The document outlines a proposal for a work item aimed at supporting long-range cell operations for public safety, termed LCOPS. It emphasizes the importance of such technology in providing extensive coverage in difficult terrain and in disaster response scenarios, allowing for effective communication in the absence of traditional infrastructure. Key objectives include specifications for supporting receive-only user equipment and facilitating group communication with minimized joining times.

1. 3GPP TSG-SA WG1 #66 S1-141396
Sapporo, Japan, 12-16 May 2014 (revision of S1-141013)
Title: WID proposal: Long Range Cell Operation for Public Safety (LCOPS)
Source: III, ITRI
Contact: Yi-Hsueh Tsai (lucas@iii.org.tw), Hsuan-Li Lin, Terng-Yin Hsu, Jian-Ya Chu
Shubhranshu (shubhranshu@itri.org.tw), Zheng Yan-Xiu (zhengyanxiu@itri.org.tw )
Abstract: A new WID proposing normative work for supporting long range cell operation.
3GPP™ Work Item Description
For guidance, see 3GPP Working Procedures, article 39; and 3GPP TR 21.900.
Title * : Long Range Cell Operation for Public Safety
Acronym * : LCOPS
Unique identifier *
1 3GPP Work Area *
X Radio Access
X Core Network
X Services
2 Classification of WI and linked work items
2.0 Primary classification *
This work item is a … *
Study Item (go to 2.1)
X Feature (go to 2.2)
Building Block (go to 2.3)
Work Task (go to 2.4)
2.1 Study Item
Related Work Item(s) (if any]
Unique ID Title Nature of relationship
Go to §3.

2. 2.2 Feature
Related Study Item or Feature (if any) *
Unique ID Title Nature of relationship
530044 Study on Proximity-based Services
(FS_ProSe)
TR 22.803 Complementing Study
580059 Proximity-based Services (ProSe) Complementing Feature
Stage 1 in TS 22.115, TS 22.278;
560020 Group Communication System Enablers for
LTE (GCSE_LTE)
Complimentary Feature
Stage 1 in TS 22.468;
Go to §3.
2.3 Building Block
Parent Feature (or Study Item)
Unique ID Title TS
This work item is … *
X Stage 1 (go to 2.3.1)
Stage 2 (go to 2.3.2)
Stage 3 (go to 2.3.3)
Test spec (go to 2.3.4)
Other (go to 2.3.5)
2.3.1 Stage 1
Source of external requirements (if any) *
Organization Document Remarks
Go to §3.
2.3.2 Stage 2 *
Corresponding stage 1 work item
Unique ID Title TS
Other source of stage 1 information
TS or
CR(s)
Clause Remarks
If no identified source of stage 1 information, justify: *
Go to §3.
2.3.3 Stage 3 *
Corresponding stage 2 work item (if any)
Unique ID Title TS

3. Else, corresponding stage 1 work item
Unique ID Title TS
Other justification
TS or CR(s)
Or external document
Clause Remarks
If no identified source of stage 2 information, justify: *
Go to §3.
2.3.4 Test spec *
Related Work Item(s)
Unique ID Title TS
Go to §3.
2.3.5 Other *
Related Work Item(s)
Unique ID Title Nature of relationship TS / TR
Go to §3.
2.4 Work task *
Parent Building Block
Unique ID Title TS
3 Justification *
A long range cell is required to provide much larger coverage (up to 100km [1]). For larger area, a base station deployed in
high attitude such as high tower and with higher power transmission can provide larger coverage [2]. In addition, receivers
deployed in the fringe areas can enhance the range. Possible usage scenarios of long range cells are given as following:
A. Wireless access solution in areas where infrastructure is difficult to achieve: In areas such as mountain areas, jungles,
deserts, or islands, long range cell can provide broadband wireless access solution with good coverage under reasonable
cost.
B. Disaster first responder: In major disaster, the ground based communication infrastructure may suffer a severe
destruction. In such cases, long range cell could be quickly deployed to temporarily replace the ground communication
infrastructure and fast recover the wireless networks to enable critical information access such as the communication for
rescue mission, or emergency services.
When long range cells was adopted, the phenomenon that UE can only receive down-link signaling will become significant
and need to be addressed For example, the receive-only UE could obtained UE-to-Network Relay candidates from long
range cell instead discover it blindly.
Supporting receive-only UE for GCSE

