ETSI TS 103 325 V1.2.1 (2022-07)

Smart Body Area Network (SmartBAN); Low Complexity Medium Access Control (MAC) for SmartBAN

RTS/SmartBAN-005r1

General Information

• Status: Not Published
• Technical Committee: SmartBAN - Smart Body Area Network
• Current Stage: 12 - Completion
• Due Date: 09-Aug-2022
• Completion Date: 20-Jul-2022

Standards Content (Sample)

TECHNICAL SPECIFICATION
Smart Body Area Network (SmartBAN);
Low Complexity Medium Access Control (MAC)
for SmartBAN
2 ETSI TS 103 325 V1.2.1 (2022-07)

Reference
RTS/SmartBAN-005r1
Keywords
health, interface, interoperability, protocol
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ETSI
3 ETSI TS 103 325 V1.2.1 (2022-07)
Contents
Intellectual Property Rights . 6
Foreword . 6
Modal verbs terminology . 6
1 Scope . 7
2 References . 7
2.1 Normative references . 7
2.2 Informative references . 7
3 Definition of terms, symbols and abbreviations . 8
3.1 Terms . 8
3.2 Symbols . 9
3.3 Abbreviations . 9
4 Introduction and Background . 10
5 General MAC Framework . 11
5.0 Different device types . 11
5.1 Frequency Spectrum . 12
5.2 Channel Format . 12
5.2.1 Control Channel (CCH) Format . 12
5.2.2 Data Channel (DCH) Format . 12
5.2.2.0 Data channel description . 12
5.2.2.1 Scheduled Access Slot Structure . 13
5.2.2.2 Control and Management Slot Structure . 14
5.2.2.3 Multi-use Access Slot Structure . 14
5.3 User Priorities . 15
5.4 Node IDs . 15
5.5 Information Units . 15
6 Frame Formats . 16
6.1 MAC General Frame Format. 16
6.1.0 General description . 16
6.1.1 MAC Header . 16
6.1.1.0 MAC Header Format. 16
6.1.1.1 Frame Control . 17
6.1.1.1.0 Frame Control Format . 17
6.1.1.1.1 Protocol Version . 17
6.1.1.1.2 Acknowledgement (ACK) Policy . 17
6.1.1.1.3 Frame Type . 17
6.1.1.1.4 Frame Subtype . 18
6.1.1.1.5 Sequence Number . 18
6.1.1.1.6 Fragment Number . 18
6.1.1.1.7 Non-final Fragment . 18
6.1.1.1.8 Command Acknowledgement . 18
6.1.1.2 Recipient ID . 18
6.1.1.3 Sender ID . 19
6.1.1.4 BAN ID . 19
6.1.1.5 FCS . 19
6.1.2 MAC Frame Body . 19
6.1.3 Frame Parity. 19
6.2 Management Frames . 19
6.2.1 Control Channel Beacon (C-Beacon) . 19
6.2.1.0 Control Channel Beacon Frame Format . 19
6.2.1.1 Hub Address . 20
6.2.1.2 Slot Length . 20
6.2.1.3 Time Slots . 21
6.2.1.4 Interference Mitigation . 21
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4 ETSI TS 103 325 V1.2.1 (2022-07)
6.2.1.5 Duty Cycling . 21
6.2.1.6 DCH Channel Number . 21
6.2.1.7 Initial State . 21
6.2.1.8 Time Stamp . 21
6.2.1.9 PHY Version . 21
6.2.1.10 Number of Nodes . 21
6.2.1.11 Destination Channel . 22
6.2.2 Data Channel Beacon (D-Beacon) . 22
6.2.2.0 Data Channel Beacon Frame Format . 22
6.2.2.1 Hub Address . 22
6.2.2.2 Inter-Beacon Interval . 23
6.2.2.3 Control and Management Period Start Slot . 23
6.2.2.4 Inactive Period Start Slot . 23
6.2.2.5 Function Indicator . 23
6.2.2.5.0 Function Indicator field . 23
6.2.2.5.1 Downlink Data Indicator . 23
6.2.2.5.2 Slot Reassignment Indicator . 23
6.2.2.5.3 Channel Migration Indicator . 23
6.2.2.6 Multi-use Access . 23
6.2.2.7 Time Stamp . 23
6.2.2.8 Downlink/Slot Reassignment (D/SR) List . 24
6.2.2.9 Slot Reassignment Timing . 24
6.2.2.10 Channel Migration Information . 24
6.2.2.10.1 Migration Timing . 24
6.2.2.10.2 Channel Number . 24
6.2.3 Connection Request (C-Req) . 24
6.2.3.0 Connection Request Frame Format . 24
6.2.3.1 Recipient Address . 25
6.2.3.2 Sender Address . 25
6.2.3.3 Enhanced Supplement . 25
