System of simulating mobile communication and method thereof

System and method of simulating mobile communication by means of local area network are provided. After reset of simulation mobile station, the simulated mobile station is initialized for fetching a dynamic IP address from a simulated base station controller. It is determined whether there exists a simulated base station by receiving a broadcasting packet of the simulated base station. If yes, the simulated mobile station requests the simulated base station controller to obtain the dynamic IP address and establish a channel, and the simulated mobile station performs a certification procedure on the simulated base station. If the certification procedure is successful, the simulation mobile station enters into a link state for simulating mobile communication.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of mobile communication and, more particularly, to a system and a method of simulating a mobile communication system.

2. Description of Related Art

Mobile communication has been known as a rapid, spectacular development in recent years. With reference toFIG. 1, there is illustrated a well-known network structure applicable for mobile communication. A cell80in the network for mobile communication comprises a base station200and two mobile stations (e.g., mobile phones, personal digital assistants (PDAs), or notebook computers)210. It is also known that a number of advanced protocols for mobile communication such as General Packet Radio System (GPRS) and third generation (3G)/Wireless Code Division Multiple Access (WCDMA) have been developed recently due to the rapid progress of mobile communication technology. However, associated chipsets have not been developed or are difficult to obtain. Also, a corresponding network for mobile communication has not been established, resulting in an inhibition of complete peer-to-peer verification.

Some simulation programs for simulating mobile communication system have been proposed to solve the aforementioned problems and perform the protocol conformance test of a base station and a mobile station. However, these simulation programs are not able to perform a complete peer-to-peer verification between a base station and a mobile station, a simulation of handoff between the base station and the mobile station, and a simulation of multiple-to-multiple communication because the characteristics of physical layer have not been considered. Therefore, it is desirable to provide novel system and method of simulating mobile communication in order to mitigate and/or obviate the aforementioned problems.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a system and a method of simulating a mobile communication system by means of a local area network.

With this object in view, the present invention provides a simulation method of a mobile communication system. The simulated mobile communication system has a first machine for simulating a base station controller, a second machine for simulating a base station, and multiple third machines, each simulating a mobile station associated with the corresponding base station. The first, second, and third machines are coupled together by a local area network (LAN). Each of the third machines has an upper adaptation layer, a control entity, a service entity, an event generator, a pseudo driver, a network translation program, and a database. The upper adaptation layer is interfaced with an upper layer mobile communication protocol. The control entity is commanded by the upper layer mobile communication protocol for setting communication channels and associated physical layer measurement. The service entity provides physical services to the upper layer mobile communication protocol. The event generator generates simulation events. The method comprises the steps of: (a) after resetting one of the simulated mobile stations, commanding the mobile station to enter into an initialization state for fetching a dynamic Internet Protocol (IP) address from the simulation base station controller; (b) after the simulated mobile station obtains the dynamic IP address, determining whether there exists a simulated base station by receiving a broadcasting packet of the simulated base station; (c) if the simulated base station exists, commanding the simulated mobile station to request the simulated base station controller to obtain a dynamic IP address controlled by the simulated base station and establish an associated channel; (d) commanding the simulated mobile station to perform a certification procedure on the simulated base station via the channel; and (e) if the certification procedure is successful, commanding the simulated mobile station to enter into a link state for simulating mobile communication.

The present invention provides a system of simulating mobile communication, which comprises a first machine for simulating a base station controller, at least a second machine for simulating a base station, and a plurality of third machines each for simulating a mobile station associated with the corresponding base station. The first, second, and third machines are coupled together by a local area network. Each of the third machines comprises an upper layer adaptation layer interfaced with a separate upper layer mobile communication protocol, a control entity commanded by the upper layer mobile communication protocol for setting communication channels and associated entity layer measurement via the upper layer adaptation layer, a service entity for providing physical services to the upper layer mobile communication protocol, an event generator for generating simulation events, a pseudo driver, a network translation, and a database. In response to resetting the simulated mobile station, the simulated mobile station enters into an initialization for fetching a dynamic Internet Protocol (IP) address from the simulated base station controller. In response to obtaining the dynamic IP address, the simulated mobile station determines whether there exists a simulated base station by receiving a broadcasting packet of the simulated base station, and if yes, the simulated mobile station request the simulated base station controller to obtain the dynamic IP address and establish an associated channel. The simulated mobile station performs a certification procedure on the simulated base station via the channel. If the certification procedure is successful, the simulated mobile station enters into a link state for simulating mobile communication.

