March 2003 doc IEEE 802 15 03125 r

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Project: IEEE P 802. 15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Philips TG 3 a CFP Presentation] Date Submitted: [02 March, 2003] Source: [Charles Razzell, Dagnachew Birru, Bill Redman-White, Stuart Kerry] Company [Philips] Address [1109 Mc. Kay Drive, San Jose, CA 95131, California, USA] Voice: [(408) 474 -7243], FAX: [(408) 474 -5343], E-Mail: [charles. razzell@philips. com] Re: [IEEE P 802. 15 -02/372 r 8 “IEEE P 802. 15 Alternate PHY Call For Proposals” dated 17 January, 2003] Abstract: [This presentation gives an overview of the Philips proposal for an alternative physical layer for IEEE P 802. 15. 3 a based on a multi-band UWB approach. ] Purpose: [Philips requests that the task group considers the merits of the following physical layer proposal and evaluates the content in conjunction with other responses to the 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(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 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Philips TG 3 a CFP Presentation An alternate high-rate PHY for Wireless Personal Area Networks Submission 2 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Outline of Presentation • • • Summary of Proposal Review of Spectral Keying™ Modulation Example choice of parameters to obtain required data rates Advantages of low pulse repetition rate FEC approach Pico-net isolation techniques Transmitter power control Receiver Implementation Issues Parallel/Serial dimensioning of receiver structure Scalability for low cost Conclusions Submission 3 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Summary of Proposal • Scalable data rates to 480 Mbps and beyond • Spectral Keying. TM modulation* • Compliant with FCC 02 -48, UWB Report & Order • Multiband system, scalable from 4 -10 bands, occupying 2 - 6 GHz bandwidth • Supports 4 co-located piconets *Modulation scheme originally proposed by General Atomics who own this trademark Submission 4 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Multi-Band Modulation (1) pulsed OFDM f 6 f 5 f 4 Information capacity proportional to number of sub -carriers. f 3 f 2 f 1 Submission Peak/mean ratio too high 5 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Multi-band Modulation (2) staggered pulses with fixed order f 6 f 5 Fixed order: information capacity proportional to number of sub -carriers f 4 f 3 f 2 f 1 Submission Peak/mean ratio is much reduced! 6 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Spectral Keying™ (1) Introduce Sequence Keying Use sequence as information bearing parameter. Information capacity is proportional to # subcarriers + log 2(n!) Submission 7 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Spectral Keying™ (2) Sequence Keying in addition to PSK 45 Sequence QPSK Total 40 Use of sequence bits approx. doubles number of bits per pulse of QPSK system when 8 subcarriers are used. 35 30 # of bits 25 20 15 10 5 0 1 2 3 4 5 6 7 8 9 10 # of frequencies Submission 8 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Coding gain of Spectral Keying™ (n=5) Spectral Keying vs. BPSK 0 10 SK(n=5) BPSK -2 10 -4 BER 10 -6 10 -8 10 -10 10 -12 10 0 1 2 3 4 5 6 7 8 9 10 Eb/No [d. B] Submission 9 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Summary of Spectral Keying™ • Use of sequence to carry information significantly increases information per pulse • This allows the interval between successive pulses to be increased. • This “extra” guard time can be used for ISI reduction and/or possible insertion of timeinterleaved piconets • The modulation remains robust, even with ~4 bits per symbol on each frequency band. Submission 10 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Example Parameters for Required PHY Data Rates Parameter Value Required PHY Data Rate 110 Mbps 200 Mbps 480 Mbps Symbol Rate 11 MHz 22 MHz Number of used bands 6 6 8 Coding Rate, R 0. 5 0. 75 No. used sequence bits 8 8 14 No. of used phase bits 12 12 16 Delivered data rate 110 Mbps 220 Mbps 495 Mbps Submission 11 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Example Parameters Continued Parameter Value Required PHY data rate 110 Mbps 200 Mbps 480 Mbps Number of bands 6 6 8 3 ns 3 ns Pulse duration 18 ns 24 ns Pulse Repeat Interval 91 ns 40. 5 ns 72. 9 ns 27. 5 ns 21. 5 ns Sub-pulse duration Guard Time Submission 12 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Advantages of low pulse repetition rate Impulse response realizations (CM 2) 1 Next impulse response starts here (11 MHz) 0. 5 0 Next impulse response starts here (22 MHz) -0. 5 -1 -1. 5 0 20 40 60 80 100 120 Time (n. S) Submission 13 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Advantages of Low Pulse Repetition Rate High ISI zone CM 2 represents NLOS 0 -4 m CM 3 represents NLOS 4 -10 m Next impulse response starts here (11 MHz) Next impulse response starts here (22 MHz) How much spreading gain would be required to achieve similar ISI reduction? Submission 14 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Forward Error Correction Approach • • • (based on results from IMEC’s T@MPO core) Parallel Concatenated Convolutional Turbo Codes 8 -state Recursive Systematic Convolutional Codes Collision-free interleaving patterns[1] Parallel SISO units process sub-frames Early stop criterion minimizes energy usage Decoding latency of 5 ms per block [1] A. Gulietti et al. “Parallel Turbo Code Interleavers; Avoiding collisions in access to storage elements. ” Electronics Letters vol. 38 No 5. Submission 15 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Channelization for Pico-nets • Propose to use a combination of frequency interleaving and time interleaving Ch 1 3. 4 GHz 4. 2 GHz 5. 0 GHz 5. 8 GHz 6. 6 GHz 7. 4 GHz Submission Ch 2 3. 8 GHz 4. 6 GHz 5. 4 GHz 6. 2 GHz 7. 0 GHz 7. 8 GHz } 2 16 Time division into even and odd time slots Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Concept for Time Division of Pulse Interval Power decay profile from 2 interleaved pico-nets (CM 2) Net 1 0 Net 2 average power (d. B) -5 Two 110 Mbps piconets are time interleaved with 11 MHz pulse rate each. -10 -15 -20 -25 0 10 20 30 40 50 delay (ns) 60 70 80 90 Passive scanning (probe) Submission 17 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Evaluation of Candidate Sub-pulse Slots by Measuring Preamble Quality Phase bits=1 Submission Phase bits=0 18 Preamble may be designed to allow MUI to be estimated in all four quadrants of a pulse interval. The “best” slot is chosen for transmission of the immediately following frame. Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Closed loop power control • An additional use of the pre-amble quality feedback mechanism is to allow for closed power control • Preamble acknowledgement word could include 2 power control and 2 sub-slot selection bits. • Closed loop power control is considered essential for dense deployment scenarios (e. g. multiple laptops in a conference room) • Additional quality information can be gathered during the data-bearing part of the packet to assist with power control and sub-slot selection. Submission 19 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Rx - High Performance Implementation Quadrature LOs may be low-spec on-chip oscillators with low area and power. LOs Shared with Tx Path Common front-end; can reduce power with SK duty cycle Submission 3 -4 bits ADC helped by AGC per band 20 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Rx - Low Power/Cost Implementation Common front-end; can reduce power with SK duty cycle ADC +Rake Rx replaced by analog detector with AGC Saving of ~60 m. W power from ADCs + Rake Rx Submission 21 Presented by C. Razzell and S. Kerry - Philips

