July-2003 doc.: IEEE 802.15 - 03/123r6 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [The ParthusCeva Ultra Wideband.
Download ReportTranscript July-2003 doc.: IEEE 802.15 - 03/123r6 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [The ParthusCeva Ultra Wideband.
July-2003 doc.: IEEE 802.15 - 03/123r6 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [The ParthusCeva Ultra Wideband PHY proposal] Date Submitted: [05 May, 2003] Source: [Michael Mc Laughlin, Vincent Ashe] Company [ParthusCeva Inc.] Address [32-34 Harcourt Street, Dublin 2, Ireland.] Voice:[+353-1-402-5809], FAX: [-], E-Mail:[[email protected]] Re: [IEEE P802.15 Alternate PHY Call For Proposals. 17 Jan 2003] Abstract: [Proposal for a 802.15.3a PHY] Purpose: [To allow the Task Group to evaluate the PHY proposed] 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. PHY proposal Slide 1 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 The ParthusCeva PHY Proposal PHY proposal Slide 2 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Overview of Presentation • Coding – – – – DSSS Coding scheme - biorthogonal coding Ternary spreading codes Reed Solomon FEC code Optionally concatenated with convolutional code • Preamble • Implementation Overview • Performance – Link margin – Test results – Throughput, Multiple piconet performance • Complexity PHY proposal Slide 3 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Symbol coding • 64 biorthogonal signals [Proakis1] • 64 signals from 32 orthogonal sequences • Ternary sequences chosen for their auto-correlation properties • Code constructed from binary Golay-Hadamard sequences PHY proposal Slide 4 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Spreading code comparison Code Length mean aamf min aamf Best Ternary Golay Hadamard 40 5.90 4.54 Best Ternary Golay Hadamard 32 5.52 3.26 Best Binary Golay Hadamard 32 4.43 2.21 Best Binary Golay Hadamard 64 4.72 3.50 Orthogonal Gold 32 2.22 1.19 Orthogonal Gold 64 2.20 1.19 • Length 32 code chosen for aamf and best matching with bit rates. PHY proposal Slide 5 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Sample rate and pulse repetition frequency • Signal bandwidth chosen is 3.85GHz to 7.7GHz • Sampling rate chosen is 7.7Ghz • 32 chips per codeword, 6 channel bits / symbol PRF 55Mbps 110Mbps 220Mbps 490Mbps 980Mbps /880Mbps 0.48 Gpps 0.96 Gpps 1.92 Gpps 3.86Gpps 7.7Gpps 30 Msym/sec 8 60 Msym/sec 4 120 Msym/sec 2 240 Msym/sec 1 Symbol rate 15 Samples /pulse PHY proposal Msym/sec 16 Slide 6 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 FEC Scheme • Concatenated code for 110 , 220Mbps, 880Mbps – Reed Solomon outer code (235,255) – Convolutional rate 4/6 inner code • Reed Solomon code (43,63) for 490Mbps, 980Mbps PHY proposal Slide 7 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 FEC scheme - inner code • A 0.667 rate (rate 4/6) convolutional code was chosen for the inner code at 110 and 200 Mbps. [Proakis2] • Very low complexity 16 state code, constraint length 2, Octal generators 27, 75, 72. • Each of 16 states can transition to any other state, outputting 16 of 64 possible codewords. • Provides 3dB of gain over uncoded errors at a cost of 50% higher bit rate PHY proposal Slide 8 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Preamble Sequence PACn PACn …….. PACn PACn …….. PACn The preamble consists of 50-200 repetitions of PACn followed by 16 repetitions of its negative, PACn. The 180o transition to the negative provides a precise time marker for the receiver. PACn is a ternary sequence with perfect periodic autocorrelation i.e. its periodic autocorrelation is a Kronecker delta function. It is one of a family of ternary sequences with perfect periodic autocorrelation discovered by Valery Ipatov [Ipatov] and extended by Høholdt and Justesen [Høholdt et al]. There are many sequences in this family, e.g. lengths 381, 553, 651, 