Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Pulse Waveforms Proposal] Date Submitted: [November 16, 2005] Source: [Huan-Bang Li(1), Kenichi Takizawa(1), Yuko Rikuta(1), Shinsuke Hara(1), Tetsushi Ikegami(1), Ryuji Kohno(1), Toshiaki Sakane(2), Kiyohito Tokuda(3)] Company [(1) National Institute of Information and Communications Technology (NICT), (2)Fujitsu Limited, (3)Oki Electric Industry Co., Ltd.] Contact: Huan-Bang Li. Voice:[+81 46 847 5104, E-Mail: lee@nict.go.jp] Abstract: [Pulse waveforms proposal for DS-UWB radios] Purpose: [Solution proposal for technical parameters 15.4a] Notice: This document has been prepared to assist the IEEE P802.15. 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 P802.15.

Pulse Waveforms Proposal Huan-Bang Li, Kenichi Takizawa, Yuko Rikuta, Shinsuke Hara, Tetsushi Ikegami, and Ryuji Kohno National Institute of Information and Communications Technology (NICT) Toshiaki Sakane Fujitsu Limited, Kiyohito Tokuda Oki Electric Industry Co. Ltd.

Current Status of Vancouver Meeting Works have been done Peak PRF and chip rate (494MHz & 2ns) Modulation and FEC (2PPM & RS+1/2 convolutional code) ALOHA as mandatory channel access mechanism Four preamble lengths (64, 256, 1024, 4096 – symbols) Four data rates (100k, 3.25M, 13M, 26M – bps) Above 6GHz band plan. Works are on the way Specification on pulse waveforms Optional channel access mechanism

What’s the Problem? In the agreement of baseline, we only decided to use ‘deterministic pulse’. However, when a pair of transceiver with different pulse waveforms talk each other, significant mismatch may happan if we don’t give a definition or specification. Although we have some proposals on pulse waveforms, no decision has been reached so far. Guidelines are needed to select pulse waveforms. Optional pulse waveforms on table include chirp, chaotic, …

Proposed Solutions Mandatory Define a mandatory pulse waveform group Option Chirp on UWB Continuous spectrum (CS) pulse

1. Proposal on mandatory pulse waveforms

‘Mandatory Waveform Group’ The proposal is to restrict the mandatory pulse waveforms by defining a ‘mandatory waveform group’. Pulse waveforms in this group must meet the following conditions Pulse width (Because of the peak PRF used, this parameter may greatly affect the non-coherent receiver’s performance. E.g., less than 2 ns? With 90%? of energy in it). Interoperability (Pulses in this group can detect each other without obvious performance loss, e.g., less than 3 dB? with root raised cosine and Gaussian pulses)

Simulation results on interoperability between Gaussian and RRC

Simulation System Block Diagram Transmitter Pulse shaping (RRC filter) FEC K=3 conv MOD 2PPM＋BPSK Pulse shaping (Gaussian filter) Receiver Pulse shaping (RRC filter) (Gaussian filter) DEMOD VITERBI

Simulation Results (coherent receiver) RRC RRC Gaussian Gaussian

Simulation Results (noncoherent receiver) b / N [ d B ] a v e r g P R - G 8 1 2 6 4 3 2PPM+BPSK PRF = 494MHz K=3 convolutional code dB 1.6 R: Root-raise cosine waveform (Roll-off factor =0.3) G: Gaussian waveform RRC RRC Gaussian Gaussian

What Waveforms Can Be In The Mandatory Group? To start with some popular pulse waveforms including Gaussian (including bell-shaped Gaussian) Root Raised Cosine (RRC) ? Any other pulse waveforms meet the pulse width and interoperability conditions can be added the mandatory group. To leave room for new and good pulse waveforms.

2 Two optional Pulse Waveforms proposal

Option 1 Chirp on UWB

Statements in the Baseline on Chirp Potential for optional chirp mode (at best where allowed). It is confirmed by the Japanese regulatory body (MIC) that chirp signaling UWB is compliant in Japan. Add chirp specifically for UWB as SOP mechanism This has been shown in our previous documents (04-0468-01) (04-0716-01) (05-0300-00)

Overall Block Diagram With Optional CS Transmitter BW = 494 MHz FEC Spreading Pulse shaping GA modulation CHIRP D Local oscillator Receiver Pre-Select Filter LPF GA 1 to 2-bit ADC De-spreading Decision/ FEC decoder LNA LPF GA 1 to 2-bit ADC DE- CHIRP I Local oscillator Sync. Q Additional circuits to DS-UWB as an option

Simulation Block Diagram for SOP

Simulation results for SOP DS with chirp DS-only

Main Advantages for Chirp Additional dimension to support SOP Chirp slopes and chirp patterns Better performance than DS codes Combination with FDM and/or CDM Additional link margins Low peak-to-average ratio. Robustness against interference and multipath Excellent correlation characteristics Potential high precision ranging.

Option 2 Continuous spectrum pulse (05-0544-00)

CS Pulse Examples Gaussian without CS 1ns/1GHz CS 5ns/1GHz CS

Mismatch Detection (CS Receiver) Inverse CS-Filter -10ns delay/GHz cos sin | | Transmitter Gaussian (0ns delay) +10ns delay/GHz LPF Output DSCS CSCS

Mismatch Detection (DS Receiver) Transmitter Gaussian (0ns delay) +10ns delay/GHz -10ns delay/GHz cos sin | | LPF Output CSDS

Block Diagram For SOP Simulation (Case of Receiver with Optional CS) Delay: 10ns/GHz Delay: -10ns/GHz DS-UWB Transmitter CS filter Receiver Filter -1 Delay: 10ns/GHz Delay: -10ns/GHz DS-UWB Transmitter 2-SOP CS filter Receiver Filter -1

Block Diagram For SOP Simulation (Case of DS-only Receiver) Delay: 10ns/GHz DS-UWB Transmitter CS filter 2-SOP Receiver Delay: -10ns/GHz

Enhanced SOP With CS Filtering S = DS, I = DS S = DS w/t CS, I = DS w/t CS DS+CS 1 transmitter DS+CS 2 transmitter S DS+CS 3 transmitter I I DS+CS 1 receiver 4dB 4dB

Enhanced SOP With CS Filtering S = DS, I = DS S = DS w/t CS, I = DS DS+CS 1 transmitter DS 2 transmitter S DS 1 transmitter I I DS+CS 1 receiver 3dB 3dB

Advantages of CS Filtering (Compared to DS-only Devices) To support SOP, CS filtering provides additional anti-interference ability. In comparison with DS-only piconets, Piconets with different CS filtering can reduce the interference against each other (additionally larger SIR). (CS CS) Piconet with CS filtering can reduce the interference from DS-only piconets (additionally larger SIR). (DS  CS) DS-only piconet receivers smaller interference from piconets with CS filtering (additionally larger SIR). (CS  DS)

Realization Examples Frequency (MHz) Insertion loss (dB) +2ns/GHz -5 -10 -15 Insertion loss (dB) +2ns/GHz +1ns/GHz -1ns/GHz -2ns/GHz 5 4 3 2 1 Group delay (ns) 　3200　　3380　　3560　 3740　　3920　　4100　 4280　　4460　　 4640 　 4820　 　5000 Frequency (MHz)

Conclusion Remarks ‘Mandatory pulse group’ proposal Specifications for mandatory pulse waveforms. Optional chirp on UWB proposal Additional dimensions to support SOP Optional continuous spectrum pulse proposal SOP performance enhancement