Project: IEEE P Working Group for Wireless Personal Area Networks N

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1 Project: IEEE P Working Group for Wireless Personal Area Networks N (WPANs( WPANs) Title: [Samsung Electronics (SAIT) CFP Presentation] Date Submitted: [January, 2005] Source: [(1) Chia-Chin Chong, Su Khiong Yong, Young-Hwan Kim, Jae-Hyon Kim, Seong-Soo Lee (2) A. S. Dmitriev, A. I. Panas, S. O. Starkov, Yu. V. Andreyev, E. V. Efremova, L. V. Kuzmin (3) Haksun Kim, Jaesang Cha] Company: [(1) Samsung Electronics Co., Ltd. (Samsung Advanced Institute of Technology (SAIT)) (2) Institute of Radio Engineering and Electronics (IRE) (3) Samsung Electro-Mechanics Co., Ltd.] Address: [(1) RF Technology Group, Comm. & Networking Lab., P. O. Box 111, Suwon , Korea. (2) Russian Academy of Sciences, 11 Mokhovaya Street, Moscow , Russia Federation. (3) 314, Maetan-3Dong, Youngtong-Gu, Suwon, Gyeonggi-Do, Korea ] Voice: [ ], FAX: [ ], [chiachin.chong@samsung.com] Re: [Response to IEEE a Call for Proposals (04/380r2)] Abstract: [Proposal for the IEEE a PHY standard based on the UWB direct chaotic communications technology.] Purpose: [Proposal for the IEEE a PHY standard.] Notice: This document has been prepared to assist the IEEE P It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P Slide 1

2 Samsung Electronics (SAIT) CFP Presentation for IEEE a Alternative PHY UWB Direct Chaotic Communication System Presented by: Chia-Chin Chong Samsung Advanced Institute of Technology (SAIT), Korea Slide 2

3 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 3

4 Characteristics of Chaotic Signal (1) Simple circuits Chaotic signal can be generated directly into the desired microwave band by a chaotic generator Low cost implementation The simple circuit leads to low cost product Multipath resistance Wideband signal is very immune against multipath fading Good spectral properties Non-periodic with a flat (or tailored) spectrum Flexibility Chaotic radio pulse with different time duration can have the same bandwidth Slide 4

5 Characteristics of Chaotic Signal (2) Amplitude PSD, db Time, ns Frequency, GHz Slide 5

6 Characteristics of Chaotic Signal (3) t T S(f) f f t 3T Slide 6

7 Direct Chaotic Communication (DCC) Chaotic source generates oscillations directly in a specified microwave band. Information component is put into the chaotic carrier using a stream chaotic radio pulses. Information is retrieved from the chaotic radio pulses without intermediate heterodyning. Most simple non-coherent receiver is used. Slide 7

8 Direct Chaotic Signal Generation Direct Chaos Generator Chaotic Radio Pulse Time Signal Binary Information Slide 8 Frequency Spectrum

9 Chaotic Generator Model Oscillator circuit Experiment device Slide 9

10 Mathematical Model System of 1 st and 2 nd order differential equations with 4.5 degrees of freedom x 2 x 3 x 4 x System Equations Tx x1 mf( x5) + α + α + α x 2 3 x x = + α x ω + ω + ω + ω x x x x = ω = α = α x = α x 1 2 x x 3 4 Runge-Kutta Method y(1) = (m*fx5 - X1)/T; y(2) = W1*W1*(X1- X3); y(3) = X2 - A1*X3; y(4) = A2*y3-W2*W2*X5; y(5) = X4 - A2*X5; y(6) = A3*y(5)-W3*W3*X7; y(7) = X6 - A3*X7; y(8) = A4*y(7)-W4*W4*X9; y(9) = X8 - A4*X9; Nonlinearity z e2 z + e F( z) = M z + e1 z e1 + 2 Slide 10 2

11 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 11

12 Frequency Band Plan (1) Power Spectrum, dbm/mhz GPS GHz WLAN, Bluetooth 5 GHz WLAN Freq, GHz FCC Spectrum Mask for UWB Slide 12

13 Frequency Band Plan (2) Operating Frequency: GHz Why Lower Band? Limitation in the technical capabilities of integrated circuit implementation at higher frequency. Limit of low cost ICs beyond 6 GHz. Prevent interference with 5 GHz WLAN band. Use as much bandwidth as possible to maximize the emitted power and follows FCC rules i.e. >500MHz. Can be easily change to use higher band if necessary or when cheap technologies available in the future. Slide 13

