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Introduction to Ultra WideBand Sy stems Chia-Hsin Cheng
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Introduction to UWB

Apr 22, 2015

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Introduction to Ultra WideBand Systems Chia-Hsin Cheng Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Outlines Introduction The history of UWB UWB Regulations (FCC Rules) UWB signals UWB in IEEE 802 Standards The Application of UWB Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Introduction The world of ultra wideband (UWB) has changed dramatically in very recent history. In the past 20 years, UWB was used for radar, sensing, military communications and niche applications. A substantial change occurred in February 2002, when the FCC (2002a,b) issued a ruling that UWB could be used for data communications as well as for radar and safety applications. Recently, UWB technology has been focused on consumer electronics and communications. Ideal targets for UWB systems are low power, low cost, high data rates, precise positioning capability and extremely low interference. Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. UWB transmitter signal BW: Or, BW > 500 MHz regardless of fractional BW UWB Transmitter Defined fu-fl fu+fl 2 > 0.20 Where: fu= upper 10 dB down point fl = lower 10 dB down point Source: US 47 CFR Part15 Ultra-Wideband Operations FCC Report and Order, 22 April 2002: http://www.fcc.gov/Bureaus/Engineering_Technology/Orders/2002/fcc02048.pdf Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. UWB: Large Fractional Bandwidth Power Spectral Density (dB) one chip CDMA: 1.288Mcps/1.8 GHz 0.07% bandwidth 6% bandwidth -80 -40 0 Frequency (GHz) 3 6 9 12 15 Random noise signal 100% bandwidth UWB NB 20% bandwidth Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Large Relative (and Absolute) Bandwidth UWB is a form of extremely wide spread spectrum where RF energy is spread over gigahertz of spectrum Wider than any narrowband system by orders of magnitude Power seen by a narrowband system is a fraction of the total UWB signals can be designed to look like imperceptible random noise to conventional radios Narrowband (30kHz) Wideband CDMA (5 MHz) UWB (Several GHz) Frequency Part 15 Limit ( -41.3dBm/Hz ) Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Why is Ultra Wideband So Effective? Shannon showed that the system capacity, C, of a channel perturbed by AWGN --- ) 1 ( log2NSB C + =Where: C = Max Channel Capacity (bits/sec) B = Channel Bandwidth (Hz) S = Signal Power (watts) N = Noise Power (watts) Capacity per channel (bps) B Capacity per channel (bps) log(1+S/N) 1. Increase B 2. Increase S/N, use higher order modulation 3. Increase number of channels using spatial separation (e.g., MIMO) Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Throughput Low Power UWB Comparable to High Power Wireless Systems UWB throughput between 802.11a and b Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. UWB Properties Extremely difficult to detect by unintended users Highly Secured Non-interfering to other communication systems It appears like noise for other systems Both Line of Sight and non-Line of Sight operation Can pass through walls and doors High multipath immunity Common architecture for communications, radar & positioning (software re-definable) Low cost, low power, nearly all-digital and single chip architecture Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Outlines Introduction The history of UWB UWB Regulations (FCC Rules) UWB signals UWB in IEEE 802 Standards The Application of UWB Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. The history of UWB Technology Before 1900: Wireless Began as UWB Large RF bandwidths, but did not take advantage of large spreading gain 1900-40s: Wireless goes tuned Analog processing: filters, resonators Separation of services by wavelength Era of wireless telephony begins: AM / SSB / FM Commercial broadcasting matures, radar and signal processing 1970-90s: Digital techniques applied to UWB Wide band impulse radar Allows for realization of the HUGE available spreading gain Now: UWB approved by FCC for commercialization For further details, refer to ref.