Layer according to IEC 870-5-2 (FT3 - Protocol)
Relevant Standards
KNX Radio Frequency
Mr. Joost Demarest
Page No. 5
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX RF Physical Layer (1) acc. to CEPT/ERC 70-03
PO
WE
R [
ER
P ]
868.0 868.6 870 [MHz]
FREQUENCY
Application: SRD SRD MAC, SRD SRD
Alarms Alarms Alarms
Duty Cycle: < 1% < 1% < 0.1 % <0.1% t.b.d. <10 % < 10% 100%
[mW]
500
25
10
5
25 mW
10mW
25 mW
5 mW
10mW
25 mW
600 kHz 500 kHz 300 kHz 100 250 kHz
500mW
25 mW
100kHz
KNX Radio Frequency
Mr. Joost Demarest
Page No. 6
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX RF Physical Layer (2)
Characteristic Value Remark
Frequency band 868 .... 868.6 MHZ 1% duty cycle
Center frequency fc = 868.300 MHz
Frequency tolerance +/-35 ppm +/-30.4 kHz
Modulation FSK
FSK deviation fDEV = ± 40 kHz to ± 80 kHz typically 50kHz
Rx Bandwidth 300 kHz
Rx sensitivity typical -95 dBm (BER 10-4) -80 dBm minimum
Tx minimum ERP 0 dBm
Bit coding Manchester
bit "0" is coded as fHI to
fLO transition, chip
sequence "10" bit "1" is
coded as fLO to fHI
transition, chip sequence
"01”
Bitrate 16.384 kBit/sec
Chiprate (transmit) 32.768 kChips/secenables usage of clock
crystal
Jitter per transition Tx +- 5 µsec
Blocking performance Class 2 EN 300 220 1, 9.3.3 for
class 2 receivers
Chip rate tolerance Tx +/- 1.5%
Chip rate tolerance Rx +/- 2%
KNX Radio Frequency
Mr. Joost Demarest
Page No. 7
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX RF Physical Layer (3)
Characteristic Value Remark
Duty cycle 1 %
Preamble 30 Chips
Manchester violation chip sequence "000111"necessary for capture
effectSync word chip seq "011010010110"
Postamble 2 to 8 chips
Hamming distance 6
Protection CRC 16 bit
Data link layer IEC 870-5-1/2 FT3
Typical air time per frame ~16ms typical 4 byte datapoint
Retransmitters up to 3 cascading possible
KNX Radio Frequency
Mr. Joost Demarest
Page No. 8
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX RF general frame structure
Preamble max. 15 x 01 chip preamble for synchronisation
Manch. Violation
Sync Word
Block 1 10 bytes fixed length, more info on next slide
CRC 2 bytes CRC after each data block
Further blocks 16 bytes details of block 2 on next slides
Last block 1 to 16 bytes
Postamble 2 to 8 chips provides defined end of frame
Block 1 CRC Preamble Block 2 Postamble CRC CRC ...
IEC870-5-2 (FT3)
KNX Radio Frequency
Mr. Joost Demarest
Page No. 9
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX RF Block 1
Length 1 byte total number of user bytes counting
from C-field
C-field 1 byte fixed to value 44h
Esc 1 byte escape code to separate KNX from
metering (fixed to value FFh)
Ctrl 1 byte uni or bidirectional sender
signal strength
battery state
SN 6 bytes Serial number/domain address of
sender
C-field ESC Length Ctrl SN
KNX Radio Frequency
Mr. Joost Demarest
Page No. 10
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX RF Block 2
Ctrl 1 byte standard or extended?
