Management of Outdoor Location Technologies

Jose María Carazo Cepedano josecarazoc@gmail.com

es.linkedin.com/in/josemariacarazo/en

Most Common Outdoor Location Technologies

Access through MNO’s LBS Infrastructure: General Schema LBS Architecture LBS Functions & Services

Access through mobile client components: General schema External Network Providers Global Network Server

Comments & Conclusions

Contents

Technologies CellId A-GPS WiFiGeneral -From 2G to 3.5G networks

-4G (LTE): Currently adopted/ported by many MNOs . Location under testing

- GPS, GLONASS, Galileo - Private/Public Wifi networks

Based on -Server Cell (CGIId) - CGI-TA (Timing Advanced)- RxLev (Signal strenght) - Neighbors cells (NMR/BSIC) (triangulation/trilateration)- Other approaches: TOA, AOA, E-TDOA, E-OTD

- Signal from, at least, 3 visible satellites - Ephemerides /Navigation DB- ToA + Filters

- MAC Adresss - RxLevel - Several networks (triangulation)

Accuracy -Depends on cell type (femtocells, picocells, micro, macro)-Depends on density of antennas- Usual figures:

- From 60 m to 800 m in urban env.- From 1 km to 25 kms in rural env.

-TTFF concept-Depends on number of visible satellites and device capabilities (antenna and chipset installed)- Data provided from Assistance server (SUPL Positioning Server) -Typically from 3 to 10 m

-Depends on signal power-Typically from 50 m to 200 m

Indoor notes - DAS Systems and Picocells could be possible approaches

- Next generation (GPS III) will be more accurate covering urban canyons but it won’t cover indoor env.

- Indoor WiFi requires other mechanisms that are not included in this doc.

Most Common Outdoor Location Technologies

These location technologies can be accessed through Operator’s LBS infrastructure as well through client components installed in the mobile device

E-CGI

Network

LBS

Le interface

Access through MNO’s LBS infrastructure – General Schema

Service Delivery Platform (SDP)

LBS

Other M

NO

’s system

s/capacities

SS7/MAP msgs ULP msgs

Location Enabling Server (LES)

Location System (LS)

SDP (Service Delivery Platform): Optional platform. Provides a public access point to MNO’s infrastructure establishing the appropriate call flow for each incoming request - i.e Huawei SDP

LES (Location Enabling Server): Most of big Operators have installed this middleware as the central piece of the LBS infrastructure - i.e Genasys Positioning Platform

Le Interface: Many Operators offer a public API for ASPs/LBS providing CGI+TA technology (Control Plane Arch.). Some Operators provide also A-GPS technology (SUPL Arch.) - i.e. OMA MLP

LS (Location System): Mandatory piece. Provides the location engine to get the user’s position based on its MSISDN/IMSI. It uses SS7 signaling channels to access MNO’s network (HLR/VLR for CGI techno.). Under SUPL arch. this server is called SLP (SPC+SLC) and interacts directly with the handset (SET) through Lup interface - i.e Geolens from Commscope.

GMLC SLP

SET

SMS-C

MMS-C

WAP GW

WEB Portal

IVR

Billing Systems (Pre/PostPaid)

Provisioning System

O&M

Customer Care

Statistic & Datawarehouse

Network Info DB

SSO

Terminal Info DBPresence Server

GIS/GeoServer

MNO’s LBS infrastructure can include a wide variety of systems and components. Each installation requires specific plug-ins with the existing external systems: O&M,

Media GWs, Provisioning, Billing,.. and others LBS systems. These plug-ins must develop the interface (std or proprietary) as well the MNO’s required

logic . LES and LS systems must be prepared to allow all these adaptations as flexibly as possible.

Access through MNO’s LBS infrastructure – LBS Architecture

Security/Access Ctrl Mgmt

Single/Hybrid Location Engine

Public/Private API

User Subscription Mechanisms

Privacy Mgmt

Cache Mgmt

Admin./Config. Tools

There are a set of specific functions that must be supported by the MNO’s LBS infrastructure:

• Full set of API services including:- Location: Immediate, Tracking, Geo-fencing, Around,…- Provisioning of users and groups- Messaging (SMS,MMS,USSD,…)

- Spatial (mapping, routing, direct/reverse geocode, POI searching, …)

• Authentication & Authorization of requests• User’s subscription: Auto provisioning, Initiated by user or App, with/without user’s ack,…• Privacy: Anonymous ID, MSISDN masking,, when, where and who can request the location.• Location Cache: Last known location per user and per loc. Technology, max loc. Age per app.• Intelligent switching between available loc. technologies• Admin. WEB Tools: Provisioning, Statistic and System Configuration tools.

Location Enabling Server (LES)

Location System (LS)

Access through MNO’s LBS infrastructure – LBS Functions/Services

Most of these advanced features are usually carried out by the LES middleware being

compliant with the specific rules and policies of each MNO

LBSLBS

Location API

Security/Privacy Mgmt

Cache/QoP Mgmt

Server SystemSMS /GPRS

• Through API functions & SDKs that every O.S provides is the possibility to access the necessary network parameters (MCC-MNC-LAC-CI, SSID/MACAddress, RxLev, …) as well as the GPS data (Lat/Lon coordinates, speed and direction).

