March 3 2003 doc IEEE 802 15 03147

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Project: IEEE P 802. 15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Multicarrier-UWB] Date Submitted: [3 March 2003] Source: [Ahmed H Tewfik] Company [University of Minnesota] Address [Dept. of Electrical and Computer Engineering, Room 4 -174 EECS Bldg. , Minneapolis, MN 55455] Voice: [612 -625 -6024], FAX: [612 -625 -4583], E-Mail: [tewfik@ece. umn. edu] Re: [n/a] Response to a Call for Contributions Task Group 3 a Call For Intent and Proposals, November 2002, updated January 2003, 02371 r 0 P 802 -15_SG 3 a-5_Criteria. doc Abstract: [We propose a multi-carrier UWB system for WPAN communications. We describe system design issues and proposed transmitter and receiver structures. We also provide a self-evaluation of the proposed system. ] Purpose: [For consideration by 802. 15. 3 a task group. ] Notice: This document has been prepared to assist the IEEE P 802. 15. 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 802. 15. Submission 1 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Multicarrier-UWB A. H. Tewfik and E. Saberinia B. University of Minnesota Submission 2 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Overview • • • Unified view of UWB Multicarrier-UWB Proposed system N-tone sigma-delta modulators Self-evaluation Submission 3 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Unified View of UWB • General form Info. signal x • Special cases – TM-UWB – DS-UWB pulse train u. Tp(t) – MC-UWB Tp Submission 4 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Unified View of UWB Info. signal x x pulse train FH or DS Spreading sequence • Advantageous to view p(t) as: p(t)= [pulse train]x[spreading sequence] Submission 5 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Desirable Attributes Baseband signal replicas around Fourier components at fk= k/T Shaping due to s(t) pulse train x Info. signal u(t) 1/NT NT 1/T • Replication in time and frequency domains needed for reliable communications • Poor spectral use – Spectral gaps – Spectral shaping due to S(f) Submission 6 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Desirable Attributes Fill the gaps between spectral lines at fk= k/T Shaping due to s(t) pulse train x Info. signal u(t) 1/NT NT 1/T • Fill the gaps between the spectral lines Submission 7 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Desirable Attributes MC-UWB Submission Matched filter channel 8 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Desirable Attributes • Ambiguity function of p(t) • Would like: Cp(t, f) 0 except for the origin (t, f) =(0, 0) Submission 9 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Multicarrier UWB • Elemental signal • c(n): Costas’ sequence • Time resolution: Tc/N • Frequency resolution: 1/NT Submission 10 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Multicarrier UWB • Advantages – Good time and frequency resolution – Time resolution decoupled from • elementary pulse duration • inter-pulse separation More flexibility for design Submission 11 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Design Approach • Select elementary pulse duration based on peak power and pulse length limitations and desired sidelobe behavior in frequency domain • Select inter-pulse separation and number of pulse based on channel spread and average power limitation • Select TC to fill available bandwidth Submission 12 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Proposed System MC-UWB signal data TCM-QAM 10 tone IFFT 1 bit D/A x • System parameters: – N=30, T=9 nsec, Ts=1 nsec, Tc=4. 5 nsec – 8 subcarriers with TCM 32 -ary QAM – 2 Pilots Submission 13 Modulation: Carrier + FH spreading Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Transmitter Re( ) TCMQAM N-Tone S -D FH c(n) I FF T X VCO S p/2 N-Tone S -D Im( ) Submission 1 bit D/A 14 1 bit D/A X Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Proposed System Demodulator 1 bit A/D 10 tone FFT Costas sequence modulated filterbank Pilot correlation Decision AGC S data Submission 15 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Traditional Sigma Delta X(n) + 1 bit quantizer + - Submission 16 y(n) Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Traditional Sigma Delta D/A X(t) + oversample 1 bit quantizer + - Lowpass Filtering and downsampling Multibit X(n) Analog switched capacitor implementation Submission 17 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Traditional Sigma Delta D/A X(n) + L upsample + 1 bit quantizer 1 bit D/A Analog Lowpass Filtering - X(t) • Higher order SD preferred: – Better noise shaping – Eliminate spurious 18 tones Submission Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> N Tone Sigma Delta X(n) (e. g. , output of N point IFFT) Submission + 1 bit quantizer + - 19 y(n) Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> N Tone Sigma Delta “Instantaneous” Frequency spectrum Filter outputs Submission 20 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> N Tone Sigma Delta Submission Average Frequency spectrum 21 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Multiple Piconets • Simultaneous operation achieved by proper selection of: – Pulse train p(t) • Costas sequence c(n) • Time hopping – Carrier frequencies Submission 22 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Self-Evaluation Submission 23 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Self-Evaluation Submission 24 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Self-Evaluation Submission 25 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Self-Evaluation Submission 26 Tewfik/Saberinia, U. of MN

March 3, 2003 doc. : IEEE 802. 15 -<03147 r 0> Conclusion • Multi-carrier UWB offers ability to use traditional baseband modulation schemes and achieve desired performance • Implementation simplified by use of Ntone sigma-delta modulators Submission 27 Tewfik/Saberinia, U. of MN