IEEE P802.15

Wireless Personal Area Networks

Project	IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)
Title	IEEE 802.15.4z MAC
Date Submitted
Source	Peter Sauer (Microchip)
Re:	Updated Text for 802.15.4z_D006e
Abstract	This contribution proposes updated text for the baseline draft 802.15.4z_D006e
Purpose	Provision of the text to facilitate its incorporation into the draft text of the IEEE 802.15.4z standard currently under development in TG4z.
Notice	This document does not represent the agreed views of the IEEE 802.15 Working Group. It represents only the views of the participants listed in the “Source(s)” field above. 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
Patent Policy	The contributor is familiar with the IEEE-SA Patent Policy and Procedures: <http://standards.ieee.org/guides/bylaws/sect6-7.html#6> and <http://standards.ieee.org/guides/opman/sect6.html#6.3>. Further information is located at <http://standards.ieee.org/board/pat/pat-material.html> and <http://standards.ieee.org/board/pat>.

MAC functional description

Overview

[ir-0385: P4L20 add following text]

For the LRP-SRDEV the RMARKER position is illustrated in Figure 85.

[ir-0394: P5L4-7 remove text in line 4 to 7 and replace by]

The LRP-SRDEV supports secure authenticated ranging as described in 6.9.9. Provably secure ranging is guaranteed by distance bounding (distance commitment on payload). Informative and normative information for PHY implementation of distance bounding is provided in Annex G, including proofs, guarantees and literature references.

Ranging time units

[ir-0386: P5L13-14 change to]

For the LRP UWB PHY the time unit is 2-16 of the basic chipping rate of 1 MHz, which is approximately 15.26 ps.

Ranging procedures

Ranging procedure for SS-TWR with fixed reply time

[ir-0377, ir-0400: P15L18-24 replace text with]

The LRP-SRDEV also has the concept of fixed response time, or Return Time, (see 19.9), to remove the need for a data message to convey the reply time. This fixed return time is used in two-way round-trip time-of-flight ranging measurements without exchange of timestamps between the RDEV. An example of this is shown in Figure 8.

The ranging process uses Enh-Ack frames to achieve the fixed reply time defined by the phyFixedReplyTime attribute. During the configuration of the initiator and the responder the IE challenge and IE response are set for the header, data and reply time. The initiator device will start transmission with AR field and Ranging set, using the IE challenge and disabling retransmissions. The ranging counter starts with the transmission of the last symbol and the responder will reply to this reception after the fixed reply time. The response includes the IE response data in the Enh-Ack data. The reception of the challenge data is indicated to the higher layer of the responder. The reception of the Enh-Ack frame will stop the ranging counter at the RMARKER position and confirm the Enh-Ack reception to the higher layer. The initiator device uses a timeout for the reception of the Enh-Ack frame which should be at least 2 times the fixed reply time. The FCS checking at the initiator and responder has to be set such to ignore any failures to prevent the reject of the frame data.

[ir-0399: P15L25 update Figure 8 (included in Visio file Figure8.vsd)]

Time scheduled and multi-device ranging

6.9.8.1 Scheduled ranging and the ranging block structure

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See text from ir-0408

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For the LRP PHY this TU is an integer multiple the chipping rate, the value being one of 250 µs and 333µs, i.e. 250 and 333 times the chipping rate. The maximum tolerance on timing for Ranging Block related MAC activities shall be ± 20 ppm.

[ir-0409: P20L36 Add following text]

For secure ranging with LRP UWB PHY, the NH (No header) can be considered which indicates the case with the RFRAME without header (see section 19.4.7). The time structure of NH Secure Ranging Round shall be similar as shown in Figure 14 for HRP NHD ranging.

MAC frame formats

IEs

Nested IE

[new: add to table 7-16]

Name=”Challenge IE”, data=X, sub-clause 7.4.4.68

Name=”Response IE”, Enhanced Ack=X, sub-clause 7.4.4.69

Advanced Ranging Control IE

[ir-0375: P53L6 extend table 7]

Add two columns on the right “HRP support” and “LRP support” and set mark “X” for HRP in all rows and for LRP in rows “non-secure SS-TWR”, “non-secure DS-TWR”, “secure SS-TWR with payload”, “secure DS-TWR with payload”

[ir-0376: P53L6 extend table 7]

Add two row below with “SS-TWR without header” and “DS-TWR without header” and set mark “X” in new column “LRP support” for both rows

Challenge IE

[new]

The Challenge IE includes the header information and challenge data for the ranging procedure with fixed reply time in combination with an Enh-Ack frame from the responder.

Response IE

[new]

The Response IE includes the header information and response data for the ranging procedure with fixed reply time and is included in the Enh-Ack frame from the responder.