757, 781, 871, 993. Each piconet uses a different length sequence. This makes the cross correlation between preambles of different sequences very low. The preamble also serves as a marker for the packet. A receiver searches for a packet or a beacon by correlating with a copy of the particular PACn associated with that piconet. We propose using lengths 381,553,651,757,781 and 871. PHY proposal Slide 9 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 PAC properties • Because of the perfect autocorrelation property, the channel impulse response can be obtained in the receiver by correlating with the sequence and averaging the results. • Because the sequence consists of mostly 1, -1 with a small number of zeros, correlation can be economically implemented. (a length 553 PAC has 24 0’s) PHY proposal Slide 10 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Preamble properties • Very good detect rate and false alarm probability. Pfa and Pmd < 10-4 for CM1 to CM4 test suite at 10 metres. Detected in 2s using matched filter architecture. • Matched filter is equivalent of 553 parallel correlators • Different length sequences means other piconets won’t trigger detection i.e. Pfa still < 10-3 for a different piconets PACn, even at 0.3m separation. • Preamble length varies from ~5s to ~15s depending on the bit rate. Lower bit rates use longer preambles (Longer distances need more training time) PHY proposal Slide 11 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 PHY Header • The PHY header is sent at an uncoded 45Mbps rate, but with no convolutional coding. It is repeated 3 times. • The PHY header contents are the same as 802.15.3 i.e. Two octets with the Data rate, number of payload bits and scrambler seed. PHY proposal Slide 12 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Scrambler/Descrambler • It is proposed that the PHY uses the same scrambler and descrambler as used by IEEE 802.15.3 PHY proposal Slide 13 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Typical Tx/Rx configuration Antenna Single Chip Possible Output data at 55 - 960 Mbps Band Pass Filter* LNA Switch / Hybrid Fine/ Band Reject Filter Channel Matched filter (Rake Receiver) A/D 7.7GHz, 1 bit 8-240M symbols/sec 256 - 3800 Mchips/sec Band Pass Filter Band Reject Filter Chip to Pulse Generator Viterbi Decoder Correlator Bank Code Generator Convolutional encoder Descramble Input data at 55- 960 Mbps Scramble * Can be avoided with good LNA dynamic range PHY proposal Slide 14 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Possible RF front end configuration • Total Noise Figure = 6.6dB NF= 0.3dB (input referred) NF= 2.0dB NF= 3.5dB Fine Filter** BP Filter* LNA To Rx NF= 0.8dB Tx/Rx switch / hybrid Band reject Filter ** Filter From Tx * Can be avoided with good LNA dynamic range PHY proposal ** Depending on Local National or User requirements Slide 15 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Matched Filter configuration 4 Cn 1 Di Cn+N Di-N 4x 4x 4 Cn+1 4x Di-1 + ….. ….. 4x 4 4 bit adder Di-N-1 Cn+N+1 4x 4 4 1 4 ….. 4x 5 bit adder ….. + ….. PHY proposal Slide 16 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Matched Filter configuration • Structure repeated 16 times e.g. a 500 tap filter with 4 bit coefficients would have 500 x 16 x 4 AND gates in first stage • Calculates 16 outputs in parallel, each runs at (480/mps) MHz. – e.g. 120MHz for 220Mbps • Multiplier is 4 AND gates. • First adder stage is 4 OR gates. Very little performance loss. (0dB for CM1-3, 0.23dB for CM4). • Coefficients are pre-processed to remove smallest if two clash. • mps is max pulses/sample. = 1440/(channel bit rate (Mbps)) PHY proposal Slide 17 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Matched filter • 560 tap filter takes 135k gates or 0.82 sq mm in 0.13 standard cell CMOS • Worst case power consumption = 120mW ( at 490Mbps ), proportional to data