Patent Application
20080070562
The above and other aspects, features and advantages of certain exemplary embodiments of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:
Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features and structures.
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the present invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. Also, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
A technique for operating a radio access network having a complex structure in a broadband mobile communication system of the present invention will be described hereinafter. Although an Orthogonal Frequency Division Multiplexing (OFDM) based mobile communication system will be described as an example, the present invention may also be applied to other types of mobile communication systems.
Referring to
The back-bone network 110 provides core functions for operating the broadband mobile communication system. Logically, the back-bone network 110 includes a control network 113 and a data network 115. The control network 113 is provided to control the MS 150 which attempts to access to the network. The data network 115 is provided to control user data of the MS 150.
The 2-tier node 120 is connected to the control network 113 of the back-bone network 110 and performs a necessary function to control the MS 150. That is, the 2-tier node 120 performs various functions such as user authentication, user location information management, capacity negotiation for the MS 150, and call processing. The 2-tier node 120 does not have a wireless communication function and thus the 2-tier node 120 communicates with the MS 150 through the 1-tier node 130. In an exemplary implementation, the 2-tier node 120 may include an Access Control Router (ACR), an Access Service Network_GateWay (ASN_GW), and an Access Core GateWay (ACGW).
The 1-tier node 130 which communicates with the MS 150 is connected to the data network 115 of the back-bone network 110 and performs a function related to user data communication of the MS 150. That is, the 1-tier node 130 performs a function for facilitating data communication, such as, Internet Protocol (IP) address allocation, Connection IDentifier (CID) allocation, error control, and encryption. In an exemplary implementation, the 1-tier node 130 may include a Radio Access Station (RAS), a Base Station (BS) and an Enhanced Node B (ENB). When the back-bone network 110 is an IP-based network, an IP router is provided so that the 1-tier node 130 is directly connected to the back-bone network 110.
The integrated node 140 is a node which combines both the 2-tier node 120 and the 1-tier node 130. The integrated node 140 is connected to the control network 113 and the data network 115 and thus performs functions of both the 2-tier node 120 and the 1-tier node 130. That is, the integrated node 140 is used when the control of the MS and the communication of the user data need to be processed through one node.
Referring to
The controller 201 provides overall control to the 1-tier node. More specifically, the controller 201 controls network access of an MS and data communication through a wireless channel. The network access of the MS is achieved by performing Downlink (DL) and Uplink (UL) channel synchronization and ranging when the MS attempts to access to the network. The data communication through the wireless channel is achieved by controlling power or scheduling wireless resources. More particularly, according to an exemplary implementation of the present invention, the controller 201 controls the MS so that data is transmitted and received through a radio access network having a 1-tier structure and control information is transmitted and received through a radio access network having a 2-tier structure.
The packet classifier 203 determines whether a packet received from the MS is a data packet or a control information packet. If the data packet is received, the packet is transmitted to the back-bone network, and if the control information packet is received, the packet is transmitted to the 2-tier node. The control information packet transmitted to the 2-tier node includes a plurality of pieces of control information other than control information used for the purpose of wireless control (e.g., power control, channel quality, and so forth). The control information packet used for the purpose of wireless control is processed by the 1-tier node.
The packet processor 205 processes a data packet to facilitate communication with the MS. For example, the packet processor 205 compresses a header of the data packet and encrypts the data packet. The error controller 207 performs error control so that the MS can reliably transmit and receive data. For example, an Automatic Repeat reQuest (ARQ) function may be performed.
According to service capacity information of the MS and Quality of Service (QoS) request information, the service manager 209 determines a service policy for the MS and allocates a CID. For example, when the MS requests a broadcast service, the service manager 209 allocates a CID for the broadcast service. The service capacity information and the QoS request information are provided from the 2-tier node. The IP address manager 211 allocates an IP address for data communication to the MS when a call of the MS is established. Further, the IP address manager 211 maintains and manages the IP address.
The backbone communicator 213 communicates with the back-bone network under the control of the controller 201. For example, if the back-bone network is an IP-based network, the backbone communicator 213 has an IP routing function. The 2-tier node communicator 215 communicates with the 2-tier node under the control of the controller 201.
The RF communicator 217 includes an encoder/modulator 219, a resource mapper 221, an OFDM modulator 223, a Digital to Analog Converter (DAC) 225, an RF transmitter 227, an RF receiver 229, an Analog to Digital Converter (ADC) 231, an OFDM demodulator 233, a resource demapper 235 and a demodulator/decoder 237.
The encoder/modulator 219 encodes and modulates data to be transmitted to the MS. The resource mapper 221 maps the data provided from the encoder/modulator 219 to a sub-carrier resource. The OFDM modulator 223 converts a frequency domain signal, which is mapped to a frequency domain resource and is provided from the resource mapper 221, into a time domain signal by performing an Inverse Fast Fourier Transform (IFFT) operation. The DAC 225 converts a digital signal provided from the OFDM modulator 223 into an analog signal. The RF transmitter 227 converts a baseband signal provided from the DAC 225 into an RF signal and transmits the RF signal through an antenna.
The RF receiver 229 converts an RF signal received through the antenna into a baseband signal. The ADC 231 converts an analog signal provided from the RF receiver 229 into a digital signal. The OFDM demodulator 233 converts a time domain signal provided from the ADC 231 into a frequency domain signal by performing a Fast Fourier Transform (FFT) operation. The resource demapper 235 extracts data corresponding to an allocated resource from data which is mapped to a frequency domain and is provided from the OFDM demodulator 233. The demodulator/decoder 237 demodulates and decodes data provided from the resource demapper 235.
