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XtremeSpectrum Inc. IEEE Wireless Communications and Networking Conference (WCNC‘2003) Enabling Wireless Multimedia. John McCorkle CTO John@XtremeSpectrum.com. Ultra-Wideband: A New Wireless Technology. A military technology transitioning to the commercial market Simultaneous delivery of
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XtremeSpectrum Inc. IEEE Wireless Communications and Networking Conference (WCNC‘2003)Enabling Wireless Multimedia John McCorkleCTOJohn@XtremeSpectrum.com
Ultra-Wideband:A New Wireless Technology • A military technology transitioning to the commercial market • Simultaneous delivery of • High Data Rate • Low Power – Long Battery Life • Low Cost • FCC approved on February 14, 2002: 3.1-10.6 GHz IEEE Wireless Communications and Networking Conference (WCNC'2003), 19Mar03
UWB - A Unique Opportunity • A fundamental change in this allocation of spectrum • Wide low-power versus narrow high-power • Requires new thought as to the utilization of this allocation(don’t be entrapped by legacy narrowband approaches) • A technology who’s fundamental benefits come from the unique nature of wide bandwidth transmissions within multipath • Capturing these benefits requires a move away from legacy incoherent frequency division and toward wide fully coherent processing. • A market opportunity that changes the fundamental tradeoffs of performance vs. cost/power consumption • Bluetooth price, but speed and QoS beyond 802.11a,g • An intersection of PC and CE products (inc. mobile telephony) IEEE Wireless Communications and Networking Conference (WCNC'2003), 19Mar03
Fundamental Issues • Multi-user performance • Consumer usage means pervasive horizontal deployment • Simultaneous full rate support • Each user will want to take full advantage of the maximum rate supported with high QOS in multipath • Spectral Flexibility and Scalability • For new regulatory environments on a worldwide basis • Modifications to existing rules • Narrowband Interference avoidance/mitigation • For existing systems (UNII band) and new narrowband allocations IEEE Wireless Communications and Networking Conference (WCNC'2003), 19Mar03
Full Rate SupportFor Multiple Overlapping Piconets • High aggregate rates in multipath • Modulation choice for low SNR - Efficiency is key in two domains • Constellation with greatest distance between points – Lowest SNR • Scalability - High ratio of incremental performance versus hardware complexity/power • BPSK & QPSK with M-BOK provide both • Multiple Access Techniques • CDMA (Maximize coding on all radiated energy) • FDMA (Effective for extreme situations • back to back TV sharing a wall between two apartments) • TDMA within a piconet (QoS guarantee) IEEE Wireless Communications and Networking Conference (WCNC'2003), 19Mar03
Low Band High Band 3 4 5 6 7 8 9 10 11 3 4 5 6 7 8 9 10 11 Multi-Band 3 4 5 6 7 8 9 10 11 Three Spectral Modes of Operation • Low Band (3.1 to 5.15 GHz) • 28.5 Mbps to 400 Mbps • 4 piconets give 1.6 Gbps aggregate • High Band (5.825 to 10.6 GHz) • 57 Mbps to 800 Mbps • 4 piconets give 3.2 Gbps aggregate • Multi-Band (3.1 to 5.15 GHz plus 5.825 GHz to 10.6 GHz) • Up to 1.2 Gbps per piconet – 4.8 Gbps aggregate • Full Duplex Mode • Frequency Division Multiplexing (FDM) Mode • Wide gap gives >60 dB isolation • Allows nodes in neighboring piconets to be inches apart • Wide 50% coherent bandwidth in each band derives benefits of UWB in high multipath • Small multipath dips, small link margin requirements • Many paths resolved, very robust --multiple paths exist that can make the link work • Processing gain versus narrowband interference IEEE Wireless Communications and Networking Conference (WCNC'2003), 19Mar03
Spectral Flexibility & Scalability • New bands easy to add • Clear Channel Assessment Capability Allows All MAC modes and simple scaleable management • Processing gain against narrowband interference – 6dB lo-band, 9dB hi-band rel. to 500MHz BW bands • Bandwidth programmable with current-controlled cut-off frequency Low Pass filter • Center frequency programmable with PLL Example 1: Modified Low Band to include protection for 4.9-5.0 GHz WLAN Band Example 2: Support for hypothetical “above 6 GHz only” UWB definition 3 4 5 6 3 4 5 6 3 4 5 6 7 8 9 10 11 IEEE Wireless Communications and Networking Conference (WCNC'2003), 19Mar03
0 1 -5 -10 0.5 dB -15 -20 0 -25 -30 -0.5 -35 GHz -40 -1 3 4 5 6 7 8 9 10 11 1 -1 0 1 0 LongWavelet Low Peak Volts 0.5 -5 -10 0 -15 dB -20 -25 -0.5 Works on 90nm and smaller CMOS without a Power Amp -30 Mid Wavelet -35 -1 GHz -1 0 1 -40 3 4 5 6 7 8 9 10 11 1 0 -5 dB -10 0.5 -15 CombinedWavelet(Both) -20 0 -25 -30 -0.5 -35 GHz -40 -1 3 4 5 6 7 8 9 10 11 -1 0 1 Air Interface Is A SimpleJoint Time Frequency Wavelet Family • Easy-to-make short-time (1-chip period) pulses give 60 dB FDM isolation due to wide gap between bands • Widest contiguous bands – Getting highest coding gain possible maximizes performance in many dimensions • FDM, Processing gain against RFI, Coding gain for overlapping piconets in multipath, simpler silicon • Highest performance for lowest bill of materials cost IEEE Wireless Communications and Networking Conference (WCNC'2003), 19Mar03