GSM LCS Overview Assisted GPS Perspective January 11, 2001

Transcription

1 3GPP LCS Workshop London, England January 11 th 12 th 2001 LCS GSM LCS Overview Assisted GPS Perspective January 11,

2 Overview Key GSM LCS Specifications Modes of Operation Network Reference Model Interfaces and Protocols Call Flows High Level End-to-End Broadcast Ls / Lb Open Interface 2

3 Key GSM LCS Standards Stage 1 GSM Functionality and Service Description Stage 2 GSM Network Reference Model Call Flows Positioning Technologies Stage 3 Multiple Specifications New Specifications GSM RRLP and GSM Broadcast GSM and GSM SMLC Interfaces GSM Supplementary Services (MO-LR) Modified Specifications GSM 03.41, GSM 04.08, GSM 04.80, GSM 08.08, GSM

4 Modes of Operation MS- Assisted GPS MS-Assisted GPS is defined as an implementation where assistance data is provided to the MS, by the SMLC, such that the MS can acquire GPS satellite signals and determine their corresponding pseudorange measurements. These time-stamped satellite psuedoranges are returned to the SMLC, where the location estimate is then calculated. MS-Based GPS MS-Based GPS is defined as an implementation where assistance data is provided to the MS, by the SMLC, such that the MS can calculate its own location estimate. 4

5 Network Reference Model 4.31 RRLP and 4.35 Broadcast Messages CBSC CBC-SMLC SMLC 8.71 BSSLAP Messages LCS Client CBC- BSC 3.41 Messages 9.31 BSSAP-LE Messages Lb Ls 9.31 BSSAP-LE Messages Le MS Um 4.08 Messages BSC A 8.08 Messages MSC Lg 9.02 MAP Messages GMLC 4.30 & 4.80 SS Messages End to End Protocol Basic Protocol 5

6 Interfaces and Protocols (1) Um GSM New RR Message Application Information Message Carries RRLP Messages A GSM Essentially a Pipe Lg GSM New Map Messages MAP Subscriber Location Report MAP Provide Subscriber Location Le Not specified, API suggested in GSM J-STD-036 in North America defines one instance of Le 6

7 Interfaces and Protocols (2) Lb / Ls GSM Ls implies NSS based SMLC, Lb implies BSS based SMLC Protocol referred to as BSSAP-LE Perform Location Request / Response Connection Oriented Information Carries RRLP Messages BBSLAP GSM End-to-End protocol between BSC and SMLC Carries radio specific data such as TA RRLP GSM Broadcast GSM

8 NSS Based SMLC Protocol Stacks RRLP RRLP BSSLAP BSSLAP RR RR BSSAP BSSAP BSSAP- LE BSSAP-LE L2 L2 SCCP SCCP SCCP SCCP L1 L1 MTP MTP MTP MTP MS BSC MSC SMLC Um A Ls 8

9 BSS Based SMLC Protocol Stacks RRLP RRLP BSSLAP BSSLAP RR RR BSSAP- LE BSSAP-LE L2 L2 SCCP SCCP L1 L1 MTP MTP MS BSC SMLC Um Lb 9

10 MT Call Flows All MT Call Flows are requests for the MS s current location Supplementary Service mechanisms used for user notification SMLC invoked via a Perform Location Request Contains: Request Type (location estimate), Cell ID, Priority, QoS, Classmark, etc SMLC then sends an RRLP Measure Position Request Message to MS Contains: Instructions regarding mode of operation MS-Assisted or MS-Based preference Some amount of assistance data 10

11 MT Call Flow NSS Based SMLC LCS Client GMLC VMSC SMLC BSC MS 1. LCS Service Request 2. MAP Provide Subscriber Location 3. MS Paging, Auth, & Ciphering 4. LCS Location Notification Invoke 5. LCS Location Notification Return Result 6. BSSMAP-LE Perform Location Request 7. Connection Oriented Information (RRLP) 8. Connection Oriented Information (RRLP) 9. Application Information Message (RRLP) 10. Application Information Message (RRLP) 11. Connection Oriented Information (RRLP) 12. Connection Oriented Information (RRLP) 13. BSSMAP-LE Perform Location Response 14. MAP Provide Subscriber Location Ack 15. LCS Service Response 11