14 Frequency Band Plan (3) 4 sub-bands for 4 simultaneously operating piconets (SOPs) Freq, GHz Subband fc, GHz fl, GHz fr, GHz 1 3,35 3,1 3,6 2 3,85 3,6 4,1 3 4,35 4,1 4,6 4 4,85 4,6 5, MHz bandwidth at 10 db Spaced 500 MHz away Freq, GHz Slide 14

15 FCC UWB Emission Mask UWB EIRP Emission Level in dbm Frequency, GHz Slide 15

16 Modulation Schemes Various modulation schemes can be deployed: On-off-keying (OOK) Differential-chaos-shift-keying (DCSK) Pulse-position modulation (PPM) Slide 16

17 Why OOK? Advantages: It has less complexity It has 3 db more energy efficiency than DCSK battery saving Disadvantages: It requires non-zero threshold Slide 17

18 January 2005 Power distribution at 10 m Threshold Estimation Once set, threshold is constant! Power distribution at 20 m Power Power Power distributions at 30 m Constant threshold Slide Power

19 DCC-OOK Transmitter & Receiver Transmitter Receiver Direct Chaos Generator Multipath Channel ( ) 2 Envelope detector Threshold decision Slide 19

20 DCC-OOK Transceiver Architecture (1) MAC 1 7 Baseband Processor ADC TX RF Part 5 RX RF Part 4 SRAM 1; ; Very simple modulation scheme: on-off power supply is used for modulation Additional power saving Slide 20

21 DCC-OOK Transceiver Architecture (2) Transmitter RF Part Chaotic Oscillator Piconet Filter Power Amplifier To switch Receiver RF Part Envelope Detector Piconet Filter LNA From switch Slide 21

22 Signal Waveforms and Spectrum 1.5 Signal of chaotic generator 0 Amplitude Normalized Power Spectral Density Time, t [ns] 4 OOK modulated signal Frequency [GHz] 0 Amplitude Normalized Power Spectral Density Time (s) x Frequency [GHz] Slide 22

23 Data Frame Structure MHR : MAC Header MFR : MAC Footer SHR : Synchronization Header PHR : PHY Header Octets: n 2 MAC Sublayer Frame Control Seq. No. Address Field Data Payload FCS MHR MSDU MFR Octets: PHY Layer Octets: 4 1 Preamble Sequence SFD 1 Frame Length 32 MPDU SHR PHR PSDU 38 PPDU Slide 23

24 Payload Bit Rate (1) PPDU (38 Bytes) Preamble SFD PHR PSDU Bytes 32 Bytes 1 0 bits T s = 100 ns : Pulse emission time T s T m T s T m T m = 400 ns : Pulse bin width or Bit period Duty cycle, D = 1/4 Nominal PHY-SAP payload bit rate, X 0 = (1/400ns) (1000/1024) = 2.44Mbps Slide 24

25 Data Throughput (1) Packet 1 Data Frame 1 (38 bytes) 32 bits ACK (11 bytes) 40 bits Data Frame 2 (38 bytes) t data-frame t ACK t ACK-frame LIFS Time for acknowledged transmission, t packet t packet = t data-frame + t ACK + t ACK-frame + LIFS = ( ns) + (32 400ns) + ( ns) + (40 400ns) = 121.6µs µs µs + 16µs = 185.6µs Nominal Data Throughput, T 0 = (32 8/185.6µs) (1000/1024) = 1.35Mbps Slide 25

26 Payload Bit Rate (2) PPDU (38 Bytes) Preamble SFD PHR PSDU Bytes 32 Bytes 1 0 bits T s = 100 ns : Pulse emission time T s T m T s T m T m = 600 ns : Pulse bin width or Bit period Duty cycle, D = 1/6 Optional PHY-SAP payload bit rate, X i = (1/600ns) (1000/1024) = 1.63Mbps Slide 26

27 Data Throughput (2) Packet 1 Data Frame 1 (38 bytes) 32 bits ACK (11 bytes) 40 bits Data Frame 2 (38 bytes) t data-frame t ACK t ACK-frame LIFS Time for acknowledged transmission, t packet t packet = t data-frame + t ACK + t ACK-frame + LIFS = ( ns) + (32 600ns) + ( ns) + (40 600ns) = 182.4µs µs µs + 24µs = 278.4µs Optional Data Throughput, T i = (32 8/278.4µs) (1000/1024) = 898kbps Slide 27