Standard frame variable difference with frame on other
media lies in
- LFN: duplication avoidance
- Domain address bit: indicates
significance of SN field in Block 1
Data variable actual payload, remaining in next
block
Standard frame Data Ctrl
KNX Radio Frequency
Mr. Joost Demarest
Page No. 11
March 12 KNX: The worldwide STANDARD for Home & Building Control
Re-transmitter Technology
RT
T = Transmitter
= Receiver
= Retransmitter
R
M-1-2(LFN)
M-1(LFN)
M(LFN)
T
RT1
RT2
RM-1(LFN)
M(LFN)
M-2(LFN)
up to 3 Retransmitters are supported
No need for meshed networking
Link Layer Frame Number (LFN) + history list
solution to multipath communication
and avoiding message duplication:
routing counter
Limitation of number of retransmissions
short interframe time + random delay: 0...10 ms
avoiding collisions of retransmitted messages
Dedicated retransmitters avoid complexity and overhead in
normal end devices!
KNX Radio Frequency
Mr. Joost Demarest
Page No. 12
March 12 KNX: The worldwide STANDARD for Home & Building Control
Concept of KNX Easy Installation
Device Functionality is made known to the partner device or configurator
via “E-Mode channels”
Instead of via ETS product database entries
Functionality of product is already contained in E-Mode device –
S-Mode device is in theory “empty”
E-Mode channels are a collection of data points and parameters
Each Group Object has one or more different connection codes, depending
on its functionality (e.g. switch, time, temperature, …)
During configuration, group objects with the same
connection code can be linked.
Push button: same approach but partner device decides
whether linking is possible
Easy installations are limited to one single line
KNX Radio Frequency
Mr. Joost Demarest
Page No. 13
March 12 KNX: The worldwide STANDARD for Home & Building Control
Example Easy channel Heating actuator
KNX Radio Frequency
Mr. Joost Demarest
Page No. 14
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX Easy Controller Mode
One single, central controller takes over role of ETS
Procedure
Assignment of unique individual address to each found E-Mode device
Read out of the E-Mode channels and parameters
Show capabilities of devices on controller’s display
Installer indicates which channels shall be linked
Controller decides on group addresses and parameters and
downloads the devices
I only have Channel
CH_motion_detector_basic here
Group
Addresses
Associations
Parameters
Group
Addresses
Associations
Parameters
According the links requested by the user, this is
your address table, association table and
parameters block:
Channel
CH_LIGHT_ACTUATOR_COMPLEX
selected here
According the links requested by the user, this is
your address table, association table and
parameters block:
KNX Radio Frequency
Mr. Joost Demarest
Page No. 15
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX Push button Mode
No central intelligence
Procedure
Each device searches for itself a free Individual Address
Installers first selects actuator channel (e.g. by pressing a button)
Installer then selects sensor channel
Devices negotiate whether or not a link can be established
Linking must always be done two by two
I am 05FFh,
0100017A34AAh
I am 05FFh,
0908013FA14Dhh
Enter_Config_Mode
Start_Link
I am CH_light-actuator-complex
COOL.
I am ch_motion_detector_BASIC
I have an input
CC_TIMED_STARTSTOP
GrEAT! MY output cc_TIMED_STARTSTOP
HAS Group address 8300h. USE that!
KNX Radio Frequency
Mr. Joost Demarest
Page No. 16
March 12 KNX: The worldwide STANDARD for Home & Building Control
Extended group address table because of
Unidirectional devices
T = Transmitter
= Receiver
T
R
Sensor 1 Device SN°
SN°=1
R T
Actuator
Device SN°
SN°=3
Partner SN°
SN°=1 GA=1
T
Sensor 2 Device SN°
SN°=2 GA=1 = Channel
SN°=2
Partner GA
GA°=1
GA°=1
Undirectional senders use fixed and unchangeable Group addresses
Partner device (actuator) has to have extended group address table –
combination with serial number of sensor device makes group address
unique
Big drawback: if sensor needs to be replaced also reprogramming
actuator!