12 MT Call Flow BSS Based SMLC LCS C lient GMLC VMSC SMLC BSC MS 1. LCS Service Request 2. MAP Provide Subscriber Location 3. M S P aging, A uth, & C iphering 4. LC S Location N otification Invoke 5. LC S Location N otification R eturn R esult 6. BSSMAP-LE Perform Location Request 7. BSSMAP-LE Perform Location Request 8. Connection Oriented Inform ation (RRLP) 9. Application Information Message (RRLP) 10. Application Information Message (RRLP) 11. C onnection O riented Inform ation (R R LP ) 12. BSSMAP-LE Perform Location Response 13. BSSMAP-LE Perform Location Response 14. MAP Provide Subscriber Location 15. LCS Service Response 12

13 RRLP Level Generic End-to-End MT Call Flow SMLC MS 1. Measure Position Request ( positioninstruct, referenceassistdata, msrassistdata, systeminfoassistdata, gps-assistdata, extensioncontainer) 2. Measure Position Response (multiplesets, referenceidentity, locationinfo, gps-measureinfo, locationerror, extensioncontainer) 13

14 RRLP Level MS-Assisted MT Call Flow SMLC MS 1. Measure Position Request (Acquisition Assistance and Reference Time (TOW Assist)) 2. Measure Position Response (GPS Measurement Information) 14

15 RRLP Level MS-Based MT Call Flow SMLC MS 1. Measure Position Request (Reference Location and Reference Time (TOW Assist)) 2. Measure Position Response (Lat/Long) 15

16 MO Call Flows Unlike MT Call Flows not all call flows are requests for the MS s current location SMLC invoked via a Perform Location Request Contains: Request Type, Cell ID, Priority, QoS, Classmark, etc There are three types of MO Call Flows The MS can request: Location Estimate Assistance Data Ciphering Keys Supplementary Service mechanisms used to specify service request and to return location estimate if requested 16

17 MO Call Flow NSS Based SMLC LCS Client GMLC VMSC SMLC BSC MS 1. CM Service Request 2. BSSMAP CM Service Request 3. Auth, Ciphering, or CM Service Accept 4. LCS M O -LR Invoke 5. BSSMAP-LE Perform Location Request 6. Connection Oriented Information (RRLP) 7. Connection Oriented Information (RRLP) 8. Application Information Message (RRLP) 9. Application Information Message (RRLP) 10. Connection Oriented Information (RRLP) 11. Connection Oriented Information (RRLP) 12. BSSMAP-LE Perform Location Response 13. MAP Subscriber Location Report 14. MAP Subscriber Location Report Ack 15. LCS Service Response 16. LCS MO-LR Return Result 17. Release CM, MM, RR Connections 17

18 MO Call Flow BSS Based SMLC LCS Client GMLC VMSC SMLC BSC MS 1. CM Service Request 2. BSSMAP CM Service Request 3. Auth, Ciphering, or CM Service Accept 4. LCS MO-LR Invoke 5. BSSMAP-LE Perform Location Request 6. BSSMAP-LE Perform Location Request 7. Connection Oriented Inform ation (RRLP) 8. Application Inform ation Message (RRLP) 9. Application Inform ation Message (RRLP) 10. Connection Oriented Inform ation (RRLP) 11. BSSMAP-LE Perform Location Response 12. BSSMAP-LE Perform Location Response 13. MAP Subscriber Location Report 14. MAP Subscriber Location Report Ack 15. LCS Service Response 16. LC S M O -LR R eturn R esult 17. Release CM, MM, RR Connections 18

19 Location Estimate MO Call Flow MS-Assisted SMLC VMSC BSC MS 1. LCS MO-LR Invoke (Req Loc Est) 2. BSSMAP-LE Perform Location Request (Req Loc Est) 3. Measure Postion Request (Assumed Assistance Data) 4. Measure Postion Response (GPS Measurement Info) 5. BSSMAP-LE Perform Location Response (Lat/Long) 6. LCS MO-LR Return Result (Lat/Long or Ack) 19

