KR100241789B1 - Method for processing a call from cordless fixed part to cordless portable part in radio communication system - Google Patents

Abstract

The present invention discloses a method for processing a call between a base station and a radio terminal period in a wireless communication system. The present invention adds a called cell area to an existing cell area, and compares the RSSI of the signal received from the CPP with the RSSI reference value during the call processing operation to determine whether the CPP exists in its called cell area. The CFP ensures that a call service between CFPs is performed only when the RSSI of the signal received from the CPP is equal to or greater than the RSSI reference value, that is, when the CFP exists in the called cell area of the CPP. The present invention can eliminate the phenomenon that the CPP responds to the call, not the cell area of the CFP, and thus subscribers can receive the call service only from the CFP of the cell area where they are located.

Description

Call processing method of wireless communication system

The present invention relates to a call processing method of a wireless communication system, and more particularly, to a method for processing a call from a base station to a wireless terminal.

Typically, a wireless communication system such as a 2nd generation cordless telephone (CT-2) is configured as shown in FIG. Referring to FIG. 1, the base station (CFP) cordless fixed parts (CFPs) 111 to 113 are connected to a public switched telephone network (PSTN) through a base station management apparatus 100 by wire. Cordless portable parts (CPPs) 11 to 17 are wirelessly connected to each base station. Accordingly, functions such as call service, call service, handover service, and location tracking between each base station and wireless terminal are performed.

In FIG. 1, one or more base stations form a cell in one region, where each cell is structured as shown in FIG. This structure shows the structure of a cell according to the CT-2 CAI (Common Air I) standard. According to the standard, each cell is a NEAR CELL C1, a FAR CELL C2, a HANDOVER CELL. It is structured as C3 and a RELINK CELL. Note that the cells according to the ETS standard are only cells related to call, not cells related to call.

On the other hand, in the CT-2 cell design, the basic direction is to design the cell so that the communication service area can be included while overlapping the cells. If we try to include all these areas, we have no choice but to adjust the cell to be smaller than the actual area of radio waves. In this cell configuration, the CFP unilaterally sends a call signal (ID_OK, UI message) according to the conventional method as shown in FIG. 3 without configuring a call cell (area where the CCP can receive a call signal and ring). If there is no CPP in the cell area to which the CFP sending the called signal belongs, there is a problem that the ring rings.

That is, referring to FIG. 3, after receiving an instruction to transmit a call message to a specific CPP from the base station management apparatus 100 of FIG. 1, the CFP transmits the call message to the corresponding CPP. When the corresponding CPP detects the call message, an ID_OK message is transmitted to the CFP in response to the call. From this time, a ring is generated in the CPP. This ring can be generated because CPP has already received the UI (SIG_ON) message, which is a message related to ring generation, from the CFP in the previous step. As described above, the ring generation occurs in the CPP even when the CPP does not exist in the cell region to which the CFP belongs. When such a ring occurs, subscribers will typically press a button for a call on CPP in response to the generated ring. However, even when the subscriber presses the button for the call, the call operation is not normally performed because the CPP does not exist in the cell area to which the CFP belongs. More specifically, the subscriber will only hear the disconnection of the call even when the call button is pressed.

Accordingly, an object of the present invention is to provide a method for processing a ring to be generated only when a CPP exists in a cell area to which a CFP belongs during a call processing operation in a wireless communication system.

Another object of the present invention is to provide a method for normalizing a call processing between a CFP and a CPP in a wireless communication system.

In order to achieve the above object, the present invention adds a called cell area to an existing cell area, and compares the RSSI of the signal received from the CPP with the RSSI reference value when the CFP is called. Determine whether or not. The CFP ensures that a call service between CFPs is performed only when the RSSI of the signal received from the CPP is equal to or greater than the RSSI reference value, that is, when the CFP exists in the called cell area of the CPP. The present invention can eliminate the phenomenon that the CPP responds to the call, not the cell area of the CFP, and thus subscribers can receive the call service only from the CFP of the cell area where they are located.

1 is a view showing the configuration of a general CT-2 system.

FIG. 2 shows a cell structure of the CT-2 system shown in FIG.

3 is a view showing a flow of a call processing process according to the prior art.

4 is a view showing a cell structure of a CT-2 system according to the present invention;

5 is a view showing the flow of the call processing process according to the present invention.

DETAILED DESCRIPTION A detailed description of preferred embodiments of the present invention will now be described with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. In addition, the terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of the user or chip designer, and the definitions should be made based on the contents throughout the present specification.