[1] Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. What UWB is Today 7,500 MHz available spectrum for unlicensed use US operating frequency: 3,100 10,600 MHz Emission limit: -41.3dBm/MHz EIRP Indoor and handheld systems Other restrictions and measurement procedures in Report and Order UWB transmitter defined as having the lesser of Fractional bandwidth greater than 20% Occupies more than 500 MHz UWB is NOT defined in terms of Modulation or Carrierless or Impulse radio Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Outlines Introduction The history of UWB UWB Regulations (FCC Rules) UWB signals UWB in IEEE 802 Standards The Application of UWB Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Summary of the FCC Rules Significant protection provided for sensitive systems GPS, Federal aviation systems, etc. Lowest emission limits ever by FCC Incorporates NTIA (National Telecomm. and Info. Administration) recommendations Allows UWB technology to coexist with existing radio services without causing interference FCC opened up new spectrum for UWB transmissions One of the bands is from 3.1GHz to 10.6GHz Maximum power emission limit is - 41.3dBm/MHz Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. FCC UWB Device Classifications Report and Order authorizes 5 classes of devices with different limits for each: Imaging Systems Ground penetrating radars, wall imaging, medical imaging Thru-wall Imaging & Surveillance Systems Communication and Measurement Systems Indoor Systems Hand-held Systems Vehicular Radar Systems collision avoidance, improved airbag activation, suspension systems, etc. Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. FCC First Report and Order Authorizes Five Types of Devices Class / Application Frequency Band for Operation at Part 15 Limits User Limitations Communications and Measurement Systems 3.1 to 10.6 GHz (different out-of-band emission limits for indoor and hand-held devices) No Imaging: Ground Penetrating Radar, Wall, Medical Imaging

= = = = =3 . .symbol data per pulses of number :4 . .4 period code2 , ] 2 0 0 1 [ codeword( ) ( )10 sNstr tr s f iN j c ii jS t w t iT jT c T d o+== =1idWireless Access Tech. Lab. CCU Wireless Access Tech. Lab. DS-UWB DS-UWB 10( ) ( )cNtr i n b ci ns t d a w t iT nT== =1id =>= -1id =>Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Multiband UWB Refer to OFDM course Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Outlines Introduction The history of UWB UWB Regulations (FCC Rules) UWB signals UWB in IEEE 802 Standards The Application of UWB Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. UWB in IEEE 802 Standards IEEE 802 Organization IEEE 802.15.3a IEEE 802.15.4a Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. WLAN IEEE 802.11 WPAN IEEE 802.15 WMAN IEEE 802.16 802.15.1 Bluetooth 802.15.3 High Data Rate MAC & 2.4 GHz PHY Task Group 3a Alt PHY (UWB) 802.15.4 Zigbee 2.4 GHz LAN/MAN Standards Committee (Wireless Areas) 802.15.2 Coexistence IEEE 802 Organization MBWA IEEE 802.20 Regulatory TAG IEEE 802.18 Coexistence TAG IEEE 802.19 Based on: Overview of 802.15.3 and 3a, R. F. Heile, Workshop on Current Developments in UWB, Institute for Infocomm Research, Singapore Study Group 4a (UWB?) Mini-Glossary: WLAN-wireless Local Area Network; MAN-Metropolitan Area Network; TAG-Technical Advisory Group;-MBWA-Mobile Broadband Wireless Access Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. IEEE Project 802 Local and Metropolitan Area Network Standards Committee Accredited by ANSI, Sponsored by IEEE Computer Society Ethernet, Token Ring, Wireless, Cable Modem Standards Bridging, VLAN, Security Standards Meets three times per year (400-600 individuals, 15% non-US) Develops equivalent IEC/ISO JTC 1 standards JTC 1 series of equivalent standards are ISO 8802-nnn IEEE URLs 802 http://grouper.ieee.org/groups/802/ 802.15 http://grouper.ieee.org/groups/802/15/ Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Standards : Range and Data Rate Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. UWB Technique OFDM TDMS/FDMA Pulses DSSS/CDMA Bands 3 to 13 3 to 13 2 Bandwidths 528 MHz 550 MHz 1.368 GHz, 2.736 GHz Frequency ranges 3.168 GHz 4.752 GHz 4.752 10.296 3.325 GHz 4.975 GHz, 4.975 GHz 10.475 GHz 3.1 GHz 5.15 GHz 5.825 GHz 10.6 GHz Modulation