Other objects, advantages, and novel features of the invention will become more apparent from the detailed description when taken in conjunction with the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference toFIG. 2, there is shown a system of simulating mobile communication in accordance with the present invention. The system comprises a first machine10for simulating a base station controller, two second machines20,30for simulating base stations, and a plurality of third machines40,50,60, and70for simulating mobile stations associated with the base stations. The first, second, and third machines are coupled together by a local area network (LAN). In this embodiment, the LAN is implemented as a well-known Ethernet. As shown, a cell80is comprised of the second machine20and third machines40,50, and another cell90is comprised of the second machine30and third machines60,70.

In the Ethernet, each of the first machine10, second machines20,30, and third machines40,50,60and70has its own Internet Protocol (IP) address for simulating identification (ID) of mobile devices. IP address of each of the first machine10and second machines20,30is fixed and IP addresses of each of the third machines40,50,60and70are dynamically assigned by the first machine10. A plurality of different cells are formed in the Ethernet by a plurality of different sub-networks each corresponding to a base station. An association between a mobile station and a cell formed by base station is determined by a dynamically assigned IP address.

With reference toFIG. 3, a mobile station simulated by any of the third machines40,50,60, and70comprises an upper adaptation layer101, a control entity102, an event generator103, a service entity104, a pseudo driver105, a network translation program106, and a database107. The upper adaptation layer101is interfaced with a separate upper layer mobile communication protocol120. The interfaced upper layer mobile communication protocol120comprises a layer 3 (L3) or Radio Resource Control (RRC)121and a layer 2 (L2) or Media Access Control (MAC)122. Both L3/RRC121and L2/MAC122are associated with Open System Interconnection (OSI) protocol.

The control entity102is commanded by the upper layer mobile communication protocol120for setting communication channels and associated physical layer measurement via the upper adaptation layer101. The service entity104is served to provide services (e.g., channel quality measurement and mapping between transport channel and physical channel) to the upper layer mobile communication protocol120. The event generator103is served to generate simulation events such as event for simulating signal fading or the like so that the upper layer mobile communication protocol120is capable of testing a handoff procedure or simulating propagation delay or propagation error.

The pseudo driver105is served to send the simulation events to the upper adaptation layer101or simulate mobile station driver such as automatic frequency control (AFC) or automatic gain control (AGC). The network translation106comprises a translation layer108interfaced with the pseudo driver105for providing Transport Control Protocol/User Datagram Protocol (TCP/UDP), a network layer109for providing a dynamic IP address assignment mechanism, and a driver layer110for providing a driver to the Ethernet.

An enabled mobile station will retrieve information about base station (e.g., radio frequency (RF) and primary scrambling code of broadcasting channel of the base station before shutdown) from a Subscriber Identity Module (SIM) card at the cell where a previous shutdown was taken place. Such information is sent to a RF component via the L3/RRC121of the mobile station for registration at base station. With reference toFIG. 4, there is shown a flow chart illustrating a process of simulating mobile communication according to the invention. Steps of the process will now be described in detail below. In response to reset of a simulation mobile station, the simulation mobile station enters an initialization so as to fetch a dynamic IP address from the simulation base station controller (step S401).

An enabled mobile station will retrieve information about base station (e.g., RF and primary scrambling code of broadcasting channel of the base station before shutdown) from the database107. Information is sent to the control entity102via L3/RRC121of the upper layer mobile communication protocol120. In detail, in response to a receiving of request (REQ) of L3/RRC121via the upper adaptation layer101, the control entity102sends a confirmation (CNF) signal back to L3/RRC121for acknowledgement and sends the request (REQ) to the service entity104for searching base station.

