Submission Title: [SFD comparison] Date Submitted: [18−July−2006] Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [SFD comparison] Date Submitted: [18−July−2006] Source: [Michael Mc Laughlin] Company [Decawave Ltd.] Address [25 Meadowfield, Sandyford, Dublin 18, Ireland] Voice:[+353−1−2954937 ], FAX: [What’s a FAX?], E−Mail: [michael@decawave.com] Re: [802.15.4a.] Abstract: [Compares properties of three SFDs which have been proposed] Purpose: [To promote discussion in 802.15.4a.] 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. Mc Laughlin, Decawave
The three sequences are: July 2006 Three SFDs which have been proposed are compared by looking at the correlator outputs. The three sequences are: V = −0−+0−00 −0−+0−00 0+0+00−+ +000+−00 +00+−0+0 +00+000+ 0++−−−0− +000++00 Y = +−000−0+ 0−−0+000 0−+00−00 +−−−−0−0 +00++000 0+0+−0+0 +000−++0 −+−−−000 Z = 0+0−+00− 0+0−+00− −00+0−0+ 0+000−0− 0−00+0−− 0−+0000+ +00−−−+− ++0000++ where a + sign indicates a positive preamble sequence, a − sign indicates a negative preamble sequence and a 0 indicates 31 (or 127) zeros. Mc Laughlin, Decawave
Sequence V correlator output using Length 31 code 3 as inner code July 2006 Sequence V correlator output using Length 31 code 3 as inner code Mc Laughlin, Decawave
Sequence Y correlator output using Length 31 code 3 as inner code July 2006 Sequence Y correlator output using Length 31 code 3 as inner code Mc Laughlin, Decawave
Sequence V correlator output using Length 31 code 2 as inner code July 2006 Sequence V correlator output using Length 31 code 2 as inner code Mc Laughlin, Decawave
Sequence Y correlator output using Length 31 code 2 as inner code July 2006 Sequence Y correlator output using Length 31 code 2 as inner code Mc Laughlin, Decawave
Lots of −2 outputs before the main output July 2006 Sequence V correlator output using Length 31 code 2 as inner code Lots of −2 outputs before the main output Mc Laughlin, Decawave
This is the only one −2 before the main output July 2006 Sequence Y correlator output using Length 31 code 2 as inner code This is the only one −2 before the main output Mc Laughlin, Decawave
Sequence Z correlator output using Length 31 code 2 as inner code July 2006 Sequence Z correlator output using Length 31 code 2 as inner code Mc Laughlin, Decawave
+1/−1 is worst peak before the main output July 2006 Sequence Z correlator output using Length 31 code 2 as inner code +1/−1 is worst peak before the main output Mc Laughlin, Decawave
Sequence Z correlator output using Length 31 code 2 as inner code July 2006 Sequence Z correlator output using Length 31 code 2 as inner code Mc Laughlin, Decawave
Sequence Z correlator output using Length 31 code 2 as inner code July 2006 Sequence Z correlator output using Length 31 code 2 as inner code Mc Laughlin, Decawave
July 2006 Non – coherent The non coherent results for the three codes were compared also, and show quite similar results Mc Laughlin, Decawave
Summary All three will work very well for the long detector July 2006 Summary All three will work very well for the long detector Sequences V & Z have the advantage of two outputs for the short detector Sequences Y & Z have zero output during preamble for coherent cases Sequence Z has worst case +/-1 before the +4 for the short detector Mc Laughlin, Decawave
July 2006 Conclusion Sequence Z has all the best qualities and none of the downsides and would make the best SFD. Mc Laughlin, Decawave