rate. Much lower for CM1 because of fewer taps. • Matched filter re-used for correlation with training sequence during training phase • All simulations were carried out with this filter/correlator structure PHY proposal Slide 18 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Link Budget Parameter Value Value Value Value Throughput (Rb) 110 Mb/s 220 Mb/s 490 Mb/s 880 Mb/s Tx power ( PT ) -5.9dBm -5.9dBm -5.9dBm -5.9dBm Tx antenna gain ( GT ) 0 dBi 0 dBi 0 dBi 0 dBi Centre frequency 5.48GHz 5.48GHz 5.48GHz 5.48GHz Loss at 1 metre 47.1dB 47.1dB 47.1dB 47.1dB Loss at d metres 20 dB (10m) 12 dB (4m) 12 dB (4m) 6 dB (2m) Rx antenna gain 0 dBi 0 dBi 0 dBi 0 dBi Rx power -73dBm -65dBm -65dBm -62.5dBm Noise power/bit -93.6dBm -90.6dBm -87.2dBm -84.6dBm Rx Noise Figure 6.6dB 6.6dB 6.6dB 6.6dB Noise power/bit -86.6dBm -83.6dBm -80.6dBm -77.6dBm Min Eb/N01 (S) 2.3dB 2.3dB 3.0dB 2.3dB Imp. Loss2 (I) 4.0dB 4.0dB 4.0dB 4.0dB Link Margin 7.7dB 12.7dB 8.6dB 9.1dB -80.7dBm -77.7dBm -73.6dBm -71.7dBm Rx Sens. Level Notes: 1 - Minimum Eb/No for <8% PER for AWGN channel. 2 - 2 dB for 1 bit ADC and 2dB for timing jitter. Channel capture of <100% adds 0.5dB(CM1) to 2.5dB(CM4) PHY proposal Slide 19 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Distance achieved for mean packet error rate of best 90% = 8% 25 20 15 10 5 0 110M 220M 490M AWGN CM1 CM2 CM3 CM4 Mean PER = 8% AWGN CM1 CM2 CM3 CM4 110Mbps 23.4 m 16.7 m 15.0 m 15.0 m 15.0 m 220Mbps 16.6 m 11.5 m 10.3 m 10.7 m 10.6 m 490Mbps 10.1 m 6.5 m 5.6 m 5.5 m 5.0 m AWGN figures are for a fully impaired simulation except using a single ideal channel instead of CM1-4. PHY proposal Slide 20 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Distance achieved for at worst packet error rate of best 90% = 8% 25 20 15 10 5 0 110M 220M 490M AWGN CM1 CM2 CM3 CM4 Worst PER = 8% AWGN* CM1 CM2 CM3 CM4 110Mbps 23.4 m 14.2 m 12.5 m 14.1 m 13.5 m 220Mbps 16.6 m 9.7 m 8.8 m 9.6 m 9.6 m 490Mbps 10.1 m 5.4 m 4.8 m 4.9 m 3.9 AWGN figures are for a fully impaired simulation except using a single ideal channel instead of CM1-4. PHY proposal Slide 21 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 200 Mbps Performance comparison Worst PER = 8% AWGN CM1 CM2 CM3 PCVA - 220Mbps 16.6 m 9.7 m 8.8 m 9.6 m 9.6 m STM – 250Mbps 11.1 m 7.7 m 6.9 m - - OFDM – 200Mbps 14.1 m 6.9 m 6.3 m 6.8 m 5.0 m PHY proposal Slide 22 of 47 CM4 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 110 Mbps average PER Average PER vs Distance at 110Mbps 0 -0.5 -1 -2 log 10 PER -1.5 -2.5 -3 channel channel channel channel model model model model 18 19 1 2 3 4 -3.5 -4 10 PHY proposal 11 12 13 16 15 14 distance (m) Slide 23 of 47 17 20 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 220 Mbps average PER Average PER vs Distance at 220Mbps 0 -0.5 -1 -2 channel channel channel channel log 10 PER -1.5 -2.5 model model model model 1 2 3 4 -3 -3.5 -4 PHY proposal 8 8.5 9 9.5 11 10.5 10 distance (m) Slide 24 of 47 11.5 12 12.5 13 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 490 Mbps average PER Average PER vs Distance at 490Mbps 0 -0.5 -1 channel channel channel channel -2 log 10 PER -1.5 model model model model 1 2 3 4 -2.5 -3 -3.5 -4 PHY proposal 2 2.5 3 3.5 4 4.5 5 distance (m) Slide 25 of 47 5.5 6 6.5 7 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Multiple Piconet Interferers • Tests were done according to the Multiple Piconet interference procedure outlined in the latest revision of the selection criteria (03031r11). • The distance to the receiver under test was set at 0.707 of the 90% link success probability distance. • Tests results were obtained for 1,2 and 3 interfering piconets PHY proposal Slide 26 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Single adjacent piconet dint/dref 1 interferer 110Mbps CM1 CM2 CM3 CM4 0.40 0.39 0.38 0.38 220Mbps 0.55 0.54 0.56 0.55 490Mbps 1.33 1.34 1.33 1.31 Relative distance