ISO compliant RTLS based on Chirp Spread Spectrum

Transcription

1 Wireless Congress 2008, Munich Systems & Applications ISO compliant TLS based on Chirp Spread Spectrum Albrecht ommel System Architect

2 Agenda The ISO/IEC Standard The ISO/IEC Air Interface Example Systems based on Status ISO/IEC Standardization Process Other LTS Standards Forecast on future Developments and Opportunities Nanotron Technologies GmbH 2

3 ISO/IEC JTC1 SC31 Landscape ISO (Internat. Org. for Standardization) IEC (Internat. Electronical Commission) TC1 Screws TC4 Bearings Steel, Petrol, Food, SC17 (Personal ID) JTC1 Joint Technical Committee 1 (IT) SC31 Automatic Identification And Data Capturing SC37 (Biometrics) National Bodies (ANSI, DIN, JISC,...) WG1 Carrier WG2 Structure WG3 Conform. WG4 FID WG5 TLS WG6 MIIM ISO/IEC Nanotron Technologies GmbH 3

4 ISO/IEC Standard Parts defines components of TLS systems Application Programming Interface (API) : 2.4 GHz Air Interface : 433 MHz proposal (withdrawn) : GLS GeoLocatingSystem via Satellite (withdrawn) : 2.4 GHz Personal Area Network (PAN) Air Interface UWB (t.b.d.) Nanotron Technologies GmbH 4

5 ISO/IEC System Infrastructure (Vendor Specific) T TLS Server API TLS Application AI T AI eader defines API and Air Interface Tag (up to x 1000 s) Infrastructure is Vendor Specific (wired / wireless) Air Interface ( , ,...) Nanotron Technologies GmbH 5

6 ISO/IEC API and Air IF Query Struct Blinkesponse Air Interface eader Infrastructure TLS Server OpenSession() Struct Sessionesponse QuerySession() Struct Blinkesponse TLS Application CloseSession() Vendor Specific ISO/IEC API Application Specific Nanotron Technologies GmbH 6

7 Air Interface T Air Interface TLS Server Nanotron Technologies GmbH 7

8 Physical Layer Modulation 2-ary orthogonal CSS (mandatory) - 80/22 MHz Bandwidth, Center Frequency MHz 1 F Channel - 22 MHz Bandwidth, Center Frequency MHz, 14 F Channels 8- or 64-ary orthogonal DQPSK-CSS (optional) - 22 MHz Bandwidth: Center Frequency , 14 Channels Data ates 1 Mbit/s, 250 kbit/s Nanotron Technologies GmbH 8

9 Physical Layer 2-ary Orthogonal CSS Modulation Chirp BW 80 (22) MHz Bit ate = Symbol ate - 1E6 bit/s kbit/s Simple Coding - 0 = Downchirp - 1 = Upchirp Nanotron Technologies GmbH 9

10 Physical Layer 2-ary Orthogonal CSS eceiver Up-Chirp and Down-Chirp are orthogonal and easy to separate Correlator Up 1 1 O 1 O Up Up Down Up Down Down eference Chirp anging and Localization: Simple and precise TOA (Time of Arrival) evaluation Nanotron Technologies GmbH 10

11 Physical Layer 2-ary Orthogonal CSS PHY Packet Format PHY Header & MAC Frame Preamble (30 alternating bits) Start of Frame Delimiter (64 bits) Nanotron Technologies GmbH 11

12 Physical Layer 2-ary Orthogonal CSS PHY Packet Format Scrambler Polynomial g(d) = D7 + D4 + D0, EXOed with bit stream eference Modulator Diagram Nanotron Technologies GmbH 12

13 Physical Layer DQPSK-CSS Modulation Differential Quadrature Phase Shift Keying Band plan corresponds with b DQPSK-CSS approved in IEEE a Chirp BW 22 MHz, 14 F Channels Sub-Chirp Freq. Offsets +/ MHz 4 different Sub-Chirp Sequences: I, II, III, and IV (up to 4 x 14 channels) Provides sub-chirp sequence division AND frequency division Bit ate - 1E6 bit/s (3/4 symbol mapping) kbit/s (6/32 symbol mapping) Symbol ate symbols/s Nanotron Technologies GmbH 13