6.2.3.4 PHY Capability . 25
6.2.3.5 PHY Version . 26
6.2.3.6 Requested Wakeup Phase . 26
6.2.3.7 Requested Wakeup Period . 26
6.2.3.8 Uplink Allocation Request . 26
6.2.3.9 Downlink Allocation Request . 27
6.2.4 Connection Assignment (C-Ass) . 27
6.2.4.0 Connection Assignment Frame Format . 27
6.2.4.1 Recipient Address . 27
6.2.4.2 Node ID . 27
6.2.4.3 Assigned Wakeup Phase . 28
6.2.4.4 Assigned Wakeup Period . 28
6.2.4.5 Assigned Supplement . 28
6.2.4.6 Assigned PHY Capability . 28
6.2.4.7 Uplink Assignment . 29
6.2.4.8 Downlink Assignment . 29
6.2.5 Slot Reassignment (S-Ras) . 29
6.2.6 Disconnection Request (D-Req) . 29
6.2.6.0 Disconnection Request command . 29
6.2.6.1 Length . 30
6.2.6.2 Recipient ID . 30
6.2.7 Disconnection Response (D-Res) . 30
6.3 Control Frames (C-Frame) . 30
6.3.1 Acknowledgement/Negative Acknowledge Frame (ACK/NACK) . 30
6.4 Data Frames (D-Frame) . 30
7 MAC Functions . 30
7.1 General . 30
7.2 SmartBAN Creation and Connection Initialization . 30
7.2.1 SmartBAN Creation . 30
7.2.2 Connection Initialization . 31
7.3 Channel Access . 32
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5 ETSI TS 103 325 V1.2.1 (2022-07)
7.3.1 Scheduled Channel Access . 32
7.3.1.0 Scheduled Channel Access . 32
7.3.1.1 Starting Scheduled Access . 32
7.3.1.2 Using Scheduled Access . 32
7.3.1.3 Modifying Scheduled Access . 32
7.3.1.4 Ending Scheduled Access . 32
7.3.2 Slotted Aloha Channel Access . 33
7.3.2.0 Description . 33
7.3.2.1 Starting Slotted Aloha Channel Access. 33
7.3.2.2 Using Slotted Aloha Channel Access . 33
7.3.2.3 Ending Slotted Aloha Channel Access . 33
7.3.3 Multi-use Channel Access . 33
7.3.3.0 Description . 33
7.3.3.1 Starting Multi-use Channel Access . 34
7.3.3.1.0 Description . 34
7.3.3.1.1 Backoff Algorithm . 34
7.3.3.1.2 Re-use Channel Access (RCA) . 34
7.3.3.1.3 Priority Channel Access (PCA) . 34
7.3.3.2 Using Multi-use Channel Access . 35
7.3.3.2.0 Description . 35
7.3.3.2.1 Scheduled Access Period . 35
7.3.3.2.2 Control and Management Period . 35
7.3.3.3 Ending Multi-use Channel Access . 35
7.4 Supplementary Downlink Data Transmission . 35
7.5 Slot Re-assignment . 36
7.6 Data Channel Migration . 37
8 MAC Parameters . 38
Annex A (normative): Multi-use Channel Access . 39
History . 40

ETSI
6 ETSI TS 103 325 V1.2.1 (2022-07)
Intellectual Property Rights
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ETSI in respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the
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Foreword
This Technical Specification (TS) has been produced by ETSI Technical Committee Smart Body Area Network
(SmartBAN).
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI
7 ETSI TS 103 325 V1.2.1 (2022-07)
1 Scope
The present document specifies low complexity Medium Access Control (MAC) for SmartBAN.
The present document applies to short range, wireless communication between wearable sensors devices and the hub
coordinator. The present document specifies MAC protocol designed to facilitate spectrum sharing with other devices.
The present document describes:
• Channel Structure.
• MAC Frame Formats.
• MAC functions.
The devices are capable of operating in all or any part of the frequency band shown in Table 1.
Table 1: Industrial, Scientific and Medical (ISM) frequency band
Direction of Transmission Industrial, Scientific and Medical (ISM) frequency band
Transmit / Receive 2,4 GHz to 2,4835 GHz

