1. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 1 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: Proposal for TG6 Clause 9 Comment Resolution Date Submitted: 13 July, 2010 Source: Anuj Batra, Texas Instruments and Mark Dawkins, Toumaz Technology Re: Response to IEEE 802.15.6 Letter Ballot comments Abstract:This document proposes several resolutions for Letter Ballot 55, specifically for the Narrowband PHY section. Purpose:For discussion by IEEE 802.15 TG6 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.

2. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 2 Header Check Sequence Comment(s): S9-1, S9-26 –“The order of transmission of HCS seems to be MSB to LSB and is not consistent with LSB to MSB transmission chosen for the rest of the document” Proposed Resolution: –Change MSB to HCS0 and LSB to HCS3 in Figure 109, or –Replace Figure 109 with the following Discussion: –Changing the labels on the shift registers will any eliminate confusion

3. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 3 Transmit Order (1) Comment(s): S9-2, S9-27 –“first bit of the message – first bit of the message to be transmitted?” Proposed Resolution: –Add text into line 17 of 9.4.1.2: “…m50 is the first bit of the message to be transmitted and m0 is the last bit …” Discussion: –This addition clarifies the meaning of m50, since by previous definition the first bit transmitted is always the least significant bit.

4. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 4 Transmit Order (2) Comment(s): S9-80, S9-92 –“first bit of the message – first bit of the message to be transmitted?” Proposed Resolution: –Replace 9.4 (b) step (1) with the following text: “Divided into blocks of messages starting with the LSB of the least significant octet of the PSDU and continuing to the MSB of the most significant octet of the PSDU” –Replace 9.4 (b) step (2) with the following text: “Shortening bits may then be appended to the messages, which are then encoded into codewords using a BCH (63, 51) encoder to achieve the desired code rate, according to 9.4.1.1 Discussion: –Above text addresses how the PSDU into broken into messages

5. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 5 Bit Interleaver Comment(s): S9-4, S9-29 –“The bit interleaver is used only for the spread case. This is ambiguous in the document” Proposed Resolution: –Add the following text to the start of line 9 in Section 9.4.4: “In the case that spreading factor is equal to 2 or 4, the output …” Discussion: –Adding this text clarifies that the bit interleaver is only used when the spreading factor is 2 or 4.

6. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 6 Reference Phase Comment(s): S9-6, S9-7, S9-31, S9-32, S9-57, S9-116 –“what is S(0)? Is this the first symbol to be transmitted of the PLCP preamble?” Proposed Resolution: –Replace line 11 in Section 9.4.6.2 with the following text: “where S(-1) = exp(j  /2) is the reference for the first symbol of the preamble and..” –Change the range in line 10 (equation 65) to start at k=0 Discussion: –These change remove any ambiguity for the reference phase

7. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 7 Constellation Mapping Comment(s): S9-8, S9-33 –“ what is the bit stream – is this the concatenated bit stream?” Proposed Resolution: –Bring Section 9.4.6 Constellation Mapping one level higher, thereby making it into its own section –Insert the following text under the title heading Constellation Mapping: “The constellation mapper operates on the binary bit stream b(n), which is the concatentation of the PLCP preamble, the PLCP header and the PSDU.” –Change the first sentence of Section 9.4.6.1 to the following: “For the GMSK constellation, b(n), n = 0, 1, …, N-1 shall be mapped onto …” –Change the first sentence of Section 9.4.6.2 to the following: “For the D-PSK constellations, b(n), n = 0, 1, …, N-1 shall be mapped onto …” Discussion: –These changes clarify the definition of the binary bit stream

8. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 8 Scrambler (1) Comment(s): S9-5, S9-30 –“The first bits coming out of the scrambler to scramble data after initialization is ambiguous” Proposed Resolution: –Add the following text to section 9.4.5 on line 9: “For example, when the Scrambler Seed is set to 0, the first 20 bits out of the scrambler are: 0 0 0 1 1 1 0 0 0 0 1 1 1 1 1 0 1 1 1 0.” Discussion: –Enumerating the first 20 bits of the scrambler for a given scrambler seed will eliminate any confusion

9. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 9 Scrambler (2) Comment(s): S9-18 –“No mention of how many bits are needed to flush the scrambler” Proposed Resolution: –Reject comment Discussion: –The narrowband PHY uses a side-stream scrambler, therefore the scrambler does not need to be flushed since the data bits are not fed into the scrambler

10. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 10 Sensitivity Comment(s): S9-12, S9-37, S9-48 –“The minimum sensitivity numbers can be lower than the numbers listed in Table 49.” Proposed Resolution: –Change text in line 19 Section 9.8.1 to “For a packet error rate (PER) of less than or equal to 10% with a PSDU of 255 octets in AWGN, a compliant device shall achieve receiver sensitivities listed in Table 49, or better” –Change heading for column 3 in Table 49 to “Maximum Input Level at Sensitivity (dBm) Discussion: –Clarifies that the sensitivity can be lower than the number listed in Table 49

11. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 11 ED Threshold (1) Comment(s): S9-13, S9-22, S9-38, S9-49, S9-65 –“ED Threshold should be defined as 10 dB above the minimum receiver sensitity, which corresponds to the lowest data rate” Suggestion: –Modify first bullet to say “10 dB above the minimum specified receiver sensitivity (see 9.8.1) OR” Counter-proposal Resolution: –Modify first bullet to say "10 dB above the receiver sensitivity as defined in Table 49 for the lowest data rate within a given band (see 9.8.1) OR" Discussion: –Counter-proposal eliminates any confusion over what is the minimum specified receiver sensitibity

12. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 12 ED Threshold (2) Comment(s): S9-43 –“Specifying details for "ED Threshold" is key to ensuring interoperabililty with existing MICS systems compliant with standards such as EN 301 839-1 V1.3.1.” Proposed Resolution: –Replace the text in the second bullet, section 9.8.4 with the following: “that which is prescribed by local regulatory requirements, or applicable standards, whichever is lower.” Discussion: –It is dangerous to reference any specific documents, because if the documents change, then the standard also needs to be unnecessarily updated

13. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 13 ED Threshold (3) Comment(s): S9-45 –“Specifying details for ‘ED Measurement Time’ is key to ensuring interoperabililty with existing MICS systems compliant with standards such as EN 301 839-1 V1.3.1.” Proposed Resolution: –Replace the text in the second bullet, section 9.8.5 with the following: “that which is prescribed by local regulatory requirements, or applicable standards, whichever is longer in duration.” Discussion: –It is dangerous to reference any specific documents, because if the documents change, then the standard also needs to be unnecessarily updated

14. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 14 pMIFS Comment(s): S9-63 –“The way this statement is written, it gives no tolerance to the transmitter or receiver requirements” Proposed Resolution: –Change the first sentence in Section 9.6.4 to the following: “For burst mode transmissions, the inter-frame spacing between uninterrupted successive transmissions by a device shall be between pMIFS and pMIFS + 5  s.” Discussion: –The text above adds a tolerance to the pMIFS value.

15. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 15 pCCATime Comment(s): S9-82, S9-94, S9-119, S9-138 –“change to pCCATime shall be the lower of those specified in Table 44 or by local regulatory authorities” –“text should read ‘whichever is lower’” Proposed Resolution: –In Section 9.6 line 13, change “which” to “whichever” Discussion: –Text already states that the pCCATime is the lower of values in Table 44 or the values specified by the local regulatory authorities

16. doc.: IEEE 802. 15-10-0556-02-0006 Submission July 2010 Anuj Batra and Mark Dawkins, TI and ToumazSlide 16 SRRC Equation Comment(s): S9-95 –“The standard does not define a Square Root Raised Cosine (SRRC) filter for the transmitter” Proposed Resolution: –Insert a new section 9.x, entitled “SRRC Pulse Shape”, to follow the section “Constellation Mapping” –Insert the following the text into this new section: “The square-root raised cosine (SRRC) pulse shape with roll-off factor  and symbol period T s described in Equation (x) shall be used to filter the symbols and shape the spectrum. (x) The exact value for the roll-off factor  and the duration of the SRRC pulse shape is implementation dependent.” –In Section 9.7.7 line 6, change “matched SRRC filtering” to “SRRC filtering matched to the transmitter under test” –In Tables 26-32, replace “Symbol Rate (ksps)” with “Symbol Rate = 1/T s (ksps)” Discussion: –This new section defines the time-domain impulse response for an SRRC pulse shape