January 2005 doc IEEE 802 15 04704 r

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January 2005 doc. : IEEE 802. 15 -04/704 r 1 Project: IEEE P 802.

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Project: IEEE P 802. 15 Working Group for Wireless Personal Area Networks (WPANS) Submission Title: [Staccato UWB PHY Proposal for TG 4 a] Date Submitted: [January 2005] Revised: [] Source: [Roberto Aiello, Ph. D. , Torbjorn Larsson, Ph. D. ] Company [Staccato Communications] E-mail [roberto@staccatocommunications. com] Re: [802. 15. 4 a Call for proposal] Abstract: [This presentation represents Staccato Communication’s proposal for the 802. 15. 4 a PHY standard, based on UWB] Purpose: [Response to WPAN-802. 15. 4 a Call for Proposals] 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 or organization. The material in this document is subject to change in form and content after further study. The contributor reserves 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. 1 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Staccato Communications UWB PHY

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Staccato Communications UWB PHY Proposal for TG 4 a Roberto Aiello, Ph. D. Torbjorn Larsson, Ph. D. Staccato Communications r@staccatocommunications. com Submission 2 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Goals • Good use

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Goals • Good use of UWB unlicensed spectrum • Good system design • Path to low complexity CMOS design • Path to low power consumption • Scalable to future standards • Graceful co-existence with other services • Graceful co-existence with other UWB systems Submission 3 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Introduction • Staccato is

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Introduction • Staccato is MBOA’s founding member, promoter BOD member • This proposal is based on band limited impulse radio • OFDM is optimal solution for high performance systems • Impulse radio has attractive features for 15. 4 a applications Submission 4 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Features • Meets all

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Features • Meets all system requirements • Low signal repetition frequency to reduce ICI/ISI and need for high speed digital circuits (lower power consumption) • “Narrow” UWB bandwidth to reduce complexity • Use of differential encoding on chip level to reduce receiver complexity and provide maximum robustness Submission 5 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Summary • Band limited

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Summary • Band limited UWB system compliant with FCC 02 -48, UWB Report & Order • 500 MHz bandwidth at -10 d. B • Two bands centered at 4. 752 GHz and 5. 252 GHz (MB-OFDM band 4 and 5) • Symbol rates varying from 12. 5 kbps to 1. 6 Mbps at PHY-SAP • Due to time constraints, this presentation addresses – Modulation scheme, channelization and packet structure – Performance in AWGN • Remaining material will be presented at the next opportunity in March 2005 – – Performance in multipath Implementation feasibility Self evaluation criteria Other issues that will emerge from group’s feedback Submission 6 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Multipath CM 8 (Industrial

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Multipath CM 8 (Industrial NLOS) PRF = 3. 2 MHz Submission 7 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Description PRF =

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Description PRF = 3. 2 MHz Submission 8 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Description, Continued •

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Description, Continued • Impulse radio combined with direct-sequence spreading • Differential BPSK modulation of chips • A code word covers one BPSK-modulated symbol • Different piconets use different code words • Differential encoding of chips allows the use of differential chip detection in the receiver – Differential detection is carried out separately for each multipath component – Differential combining of multipath components – No need for channel estimation – Simple receiver structure with decent performance Submission 9 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Description, Continued •

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Description, Continued • For improved performance, non-coherent symbol detection (with coherent energy integration across one code word) can be used – Symbol detection is carried out separately for each multipath component – Non-coherent combining of multipath components – Still no need for channel estimation • PRF (chip rate): 3. 2 MHz – Low enough to avoid interchip interference (ICI) with all 802. 15. 4 a multipath models – High enough to eliminate the need for frequency offset correction (with some performance loss) when differential detection is used • Pulse shape: 3 rd-order Butterworth or similar • FEC: 16 -state rate-1/2 convolutional code and symbol repetition Submission 10 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Differential Multipath Combining Submission

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Differential Multipath Combining Submission 11 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Parameters PHR =

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Parameters PHR = PHY Header; PSDU = PHY Service Data Unit; SFD = Start-of-Frame Delimiter • Length of spreading code in preamble is always 16 • Duty cycle < 100% means that code words of length 16 are transmitted with a space in between – An extra initial chip is added to serve as phase reference for the first chip in the code word – For instance, to achieve a duty cycle of approximately 50%, 17 chips are transmitted followed by a space equivalent to 15 chip periods Submission 12 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Packet Structure Submission 13