Scheme OFDM, QPSK M-ary Bi-Orthogonal Keying (M-BOK), QPSK BPSK, QPSK, M-BOK Error correction Convolutional code Convolutional code, Reed-Solomon code Convolutional code, Reed-Solomon code Code rates 11/32 rate at 110 Mbps, 5/8 rate at 200 Mbps, rate at 480 Mbps 6/32 rate at 110 Mbps, 5/16 rate at 200 Mbps, rate at 480 Mbps rate at 110 Mbps, RS(255,223) at 200 Mbps, RS(255,223) t 480 Mbps Link margin 5.3/6 dB at 10 m / 110 Mbps, 10.7 dB at 4 m / 200 Mbps, 6.2 dB at 4 m / 480 Mbps 6.3 dB at 10 m / 108 Mbps, 8.0 dB at 4 m / 288 Mbps, 4.0 dB at 4 m / 577 Mbps 6.1 dB at 10 m / 110 Mbps, 11.1 dB at 4 m / 200 Mbps, 6.1 dB at 4 m / 600 Mbps Symbol period 312.5 ns OFDM symbol 3 ns 23 or 17.5 ns (Low band), 11.7 or 8.9 ns (High band) Multipath mitigation method 1-tap (robust to 60.6 ns delay spread) frequency interleaving of MBOK chips; time frequency codes; feed forward filter Decision feedback equalizer Candidate UWB Systems Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. 802.15.3a high data rate WPAN standard Direct sequence (DS-UWB) Championed by Motorola/XtremeSpectrum Classic UWB, simple pulses, 2 frequency bands: 3.1-4.85GHz, 6.2-9.7GHz CDMA has been proposed at the encoding layer Spectrum dependent on the shaping filter possible differing devices worldwide Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) Intel/TI/many others Similar in nature to 802.11a/g 14 528MHz bands (simplest devices need to support 3 lowest bands, 3.1GHz 4.7 GHz) Spectrum shaping flexibility for international use Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Detail of DS-CDMA Candidate for 802.15.3a Multi-band DS-CDMA Physical Layer Proposal Summary from IEEE document 15-03-0334-02-003a-Merger-2-CFP-Presentation.ppt Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. 3 4 5 6 7 8 9 10 11 High Band 3 4 5 6 7 8 9 10 11 Low Band 3 4 5 6 7 8 9 10 11 Multi-Band With an appropriate diplexer, the multi-band mode will support full-duplex operation (RX in one band while TX in the other) Low Band (3.1 to 5.15 GHz) 25 Mbps to 450 Mbps High Band (5.825 to 10.6 GHz) 25 Mbps to 900 Mbps Multi-Band (3.1 to 5.15 GHz plus 5.825 GHz to 10.6 GHz) Up to 1.35 Gbps Two Band DS-CDMA 3 Spectral Modes of Operation Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Joint Time Frequency Wavelet Family Example Duplex Wavelet Mid Wavelet Long Wavelet 3 4 5 6 7 8 9 10 11 -40 -35 -30 -25 -20 -15 -10 -5 0 GHz dB 3 4 5 6 7 8 9 10 11 -40 -35 -30 -25 -20 -15 -10 -5 0 GHz dB 3 4 5 6 7 8 9 10 11 -40 -35 -30 -25 -20 -15 -10 -5 0 GHz dB -1 0 1 -1 -0.5 0 0.5 1 -1 0 1 -1 -0.5 0 0.5 1 -1 0 1 -1 -0.5 0 0.5 1 Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. PHY Proposal accommodates alternate spectral allocations Center frequency and bandwidth are adjustable Supports future spectral allocations Maintains UWB advantages (i.e. wide bandwidth for multipath resolution) No changes to silicon Example 1: Modified Low Band to include protection for 4.9-5.0 GHz WLAN Band 3 4 5 6 3 4 5 6 3 4 5 6 7 8 9 10 11 Example 2: Support for hypothetical above 6 GHz UWB definition Note 1: Reference doc IEEE802.15-03/211 Spectral Flexibility and Scalability Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Detail of OFDM Candidate for 802.15.3a Multi-band OFDM Physical Layer Proposal Summary from IEEE document 03267r1P802-15_TG3a-Multi-band-OFDM-CFP-Presentation.ppt Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Overview of Multi-band OFDM Basic idea: divide spectrum into several 528 MHz bands. Information is transmitted using OFDM modulation on each band. OFDM carriers are efficiently generated using an 128-point IFFT/FFT. Internal precision is reduced by limiting the constellation size to QPSK. Information bits are interleaved across all bands to exploit frequency diversity and provide robustness against multi-path and interference. 60.6 ns cyclic prefix provides robustness against multi-path even in the worst channel environments. 9.5 ns guard interval provides sufficient time for switching between bands. Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Multi-band OFDM: TX Architecture Block diagram of an example TX architecture: Architecture is similar to that of a conventional and proven OFDM system. Can leverage existing OFDM solutions for the development of the Multi-band OFDM physical layer. For a given superframe, the time-frequency code is specified in the beacon by the PNC (PicoNet Controller). The time-frequency code is changed from one superframe to another in order to randomize multi-piconet interference. DAC ScramblerConvolutionalEncoderPuncturerBitInterleaverConstellationMappingIFFTInsert PilotsAdd CP & GITime-Frequency Codeexp(j2tfct)InputDataWireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Band Plan Group the 528 MHz bands into 4 distinct groups Group A: Intended for 1st generation devices (3.1 4.9 GHz) Group B: Reserved for future use (4.9 6.0 GHz) Group C: Intended for devices with improved SOP performance (6.0 8.1 GHz) Group D: Reserved for future use (8.1 10.6 GHz) f3432MHz3960MHz4488MHz5016MHz5808MHz6336MHz6864MHz7392MHz7920MHz8448MHz8976MHz9504MHz10032MHzBand#1Band#2Band#3Band#4Band#5Band#6Band#7Band#8Band#9Band#10Band#11Band#12Band#13GROUP AGROUP BGROUP C GROUP DWireless Access Tech. Lab. CCU Wireless Access Tech. Lab. 802.15.4a alternate PHY for 802.15.4 Addresses the following Globally deployable Compatible / interoperable with 802.15.4 Longer range Higher reliability Ranging/localization support Lower latency & support for mobility Low cost Current UWB systems not quite suitable 90 nm CMOS is expensive, 200 mW is a lot of power Still in early stages Proposals due Jan. 2005! DS-UWB a major contender (Motorola) Chirp Spread Spectrum another cool tech (Nanotron) Many axes for diversity: Basic tech (2.4 v. UWB), ranging (UWB v. CSS v. Phase-based ranging), pulse shapes, channel arbitration (CSMA v. CDMA) Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Outlines Introduction The history of UWB UWB Regulations (FCC Rules) UWB signals Standards of IEEE 802 The Application of UWB Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. The Application of UWB Ultra-wideband is the contortionist of the wireless world it is flexible enough to work in many different ways while still maintaining its character. These applications are distributed amongst three categories: Communications and sensors Position location and tracking Radar Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. The Application of UWB Single and multi-family dwelling residents who have at least one of the following configurations in their dwellings: Source: doc.: IEEE 802.15-01/036r0 Remote control for: Multimedia PC with interactive gaming options Consumer devices like,TV (w internet access), Home Theatre, video gaming console, DVD player, STB, DVCR, Home Stereo, TiVo Interconnectivity between devices (Tomoguchis, Gameboys, etc.) Home security, home automation or HVAC systems (sensors, control units) Illumination control (light switches, spot light control) Small Office/Home Office (SOHO) control of: multimedia presentations conference rooms training rooms automation or control functions Industry applications for control and surveillance Healthcare industry for monitoring and wearable sensors, patient monitoring Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Source: Walter Hirt, Dennis L. Moeller, "The Global View of a Wireless System Integrator," International Symposium on Advanced Radio Technologies (ISART), Boulder, CO, USA, 4-6 March 2002 Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. POTENTIAL FOR UWB 3G and beyond Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Hot-spot Wireless Personal Area Network (WPAN) Intelligent Wireless Area Network (IWAN) Sensor, Positioning, and Identification Network (SPIN) Wireless Body Area Network (WBAN) Outdoor Peer-to-Peer Networking (OPPN) Potential Application Scenarios Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. UWB Consumer Applications Home Entertainment Mobile Devices Computing Automotive Freescale Semi. Wireless Access Tech. Lab. CCU Wireless Access Tech. Lab. Entertainment Applications Connect between sources and displays Drivers are wire elimination for install and freedom of component placement Requirements Bandwidth Each MPEG2 HD Stream 20-29 Mbps Two full rate streams required for PIP Handheld can be used for PIP viewing or channel surfing (SD stream) Range Media center to display or handheld Anywhere in the room (

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