2 References
2.1 Normative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are necessary for the application of the present document.
[1] ETSI TS 103 326 (V1.2.1): "Smart Body Area Network (SmartBan); Enhanced Ultra-Low Power
Physical Layer".
2.2 Informative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] ETSI EN 300 328-1 (V1.3.1): "Electromagnetic compatibility and Radio spectrum Matters (ERM);
Wideband Transmission systems; Data transmission equipment operating in the 2,4 GHz ISM
band and using spread spectrum modulation techniques; Part 1: Technical characteristics and test
conditions".
ETSI
8 ETSI TS 103 325 V1.2.1 (2022-07)
[i.2] IEEE™ Std. 802.15.6-2012: "IEEE Standard for Local and metropolitan area networks - Part 15.6:
Wireless Body Area Networks".
[i.3] IEEE™ Std. 802.15.4-2011: "IEEE Standard for Local and metropolitan area networks - Part 15:4:
Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specification for Low-Rate
Wireless Personal Area Networks".
[i.4] ETSI TS 103 805: "Smart Body Area Network (SmartBAN); Relay Functionality for SmartBAN
Medium Access Control (MAC)".
[i.5] ETSI TS 103 806: "Smart Body Area Network (SmartBAN); Hub to Hub Communication for
SmartBAN Medium Access Control (MAC)".
3 Definition of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the following terms apply:
active period: period within the superframe period that is ready for frame reception and transmission
active state: internal power management state that is ready for the frame reception and transmission
allocation: one or more time intervals that a node or a hub obtains using an access method for initiating one or more
frame transactions
beacon: frame transmitted by a hub to facilitate network management, such as the coordination of medium access and
power management of the nodes in the SmartBAN, and to facilitate clock synchronization therein
beacon period: duration when a beacon is transmitted
connection: relation between a node and a hub in a Body Area Network (BAN), substantiated by an identification
assigned to the node by the hub and by access arrangement between them
device: entity conforming to the SmartBAN medium access control and physical interface to the wireless medium
downlink: communication link for transfer of management and data traffic from a hub to a node
frame: uninterrupted sequence of octets delivered by the Medium Access Control (MAC) sublayer to the Physical
(PHY) layer, or vice versa, within a node or a hub
hub: entity that possesses a node's functionality and coordinates the medium access and power management of the
nodes in the SmartBAN
hub to hub mode: optional enhanced operation mode where hubs of neighbouring SmartBANs may form a connection,
obtain allocation(s), and transmit and receive management and data traffic between them
inactive period: period in time following an active transmission sequence during which the equipment does not
transmit or receive
medical device: any instrument, apparatus, appliance, software, material or other article, whether used alone or in
combination, together with any accessories, including the software intended by its manufacturer to be used specifically
for diagnostic and/or therapeutic purposes and necessary for its proper application, intended by the manufacturer to be
used for human beings for the purpose of:
• diagnosis, prevention, monitoring, treatment or alleviation of disease;
• diagnosis, monitoring, treatment, alleviation of or compensation for an injury or handicap;
• investigation, replacement or modification of the anatomy or of a physiological process;
ETSI
9 ETSI TS 103 325 V1.2.1 (2022-07)
• control of conception,
and which does not achieve its principal intended action in or on the human body by pharmacological, immunological
or metabolic means, but which may be assisted in its function by such means
multi-use channel access mode: mode of operation where the slot structure during the scheduled and control and
management periods is accessible by multiple different priorities based on a temporal order
node: entity conforming to the SmartBAN medium access control and physical interface to the wireless medium
operating frequency: frequency at which the equipment can be operated
priority channel access: highest priority access during multi-use channel access
relay mode: optional enhanced operation mode where a node entity is temporarily assigned by the hub the functionality
to relay frames received from another node to the hub and vice versa