KNX Radio Frequency
Mr. Joost Demarest
Page No. 17
March 12 KNX: The worldwide STANDARD for Home & Building Control
RF extension for bidirectional battery powered
devices (BiBat)
Bidirectional battery-driven RF devices can’t be in receive-mode all
the time because of battery-lifetime
The BiBat extension reduces the active receive windows
of battery operated receivers to a minimum by means of a time slot
procedure
Application:
- heating actuators for radiators
- bidirectional room units
- fire/smoke sensors remote controls with
feedback
Typical battery life times 1-3 years
KNX Radio Frequency
Mr. Joost Demarest
Page No. 18
March 12 KNX: The worldwide STANDARD for Home & Building Control
Recent extensions KNX RF
RF « ready »
Single RF channel version – upgrade of version 1 of KNX RF
RF « multi »
3 fast RF channels and 2 slow RF channels
Bibat
single RF channel version, unchanged compared to version 1 of
HBES RF
Bibat 2
2 RF channels
KNX Radio Frequency
Mr. Joost Demarest
Page No. 19
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX RF Ready
Single channel, evolution with 4.8ms preamble for Tx
Rx change to ignore some bits in CTRL field
The rest of the stack remains the same
Only a software upgrade of existing products
All new developments shall be RF ready
500mW
868MHz 868.3 868.6 868.9 869.2 869.4 869.7 870MHz
Bibat
KNX RF ready
Duty Cycle 1%
25mW
KNX Radio Frequency
Mr. Joost Demarest
Page No. 20
March 12 KNX: The worldwide STANDARD for Home & Building Control
KNX RF multi
3 RF fast channels for low latency devices
2 RF slow channels for battery powered devices
F3 optional
25mW in F3 is now allowed by regulation
Energy savings Allow very low power consumption for receivers
KNX Radio Frequency
Mr. Joost Demarest
Page No. 22
March 12 KNX: The worldwide STANDARD for Home & Building Control
Compatibility scheme
Existing Add
KNX RF « ready »
products
Tx Ok
Rx Ok
Single channel
Tx Ok
Rx Ok
Tx Ok Rx Ok
Multi channel
Add
KNX RF « multi »
products
Downgrade via
manuf specific
action
KNX RF « ready »
products
Add
KNX RF « multi »
products
Add
KNX RF « multi »
products
Existing
KNX Radio Frequency
Mr. Joost Demarest
Page No. 23
March 12 KNX: The worldwide STANDARD for Home & Building Control
Future of KNX RF (1)
KNX is No. 1 system for home and building control
Especially for the professional market with complex installations
Only system with several supported media
Only system with scalable configuration modes
Usable in different application domains
Supported by many manufacturers
Accepted by many installers
Current Radio Frequency situation
Radio Frequency is a high volume and fast growing business
Many manufacturers however develop and market proprietary
solutions
Many manufacturers wish to change to an open standard
There is no clear number one RF standard, many “standards”
still result in products with proprietary communication
KNX Radio Frequency
Mr. Joost Demarest
Page No. 24
March 12 KNX: The worldwide STANDARD for Home & Building Control
Future of KNX RF (2)
Current KNX RF situation
Insufficient number of involved manufacturers
Insufficient number of available devices
Specification of Encryption and Authentication still work in progress
Use of different configuration modes leads to impossibility to link products of different
manufacturers
No direct tool support - support of current KNX RF solution would lead to difference in look
and feel of ETS for RF
Coupling to TP via manufacturer media coupler specific solutions and ETS plug ins
Not usable for complex installations
What is needed ?
Streamline addressing scheme between TP/PL and RF
If accessed by ETS, devices shall allow the use of a domain address common to the
installation instead of individual serial number
Possibility to develop much simpler media couplers between TP and RF
Finalize the KNX Security concept for encryption and authentication
Support RF in ETS and add RF to KNX Basic course training
www.knx.org
Thank you for your attention!
For more information
Joost Demarest – KNX Association cvba
Tel: +32 2 775 86 44
E-Mail: [email protected]
Web: www.knx.org