In response to a receiving of REQ from the control entity102, the service entity104calls the associated pseudo driver105so as to read corresponding sub-network setting from the database107. The pseudo driver105may set the network translation106, including the translation layer108, the network layer109, and the driver layer110based on the sub-network setting for accessing the Ethernet and in turn for obtaining any assigned dynamic IP address from the simulation first machine10(i.e., the base station controller) over the Ethernet.

In response to the obtaining of dynamic IP address, the simulation mobile station determines whether there exists a simulation base station by receiving a broadcasting packet of the simulation base station (step S402). The simulation base station always broadcasts system information such as RF and primary scrambling code via a broadcasting channel. Thus, in response to the obtaining of dynamic IP address by the simulation mobile station, the broadcasting packet is received by the driver layer110and the network layer109. The translation layer108then filters and obtains the system information by translation. The system information is in turn sent to the pseudo driver105which may send indication (IND) to the upper layer adaptation layer101for an appropriate protocol data unit (PDU) format translation prior to sending to the L2/MAC122of the upper layer protocol120for mobile communication. Finally, it is sent to the L3/RRC121of the upper layer mobile communication protocol120for determining whether there exists a corresponding simulation base station.

The process goes to step S403if the determination in step S402is positive. Otherwise, the process jumps to step S407. In step S403, the L3/RRC121of the upper layer mobile communication protocol120will issue a request REQ to the control entity102for setting other channels for registration. The control entity102then sends the REQ to the service entity104. Also, the pseudo driver105sets the translation layer108for filtering out all packets not belonging to the selected simulation base station. At the same time, the network layer109requests the simulation base station controller10again to permit it to obtain a dynamic IP address in the sub-network of the simulation base station and establishes an associated channel (Ethernet port) for simulating a cell formed by the simulation base station. Then, the simulation mobile station may perform a registration certification procedure on the simulation base station via the channel.

In step S404, it is determined whether the registration certification procedure is successful. If yes, the process goes to step S405. Otherwise, the process jumps to step S409.

In step S405, the simulation mobile station enters into a link state for simulating mobile communication. The event generator103generates a received signal strength indicator (RSSI) based on a random procedure. The RSSI is in turn sent to the upper layer mobile communication protocol120by the pseudo driver105. Furthermore, the upper layer mobile communication protocol120determines whether RSSI is larger than a predetermined value. If yes, the process goes to step S406. Otherwise, the process jumps to step S407. In step S406, a handoff is not required. Further, packet receiving and sending are performed for simulating mobile communication. The process then loops back to step S405.

The step S407is performed when the determination in step S402or S405is negative. The upper layer mobile communication protocol120will issue a search command to the control entity102again for re-searching a simulation base station. Likewise, the control entity102will send a command to the service entity104. In response to the receiving, the service entity104calls the pseudo driver105to re-set the translation layer108for receiving system information of different simulation base stations on the broadcasting channel to the pseudo driver105. Hence, the upper layer mobile communication protocol120may determine whether there exists a simulation base station based on the system information.

In step S408, it is determined whether there exists a simulation base station. If yes, the process loops back to step S403. Otherwise, the process jumps to step S410.

In step S410, the simulation mobile station performs a communication error procedure for suspending the service entity104, the event generator103, the pseudo driver105, and the network translation106. Only the control entity102is able to receive physical layer (L1) system commands (e.g., reset and cell measurement) from the L3/RRC121of the upper layer mobile communication protocol120. The process is thus terminated.

In step S404, if it determines that the registration certification procedure is fail, the process jumps to step S409. In step S409, it is determined whether the number of certification failure is larger than a maximum allowable value. If yes, the process loops back to step S407. Otherwise, the process loops back to step S403.

From the aforementioned description, the simulation technology for wireless communication of present invention can solve the problem in that associated chipsets have not been developed or are difficult to obtain. Also, it overcomes the problem in inhibiting a complete peer-to-peer verification due to that the corresponding infrastructure for mobile communication has not been established. Because the event generator103is provided for simulating the characteristic of the physical layer in present invention, it can perform a simulation of handoff between the base station and the mobile station, and further a simulation of multiple-to-multiple communication.