28 Example of Operation at 1 kbps (1) There are 2 methods of operation in order to achieve 1 kbps data rate: 1. The device transmits several packets in succession, so that the overall data volume is 1kbit i.e bits, then falls silent till the beginning of the next second. 2. The device transmits one packet of data at a time with long pauses between the packets, so that total data volume over 1 second is 1kbit. In the beginning of the next second the device wakes up and transmits another 1kbit portion of data. Slide 28

29 Example of Operation at 1 kbps (2) Packet 1 Packet 2 Packet 3 Packet 4 t packet t idle-1kbps t idle-1kbps t idle-1kbps t idle-1kbps 1024 bits in 1 second To achieve effective data rates of 1 kbps using 32-bytes PSDU, 4 packets need to be transmitted in 1 second. The idle time for the above system is t idle-1kbps 250 ms. Slide 29

30 Data Rates and Range System supports data rates: 1 kbps 10 kbps 1 Mbps 40 kbps (optional) 160 kbps (optional) Aggregated bit rate up to 5 Mbps System supports ranges: Range from 0 to 30 m (typical) Range up to 100 m (max 10 kbps data rate) Slide 30

31 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 31

32 System Simulation Parameters Modulation: OOK Bandwidth: 0.5GHz & 2GHz Pulse bin width, T m : 400ns Pulse emission time, T s : 100ns PSDU length: 32 bytes Slide 32

33 AWGN Performance: BER vs. E b /N OOK Modulation Scheme B=0.5 GHz, uncoded B=2 GHz, uncoded B=0.5 GHz, Hamming (7,4) B=2 GHz, Hamming (7,4) BER E /N, [db] b 0 Slide 33

34 AWGN Performance: PER vs. E b /N OOK Modulation Scheme 10-1 PER B=0.5 GHz, uncoded B=2 GHz, uncoded B=0.5 GHz, Hamming (7,4) B=2 GHz, Hamming (7,4) E /N, [db] b 0 Slide 34

35 Multipath Performance: BER vs. E b /N 0 (1) GHz Bandwidth 10-2 BER AWGN Residential LOS (CM1) Open outdoor LOS (CM5) Industrial NLOS (CM8) E /N, db b 0 Slide 35

36 Multipath Performance: BER vs. E b /N 0 (2) GHz Bandwidth 10-2 BER AWGN Residential LOS (CM1) Open outdoor LOS (CM5) Industrial NLOS (CM8) E /N, db b 0 Slide 36

37 Multipath Performance: PER vs. E b /N 0 (1) GHz Bandwidth 10-1 PER AWGN Residential LOS (CM1) Open outdoor LOS (CM5) Industrial NLOS (CM8) E /N b 0 Slide 37

38 Multipath Performance: PER vs. E b /N 0 (2) GHz Bandwidth 10-1 PER AWGN Residential LOS (CM1) Open outdoor LOS (CM5) Industrial NLOS (CM8) E /N b 0 Slide 38

39 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 39

40 SOP Three methods to achieve SOP: 1. Frequency division multiplexing (FDM) Four independent frequency channels of 500 MHz bandwidth. This guaranties simultaneously operating of four piconets. 2. Code division multiplexing (CDM) Deployed a class of unipolar codes (0,1) having ZCD/LCD property maintain orthogonality among piconets. Four set of codes can support four simultaneously operating piconets. 3. Frequency-code division multiplexing (FCDM) Two independent frequency channels with 1 GHz bandwidth each and within each frequency channel, a set of codes is used similar to CDM technique. Only two set of codes require to support four simultaneously operating piconets. Slide 40

41 SOP: FDM 4 sub-bands for 4 simultaneously operating piconets (SOPs) Freq, GHz Subband fc, GHz fl, GHz fr, GHz 1 3,35 3,1 3,6 2 3,85 3,6 4,1 3 4,35 4,1 4,6 4 4,85 4,6 5, MHz bandwidth at 10 db Spaced 500 MHz away Freq, GHz Slide 41

42 SOP: CDM (1) Deployed a class of unipolar codes (0,1) having ZCD/LCD property to maintain orthogonality among piconets. This type of codes have inter-piconetinterference (IPI) immunity capability, thus can provide interference free scheme to achieve efficient SOP. Using simple modulation and demodulation scheme chaotic-ook with correlator based receiver. Slide 42

