Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Wisair-CFP-Response] Date Submitted: [4 January, 2005] Source: [Gadi Shor, Sorin Goldenberg] Company: [Wisair] Address: [24 Raoul Wallenberg st. Ramat Hachayal, Tel-Aviv, ISRAEL] Voice: [+972-3-7676605] FAX: [+972-3-6477608], E-Mail: [gadi.shor@wisair.com] Re: [802.15.4a CFP] Abstract: [802.15.4a CFP response] Purpose: [Response to WPAN-802.15.4a CFP] 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. Gadi Shor, Sorin Goldenberg (Wisair)

2. Proposal:UWB Low Rate Alternate Physical Layer for TG 802.15.4a Gadi Shor, Sorin Goldenberg (Wisair)

3. Proposal Contents • General Overview • Proposal Principles • Coding & Interleaving • Preamble • Band Management • Implementation • Performance • Evaluation Matrix Gadi Shor, Sorin Goldenberg (Wisair)

4. General Overview Gadi Shor, Sorin Goldenberg (Wisair)

5. UWB Low Rate • Task Group 4a have issued a call for proposal (CFP) for an alternate Physical layer for: • Low data rate communication • Ranging and location • This proposal is a response to the CFP • The proposal uses the UWB spectrum • The proposal supports low data rate communication, ranging and location Gadi Shor, Sorin Goldenberg (Wisair)

6. Proposal Overview • Available spectrum divided into fourteen, 528 MHz sub-bands • Similar to MB-OFDM division for co-existence • Multiple piconet isolation obtained through frequency division multiplexing (FDM) and symbol definition • 14 available bands and ability to share the same band • User separation using time domain multiple access techniques • Concatenated coding and repetition coding • Dynamic band management for interference and fading conditions mitigation • Scalable transmitter and receiver architecture • Ranging and location can be done using receiver capabilities Gadi Shor, Sorin Goldenberg (Wisair)

7. Proposal Principles Gadi Shor, Sorin Goldenberg (Wisair)

8. Band Plan Gadi Shor, Sorin Goldenberg (Wisair)

9. Transmitter Block Diagram Remark: Repetition can be distributed prior/post the differential encoder (under study) Gadi Shor, Sorin Goldenberg (Wisair)

10. Symbol definition • Symbol is based on shaped hierarchical sequences: • 16x8 samples hierarchical sequences • 48 samples zero padding suffix • 528 Mcps/176 samples = 3 Msps • Both shaped (flat PSD) and unshaped (constant envelope) allowed • For lower data rates symbols can be sent at a lower duty cycle (can replace transmit power control and save power consumption) • The coded data (after differential encoding and repetition) is modulated using BPSK • Each symbol is multiplied by an element from a PN sequence • Each symbol (after multiplication) is modulated using BPSK Remark: The modulation method can be replaced by orthogonal encoding (under study) Gadi Shor, Sorin Goldenberg (Wisair)

11. Coding & Interleaving Gadi Shor, Sorin Goldenberg (Wisair)

12. Error Correction Coding • Concatenated coding with differential encoding and repetition encoding • Allows simple decoding using sub-optimal decoders (e.g. using systematic or reversible encoders) • Coded data is spread over frequency and time for diversity • Exact scheme under study (ideas welcome) Gadi Shor, Sorin Goldenberg (Wisair)

13. Interleaving Scheme • The interleaving scheme is based on simple block/convolution interleaving Gadi Shor, Sorin Goldenberg (Wisair)

14. Scrambler • Use same scrambling scheme as MB-OFDM proposal: Gadi Shor, Sorin Goldenberg (Wisair)

15. Data Rates • Raw aggregate data rate is 3 Mbps • Information aggregate rate determined by • Coding rate • Repetition and Duty cycle • Many possible rates to select from • High aggregate rate allows many low rate users • Each user can have its own coding and spreading rates Gadi Shor, Sorin Goldenberg (Wisair)

16. Data Rates (2) Remark: Repetition and Duty Cycle factor is the effective rate NxR after including the symbol duty cycle (i.e. 1 out of N) and the repetition code rate (i.e. 1/R) Gadi Shor, Sorin Goldenberg (Wisair)

17. Preamble Gadi Shor, Sorin Goldenberg (Wisair)

18. Preamble Structure • Preamble is based on shaped hierarchical sequences • Preamble uses a cover sequence and frame synchronization sequence • Preamble contains channel estimation symbols for improved reception • Three different preamble lengths supported • Preamble includes symbols for antenna diversity Gadi Shor, Sorin Goldenberg (Wisair)

19. Band Management Gadi Shor, Sorin Goldenberg (Wisair)

20. FDM (14 bands) • Multiple access • Flexibility for world wide regulation • Simple co-existence with existing and future radios • Interference mitigation • Severe fading mitigation Gadi Shor, Sorin Goldenberg (Wisair)

21. Ranging and Location Gadi Shor, Sorin Goldenberg (Wisair)

22. Ranging and location • Modulation/demodulation scheme allows high resolution estimation of first path (and if needed complete channel) • Used as the basis for the ranging procedure • Can use special frame for improved ranging • Information can be distributed through the communication system to allow location, based on multiple relative ranging operations • See document for relative range estimation algorithm Gadi Shor, Sorin Goldenberg (Wisair)

23. Implementation Gadi Shor, Sorin Goldenberg (Wisair)

24. Transmitter • Many possible architectures (constant envelope or constant PSD, with/without DAC) • No need for I/Q modulator (BPSK) • Can use digital (+/-1), DAC based or analog sequences • Can be implemented using CMOS process • Low power consumption / Small die size / Share MB-OFDM radio Gadi Shor, Sorin Goldenberg (Wisair)

25. Receiver • Many possible architectures • Support for coherent and non-coherent receivers • Tradeoff between complexity and performance • Support analog and digital demodulation • Correlation/de-spreading can be done in analog or digital domains • ADC can work in bit rate, sample rate (or sample rate/8) • Support for architecture with no ADC Gadi Shor, Sorin Goldenberg (Wisair)

26. Performance Gadi Shor, Sorin Goldenberg (Wisair)

27. Performance • Scalable performance • Performance can be enhanced by receiver complexity • Performance under study Gadi Shor, Sorin Goldenberg (Wisair)

28. Summary • Proposed UWB system architecture provides spectrum flexibility for • World-wide regulation • Co-existence with current and future systems • Interference mitigation • Enables low complexity, low power , low cost solution • Good performance in multi-path and with multiple access interference • Enables simple implementation • Scalable receiver/transmitter for complexity & power tradeoffs Gadi Shor, Sorin Goldenberg (Wisair)

29. Backup Slides Gadi Shor, Sorin Goldenberg (Wisair)

30. Evaluation Matrix Gadi Shor, Sorin Goldenberg (Wisair)

31. Self Evaluation – General Solution Criteria Gadi Shor, Sorin Goldenberg (Wisair)

32. Self Evaluation – PHY Protocol Criteria Gadi Shor, Sorin Goldenberg (Wisair)