14 Physical Layer DQPSK-CSS Sub-Chirps and Time Gaps Pairs of Time Gaps defined Time Gaps applied alternately between subsequent chirp symbols Provides sharper orthogonality between chirp symbols Nanotron Technologies GmbH 14

15 Physical Layer DQPSK-CSS eference Modulator Nanotron Technologies GmbH 15

16 Physical Layer DQPSK-CSS Symbol Mapping Data to 8-ary Bi-orthogonal Code Word Mapping (r=3/4) 3-bit data symbol b 0-2 is mapped to 4-chip bi-orthogonal code word c 0-3 Data to 64-ary Bi-orthogonal Code Word Mapping (r=6/32) For 250 kbit/s data rate, 6-bit data symbols are mapped to 32-chip bi-orthogonal code words Nanotron Technologies GmbH 16

17 Physical Layer DQPSK-CSS Preamble and SFD Preamble SFD Nanotron Technologies GmbH 17

18 MAC Layer MAC Frame Types Nanotron Technologies GmbH 18

19 MAC Layer MAC Frame Formats ACK Data Broadcast equest to Send Clear to Send Nanotron Technologies GmbH 19

20 MAC Layer 2-Way Handshake SIFS (Short Inter Frame Space) = 8 µs T_round, T_reply measured for anging Nanotron Technologies GmbH 20

21 MAC Layer 3-Way Handshake 3-Way handshake initiates a equest-to-send and waits for Clear-to-Send prior to data transmission Used to overcome hidden-node problem: used for virtual carrier sensing (see later) T_round, T_reply measured for anging Nanotron Technologies GmbH 21

22 MAC Layer Media Access Methods ALOHA Immediate Access w/o listening for any activity CSMA/CA Enery detect Average power sensing during CIFS period Physical carrier sense Sense for CIFS duration on medium Virtual carrier sense Evaluating Type and Length fields of incoming traffic For all 3 Methods above: Backoff when media is busy Nanotron Technologies GmbH 22

23 Tag Application Layer Tag Application Packet Types Four Types of Tag Application Packets Command Packets Used by infrastructure to transmit instructions to tags eport Packets Used by tags to transmit information to the infrastructure anging Packets Used for anging Blink Packets Broadcast packets transmitted by tags, e.g. for TLS via TDOA Nanotron Technologies GmbH 23

24 Tag Application Layer Tag Application States 5 different Tag Application States Infrastructure can instruct the TAG application to go to desired states or to go through sequences of states Nanotron Technologies GmbH 24

25 Example System 5 T Sleep State T 1 Default State (Broadcasting) T Blink State 4 Tag enters equipped area Server Locating Application 3 T Tag moves into another area Default State (Broadcasting) 2 T anging State Infrastructure instructs Tag to enter anging State Server anging Application Nanotron Technologies GmbH 25

26 Standardization Status of CD ballot Feb. 04, 2009 Ballots Final CD eview Oct. 19, 2008 CD Ballot esolution Mar. 04, 2009 NP WD CD FCD FDIS IS S0 Preliminary Stage S1 S2 S3 S4 Proposal Stage March 2007 Preparatory Stage Committee Stage Approval Stage S5 Publication Stage Nanotron Technologies GmbH 26

27 Standardization Other TLS Standards ISO/IEC (API, common for all Air Interfaces) Stage 5 (IS) since Feb ISO/IEC Stage 5 (IS) since Dec BPSK DSSS (Direct Sequence Spread Spectrum) Modulation - Center freq. 2441,75 MHz, BW 60 MHz - Data rate: ~60 kbit/s - Packet length bits 2-Tone OOK/FSK Modulation - Center Freq. 2441,75 MHz, BW 60 MHz - Data rate ~20 kbit/s - Packet length bits Short Distance Magnetic Link (115 MHz, 127 MHz) - Data rate 2,048 kbit/s Nanotron Technologies GmbH 27

28 Forecast, future Developments ISO/IEC (UWB) t.b.d. ISO/IEC Improvement of anging/localization Accuracy Improvement of Power Efficiency Development of Application Software for Emerging Markets & Applications Nanotron Technologies GmbH 28

29 For more information.. Please check Proceeding Papers Thank You! Contact: ainer Hach ( Editor) Albrecht ommel Nanotron Technologies GmbH Alt-Moabit Berlin Tel.: +49 (0) Nanotron Technologies GmbH 29