In the aforementioned structure, the controller 201 may perform functions of the packet classifier 203, the packet processor 205, the error controller 207, the service manager 209 and the IP address manager 211. Although these components are depicted by separate blocks in
Referring to
The controller 301 provides overall control to the 2-tier node. More particularly, according to an exemplary implementation of the present invention, the controller 301 controls a function for processing control information of an MS.
The user authentication processor 303 evaluates user information when the MS attempts to access to the network and determines whether a user is authorized to use a service. The user location information manager 305 maintains and manages location information of a plurality of MSs existing within a coverage area of the 2-tier node. The call processor 307 sends a call establishment request to an MS or receives the call establishment request from the MS. That is, when the call establishment request is sent to the MS, the call processor 307 recognizes a location of the MS and performs a paging function. In addition, when the call establishment request is received from the MS, the call processor 307 verifies the call generation and performs a function for service connection. The capacity negotiation processor 309 evaluates service capacity information of the MS and QoS request information when a call of the MS is established. That is, the capacity negotiation processor 309 evaluates capacity (e.g., a type of an available service that can be supported by the MS, the number of antennas, and so forth) and a service level of the MS wherein the service level is determined by a contract of a service provider.
The back-bone communicator 311 communicates with the back-bone network under the control of the controller 301. For example, when the back-bone network is an IP-based network, the back-bone communicator 311 may be an IP router. The 1-tier node communicator 313 communicates with the 1-tier node under the control of the controller 301.
In the aforementioned structure, the controller 301 may perform functions of the user authentication processor 303, the user location information manager 305, the call processor 307 and the capacity negotiation processor 309. Although these components are depicted by separate blocks in
As described above, the 1-tier node and the 2-tier node co-exist in the broadband mobile communication system. The 1-tier node and the 2-tier node are independent from each other and perform their own functions. In an exemplary implementation of the present invention, the broadband mobile communication system may include an integrated node in which both the 1-tier node and the 2-tier node are combined. Although control information is processed in a different manner from data in the 1-tier node and the 2-tier node, since the integrated node combines the 1-tier node and the 2-tier node, the mobile communication system of the present invention can operate a radio access network in a more flexible manner.
Referring to
Upon detecting the MS which attempts to access to the network, in step 403, the 1-tier node performs UL and DL synchronization on the MS.
In step 405, the 1-tier node relays communication of control information between a 2-tier node and the MS so that the MS can access the network. That is, all control functions of the MS are performed by the 2-tier node.
In step 407, the 1-tier node determines whether a call establishment request is received from the MS.
Upon receiving the call establishment request, in step 409, the 1-tier node relays control information between the 2-tier node and the MS so that a call of the MS is established. That is, the 1-tier node reports to the 2-tier node the fact that the call establishment request is generated, and relays the control information for the call establishment.
In step 411, the 1-tier node determines whether service capacity information of the MS and QoS request information are received from the 2-tier node.
Upon receiving the service capacity information and the QoS request information, in step 413, the 1-tier node allocates a CID and an IP address to the MS by using the received information.
After allocating the CID and the IP addresses, in step 415 the 1-tier node is directly connected to a back-bone network (e.g., the Internet) and thus a data packet is transmitted to and received from the MS. Specifically, the 1-tier node performs IP routing so that a UL data packet received from the MS is transmitted to the back-bone network and a DL data packet received from the back-bone network is transmitted to the MS.
Referring to
Upon detecting the MS which attempts to access to the network, in step 503, the 2-tier node performs user authentication. To determine whether the MS can access the network, the 2-tier node communicates with a server for managing user authentication through a back-bone network (e.g., the Internet).
In step 505, the 2-tier node determines and registers user location information. In this step, it is determined in which cell the MS is located, and the location of the MS is continuously traced.
In step 507, the 2-tier node determines whether the 1-tier node reports the generation of a call establishment requested by the MS.
In step 509, the 2-tier node performs a service authentication process. By communicating with a server for managing service authentication through the back-bone network, the 2-tier node determines whether the MS is authorized to receive a service.
In step 511, the 2-tier node negotiates a service capacity of the MS. That is, the 2-tier node evaluates service capacity information, for example, a type of service that can be supported by the MS, the number of antennas, and so on. Further, the 2-tier node evaluates QoS request information of the MS.
Upon evaluating the service capacity information and the QoS request information, in step 513, the 2-tier node provides the service capacity information and the QoS request information to the 1-tier node. The reason why the service capacity information and the QoS request information are transmitted to the 1-tier node is that these pieces of information are necessary for data communication through a wireless channel.
In step 515, the 2-tier node transmits and receives control information to and from the MS via the 1-tier node.
In exemplary embodiments of the present invention described with reference to
According to exemplary embodiments of the present invention, in a broadband mobile communication system, a radio access network having a 1-tier structure and a radio access network having a 2-tier structure co-exist so that services are provided through either one of the radio access networks according to information types. Therefore, advantages of the both radio access networks can be obtained. Optionally, functions of the both radio access networks can be provided using the radio access network having the 1-tier structure. Therefore, flexibility of network operation can increase.
While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2006-0089246 | Sep 2006 | KR | national |