43 SOP: CDM (2) Tx1 Tx4 Tx1(Desired user) t Unipolar DATA t Spreading t Unipolar Code1 Unipolar Code4 OOK Modulation Chaotic Source OOK Modulation Unipolar DATA Spreading t Chaotic Source t Radio Channel CDM Code1:Piconet1 Code2:piconet2 Code3:piconet3 Code4:piconet4 t Rx1 t Recovered DATA 1 0 Matched Filter Envelope Detector t Detection Baseband BPF LNA Slide 43

44 SOP: CDM (3) Baseband Implementation in LABVIEW Slide 44

45 SOP: CDM (4) Chaotic Source Generator in LABVIEW Slide 45

46 SOP: FCDM 2 sub-bands and a set of PN code for each sub-bands => 4 simultaneously operating piconets (SOPs) A Set of PN Code Chaotic Source Freq, GHz Freq, GHz Freq, GHz Subband fc, GHz fl, GHz fr, GHz GHz bandwidth for each sub-band. Slide 46

47 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 47

48 Ranging Scheme (1) Ranging circuit contains 2 low frequency generators with slightly different frequency to generate probing pulses, f 0 (2.500 MHz) & reference pulses, f 1 =f 0 + f ( MHz). Circuit also contains 3 counters that count the no. of reference pulses, N3, no. of delayed pulses from the channel, N1 and no. of overlapping pulses, N2. Range is determined from the reading of the 3 counters. Slide 48

49 Ranging Scheme (2) MHz Pulse source delay start both pulse sources & counter N3 20 MHz Clock source MHz Pulse source Overlap detector no 1st delayed pulse? yes N3 N2 N1 start counter N1 Digital Block Counter N1 counts delayed pulses Counter N2 counts overlaps between delayed pulses (f 0 = MHz) and reference pulses (f 1 = MHz) Counter N3 counts reference pulses no no 1st overlap match? yes stop N1 & N3, start N2 last overlap match? yes stop N2, calculate T TOA Slide 49

50 Overlapping of Delayed & Reference Pulses Delayed pulse Reference pulse Overlapped pulse Slide 50

51 Ranging Scheme (3) T TOA N1 N1, N2, N3 Number of pulses С 1 С 2 С 3 N3 N2 t* * T TOA = (N3+0.5 N2)/f 1 (N1+0.5 N2)/f 0 Distance: S = 0.5*c*(T TOA -τ 0 ) t 0 t 1 t 2 t 3 Operation time of counters C 1, C 2, C 3. τ 0 retranslation time Slide 51

52 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 52

53 Power Consumption (1) Transceiver Average power consumption P av Tx Rx CU Control Unit P av = P Tx + P Rx + P CU P Tx = P e / η P Rx = P e / η best Operation time T oper T oper = C b U b / P av P e = P in T e = 1/2 D P in T bit R P e is emitted power, η is efficiency, η best is the best of all possible efficiencies, T bit is duration of one bit, R is transmission rate, C b is battery capacity, P in is instantaneous emission power, T e is time of emission for given transmission rate, U b is battery voltage, D is duty cycle. Slide 53

54 Power Consumption (2) Transmission Rate R, kbps Average Emitted Power P e, mw Average Power Consumption P av (η = 5%) Lifetime of the AAA battery, years µw % duty cycle µw 15 10% duty cycle mw % duty cycle P CU = 7.5 µw ; P in = 4 mw ; η best = 5%; U b = 1.5 V ; C b = 750 mah; Example: R = 1 kbps; T bit = 400 ns; η = 5% D = 1/4 P e = 1/2 D P in T bit R = 0.2 µw P av = P Tx + P Rx + P CU = P e /η + P e /η best + P CU = 15.5 µw Slide 54

55 Power Management Modes Wake Up Structure Wake Up Signal Wake Up Radio Power Detector Main Transceiver / Receiver Slide 55

56 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 56

57 Link Budget & Sensitivity Slide 57

58 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 58

59 RF January 2005 Wake up Sleep Chaotic Generator Transceiver Architecture Piconet Filter Modulator (OOK) information Power Amplifier MAC PHY Baseband (Digital) Counter 3 Probing Generator MHz Reference Generator MHz Antenna Switch Counter 2 Range DSP Block Counter 1 Ranging Architecture Recover Information Low Pass filter Detector ( ) 2 Piconet Filter Low Noise Amplifier Slide 59