re-use channel access: lowest priority access during multi-use channel access enables re-use of scheduled but not
utilized slots
scheduled access: one or more scheduled reoccurring time intervals that a node and a hub obtains using scheduled
access for initiating frame transactions
NOTE: A scheduled allocation is an uplink or downlink allocation suitable for servicing high or low duty cycle
periodic or quasi-periodic traffic on a committed schedule.
star network: logical network partition comprising a hub and zero or more nodes whose medium access and power
management are coordinated by the hub
uplink: communication link for transfer of management and data traffic from a node to a hub
3.2 Symbols
For the purposes of the present document, the following symbols apply:
× Mathematical multiplication of the term immediately preceding the symbol and the term
immediately following the symbol
CP Maximum Contention Probability
max
CP Minimum Contention Probability
min
GHz Gigahertz
L Number of time slots in Inter-Beacon Interval
D
L Length of MAC Frame Body (bits)
F
L Slot length variable utilized in calculating the duration of a time slot
SLOT
MHz Megahertz
N Number of time slots in Control and Management Period
CM
N Number of time slots in Schedule Period
S
T Interval between control channel beacons
C
T Inter-Beacon Interval
D
T Duration of Inter-Frame Spacing
IFS
T Total duration of sensing period in Multi-use Channel Access
MUA
T Duration of a time slot
S
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
ACK ACKnowledgement
BAN Body Area Network
BC Backoff Counter
BCH Bose-Chaudhuri-Hocquenghem (code)
BE Backoff Exponent
C-Ass Connection Assignment
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10 ETSI TS 103 325 V1.2.1 (2022-07)
C-Beacon Control Channel Beacon
CCH Control Channel
C-Frame Control Frame
CP Contention Probability
CRC Cyclic Redundancy Check
C-Req Connection Request
D/SR Downlink/Slot Reassignment
D-Beacon Data Channel Beacon
DCH Data Channel
D-Frame Data Frame
D-Req Disconnection Request
D-Res Disconnection Response
EUI-48™ Extended Unique Identifier-48 bits
FCS Frame Check Sequence
FEC Forward Error Correction
IFS Inter-Frame Spacing
IM Information Module
ISM Industrial, Scientific and Medical
IU Information Units
MAC Medium Access Control
MCA Multi-use Channel Access
MPDU MAC Protocol Data Unit
NACK Negative Acknowledgement
NID Node ID
PBC Priority Backoff BE Counter
PCA Priority Channel Access
PHY Physical Layer
PRT Priority Re-Transmission
RBC Re-use Backoff Counter
RCA Re-use Channel Access
REP Repetition Coding
RT Re-Transmission
Rx Receive
SACA Slotted Aloha Channel Access
S-Ras Slot Reassignment
Tx Transmit
UP User Priority
4 Introduction and Background
Modern medical and health monitoring equipment are moving towards the trend of wireless connectivity between the
data collection or control centre and the medical devices or sensors. Therefore, a standardized communication interface
and protocol between the actors are required. This network of actors performing some medical monitoring or functions
is called a Smart Body Area Network (SmartBAN).
A SmartBAN is a simple, low complexity, low energy communication network that allows wireless connectivity
between the devices and a hub. The distinct features of the SmartBAN are ease of access, minimal listening, reliable
data transfer, provision of additional control messages (in the form of C-Beacons) for the low duty cycling nodes while
maintaining a simple and flexible protocol. SmartBAN also provides a multi-use channel access mechanism for
emergency and other high priority access and improved channel utilization.
The distinct characteristics of the SmartBAN are:
i) asymmetrical relation between the hub and the device, where the hub performs most scheduling and
computations;
ii) minimized listening period for the node;
iii) additional provisioning of beaconing messages and thus reliable and enhanced connectivity.
ETSI
11 ETSI TS 103 325 V1.2.1 (2022-07)
Additional information can be found from the following documents:
• ETSI EN 300 328-1 [i.1] defines requirements for equipment operating in the 2,4 GHz ISM band;
• IEEE™ Std. 802.15.6-2012 [i.2] defines an alternative standard for Wireless Body Area Networks; and
• IEEE™ Std. 802.15.4-2011 [i.3] defines a standard for Wireless Personal Area Networks.
5 General MAC Framework
5.0 Different device types
This clause provides the basic MAC framework for the nodes and hubs.
Two different device types can participate in SmartBAN: medical sensor device (node) and coordinator device (hub).
