US 8,428,031 B2 · Method and apparatus for facilitating handover from a WCDMA public land mobile access network to a generic access network

Abstract

Handover is improved from a 3 G WCDMA UTRAN to a generic access network (GAN) cell. For handover, mobile stations measure signal level from neighbor cells. In a WCDMA UTRAN, measurement of cells having a frequency number different from the serving cell, require the network to generate time gaps so the mobile station can perform measurements on different frequencies. GAN cells do not transmit on their allotted frequency number. This number together with an identifier is used to identify the GAN cell between the MS and RNC. A modified registration procedure permits GAN cells to always have the same frequency number as neighboring UTRAN cells, wherein the MS communicates the current UTRAN cell frequency number to the GAN controller, which adopts this number, and determines the corresponding identifier. The identifier may be the same for all GAN cells, or can be obtained from a mapping table, which maps an identifier to each frequency.

Claims11

Dependent claims

A method of facilitating handover of an active call or packet session conducted between a mobile station and a WCDMA public land mobile network via a public land mobile network cell controlled by a radio network controller from said public land mobile network cell to an unlicensed access network cell that is served by an unlicensed access network controller connected to said WCDMA public land mobile network, said method including the steps of

in said unlicensed access network controller, receiving a register request message from said mobile station, said register request message including a frequency number indicative of a radio frequency used in said public land mobile network cell and extracting from said register request message said frequency number,
adopting said frequency number as an identifying frequency for said unlicensed access network controller in said public land mobile network cell to enable the mobile station to report a signal strength for said unlicensed access network cell to radio network controller without indicating a radio frequency that is different from that used in public land mobile network cell, and
sending a register accept message to said mobile station, said register accept message including information indicative of said adopted frequency together with an identifier for said unlicensed access network controller.

An unlicensed access network controller adapted to provide access to at least one WCDMA public land mobile network for mobile stations located within unlicensed access network cells controlled by said unlicensed access network controller and to accept handover of active calls or packet sessions conducted between mobile stations with one of said public land mobile networks via a public land mobile network cell controlled by a radio network controller,

said unlicensed access network controller comprising a processor associated with a non-transient memory storing instructions that cause the unlicensed access network controller to:
receive a registration request message from a mobile station prior to handover, said registration request including information identifying a current public land mobile network cell serving said mobile station and a frequency number of the said current serving public land mobile network cell,
adopt said frequency number in combination with an identifying code as an identifier for an unlicensed access network cell capable of accepting handover of an active call or packet session with said mobile station from said current public land mobile network cell, and
transmit a registration accept message including said frequency number and said identifier to said mobile station.

1 more element

Dependencies are inferred from the claim text.

Method and apparatus for facilitating handover from a WCDMA public land mobile access network to a generic access network

Life of this patent

Method and apparatus for facilitating handover from a WCDMA public land mobile access network to a generic access network

Life of this patent

Abstract

Claims11