to a single adjacent piconet interferer PHY proposal Slide 27 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Two adjacent piconets dint/dref 2 interferers 110Mbps CM1 CM2 CM3 CM4 0.53 0.52 0.56 0.53 220Mbps 0.85 0.86 0.88 0.86 490Mbps 1.90 1.92 2.06 2.02 Relative distance to two adjacent piconet interferers PHY proposal Slide 28 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Three adjacent piconets dint/dref 3 interferers 110Mbps CM1 CM2 CM3 CM4 0.65 0.65 0.65 0.64 220Mbps 0.96 0.96 0.96 0.99 490Mbps 2.25 2.30 2.55 2.45 Relative distance to three adjacent piconet interferers PHY proposal Slide 29 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Co-channel interference • Different piconets use exactly the same data mode codes as each other. • Separation is achieved because – a) a different piconet will have a different impulse response and thus will not correlate with the matched filter which has been trained for the piconet of interest. – b) Codes won’t be synchronised • Co-channel data mode interference is exactly the same as adjacent channel interference. • Training to the preamble will be affected more markedly by co-channel interference. Difficult to simulate. PHY proposal Slide 30 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Co existence • Out of band signals, e.g. 802.11b, (< 3.1GHz and >10.6GHz) are always filtered out. • Any desired in band energy can be filtered out, with minimal effect on performance because the whole band is used to transfer data. • Only adverse effect is the transmit power reduction (e.g. Dropping 400MHz for 802.11a loses <0.5dB) PHY proposal Slide 31 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Co-existence with 802.11a • Filtering out the UNII band spectrum from the transmitter has very little effect on the performance • The receive matched filter will cope with it automatically • Only 1.25dB of power is lost by filtering out the Tx signal from 5GHz to6GHz • This is the equivalent of a 15% loss in distance PHY proposal Slide 32 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Interference and susceptibility • As for co existence, out of band signal, e.g. 802.11b, are always filtered out. • Again, any desired in band energy can be filtered out, with minimal effect on performance because the whole band is used to transfer data. • Only adverse effect is the receive power reduction (e.g. Dropping 400MHz for 802.11a loses <0.5dB), its just a part of the channel. PHY proposal Slide 33 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Narrowband interference • Immunity to narrowband interference • With no filtering – Processing a gain of e.g. ~24dBs at 110Mbps. Any interfering tone is reduced by this amount. • With digital notch filter – Tones can be detected at the A/D output. – A simple notch filter either at the input or output of the matched filter can then remove this completely with no loss in performance (if notch is narrow enough) PHY proposal Slide 34 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 PHY-SAP Data Throughput • At higher bit rates, a 1024 byte frame is very short. • The channel will be stationery for more than one frame so it is possible to send multiple frames for each preamble. • T_MIFS=1μs, T_SIFS=5μs, T_PHYHDR=1.1μs,T_HCS=0.29μs, T_MACHDR=1.45μs Payload Bitrate Preamble length T_PA_INIT, T_PA_CONT Throughput : 1 frame / Preamble Throughput : 4 frames / Preamble 110Mbps 15.5μs 88Mbps 104Mbps 220Mbps 8.3μs 167Mbps 205Mbps 480Mbps 4.7μs 324Mbps 435Mbps PHY proposal Slide 35 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Scalable solution • 55 - 980 Mbps. Gate count depends on maximum bit rate and power consumption of baseband PHY is proportional to bit rate. • 880Mbps has 90% link success on CM1-CM3 at over 3.4m, 2.8m and 2.6m with exactly same RF and sample rate as the other rates • Receiver here uses 3.85 - 7.7GHz. – 2.5dB extra