4 is a view showing a cell structure according to the present invention, like the cell structure according to the prior art illustrated in FIG. 3, a near cell C1, a far cell C2, and a handover cell C3. In addition to the structure including the relink cell (RELINK CELL), the structure further includes a called cell C4. Each of these cell areas is constructed by setting a reference value of Received Signal Strength Indicator (RSSI), and the reference value of RSSI for each cell may be set through a base station management apparatus or a maintenance computer of the base station itself. . Although the called cell is shown at the outermost part in the figure, the cell area may be changed according to the environment of the cell.

The operation of the call processing according to the present invention is achieved by structuring the cell area as shown in FIG. 4 and causing the base station (CFP) and the radio terminal (CPP) to be processed as shown in FIG.

Now, when the base station management apparatus 100 of FIG. 1 instructs the called CPP to transmit an incoming message, the CFP receives this command in step 51 of FIG. 5, and then the unique ID of the called CPP in step 53. ID_OK message including PID, and UI (SIG_OFF) message related to ring occurrence are transmitted to CPP. The operation of transmitting the call message is continuously performed for 5 seconds by the CFP driving the 5 second timer in step 52. At this time, it should be noted that the UI message includes a SIG_OFF message indicating that ring generation is turned off unlike the prior art.

If the called CPP detects that the called CPP has received the call message from the CFP in step 54 during the transmission operation of the received message, the response message indicating that the CPP has received the call message in response to the radio link is established. ID_OK (PID) is sent to the CFP. In this case, a ring is generated according to the prior art, but according to the present invention, since the ring generation off information SIG_OFF is included in the call message transmitted in step 53, the ring is not generated.

The CFP sends an ID_OK (PID) message to the CPP in response to receiving the ID_OK (PID) message from the CPP. In step 55, the CFP measures the RSSI of the CPP in the set radio link state after terminating the previously operated 5 second timer, and in step 56, the RSSI of the measured CPP and the preset received field strength reference value (called cell RSSI). Compare with In step 56, when the RSSI of the CPP is smaller than the RSSI reference value, the CFP considers the called CPP to be outside the called cell area and terminates the call procedure.

However, if it is determined in step 56 that the RSSI of the CPP is greater than or equal to the RSSI reference value, the CFP considers the called CPP to be in the called cell and performs an operation accordingly. That is, the CFP converts a UI (SIG_OFF) message including ring generation off information into a UI (SIG_ON) message including ring generation on information and transmits the CPP to the call service. The CFP also starts a 20 second timer in step 57, waiting for the CPP to respond to the call. In response to receiving the UI (SIG_ON) message, the CPP transmits an ID_OK (PID) message, which is a response message, to the CFP, and generates a ring in step 58 to inform the subscriber that the call has been received.

If the subscriber of the CPP presses a button for a call during this ring generation operation, the CPP determines this in step 59 and transmits a LINK_REQUEST message for link request to the CFP. In response to receiving the LINK_REQUEST message, the CFP transmits a LINK_GRANT message indicating link approval to the CPP, and terminates the operation of the 20 second timer that was previously driven in step 60. After performing the above operation, the CFP and the CPP perform a call service according to the CT-2 CAI standard.

As described above, the present invention has the advantage of eliminating the problem of the call service out of the cell area when the cell is configured by adding the call cell concept to the existing CT-2 cell. That is, the present invention can eliminate the phenomenon that the CPP, not the cell area of the CFP, responds to an incoming call. Accordingly, subscribers have an advantage of receiving a call service only from the CFP of the cell area in which they are located.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by the equivalents of the claims.

Claims (2)

In the call processing method of a wireless communication system comprising a base station connected by wire to a base station management device and a wireless terminal wirelessly connected to the base station, A first step of the base station radiating a first call message including ring generation off information to the air when a command of a call message transmission is received from the base station management apparatus; A second step of transmitting, to the base station, a response message indicating that the wireless terminal receiving the first call message has received the first call message; A third step of the base station receiving the response message and determining whether the electric field strength of the received response message is equal to or greater than a preset reference value; A fourth step of transmitting, by the base station, a second call message including ring generation temperature information to the wireless terminal when the electric field strength of the response message is equal to or greater than the reference value; A fifth process of generating, by the wireless terminal, the ring by receiving the second call message; A sixth step of transmitting, by the wireless terminal, a link request message to the base station when a button for a call is input from a subscriber in response to the ring being generated; And a seventh step of the base station transmitting a link approval message to the wireless terminal in response to the link request message and performing a call processing to the wireless terminal. The method of claim 1, further comprising: an eighth step of terminating the call processing if the base station has a smaller electric field strength of the response message.

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