March 2003 Submission Tx Implementation 22 doc. : IEEE 802. 15 -03/125 r 0 Low spec LO shared with RX channels Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Consideration of Serial vs. Parallel Receiver Structures • Since the sequence of frequencies is unknown and can’t be anticipated, parallel frequency-selective branches are needed • However, most of the duplicated circuits are very small on chip (oscillators, mixers). • Receiver branches may need to sample a significant time window – to allow for different propagation delays in different sub-bands under non-LOS condititions – to allow for collection of multipath echoes for RAKE combining Submission 23 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Consideration of Serial vs. Parallel Receiver Structures (cont. ) • Entirely serial reception of the sequence of tones is likely to cause performance loss in multipath conditions due to sparse sampling of the energy in each sub-band. • Entirely parallel energy collection in the different sub-bands need not be the only alternative • Partial serialization of the Spectral Keying modulation can be used to realize an excellent compromise… Submission 24 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Partial Serialization of Spectral Keying 3 ns f 6 f 5 f 4 f 3 f 2 f 1 18 ns Submission 18 ns 25 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Partial Serialization of Spectral Keying f 3 f 2 f 1 18 ns f 6 f 5 f 3 f 2 f 4 f 1 6 ns 18 ns 6 ns • No information loss w. r. t. fully parallel Spectral Keying • Same ML decoding algorithm can be applied • The number of receiver branches can be halved • Further degrees of serialization can be considered Submission 26 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Net-2 f 6 f 5 f 4 f 3 f 2 f 1 Net-1 Partial Serialization is Compatible with Time-division of Pico-nets f 3 f 2 f 1 f 6 f 5 f 4 18 ns Submission 18 ns 27 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Comments on Scalability • RAKE combining need not be used. • Low cost receiver implementation possible using analog correlator with single-bit sampling. • Full serialization may be used when the number of sub-bands is low and the pulse repetition interval is sufficiently long (for low cost and low data rate applications). Submission 28 Presented by C. Razzell and S. Kerry - Philips

March 2003 doc. : IEEE 802. 15 -03/125 r 0 Conclusions 1. 2. 3. 4. 5. 6. 7. 8. Spectral Keying™ provides a high order modulation scheme with inherent robustness (coding gain w. r. t. BPSK). The increased number of bits per pulse allows us to use a low pulse repetition rate which reduces ISI. In addition to lower ISI, we obtain energy conservation related to Spectral Keying™low duty cycle. Pico-net isolation can be achieved in the frequency and time dimensions (2 channels in each dimension). Transmitter power control is strongly recommended to enable dense deployment scenarios Different degrees of parallel/serial tradeoff can be implemented to divide the number of receiver branches by 2 or more. Maintaining some degree of parallelism leads to more optimum reception in multipath conditions. Can use high performance digital receiver, or low cost/power version. Submission 29 Presented by C. Razzell and S. Kerry - Philips