Content for TS 36.459 Word version: 18.0.0
1 Scope
2 References
3 Definitions, symbols and abbreviations
3.1 Definitions
3.2 Symbols
3.3 Abbreviations
4 General
4.1 Procedure Specification Principles
4.2 Forwards and Backwards Compatibility
4.3 Specification Notations
5 SLmAP Services
6 Services Expected from Signalling Transport
7 Functions of SLmAP
...
...
1 Scope p. 6
The present document specifies the E-UTRAN radio network layer signalling protocol for the SLm interface. The SLm Application Protocol (SLmAP) supports the functions of the SLm interface by signalling procedures defined in this document. SLmAP is developed in accordance to the general principles stated in TS 36.305 and TS 36.456.
2 References p. 6
The following documents contain provisions which, through reference in this text, constitute provisions of the present document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.
[1]
TR 21.905: "Vocabulary for 3GPP Specifications".
[2]
TS 36.305: "Stage 2 functional specification of User Equipment (UE) positioning in E-UTRAN".
[3]
TS 36.456: "Evolved Universal Terrestrial Radio Access Network (E-UTRAN); SLm interface general aspects and principles".
[4]
TS 36.455: "LTE Positioning Protocol A (LPPa)".
[5]
TS 36.101: "User Equipment (UE) radio transmission and reception".
[6]
TS 23.032: "Universal Geographical Area Description (GAD)".
[7]
TS 36.413: " Evolved Universal Terrestrial Radio Access Network (E-UTRAN); S1 Application Protocol".
[8]
ITU-T Recommendation X.691 (2002-07): "Information technology - ASN.1 encoding rules - Specification of Packed Encoding Rules (PER)".
[9]
TS 36.111: "Location Measurement Unit (LMU) performance specification; User Equipment (UE) positioning in E-UTRAN".
[10]
TS 36.104: "Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Base Station (BS) radio transmission and reception".
[11]
TS 36.211: "Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Physical Channels and Modulation".
3 Definitions, symbols and abbreviations p. 6
3.1 Definitions p. 6
For the purposes of the present document, the terms and definitions given in TR 21.905 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905.
Elementary Procedure:
SLmAP consists of Elementary Procedures (EPs). An Elementary Procedure is a unit of interaction between LMUs in the E-UTRAN and E-SMLCs in the EPC. These Elementary Procedures are defined separately and are intended to be used to build up complete sequences in a flexible manner. If the independence between some EPs is restricted, it is described under the relevant EP description. Unless otherwise stated by the restrictions, the EPs may be invoked independently of each other as standalone procedures, which can be active in parallel. The usage of several SLmAP EPs together or together with EPs from other interfaces is specified in stage 2 specifications (e.g., TS 36.305).
An EP consists of an initiating message and possibly a response message. Two kinds of EPs are used:
- Class 1: Elementary Procedures with response (success and/or failure).
- Class 2: Elementary Procedures without response.
- A signalling message explicitly indicates that the elementary procedure successfully completed with the receipt of the response.
- A signalling message explicitly indicates that the EP failed.
- On time supervision expiry (i.e., absence of expected response).
- One signalling message reports both successful and unsuccessful outcome for the different included requests. The response message used is the one defined for successful outcome.
3.2 Symbols p. 7
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3.3 Abbreviations p. 7
For the purposes of the present document, the abbreviations given in TR 21.905 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905.
LMU
Location Measurement Unit
SLmAP
SLm Interface Application Protocol
SRS
Sounding Reference Signal
TNL
Transport Network Layer
UL RTOA
Uplink Relative Time of Arrival
UTDOA
Uplink Time Difference of Arrival
4 General p. 7
4.1 Procedure Specification Principles p. 7
The principle for specifying the procedure logic is to specify the functional behaviour of the terminating node exactly and completely. Any rule that specifies the behaviour of the originating node shall be possible to be verified with information that is visible within the system.
The following specification principles have been applied for the procedure text in clause 8:
-
The procedure text discriminates between:
- Functionality which "shall" be executed The procedure text indicates that the receiving node "shall" perform a certain function Y under a certain condition. If the receiving node supports procedure X but cannot perform functionality Y requested in the REQUEST message of a Class 1 EP, the receiving node shall respond with the message used to report unsuccessful outcome for this procedure, containing an appropriate cause value.
- Functionality which "shall, if supported" be executed The procedure text indicates that the receiving node "shall, if supported," perform a certain function Y under a certain condition. If the receiving node supports procedure X, but does not support functionality Y, the receiving node shall proceed with the execution of the EP, possibly informing the requesting node about the not supported functionality.
- Any required inclusion of an optional IE in a response message is explicitly indicated in the procedure text. If the procedure text does not explicitly indicate that an optional IE shall be included in a response message, the optional IE shall not be included. For requirements on including Criticality Diagnostics IE, see clause 10.
4.2 Forwards and Backwards Compatibility p. 8
The forwards and backwards compatibility of the protocol is assured by mechanism where all current and future messages, and IEs or groups of related IEs, include ID and criticality fields that are coded in a standard format that will not be changed in the future. These parts can always be decoded regardless of the standard version.
4.3 Specification Notations p. 8
For the purposes of the present document, the following notations apply:
Procedure
When referring to an elementary procedure in the specification the Procedure Name is written with the first letters in each word in upper case characters followed by the word "procedure", e.g., E-RAB procedure.
Message
When referring to a message in the specification the MESSAGE NAME is written with all letters in upper case characters followed by the word "message", e.g., MESSAGE NAME message.
IE
When referring to an information element (IE) in the specification the Information Element Name is written with the first letters in each word in upper case characters and all letters in Italic font followed by the abbreviation "IE", e.g., Information Element IE.
Value of an IE
When referring to the value of an information element (IE) in the specification the "Value" is written as it is specified in subclause 9.2 enclosed by quotation marks, e.g., "Value".
5 SLmAP Services p. 8
SLmAP provides the signalling service between E-SMLC and the Location Measurement Unit (LMU) that is required to fulfil the SLmAP functions described in clause 7. The procedures are divided into two groups:
- UTDOA Measurement Information Transfer procedures;
- SLm Interface Management procedures.
6 Services Expected from Signalling Transport p. 8
The signalling connection shall provide in sequence delivery of SLmAP messages. SLmAP shall be notified if the signalling connection breaks.
7 Functions of SLmAP p. 8
The SLmAP protocol has the following functions:
- Measurement Information Transfer. This function allows the E-SMLC to exchange measurement information with the LMU for the purpose of UTDOA positioning.
- SLm interface management. This function allows initialization of the SLm interface and exchange of capability information between the E-SMLC and LMU.
- Reporting of general error situations. This function allows proper error reporting and handling.
| Function | Elementary Procedure(s) |
|---|---|
| Measurement Information Transfer | a) Measurement
b) Measurement Update c) Measurement Abort |
| SLm Interface Management | a) SLm Setup
b) Reset |
| Reporting of general error situations | Error Indication |