20 Location Estimate MO Call Flow MS-Based SMLC VMSC BSC MS 1. LCS MO-LR Invoke (Req Loc Est) 2. BSSMAP-LE Perform Location Request (Req Loc Est) 3. Measure Position Request (Assumed Assistance Data) 4. Measure Position Response (Lat/Long) 5. BSSMAP-LE Perform Location Response (Lat/Long) 6. LCS MO-LR Return Result (Lat/Long or Ack) 20

21 Assistance Data MO Call Flow SMLC VMSC BSC MS 1. LCS MO-LR Invoke (Req Assistance Data) 2. BSSMAP-LE Perform Location Request (Req Assistance Data) 3. Assistance Data (Assistance Data) 4. Assistance Data () 5. BSSMAP-LE Perform Location Response () 6. LCS MO-LR Return Result () 21

22 Ciphering Keys MO Call Flow SMLC VMSC BSC MS 1. LCS MO-LR Invoke (Req Ciphering Keys) 2. BSSMAP-LE Perform Location Request (Req Ciphering Keys) 3. BSSMAP-LE Perform Location Response (Ciphering Keys) 4. LCS MO-LR Return Result (Ciphering Keys) 22

23 Incomplete Assistance Data In cases where the SMLC initially sends incomplete assistance data to the MS, the MS can request an explicit set of assistance data The SMLC will then repeat the Measure Position Request message with the requested assistance data 23

24 Incomplete Assistance Data Call Flow SMLC MS 1. Measure Position Request (Reference Location and Reference Time (TOW Assist)) 2. Measure Position Response (Error Message and Request for Navigation Model) 3. Measure Position Request (Navigation Model) 4. Measure Position Response (Lat/Long) 24

25 Broadcast There are three types of broadcast GPS assistance data: Differential GPS corrections (including Reference Time and Reference Location), Ephemeris and clock correction, and Almanac and other data. The call flow is generic for both MS-Based and MS- Assisted implementations The GPS Assistance Data Broadcast Message is created in the SMLC and the whole message is transferred from the SMLC to the MS 25

26 Broadcast Call Flow CBC SMLC BSC BTS MS 1. LCS Broadcast Data(data & parameters) 2. SMSCB messages between CBC BSC BTS described in GSM LCS Broadcast Data Response 4. LCS Broadcast Data(data) message from BTS to MS described in GSM

27 Ls / Lb Open Interface BSSAP-LE Messages Perform Location Request / Response Connection Oriented Information Perform Location Request specifies request type Location Estimate Assistance Data Ciphering Keys Connection Oriented Information Message Contains a BSSLAP Message, which contains the RRLP Message BSSLAP messages also carry radio specific information such as TA 27

28 Perform Location Request Information element Type / Reference Presence Format Length in octets Message type Message Type M V 1 Location Type Location Type M TLV 4 Cell Identifier Cell Identifier M TLV 3-10 Classmark Information Type 3 Classmark Information Type 3 O TLV 2-n LCS Client Type LCS Client Type O TLV 3 Chosen Channel Chosen Channel O TLV 2-n LCS Priority LCS Priority O TLV 3 LCS QoS LCS QoS O TLV 6 GPS Assistance Data GPS Assistance Data O TLV 3-n BSSLAP APDU APDU O TLV 2-n 28

29 Perform Location Response Information element Type / Reference Presence Format Length in octets Message type Message Type M V 1 Location Estimate Geographic Location C TLV 2-22 Positioning Data Positioning Data O TLV 2-n Deciphering Keys Deciphering Keys O TLV 10-n LCS Cause LCS Cause O TLV 3 29

30 Connection Oriented Information Information element Type / Reference Presence Format Length in octets Message type Message Type M V 1 BSSLAP APDU APDU M TLV 3-n Segmentation Segmentation C TLV 3 30