KR200428610Y1 - System for supporting an evolved utran - Google Patents

Abstract

A system for supporting an advanced Universal Mobile Telecommunication System (UMTS) Terrestrial Radio Access Network (E-UTRAN) is disclosed. The system includes a wireless transmit / receive unit (WTRU), UTRAN and E-UTRAN. The UTRAN sends to the WTRU a list of radio access technologies available in the coverage area of the UTRAN. The list contains information related to the E-UTRAN. Next, the WTRU sends its multi-mode / multi-RAT capability information to the UTRAN including the E-UTRAN capability. Next, the UTRAN sends a measurement capability message to the WTRU. The measurement capability message contains the parameters needed to make measurements for the E-UTRAN channel. The WTRU performs measurements based on the measurement capability message and reports the measurement results to the UTRAN. The UTRAN may start handoff to the E-UTRAN based on the measurement results.

UTRAN, E-UTRAN, Wireless Access, Mobile Communication Systems, WTRU

Description

System supporting advanced terrestrial radio access network {SYSTEM FOR SUPPORTING AN EVOLVED UTRAN}

1 is a diagram of a conventional wireless communication system.

2 illustrates a wireless communication system constructed in accordance with the present invention.

3 is a flow chart of a process supporting E-UTRAN according to the present invention.

<Explanation of symbols for the main parts of the drawings>

200: wireless communication system 220: core network

230: PSTN 240: Internet

250: WTRU

The present invention relates to a wireless communication system. More specifically, the present invention relates to a method and system for supporting an evolved universal mobile telecommunication system (UMTS) terrestrial radio access network (E-UTRAN).

Different kinds of wireless access systems have been developed to provide different kinds of services and capabilities. Some examples of wireless access systems include wireless local area network (WLAN) (IEEE 802-based networks, etc.), and cellular networks [UMTS terrestrial radio access network (UTRAN)], enhancements for global communications (GSM) / GSM evolution for mobile communications. Data rate (EDGE) radio access network (GERAN) and the like. Each of these networks has been developed and tailored to provide specific applications.

Long Term Evolution for UTRAN and Evolved Node-B (E-Node-B) have been proposed to improve wireless system capabilities and improve performance. E-UTRAN will offer significant advantages over existing wireless communication systems and additional services will be possible through the high bit rate and low latency provided by E-UTRAN. 1 illustrates a conventional integrated wireless communication system 100 that includes an E-UTRAN 114. The system 100 includes an access system layer 110, a network layer 120, and a multimedia layer 130. The access system layer 110 includes a plurality of radio access networks (RANs) 111-115, a core network (CN) 116, and an advanced CN 117. The RANs 111-115 may include a generic access network (GAN) 111, a GERAN 112, a UTRAN 113, an E-UTRAN 114 and an interworking wireless local area network (I-WLAN) ( 115). RANs 111-115 are connected to CN 116 or advanced CN 117 to provide services (eg, multimedia services from Internet Protocol (IP) Multimedia Subsystem (IMS) 131); Authentication, authorization and accounting (AAA) server in network layer 120 via gateway General Packet Radio Service (GPRS) support node (GGSN) 118 or packet data gateway (PDG) 119 121, is connected to one or more WTRUs while interacting with mobile IP (MIP) server 122 or other network entities.

Currently, multimode wireless transmit / receive units (WTRUs) configured to support multiple wireless communication systems are available. The capabilities of each of the WTRUs may vary. For example, some WTRUs may only support UMTS, while others may support multiple modes of operation, such as I-WLAN, GERAN and / or E-UTRAN. WTRUs that can support E-UTRAN will also be available in the future.

It would therefore be desirable to provide a method and system that supports E-UTRAN such that the WTRU may receive and use additional E-UTRAN capabilities and services.