performance gain if full band used. – 1.0dB lower performance if 3.2-4.8 GHz band used with ~50% power reduction PHY proposal Slide 36 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Complexity - Area/Gate count, Power consumption • Gate equiv Area (mm2) 2.8 Power mW Rx Data @ 120Mbps 80 Power mW Rx Data @ 480Mbps 80 Power mW Preamble Rx 80 RF section (Up to and incl. A/D - D/A) - RAM - 24kbits 22k 0.13 10 10 10 Matched filter 135k 0.41 25 100 - Channel estimation (length 871 PAC) 24k extra 0.15 - - 45 Viterbi Decoder, RS decoders Rest of Baseband Section 60k 0.36 5 20 - 65k 0.40 25 60 25 Total 306k 4.25mm2 145mW 270mW 160mW These figure are for a standard cell library implementation in 0.13µm CMOS PHY proposal Slide 37 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 How can it be so good? • Where does this large Performance/Cost/Power advantage come from • Compare with two proposals other proposals - TFI OFDM and Multiband • These two were chosen because of their prominence and fairly comprehensive results available PHY proposal Slide 38 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Performance- How much better? • All similar under AWGN, i.e. 20 odd metres at 110Mbps. • 200/220/240 Mbps – ~50% farther than either TFI-OFDM or Multiband over CM1 – 92% farther than TI-OFDM and 230% farther than Multiband over CM4 • 110/120 Mbps – 22/25% farther over CM1 – 22% farther than TFI-OFDM and 75% farther than Multiband over CM4 • 480 Mbps - 86% farther than TFI-OFDM over CM1, no CM4 or Multiband figures available. • NB: The distances quoted for TFI-OFDM and Multiband do not take into account the 4.7dB loss required for FCC compliance i.e. a further 1.72 gain factor. PHY proposal Slide 39 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Performance - Why is it better? • Gap is small with no multipath at low rates, larger as the multipath increases and speed increases. • Multiband approach only gathers a small amount of multipath energy. 16ns at 120Mbps and 8ns at 240Mbps. CM4 channels have significant energy spread over 100ns • ParthusCeva PHY - has equivalent of a 230 finger rake. • Ternary codes were chosen for their multipath immunity PHY proposal Slide 40 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Power • 110/120Mbps Rx @ 0.13 – This approach – Multiband approach – TFI - OFDM up to 145mW 170-200mW 205mW • Why so good? – Simple analog Rx section • Single bit ADC • No AGC • No mixer – No FFT in the receiver. Matched filter with 1 bit inputs. Low complexity decoders PHY proposal Slide 41 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Cost • Comparison at 0.13µ – This approach – Multiband approach – TFI - OFDM approach 4.25mm2 7.3mm2 6.9mm2 • Why the difference ? – Same reasons as power, low complexity digital and analog requirements PHY proposal Slide 42 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Summary of advantages • Ternary spreading codes – Better auto-correlation properties • Perfect PAC training sequence • Simple RF section – 1 bit A/D converter – No AGC required – No Rx mixers required • Long rake possible - near multipath immunity – 4 bit coefficients – 1 bit data – no multipliers • Cost and Power very similar to Bluetooth PHY proposal Slide 43 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 The ParthusCeva PHY PHY proposal Slide 44 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 The ParthusCeva PHY PHY proposal Slide 45 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 The ParthusCeva PHY PHY proposal Slide 46 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Backup Slides PHY proposal Slide 47 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Self evaluation : General Criteria CRITERIA Unit Manufacturing Complexity (UMC) Signal Robustness Interference And Susceptibility Coexistence REF. 3.1 IMPORTANCE LEVEL B PROPOSER RESPONSE + Single chip possible, small