1. July 2017
Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [Suitability Evaluation of MAC Schemes]
Date Submitted: [9 July, 2017]
Source: [Joerg ROBERT] Company [Friedrich-Alexander University Erlangen-Nuernberg]
Address [Am Wolfsmantel 33, Erlangen, Germany]
Voice:[ ], FAX: [ ],
Re: []
Abstract: [This document presents the suitability evaluation for different MAC schemes that may be used for LPWAN.]
Purpose: [Presentation within IG LPWA]
Notice: This document has been prepared to assist the IEEE P 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 P
Joerg ROBERT, FAU Erlangen-Nuernberg

2. Suitability Evaluation of MAC Schemes
July 2017
Suitability Evaluation of MAC Schemes
Joerg Robert, FAU Erlangen-Nuernberg
Joerg Robert, FAU Erlangen-Nuernberg

3. doc.: IEEE 802.15-<doc#>
<month year>
doc.: IEEE <doc#>
July 2017
ALOHA ( I / II )
Device immediately starts transmission when it has data to transmit, it does not do listen before talk (LBT)
Performance can be improved is used in addition to diversity techniques (e.g. DSSS, FHSS)
Pros
Very simple
No coordination required
Cons
High probability of collisions, especially in case of long data
LBT may be required by frequency regulation
<author>, <company>

4. ALOHA ( II / II ) Interference Model Dense Medium Low None
July 2017
ALOHA ( II / II )
Interference Model
Dense
Medium
Low
None
Frequency Regulation
ETSI
FCC
ETSI/FCC
None
Data Length
<= 16 bytes
<= 64 bytes
<= 256 bytes
> 256 bytes
Data Period
Occasionally, less than 1/day
Occasionally 1/day
Occasionally 1/hour
Occasionally, more than 1/hour
Periodically 1/day
Periodically 1/hour
Periodically, more than 1/hour
July 2017
Active Interfering Users
Very High
High
Medium
Low
Communication Mode
Uplink
Downlink/Uplink
Uplink / Broadcast Downlink
Power Supply
CR 2025
2xAA
Energy Harvesting
External
Joerg Robert, FAU Erlangen-Nuernberg

5. doc.: IEEE 802.15-<doc#>
<month year>
doc.: IEEE <doc#>
July 2017
Slotted ALOHA ( I / II )
When the device has data to transmit it starts the transmission in the next slot
Pros
Improved performance wrt. ALOHA
Cons
High probability of collisions, especially in case of long data
Synchronization of the network required  additional power consumption
<author>, <company>

6. Slotted ALOHA ( II / II ) Interference Model Dense Medium Low None
July 2017
Slotted ALOHA ( II / II )
Interference Model
Dense
Medium
Low
None
Frequency Regulation
ETSI
FCC
ETSI/FCC
None
Data Length
<= 16 bytes
<= 64 bytes
<= 256 bytes
> 256 bytes
Data Period
Occasionally, less than 1/day
Occasionally 1/day
Occasionally 1/hour
Occasionally, more than 1/hour
Periodically 1/day
Periodically 1/hour
Periodically, more than 1/hour
July 2017
Active Interfering Users
Very High
High
Medium
Low
Communication Mode
Uplink
Downlink/Uplink
Uplink / Broadcast Downlink
Power Supply
CR 2025
2xAA
Energy Harvesting
External
Joerg Robert, FAU Erlangen-Nuernberg

7. doc.: IEEE 802.15-<doc#>
<month year>
doc.: IEEE <doc#>
July 2017
CSMA ( I / II )
Device senses whether the channel is used to avoid collisions, it only transmits if it senses the channel as free
Pros
Improved performance wrt. (Slotted) ALOHA
Required by regulation (e.g. ETSI)
Cons
Performance in LPWAN limited due to hidden node problem
Requires receiver in node
<author>, <company>

8. CSMA ( II / II ) Interference Model Dense Medium Low None
July 2017
CSMA ( II / II )
Interference Model
Dense
Medium
Low
None
Frequency Regulation
ETSI
FCC
ETSI/FCC
None
Data Length
<= 16 bytes
<= 64 bytes
<= 256 bytes
> 256 bytes
Data Period
Occasionally, less than 1/day
Occasionally 1/day
Occasionally 1/hour
Occasionally, more than 1/hour
Periodically 1/day
Periodically 1/hour
Periodically, more than 1/hour
July 2017
Active Interfering Users
Very High
High
Medium
Low
Communication Mode
Uplink
Downlink/Uplink
Uplink / Broadcast Downlink
Power Supply
CR 2025
2xAA
Energy Harvesting
External
Add: unpredictable latency
Joerg Robert, FAU Erlangen-Nuernberg

9. Fully Synchronized Network ( I / II )
<month year>
doc.: IEEE <doc#>
July 2017
Fully Synchronized Network ( I / II )
Base-station fully synchronizes controls the network, e.g. by using a super-frame structure with beacons
Pros
Collision can be controlled by the network
Cons
High synchronization overhead
Traffic of base-station may get in conflict with frequency regulations
Devices have to listen for beacons  increased energy consumption
Unclear behavior is base-station is interfered by other users
Potentially complex configuration
<author>, <company>

10. Fully Synchronized Network ( II / II )
July 2017
Fully Synchronized Network ( II / II )
Interference Model
Dense
Medium
Low
None
Frequency Regulation
ETSI
FCC
ETSI/FCC
None
Data Length
<= 16 bytes
<= 64 bytes
<= 256 bytes
> 256 bytes
Data Period
Occasionally, less than 1/day
Occasionally 1/day
Occasionally 1/hour
Occasionally, more than 1/hour
Periodically 1/day
Periodically 1/hour
Periodically, more than 1/hour
July 2017
Active Interfering Users
Very High
High
Medium
Low
Communication Mode
Uplink
Downlink/Uplink
Uplink / Broadcast Downlink
Power Supply
CR 2025
2xAA
Energy Harvesting
External
Joerg Robert, FAU Erlangen-Nuernberg

11. Any Questions or Comments?
July 2017
Any Questions or Comments?
Joerg Robert, FAU Erlangen-Nuernberg