60 Unit Manufacturing Cost & Complexity (1) RF part of the transceiver: Chaos oscillator in GHz frequency band with 10 dbm output power amplifier (common complexity is equivalent to 4 power amplifiers) Switch-modulator LNA (amplification db) Tunable filter with bandwidth 500 MHz (in band GHz) Envelope detector Antennas No: mixers, correlators, RF VCO Slide 60

61 Unit Manufacturing Cost & Complexity (2) Baseband part of the transceiver: Reference oscillator 20 MHz Bandpass amplifiers Threshold detector or 4 bit A/D converter Frequency Synthesizer on MHz (for ranging) Digital part with ~ 10K gates Slide 61

62 Size & Form Factor PHY level (130 nm technology) RF part of transceiver < 0.3 mm 2 Analog part of transceiver PHY level baseband < 0.2 mm 2 Digital part of transceiver PHY level baseband < 0.3 mm 2 Common layout square for PHY-level < 1.0 mm 2 Antenna: 2.0 x 2.0 cm 2 Slide 62

63 Technical Feasibility (1) UWB DCC-OOK Test-bed Slide 63

64 Technical Feasibility (2) DCC-OOK Experiment: GHz Slide 64

65 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 65

66 Scaling Parameters Scalability is the tradeoff between Bit rate Power consumption Range Complexity/Cost PHY mechanisms used Transmit power control Dynamic frequency selection Invoked if link quality falls below some threshold Example applications: Home usage/smart home (1kbps - 20 to 30m) Communication and networking (1kbps - 20 to 30m) etc. Slide 66

67 What can be scaled? Power consumption: Bandwidth used Data rate, duty cycle and distance of operation Packet transmission followed by sleep mode Data rate: Scalable from 1 kbps to 1 Mbps Range: Scalable with coding, lower bit duration (up to the optimum value) and power consumption. Complexity: Lower complexity is possible with trade-off of reduced system performance Scale with future CMOS process improvements e.g. use upper frequency band Slide 67

68 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 68

69 Self-Evaluation Criteria Ref. Importance Level Proposer Response Unit Manufacturing Complexity 3.1 A + Technical Feasibility 3.4 A + Scalability 3.5 A + Size and Form Factor 5.2 A + PHY-SAP Payload Bit Rate and Data Throughput A + Simultaneous Operating Piconets 5.4 A + System Performance 5.6 A + Ranging 5.7 A + Link Budget 5.8 A + Sensitivity 5.9 A + Power Management & Modes 5.10 A + Power Consumption 5.11 A + Slide 69

70 Outline Characteristics of Chaotic Signal Principle of Direct Chaotic Communications (DCC) PHY Layer Proposal System Performance Simultaneously Operating Piconets (SOP) Ranging Technique Power Consumption & Power Management Modes Link Budget & Sensitivity Complexity, Cost & Technical Feasibility Scalability Self-Evaluation Conclusion Slide 70

71 Conclusions Chaotic communications meet the low power, low cost & low complexity requirements best suited for 15.4a applications. Proposed DCC-OOK compliant with FCC UWB PSD regulation. Feasibility and scalability are guaranteed with precision ranging and SOP capabilities. The implemented test bed demonstrated that the feasibility of DCC technology. Slide 71

72 DCSK: Compatible Modulation Scheme for Direct Chaotic Communication Slide 72

73 Outline General Overview Characteristics of DCSK Principle of Differential Chaotic Shift Keying (DCSK) Modulation Simultaneously Operating Piconets (SOP) Ranging Technique Scalability Complexity, Cost & Technical Feasibility Link Budget & Sensitivity Conclusion Slide 73

74 General Overview Direct chaotic signal can be applied to the Differential Chaos Shift Keying (DCSK) modulation scheme as an alternative to OOK DCC The Chaotic properties are maintained as in the case of the OOK Slide 74

75 Characteristics of DCSK Direct Chaotic Shift Keying (DCSK) same data rate as in the proposed OOK Constant decision threshold in the receiver SOP can be achieved by transmitting different chaotic pulse length Slide 75

76 Principle of DCSK Modulation(1) DCSK transmits a reference chaotic pulse and an information data pulse depending on whether information bit 1 (same ref. chaotic pulse) or 0 (inverted of the chaotic pulse) is being transmitted The information signal can be recovered by a correlator. Slide 76

77 Principle of DCSK Modulation (2) OOK Vs DCSK OOK DCSK 10-2 BER Eb/No Transmitter Receiver T/2 Integrator T/2 Chaotic Generator Delay T/2-1 Delay T/2 T Threshold Data Bit Stream Slide 77