silicon area 3.2.2 A 3.2.3 A + Interferers filtered out + Tx filtering. Technical Feasibility Manufacturability 3.3.1 A + Single chip possible Time To Market 3.3.2 A + Technology proven Regulatory Impact Scalability (i.e. Payload Bit 3.3.3 A 3.4 A + Within FCC limits + 30 - 960Mbps possible. Very low complexity solution possible 3.5 C + Within 40cm with no extra effort Rate/Data Throughput, Channelization – physical or coded, Complexity, Range, Frequencies of Operation, Bandwidth of Operation, Power Consumption) Location Awareness PHY proposal Slide 48 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Self evaluation : PHY protocol CRITERIA Size And Form Factor REF. 5.1 IMPORTANCE LEVEL B PROPOSER RESPONSE + Single chip solution possible PHY-SAP Payload Bit Rate & Data Throughput Payload Bit Rate 5.2.1 A 5.2.2 A Simultaneously Operating Piconets Signal Acquisition 5.3 A 5.4 A + 480Mbps evaluated, 960Mbps possible + Very close to Payload rate 480Mbps gives 415Mbps + Different length training sequences + Pfa and Pmd <10-4 after 2s Link Budget 5.5 A + Overhead available Sensitivity 5.6 A + As for link budget Multi-Path Immunity 5.7 A Power Management Modes 5.8 B Power Consumption 5.9 A Antenna Practicality 5.10 B + Matched filter means multipath has very little effect + Most power used while receiving packets + Simple RF section, simple coding reduces power consumption + Easier because Highest frequency no more than twice the lowest. PHY-SAP Data Throughput PHY proposal Slide 49 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Self evaluation : MAC enhancements CRITERIA MAC Enhancements And Modifications PHY proposal REF. IMPORTANCE LEVEL 4.1. C Slide 50 of 47 PROPOSER RESPONSE + Externally similar to 802.15.3 PHY Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Ternary orthogonal sequences • From any base set of 32 orthogonal binary signals, can generate 32C16 sets of 32 orthogonal ternary sequences. • Generate by adding and subtracting any 16 pairs. • Generally, if the base set has good correlation properties, so will a generated set. PHY proposal Slide 51 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Good base binary set • Base set is a set of binary Golay-Hadamard sequences • Take a binary Golay complementary pair. • s116=[1 1 1 1 1 1 -1 -1 -1 1 1 -1 -1 1 -1 1]; • s216=[1 1 1 1 -1 -1 1 1 -1 1 1 -1 1 -1 1 -1]; • if A=circulant(s116) and B=circulant(s216) • • and G32= A B BT -AT then G32 is a Hadamard matrix. [Seberry] • This type has particularly good correlation properties[Seberry] • Detector can use the Fast Hadamard Transform PHY proposal Slide 52 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Creating Orthogonal Ternary Sequences • Take a matrix of binary orthogonal sequences • Add any two rows to get a ternary sequence • Sum of any other two rows is orthogonal to this • Continue till all the rows are used • Repeat but subtracting instead of adding PHY proposal Slide 53 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Orthogonal Ternary Example • E.g. 1 1 1 1 • 1 -1 1 -1 • 1 -1 -1 1 • 1 1 -1 -1 • pairing 1 with 3 and 2 with 4 gives this orthogonal matrix • • • • PHY proposal 2 2 0 0 0 0 2 -2 0 2 0 -2 2 0 2 0 Slide 54 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Finding good Ternary Golay Hadarmard codes • Large superset of orthogonal sequence sets to test • Define aperiodic autocorrelation merit factor (aamf) as the ratio of the peak power of the autocorrelation function to the mean power of the offpeak values divided by the length of the code. • Random walk used to find set with best aamf PHY proposal Slide 55 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Code comparison Code Length mean aamf min aamf Best Ternary Golay Hadamard 40 5.90 4.54 Best Ternary Golay Hadamard 32 5.52 3.26 Best Binary Golay Hadamard 32 4.43 2.21 Best Binary Golay Hadamard 64 4.72 3.50 Orthogonal Gold 32 2.22 