The present invention relates to a system supporting E-UTRAN. The present invention extends conventional methods and procedures to support multimode operations within the wireless communication system to support the addition of a new technology (ie, E-UTRAN) to a UMTS-based wireless communication system (ie UTRAN). . Conventional procedures are specified in the 3rd Generation Partnership Project (3GPP) technical standard (eg TS25.331). Wherein the system comprises WTRU, UTRAN and E-UTRAN. The conventional UTRAN sends a list of radio access technologies (RATs) available in the coverage area of the UTRAN to the WTRU. The list includes information related to existing RAT attributes such as technology type, bit rate, bandwidth, and the like. The present invention introduces information related to E-UTRAN into this list. The WTRU receives this list during the initial connection or during the handoff procedure. Upon receiving the list, an E-UTRAN capable WTRU may configure / reconfigure the WTRU to receive E-UTRAN services based on the list through a handoff procedure or a system reselection procedure. The E-UTRAN capable WTRU may send its multi-mode / multi-RAT capability information, including the E-UTRAN capability, to the UTRAN during initial connection (ie, attach procedure) or when required by the system. . During a normal handoff procedure, the UTRAN sends a measurement capability message to the WTRU. The measurement capability message contains the parameters needed to make measurements for the E-UTRAN channel. The WTRU performs measurements based on the measurement capability message and reports the measurement results to the UTRAN. The UTRAN may start handoff to the E-UTRAN based on the measurement results. In an idle operation, the WTRU may determine to reselect the E-UTRAN based on capability information previously received from the UTRAN. The WTRU uses this information to configure the transmitter and receiver bandwidths, bit rates, frequency bands, and the like.

In the following, the term “WTRU” includes but is not limited to user equipment, mobile stations, fixed or mobile subscriber units, pagers, or other kinds of devices capable of operating in a wireless environment.

Features of the present invention may be integrated into an integrated circuit (IC) or may consist of a circuit having a plurality of wiring components.

2 shows a wireless communication system 200 constructed in accordance with the present invention. The system 200 includes a plurality of RANs 210a, 210b, core network 220, which may be an All Internet Protocol (IP) network (AIPN) disposed under different RATs. The core network 220 is connected to other networks such as a public switched telephone network (PSTN) 230, the Internet 240, and the like. Each of the RANs 210a and 210b may be a GAIN, GERAN, UTRAN, E-UTRAN, IEEE based I-WLAN, or other type of radio access network.

To optimize mobility between the various RANs 210a and 210b, the core network 220 provides an open interface for mobility management (MM) 222 so that the operator of the core network 220 is best suited for the RANs 210a. , 210b may be directed to supervise the WTRU 250. The core network 220 also provides an open interface that allows the WTRU 250 to access other AIPN services, such as session control (SC) 224, AAA 226, and policy control 228.

WTRU 250 is a multi-mode WTRU equipped with at least two radio units configured to support communication with at least two different RATs. For example, the WTRU 250 may include one radio unit for communicating with the E-UTRAN and another radio unit for communicating with the I-WLAN. The WTRU 250 may establish a connection with one of the RANs and perform a handoff to the target if the handoff criteria are met by the target RAN.

Handoff may be initiated manually or automatically in system 200. In the manual handoff process initiated by the user of the WTRU 250, the user knows the presence of alternative RATs (such as E-UTRAN) in its current geographic location (ie, between UTRAN and E-). Switching between UTRANs). The automatic handoff process may be initiated by the WTRU 250 or by the RAN 210a, 210b or the core network 220.

At the handoff initiated by the WTRU, the WTRU 250 detects the presence of alternative RATs (such as the E-UTRAN) and, based on the user's preferences of the WTRU 250, the handoff process (eg, to the E-UTRAN). Start). The WTRU 250 receives necessary information (such as handoff policy, resource status, etc.) from the network (eg, the RAN 210b or the core network 220). The WTRU 250 tracks the locations of the coverage areas of the RANs 210a and 210b and initiates a handoff process based on certain handoff criteria.

In a handoff initiated system, the core network 220 (or RAN 210a, 210b) recognizes that the WTRU 250 can support multiple RTAs (including E-UTRAN) and needs from the WTRU 250. Ask for information (such as power measurements). The core network 220 (or RAN 210a, 210b) tracks the location of the WTRU 250, and once the WTRU 250 is within the coverage area of the target RAN, a set of criteria (mobility of the WTRU 250) , Handoff procedure, based on the required bandwidth, application, load balancing, subscriber's profile, measurement reports provided by the WTRU 250, and the like.