• The client component can offer a public API for installed apps in the handset as well as external requests from the server side. This public API could provide:

- Immediate location function- Tracking under several modes (periodic time,

when cell change event occurs, when some distance has been reached, …)

- Geo fencing capabilities

• This location component could have other additional capabilities for security and privacy purposes, policies to decide between available technologies and intelligent self-learning.

CGI WiFi

A-GPS

BTLE

NFC

LBSLBS

Client Component

Access through MNO’s LBS infrastructure – General Schema

This client component could be offered to Mobile Operators in a cooperative way within

the LES/LS systems.

• If this component is outside of the MNO’s environment, a system is required that converts the network information into geographic coordinates.

• This kind of system/DB is provided currently by several vendors like the following : o Googleo Navizono RxNetworkso Combain (location-api)o Broadcom

• These network providers offer a simple API to convert network data - GSM/UMTS, WiFi networks and/or IP location - into Lat/lon/radius values.

Location API

Security/Privacy Mgmt

Cache/QoP Mgmt

Server System

SMS /GPRS

Client Component

Network Provider

Access through MNO’s LBS infrastructure – External Network Providers

• The prices of this connection depends on the number of hits per month, the type of technology required and/or the desired geographical area.

• The request to this conversion service can be done both from the client component or the server side.

• The schema shows a global server system that maintains the connection with multiple network providers (NP) such as:

• Improve the success resolution rate of the conversion process worldwide and for all Mobile Operators.

• Provide all the benefits and capabilities of each external provider under a single, homogeneous and advanced interface.

• Maintain all data (solved and errors) in an internal cache avoiding unnecessary requests.

• Establish periodic tests over each external provider giving a level of quality, reliability and accuracy. These values will determine policy decisions based on, for instance:

• The type of network technology (WiFi, 2G, 3G, ....)

• The geographical area (country, city ...)• The associated Operator

Network Provider

Global Network Data Server

Advanced API

Cache Mgmt

Network Provider

Network Provider

Client Components

Server Systems

Decission Policies

Access through MNO’s LBS infrastructure – Global Network Server

Comments & Conclusions (I)1) About CGI• The LS (MNO’s system) uses the private BTS DB of the Operator in order to evaluate

the final user’s position.• In this DB, each CGIId register contains their X/Y coordinates , a coverage area and

additional radio electric parameters (antenna height/down tilt,power, horizontal beam opening,…).

• The antenna coverage area has been calculated through empiric algorithms (UIT Rec) within a data model of terrain (MDT) and taking into account the interferences between sites.

• This BTS DB is maintained by the MNO’s Network team being usually highly dynamic.• The daily changes that the MNO does over their network does not usually reflect

coherently over its BTS DB so it loses quality and reliability in their LBS services (directly or indirectly supported).

• On the other hand, the BTS DB that has been collected by the external network providers (NP) has reached a high quality as they now have a lot more devices (cars/handsets) and have improved their hybrid algorithms (GPS+WiFi+CGI measurements ) establishing a more realistic coverage area from each antenna.

• However, the NP has no immediate knowledge in its DB of all the MNO’s network changes (new antennas, updates in existing ones,…).

Comments & Conclusions (II)

1) About CGI (cont)• As the Network Provider does, the operator could facilitate the same network

conversion service using their own BTS DB.• The operator could take advantage of the work done by these Network Providers

through a full scan of each CGIId against the external conversion service.• Using their private data (site coordinates, power, azimuth radiation, beam opening,

etc) along with circular coverage returned by the Network Provider , it is possible to determine a more exact coverage area of each cell.

• Moreover the operator keeps records of all user events through billing information (CDRs) or network events (attach, detach, On / Off, ...).

• Keeping all this mass of information of movements about all MNO’s subscribers could be complicated from the point of view of the Network Provider so the Operator can have the ability to lead solutions such as:• Emergency (112/911)• Public warning systems (alert the population located in an emergency area)• Traffic Incident Management

Comments & Conclusions (III)

2) About WiFi• Many operators have a Hotspot BD with exact information about public and private

access points. • These DB could be much more accurate than those established by the Network

Providers through their mapping processes. The Operator can get the exact address where each customer has installed their routers (including which floor).

• However there are few operators offering this technology under public access.

3) About GPS/A-GPS• Due to many tests and certifications of each mobile terminal, the Operator has had a

long delay in including this technology under their LBS infrastructure.• Based on that, the public use of this technology is further consolidated through

individual client applications (maps viewers, navigation, POI searching and augmented reality, etc).

Comments & Conclusions (IV)

• Under the outdoor scenario, it seems that the established order and priorities by the existing components is to first try to get the CGI techno., then WiFi and finally access the GPS as the most precise technology.

• The CGI technology, by itself, is still a valid technology for many applications and services.

• The access to the CGI parameters does not consume any significant resources or battery in the mobile device (being an alternative technology) when access to GPS / WiFi is not needed.

• For example, under geo fencing logic, you can keep a continuous track under CGI technology while the user is far from the alarm area switching to a more precise technology when he/she is closest.

• Maybe, the most suitable way for a Mobile Operator (or for a handset manufacturer) is the formalization of a generic component that could be preinstalled on their terminals.

• This client component would enable the use of all available location technologies for any LBS application (both local and external to the device) and should be prepared to support indoor positioning technologies (Indoor WiFi, BTLE,…) in the near future.

• Finally, in the indoor world, the Operator may be an additional player through DAS solutions, IP location and femto cells.

Any questions?

I’m happy to help you!