1.19 Orthogonal Gold 64 2.20 1.19 • Length 32 code chosen for aamf and best matching with bit rates. PHY proposal Slide 56 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Rate 4/6 Convolutional coder + 3 bits out + Map every 6 bits to one of 64 biorthogonal codewords 1 of 64 + 2 bits in PHY proposal Slide 57 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Ternary Orthogonal Length 32 Code Set • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • + 0 0 0 0 0 0 0 0 + 0 0 + 0 0 + + 0 + + + + + 0 0 0 0 0 0 0 + 0 + 0 0 0 0 0 0 0 + + + 0 0 + + + + 0 + 0 - + 0 0 + 0 0 0 0 0 0 0 + 0 0 0 + 0 + 0 + + + + + 0 0 0 0 + 0 + 0 0 0 + 0 0 0 0 0 + 0 0 + + 0 + + + 0 + 0 PHY proposal 0 + 0 0 + 0 0 + 0 0 0 + 0 0 0 + 0 + 0 + 0 + + + 0 0 0 0 0 0 + 0 0 + + 0 0 + + 0 0 0 + + 0 + 0 0 + + 0 0 0 0 0 0 + + 0 0 0 + 0 0 0 0 + 0 + 0 0 0 + + 0 + + + 0 0 0 0 + 0 0 0 0 + + 0 0 + 0 + 0 0 + 0 + + 0 0 + + + + 0 0 0 + 0 0 0 0 0 0 0 0 0 + 0 0 0 + 0 + + + + + 0 + 0 0 0 0 + 0 0 0 0 0 + + 0 + 0 + 0 0 + 0 + + + 0 + + 0 0 0 0 0 + 0 0 0 0 0 0 0 + + 0 + 0 0 + 0 + + + 0 0 0 0 + 0 0 0 0 + 0 0 0 0 + + + + 0 0 + 0 + 0 + + - 0 + + 0 + 0 0 + 0 + 0 0 + 0 0 + 0 0 + 0 0 0 + 0 0 + 0 0 + 0 + 0 0 0 0 0 0 + 0 + 0 + 0 + + + 0 0 + 0 0 + + 0 0 + 0 0 0 0 + 0 + 0 0 + 0 + + + + 0 0 0 0 0 + 0 0 0 0 0 0 + + + 0 0 0 + + + 0 + + 0 0 0 0 + 0 0 + 0 + 0 0 + 0 0 0 + 0 0 + 0 0 0 0 + 0 0 0 0 0 + 0 0 + 0 0 0 + + 0 + + 0 0 + 0 0 0 0 0 0 0 0 - 0 0 0 0 + 0 0 0 + 0 0 + + + 0 0 0 0 + 0 0 0 0 0 0 0 + 0 0 0 + 0 + + 0 0 + 0 0 0 0 0 + 0 + 0 + 0 0 0 0 0 + 0 0 0 0 + 0 0 + 0 0 + 0 0 0 0 0 + 0 0 0 0 0 + + 0 0 + 0 + + 0 0 0 0 0 + 0 + 0 0 0 + 0 0 0 0 0 0 0 + + 0 0 0 0 0 + 0 0 + 0 + 0 + 0 0 + 0 0 0 0 + 0 0 + 0 0 0 0 0 0 + + + 0 + 0 0 + 0 + 0 0 0 0 0 0 0 0 0 0 0 + 0 0 + 0 + 0 0 0 0 0 + 0 0 0 + 0 0 + 0 0 0 0 0 0 0 0 0 + 0 0 0 0 + 0 + 0 0 + + 0 0 + - 0 0 0 0 0 0 0 + 0 0 0 0 0 + 0 + 0 0 + + 0 + + 0 + 0 0 0 0 + 0 0 0 0 0 0 0 + 0 0 + + 0 0 - 0 + 0 0 0 0 0 0 + 0 0 0 0 0 + 0 + 0 0 + + 0 - + 0 + + 0 + + 0 0 0 0 0 0 0 0 0 0 0 0 + 0 0 0 + 0 + + 0 + 0 + 0 0 0 0 0 0 0 0 0 0 0 0 + Slide 58 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 Matlab Code to generate PAC sequences • • • • • • % function phi=ipatov(nu,multiplier,mul2); % % Generate a length nu, ternary perfect periodic autocorrelation sequence % using Singer Cyclic Difference Sets e.g. (553, 24, 1) % function phi=ipatov(nu,multiplier,mul2); • if nargin==1 multiplier=1; mul2=-1; end • if nargin==2 mul2=-1; end • phi=0; • • • if gcd(nu,multiplier)>1; return; end % must not be a common divisor of nu • • • if gcd(nu,mul2)>1; return; end % must not be a common divisor of nu • switch nu • • • case 7 % nu=7;k=3;lamda=1; D=[1 2 4 ]; • • • case 13 nu=13;k=4;lamda=1; D=1+[ 0 1 3 9 ]; • • • case 21 nu=21;k=5;lamda=1; D=[3,6,7,12,14]; • • • case 31 nu=31;k=6;lamda=1; D=[1 5 11 24 25 27 ]; • • • case 57 nu=57;k=8;lamda=1; D=[0 1 6 15 22 26 • • • • • case 63 % multipliers 1,5 nu=63;k=31;lamda=15; D=1+[0 1 2 3 4 16 18 19 24 26 41 45 48 49 52 • case 73 PHY proposal % multipliers 1,-1 are most commonly good % multipliers 1,-1 are most commonly good 45 55 ]; gives perfect ternary 6 27 54 7 8 9 12 13 14 ... 28 32 33 35 36 38 ... 56 ]; Slide 59 of 47 Michael Mc Laughlin, ParthusCeva July-2003 doc.: IEEE 802.15 - 03/123r6 References • • • • • [Proakis1] John G. Proakis, Digital Communications 2nd edition. McGraw Hill. pp 224-225. [Proakis2] John G. Proakis, Digital Communications 2nd edition. McGraw Hill. pp 466-470. [Seberry et al] J. Seberry, B.J. Wysocki and T.A. Wysocki, Golay Sequences for DS CDMA Applications, University of Wollongong [Ipatov] V. P. Ipatov, “Ternary sequences with ideal autocorrelation properties” Radio Eng. Electron. Phys., vol. 24, pp. 75-79, Oct. 1979. [Høholdt et al] Tom Høholdt and Jørn Justesen, “Ternary sequences with Perfect Periodic Autocorrelation”, IEEE Transactions on information theory. PHY proposal Slide 60 of 47 Michael Mc Laughlin, ParthusCeva