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Packet Structure Submission 13 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Spreading Codes (Length 16)

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Spreading Codes (Length 16) -1 -1 1 -1 -1 -1 1 1 -1 -1 1 1 -1 -1 -1 1 1 -1 -1 -1 1 -1 1 These code words (c) were found by exhaustive search based on the three following properties: – Low cyclic autocorrelation – Low cyclic cross-correlation between code words c – Low cross-correlation between code words (1, c) and (1, -c) Submission 14 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Throughput • The length

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Throughput • The length of the data PSDU (payload) is 32 octets. The data rate is 100 kbps (this is X 0 in this proposal) • Assumptions (refer to the figure on page 20 in the PHY selection criteria document) – – • a. Min. LIFSPeriod = 40 symbol periods a. Turnaround. Time = 12 symbol periods a. Unit. Backoff. Period = 20 symbol periods Length of ACK PSDU = 5 octets t_ack is the time between the end of the data frame and the beginning of the ACK frame – – Submission worst case, is t_ack = a. Turnaround. Time + a. Unit. Backoff. Period = 32 best case, t_ack is t_ack = a. Turnaround. Time = 12 15 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Receiver Architectures A. Differential

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Receiver Architectures A. Differential chip detection during both acquisition and data demodulation B. Differential chip detection during acquisition and non-coherent symbol detection during data demodulation Submission 16 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 More on Receiver Architectures

January 2005 doc. : IEEE 802. 15 -04/704 r 1 More on Receiver Architectures • In both architectues, acquisition is based on differential detection/combining – Does not require frequency offset correction and therefore leads to shorter preamble (=> less overhead) – Small performance loss at 20 ppm frequency error – If desired, frequency offset estimation can be carried out in parallel with synchronization • Architecture A Differential chip detection for data demodulation – Frequency offset correction may still be applied during PHR and PSDU to improve performance • Architecture B. Non-coherent symbol demodulation for data demodulation – Significant performance improvement, since we are now summing energy coherently across a whole codeword (which for data rates <= 100 kbps is 16 chips long) – Requires frequency offset estimation (during acquisition) and correction (during data demodulation) Submission 17 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Link Budget Submission 18

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Link Budget Submission 18 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Simulation Parameters •

January 2005 doc. : IEEE 802. 15 -04/704 r 1 System Simulation Parameters • • • • Frequency band: 4. 752 GHz (MB-OFDM band 4) 10 d. B bandwidth: 500 MHz Transmit power: -16. 1 d. Bm Transmit/Receive filter: 3 rd order Butterworth, corner frequency 180 k. Hz A/D converter: 528 MHz, 3 bits Noise figure: 7 d. B Data rate: 100 kbps PSDU size: 32 bytes PRF (chip rate): 3. 2 MHz Length of DS spreading code: 16 Length of preamble: 48 bits Length of SFD: 32 bits Length of PHR: 48 bits Modulation: DBPSK Demodulation method: differential detection No frequency offset Submission 19 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Spectrum TX Power: -16.

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Spectrum TX Power: -16. 1 d. Bm Submission 20 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 PER vs. Distance in

January 2005 doc. : IEEE 802. 15 -04/704 r 1 PER vs. Distance in AWGN (100 kbps) Submission 21 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 PER vs. Eb/No (100

January 2005 doc. : IEEE 802. 15 -04/704 r 1 PER vs. Eb/No (100 kbps) Submission 22 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 PER vs. Received Power

January 2005 doc. : IEEE 802. 15 -04/704 r 1 PER vs. Received Power (100 kbps) Submission 23 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Conclusions • UWB band

January 2005 doc. : IEEE 802. 15 -04/704 r 1 Conclusions • UWB band limited system • Meet all system requirements • Low signal repetition frequency to reduce ICI and need for high speed digital circuits (lower power consumption) • “Narrow” UWB bandwidth to reduce complexity • Remaining material will be presented at the next opportunity Submission 24 Roberto Aiello, Staccato Communications

January 2005 doc. : IEEE 802. 15 -04/704 r 1 802. 15. 4 a

January 2005 doc. : IEEE 802. 15 -04/704 r 1 802. 15. 4 a Early Merge Work Staccato Communications is actively collaborating with others Objectives: We encourage participation by any party who can help us reach our goals. • “Best” Technical Solution • ONE Solution • Excellent Business Terms • Fast Time To Market Submission 25 Roberto Aiello, Staccato Communications