3 is a flowchart of a process for supporting E-UTRAN according to the present invention. The WTRU 352 listens to the channel (eg, broadcast control channel (BCCH)) over the UTRAN 354 (step 302). The UTRAN 354 sends (or indicates) to the WTRU 352 a list of available RATs (such as the E-UTRAN 356 RAT) within the coverage area of the UTRAN 354 (step 304). The list of available RATs is preferably transmitted via a UTRAN cell information list message. However, the list may be transmitted via any kind of message.

The UTRAN cell information list message includes information about intra-frequency cells, inter-frequency cells and inter-RAT cells. The conventional UTRAN cell information list message is modified to include new information elements (IEs) for the E-UTRAN 356. The E-UTRAN 356 may be based on Orthogonal Frequency Division Multiplexing (OFDM), or any other kind of air interface. In the OFDM case, the UTRAN cell information list may include OFDM selection and reselection information, base transceiver station identification code (BSIC), system specific measurement information, and the like. The system specific measurement information lists the supported frequencies, bandwidths, output power and the like. Table 1 shows an exemplary UTRAN cell information list message including new IEs (in bold) according to the present invention.

Referring again to FIG. 3, the WTRU 352 receives the list and stores it (step 306). Based on the preset user preferences, the WTRU 352 sends its multi-mode / multi-RAT capability information to the UTRAN 354 (step 308). The multi-mode / multi-RAT capability information indicates support of E-UTRAN and / or other RATs. For example, the multi-mode / multi-RAT capability information may indicate OFDM support, E-UTRAN support for UTRAN handoff, OFDM radio frequency (RF) capability, OFDM measurement capability, and the like. The support of OFDM may enumerate the supported OFDM channel bandwidths (eg, 1.25 MHz, 2.5 MHz, 5 MHz, 10 MHz, 15 MHz, 20 MHz). The E-UTRAN's support for the UTRAN handoff is preferably a Boolean value indicating such capability of the WTRU.

The OFDM RF capability and OFDM measurement capability represent the WTRU's OFDM RF capability and measurement capability for the UTRAN. OFDM channels may have different bandwidths depending on system configuration, desired bit rate and delay associated with any service. For example, to achieve the highest bit rate allowed (eg 100 Mbps), the E-UTRAN must transmit and receive using the highest allowed bandwidth (eg 20 MHz). The E-UTRAN may run several combinations of these services (different bandwidths for different WTRUs). Therefore, handoff to the E-UTRAN should be triggered based on the WTRU's OFDM RF capabilities. During handoff, when the WTRU performs measurements, the WTRU is preferably tuned and configured to certain channel frequency and specific bandwidth for the measurement. When the WTRU reports measurements for UTRAN, the UTRAN correlates the measurements with the physical attributes of E-UTRAN channels. This ensures that the handoff to the correct target E-UTRAN is supported correctly which supports the desired bit rate and delay requirements.

The multi-mode / multi-RAT capability information may be transmitted via a conventional UTRAN WTRU multi-mode / multi-RAT capability message, a WTRU radio access capability message, a WTRU radio access capability extension message, or any other kind of message. have. Tables 2-4 show example UTRAN WTRU multi-mode / multi-RAT capability messages, WTRU radio access capability messages and WTRU radio access capability extension messages, each containing new IEs (in bold font) according to the present invention. .

Referring again to FIG. 3, the UTRAN 354 receives a WTRU multi-mode / multi-RAT capability message (step 310). Next, the UTRAN 354 sends a measurement capability message to the WTRU 352 (step 312). The measurement capability message defines the parameters required for the measurements. New IEs for E-UTRAN are included in the conventional measurement capability message and measurement capability extension message for E-UTRAN parameters (eg, OFDM measurement parameters for each frequency band). Each IE in the measurement capability message and the measurement capability extension message is a Boolean value indicating whether a downlink or uplink compression mode is required to perform measurements for each frequency band.

