Creativity Software

Location Based Applications and Services

Location services cover a wide range of services, orientated at individual users or devices and vehicles. These can include:

• “Find Me” services e.g. nearest restaurant, coffee bar, ATM etc
• Location based charging, for example ‘Home Zone’ or ‘Office Zone’
• Retail offers - dependant on user proximity
• Social networking services
• Visitor local information services
• Child find/locate services
• Route planning/navigation
• “Where am I” type information services
• Location based games
• Vehicle and asset tracking
• Support for emergency services and lawful intercept.

Such applications may be supported within a mobile operator’s network, or externally via third parties. In both cases, the application which depends on information obtained and processed by network resources is referred to as an LCS Client.

Location Techniques

The location of the UE is defined in terms of latitude and longitude coordinates. The accuracy depends on the particular technique used to locate the mobile. Several mobile (GSM) industry variants are currently deployed. The method for ‘requesting’ a user’s mobile location and the resultant network generated messages are standardised for GSM regardless of the location technique utilised.

The ability of a mobile network to establish the location of UE is essential to ensure incoming calls are ‘directed’ to the appropriate cluster or group of cells. Such clusters or groups are defined/known as Location Areas. To ensure consistent call management, mobiles continually assess and measure the radio parameters from surrounding / neighbouring cells and detect when moving from one cell area (LAC) to another, in close co-ordination with the radio access network and base station infrastructure. Using this information, it is possible to ‘triangulate’ the geographic position of a user mobile. There are three primary data sets that can be used to cost-effectively locate the position of UE equipment without significant overhead. These are:

• Cell ID
• Cell ID + Timing Advance (TA) (CITA)
• Cell ID + TA + Relative Signal Strength (RxLEV) (CITARx)

The different levels of accuracy are illustrated in the diagram.

Infrastructure Required

In order to capture the information required for determining the location of UE and to control the management of authorised requests from LCS client applications to access the data requires the deployment of two dedicated nodes in mobile networks: the Gateway Mobile Location Centre (GMLC) and the Serving Mobile Location Centre (SMLC). This is illustrated below.

Figure 1 –The addition of the GMLC and SMLC nodes to provide location based services within a GSM frame work	Figure 2 – Figure extracted from 3GPP TS 03.71 Figure 3 page 20 describing the core element and interfaces in between.

The general architecture for the provision of location services is illustrated in Figure 1. Two additional logical entities are provisioned. The Gateway Mobile Location Centre (GMLC) and the Serving Mobile Location Centre (SMLC). Figure 2 highlights how this logical arrangement maps into the architecture specified by 3GPP for GSM and derivative networks. For networks derived from the CDMA family of standards, there are two equivalent nodes, the MPC and PDE.

The Complete Solution from Creativity Software

Creativity Software is able to provide a turnkey solution to Location Based services, offering:

• Infrastructure
• Middleware
• Applications

Creativity software has adopted a standards based approach to ensure compliance with 3GPP / 3GPP2 specifications. For example, the detailed message flow for a location transaction can be viewed here.

By offering dedicated solutions to each layer of the “stack”, Creativity Software can support any infrastructure and interoperate with third party equipment at all levels. Customers can be assured that a Creativity Software solution addresses all needs for a reliable, scalable and high-performance location services architecture.