78 SOP (1) In DCSK SOP can be done using Chaotic Length Division Multiple Access (LDMA). LDMA works based on the exploitation of different chaotic length assigned to each piconets. LDMA is based on the spectral and correlation property of chaotic signal. Slide 78

79 SOP (2) Piconet 1 Piconet 2 Piconet 3 Piconet 4 Piconet 1 User Detection 5 0 Piconet Piconet Piconet Piconet All BER Users 8Mbps 5Mbps S/N Slide 79

80 Chaotic DCSK Correlation Property SOP (3) Chaotic Tx Rx Source D or Σ Data Bit Stream -1 D d D = Constant, d = Variable Variable Delay d Slide 80

81 Ranging Technique Ranging technique used is the same as OOK proposal. Slide 81

82 Scalability (1) Scalability can be achieved using Chaotic gain Varying bit duration Duty cycle Repeated transmission of information bearing chip. Slide 82

83 Scalability (2) Bit = nsec 1 Chaotic Gain in DCSK 5 Mbps Gain 5Mbps 4Mbps 2Mbps 250 nsec Mbps 0 BER nsec 5 1 Mbps S/N Slide 83

84 10 0 Scalability (3) Scalability: varying bit duration Error Probability T T Bit duration Repeated transmission Mbps, 12dB 1Mbps,10dB 5Mbps, 10dB 1Mbps, 12dB Processing Gain T Duty Cycle Slide 84

85 Complexity, Cost & Technical Feasibility Complexity and cost will be slightly higher compare to the OOK chaotic system proposed Slide 85

86 Link Budget & Sensitivity Parameter Throughput (R b ), Kbps Duty cyrcle, db Average Tx Power (P T ), dbm Geometric central frequency Fc, GHz Path loss at 1 m (L 1 ), db Path loss at 30 m (L 2 ), db Tx antenna gain (G T ), db Rx antenna gain (G R ), db Rx Power at 30 m (P R =P T +G T +G R -L 1 -L 2 ), dbm Average noise power per bit (N= *log 10 (R b )), dbm Rx noise figure referred to the antenna terminal (N F ), db Total average noise power per bit (P N =N+N F ), dbm Minimum Eb/No (S), db Raw bit rate, kbps Code rate Implementation loss (I), db Link Margin at 30 m (M=P R -P N -S-I), db Rx sensitivity level, db Value Value Slide 86

87 Conclusion Chaotic communication based on DCSK modulation is an alternative solution. SOP and ranging can also be solved using DCSK. Hardware complexity is slightly higher than OOK since most hardware from OOK is retained. Slide 87

88 Backup Slides Slide 88

89 Tolerance of Components (1) Tolerance of the components of the chaotic oscillator with insignificant changes of spectral properties are from 5%-20% for different components. However, it is possible to develop a chaotic oscillator with better tolerance of components. Slide 89

90 Tolerance of Components (2) C BFP620 X3 L L10 C L=L C17 C=C1 C C20 C=100 pf R RL1 R=RL Vampin Vampout Vout DT DA_LCBandpassDT1_colp_collector_amp_f lt v a_hp_mga-66100_ DA_LCBandpassDT1 Amp1 Fs1=2 GHz V_DC Fp1=3.1 GHz V_DC SRC2 Fp2=5.1 GHz SRC1 Vdc=VE Fs2=6 GHz Vdc=VC Ap=3 db C As=40 db C16 N=4 C=C2 R ResponseTy pe=elliptic RE1 Rg=50 Ohm R=RE Rl=50 Ohm R R12 R=50 Ohm E Capacitor, C1 and inductance, L 20% tolerance. C2 and resistors, RE and R1 5% tolerance. Slide 90

91 Summary of Features Information carrier Band division Channel bandwidth Pulse duration Chaotic radio pulses 3 bands within FCC Mask ( , and GHz) 2.0 GHz band or 4 channels with 500 MHz in each in the 2 GHz band 400 ns Individual bit rate 1 Kbps 10 Kbps 100 Kbps Transmit power -30 dbm -20 dbm -20 dbm 2.5 year 2.5 year 2.5 year Battery life 100% duty cycle 10% duty cycle 0.1% duty cycle Aggregated bit rate Up to 5 Mbps Slide 91

92 Tiny Chaos Transmitter for Wireless Communications Transmitter consists of: - chaos generator - modulator - antenna Frequency band GHz Radiating power mw Slide 92