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Ultra-wideband (UWB) Signals for Communications and Localization. Sinan Gezici Assistant Professor Dept. of Electrical and Electronics Eng. Bilkent University gezici@ee.bilkent.edu.tr. Ultra-wideband (UWB). Definition (Absolute) bandwidth ≥ 500 MHz B abs = f H – f L
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Ultra-wideband (UWB) Signals for Communications and Localization Sinan Gezici Assistant Professor Dept. of Electrical and Electronics Eng. Bilkent University gezici@ee.bilkent.edu.tr
Ultra-wideband (UWB) • Definition • (Absolute) bandwidth ≥ 500 MHz Babs = fH– fL • Fractional bandwidth ≥ 0.2 Bfrac = (fH– fL) / fC≥ 0.2
Regulations for UWB • FCC in the US allows transmission in 3.1-10.6 GHz band • Coexists with incumbent systems • Low power spectral density (-41.3 dBm/MHz) • Large spreading factors UWB
UWB Signals • 3 common signaling formats: • OFDM UWB • DS-CDMA UWB • Impulse radio (IR) UWB A train of short duration (sub-nanosecond) pulses with a low duty cycle One information symbol
Advantages of UWB (1/2) For AWGN channels • High data rate: Large bandwidth increases capacity • Low power/cost: Simple transceiver architectures with low power consumption are possible
Advantages of UWB (2/2) Time=T1 Transmitted Signal Object Radar Transceiver • Precise position estimation (localization): High time resolution Time=T2 Reflected Signal Device Object Range = 0.5(T2-T1)cc : Speed of light 15 m • Penetration through obstacles: Large frequency band facilitates penetration through objects • Low probability of detection: Similar to white noise for other systems http://www.radarvision.com
Applications (1/2) • Communications • High data rate: e.g. wireless USB, WPAN • Low data rate: IEEE 802.15.4a, wireless sensor networks http://www.soumu.go.jp
Applications (2/2) [E. M. Staderini 2002] • Radar and localization http://www.radarvision.com Other applications: e.g., thru-wall monitoring, rescue operations after an earthquake. Medical applications: e.g., non-invasive patient monitoring, respiration and heartbeat rate estimation