A hub is a device that acts as a SmartBAN coordinator. A node is any device that acts as an information source or an
information sink. One hub and at least one node constitute a SmartBAN.
A SmartBAN shall be organized into a star topology consisting of at least one node communicating directly with the
hub.
Figure 1: SmartBAN Topology
The hub and nodes shall communicate using communication media known as channels. A SmartBAN shall use two
different channel entities to enable communication between the hub and nodes. The channel entities are assigned the
following names:
• Data Channel (DCH)
• Control Channel (CCH)
Each SmartBAN shall utilize one Control Channel (CCH) and one Data Channel (DCH) at any one time.
The general MAC framework defined in the present document is extended with optional enhanced operation modes
defined in the following ETSI deliverables:
• ETSI TS 103 805 [i.4] defines relay functionality; and
• ETSI TS 103 806 [i.5] defines hub to hub communication for SmartBAN.
ETSI
12 ETSI TS 103 325 V1.2.1 (2022-07)
5.1 Frequency Spectrum
The frequency of operation shall fall within 2 401 MHz to 2 481 MHz. The channels shall be arranged in blocks of
2 MHz with centre frequencies:
f = 2 402 + 2×n MHz, where n = 0 to 39.
c
The channels are categorized into data and control channels with:
• 3 Control channels, where control frames (in the form of Control Channel Beacon) from the hub is transmitted;
• 37 Data channels, where data, control, and management frames are transmitted.
The channels list can be found in ETSI TS 103 326 [1].
5.2 Channel Format
5.2.1 Control Channel (CCH) Format
Only hub devices shall transmit on control channels. A hub shall select one control channel from the list of control
channels in ETSI TS 103 326 [1], Table 1 and transmit one Control Channel Beacon frame (C-Beacon) on the chosen
Control Channel (CCH) every T seconds. The format of the C-Beacon is set out in clause 6.1.
C
TC
Figure 2: Control Channel
5.2.2 Data Channel (DCH) Format
5.2.2.0 Data channel description
Both hub and node devices may transmit on the data channels. A hub shall select one data channel from the list of data
channels in ETSI TS 103 326 [1], Table 1 on which both hub and node devices in the associated SmartBAN may
transmit. For any SmartBAN, the data channel is partitioned into time intervals of T seconds, known as the Inter-
D
Beacon Interval. The boundaries of each Inter-Beacon Interval shall be marked by the transmission of a Data Channel
Beacon (D-Beacon). A hub shall transmit a D-Beacon at the beginning of each Inter-Beacon Interval.
Each Inter-Beacon Interval shall be partitioned into L distinct time epochs known as slots. The duration of each time
D
slot is T . The duration of each Inter-Beacon Interval shall be L × T seconds. Any device transmitting in a time slot
S D S
shall ensure that the transmission takes place within the duration of that time slot.
Each Inter-Beacon Interval shall consist of four distinct periods:
• Beacon Period, consisting of one single time slot, where the hub shall transmit the D-Beacon frame. No nodes
shall transmit in this period.
• Scheduled Period, consisting of N time slots, where scheduled transmissions and acknowledgements occur.
S
• Control and Management Period, consisting of N time slots, where unscheduled access and management and
CM
control signalling occur.
• Inactive Period, where no transmission occurs.
ETSI
C-Beacon
C-Beacon
13 ETSI TS 103 325 V1.2.1 (2022-07)
The time slots shall be identified by a 10 bit sequence denoting the position of the time slot in an Inter-Beacon Interval.
The Beacon Period, consisting of 1 time slot, shall have the sequence number 0000000000. Subsequent time slots shall
have sequence numbers incremented by the number of time slots following the Beacon Period.
Control and
Management Period
Scheduled Access Period (N * T ) (N * T )
S S CM S Inactive Period
…
…
…
T
S
Inter-Beacon Interval (T )
D
Figure 3: Access Periods in Data Channel
The Scheduled Access Period shall begin on the slot boundary immediately following the Beacon. The Scheduled
Access Period may be of zero length, in which case, the Control and Management Period shall begin immediately
following the Beacon Period. The Control and Management Period shall begin on the slot boundary immediately
following the Scheduled Access Period. The Inactive Period shall begin on the slot boundary immediately following the
Control and Management Period.
Three type
...