4. In the scenario where receives listen the information from command center, UEs may need to maintain radio silence for
critical missions. Therefore, UEs could listen to the group-cast audio channel transmitted from long-rang cell without
registering to the GCSE server by using a preconfigured authorization setting. Moreover, in the current GCSE architecture
in TR 23.768, it requires to routine all group-cast media transports to the GCSE server in EPC and registers all GCSE
members to the GCSE server. Therefore, RP-140185 mentions that the required time for joining an ongoing group
communication may in worse case exceed the requirement of 300 ms. Comparing with the current GCSE architecture, UE
could listen to the group-cast audio channel without registering to the GCSE server. As a consequence, it could quickly join
an ongoing group call anonymously.
Supporting receive-only UE for ProSe
In TR 23703, it mentions that we have to handle out of network coverage scenarios for proximity direct communication in
rural area. Therefore, long-range cell is proposed to reduce network converge holes, and thus the phenomenon can be
significantly mitigated especially in the rural area.
Although, for receivers located in the fringe areas outside the coverage contour can only receive outbound communication,
those UEs can still obtain synchronization signal, system information block, and semi-persistent resource management
information for establishing direct communication. However, the UE relay, which does not need to relay the downlink
traffic in order to efficiently utilize the radio resource, could be used to extend the uplink range using the direct
communication link between UE located inside the coverage contour of the system and UE located in the fringe areas
outside the coverage contour.
[1] LTE The UMTS Long Term Evolution from Theory to Practice Ed2
[2] International Telecommunication Union (ITU), “Radio Communications for Emergency Response and Disaster
Relief” (http://www.itu.int/ITU-D/asp/CMS/Events/2012/NBTC-disaster/S6_MrBhatia.pdf)
4 Objective *
The SA1 objective is to specify service requirements for:
• Allowing E-UTRAN to support receive-only UE for ProSe.
o Handling ProSe Communication when public safety UEs could only receive down-link signaling. The
receive-only UE could obtained UE-to-Network Relay candidates from long range cell instead discover it
blindly.
• Allowing E-UTRAN to support long-range cell operation for GCSE.
o Supporting radio silence feature when joining a group call and shorten required time for joining an ongoing
group call and by using a preconfigured authorization setting.
The scope of the Work Item is limited to Public Safety UEs and Public Safety use.
5 Service Aspects
Service aspects will be specified.
6 MMI-Aspects
Any potential service impacts will be identified.
7 Charging Aspects
Any potential service impacts will be identified.

5. 8 Security Aspects
Security aspects will be identified.
9 Impacts *
Affects: UICC
apps
ME AN CN Others
Yes X X X
No
Don't know X - X
10 Expected Output and Time scale *
New specifications *
[If Study Item, one TR is anticipated]
Spec No. Title Prime rsp.
WG
2ndary rsp.
WG(s)
Presented for
information at
plenary#
Approved at
plenary#
Comments
Affected existing specifications *
[None in the case of Study Items]
Spec No. CR Subject Approved at plenary# Comments
22.278 0199 Support Long Range Cell Operation
for ProSe
SA#64 (June 2014) S1-141010
22.468 0002 Support Long Range Cell Operation
for GCSE
SA#64 (June 2014) S1-141012
11 Work item rapporteur(s) *
Hsuan-Li Lin (x3232.lin@gmail.com)
Institute for Information Industry
12 Work item leadership *
SA1

6. 13 Supporting Individual Members *
Supporting IM name
Institute for Information Industry (III)
ITRI