Tables 5 and 6 show example UTRAN measurement capability messages and measurement capability extension messages, respectively. The new IE introduced according to the present invention is shown in bold font.

Referring back to FIG. 3, the UTRAN 352 receives a measurement capability message. Next, the WTRU 352 performs measurements on the E-UTRAN signals 315 over the E-UTRAN channels indicated in the measurement capability message and reports the measurement results to the UTRAN 354 (step 314). The UTRAN 354 may initiate a handoff to the E-UTRAN 356 based on the measurement report.

Although the features and elements of the present invention have been described in particular combinations of preferred embodiments, each feature or element may be used alone without the other features and elements of the preferred embodiments, or other features and elements of the present invention. And may be used in various combinations or without the other features and elements of the present invention.

As can be seen from the foregoing, according to the present invention, it is possible to provide a method and system for supporting an E-UTRAN so that the WTRU can use additional E-UTRAN capabilities and services.

Claims (21)

A wireless communication system supporting the advanced universal mobile communication system (UMTS) terrestrial radio access network (E-UTRAN), E-UTRAN; A UTRAN configured to transmit a list of available radio access technologies, including information related to the E-UTRAN in the coverage area of the UTRAN; And A wireless transmit / receive unit (WTRU) supporting both the E-UTRAN and the UTRAN and also configured to receive the list and receive E-UTRAN services based on the list Wireless communication system comprising a. 10. The system of claim 1 wherein the UTRAN is configured to transmit the list over a broadcast control channel (BCCH). 3. The system of claim 2 wherein the UTRAN is configured to include the list in a cell information list message. 10. The system of claim 1 wherein the UTRAN is configured to send the list on a dedicated channel. The system of claim 1 wherein the RAT of the E-UTRAN is Orthogonal Frequency Division Multiplexing (OFDM). 6. The system of claim 5 wherein the E-UTRAN information comprises one or more of OFDM selection and reselection information, a base transceiver identification code (BSIC), and system specific measurement information. 7. The system of claim 6 wherein the system specific measurement information lists one or more of supported frequency, bandwidth, and output power. The system of claim 1 wherein the WTRU is configured to send its multi-mode / multi-RAT capabilities to the UTRAN. 10. The system of claim 8 wherein the multi-mode / multi-RAT capability comprises E-UTRAN capability. 10. The system of claim 9 wherein the E-UTRAN capability comprises orthogonal frequency division multiplexing (OFDM) capability. 11. The method of claim 10, wherein the multi-mode / multi-RAT capability includes one or more of an indication of OFDM support, an indication of support of handoff between the UTRAN and the E-UTRAN, an OFDM radio frequency capability, and an OFDM measurement capability. Wireless communication system. 12. The system of claim 11 wherein the indication of OFDM support enumerates supported frequencies and bandwidths. The radio of claim 8, wherein the multi-mode / multi-RAT capability is transmitted via one or more of a WTRU multi-mode / multi-RAT capability message, a WTRU radio access capability message, and a WTRU radio access capability extension message. Communication system. 10. The system of claim 8 wherein the multi-mode / multi-RAT capability is transmitted during an attach procedure. 10. The system of claim 8 wherein the multi-mode / multi-RAT capability is transmitted on demand by the UTRAN. 10. The apparatus of claim 8, wherein the UTRAN is configured to send a measurement capability message to the WTRU, the measurement capability message including parameters required to perform measurements for an E-UTRAN channel, wherein the WTRU is the measurement capability message. And perform measurement based on and reporting the measurement results to the UTRAN. 18. The system of claim 16 wherein the UTRAN is configured to initiate a handoff to the E-UTRAN based on the measurement results. 18. The system of claim 16 wherein the measurement capability message includes parameters for orthogonal frequency division multiplexing (OFDM) measurements. The system of claim 1 wherein the WTRU is configured to initiate a handoff from the UTRAN to the E-UTRAN based on the list. 20. The system of claim 19 wherein the handoff is triggered by a user of the WTRU. 20. The system of claim 19 wherein the handoff is triggered automatically.

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