CN101123760B - Realization Method of Traditional Group Call Triangulation Positioning in Digital Trunking Communication System - Google Patents

Abstract

The invention discloses a method for realizing traditional group call triangulation positioning in a digital trunking communication system. Aiming at the problem that the correct EPN cannot be obtained in the triangulation positioning service under the condition of front and reverse channel sharing of the existing PTT traditional group call trunking system, the present invention The invention comprises the following steps: (1) the base station receives the PTT traditional group call service message from the terminal, and the bottom layer of the base station reports the PN and EPN of the terminal collected by the chip to the upper layer application of the base station; (2) the upper layer application of the base station according to the described The PN and the EPN calculate the target one-way delay or service one-way delay of the terminal, and report it to the network side positioning center to calculate the position of the terminal. The invention solves the problem of inaccurate acquisition of EPN when the forward and reverse channels are shared in the traditional group call digital trunking system, realizes accurate positioning of the mobile terminal, and is suitable for the existing trunking system.

Description

Realization Method of Traditional Group Call Triangulation Positioning in Digital Trunking Communication System

technical field

The invention relates to the field of mobile communication, adding positioning technology to a trunking-based communication system, and realizing a specific user positioning method in a traditional group call digital trunking communication system.

Background technique

The digital trunking communication system is a system that can provide mobile dispatching services to professional or public users, and represents the development direction of private mobile communication networks. The traditional group call trunking system has the characteristics of channel sharing and unlimited capacity of a single carrier. Among the current positioning methods, GPS-One and GPS positioning technology need the support of a special terminal chip, which requires the replacement of a new type of terminal.

The processing flow of triangulation positioning is: use the positioning center (MPC: Mobile Position Center) to initiate a measurement request report for the position of a certain terminal to the base station, the base station sends a wireless position measurement request to the terminal in the call, and the terminal receives the measurement request Report the pilots of its own active set and candidate set to the base station. If the terminal is under the coverage of multiple base stations, the specific geographical location of the terminal can be calculated through the information reported by the terminal to meet the requirements of locating the terminal.

EPN (Earliest PN offset) is an important parameter used in the triangulation positioning system. Through EPN, the target one-way delay and service one-way delay of the terminal to a certain base station can be calculated, and reported to the network side to calculate the position of the terminal. In other existing services, one channel corresponds to one terminal, and the EPN is obtained through periodic reporting by the channel board. The cycle is very short, and the EPN may fluctuate, but not greatly.

The traditional group call service is an extension of the PTT (Push To Talk) group call service, which is used to solve the limitation of the air capacity of the original group call service and realize the communication between the initiator of the traditional group call and all users in the group. The main features of the traditional group call service function: single-carrier sector unlimited capacity and forward channel sharing.

Unlimited capacity for a single-carrier sector, unlimited capacity for a single group call under a single-carrier sector, unlimited capacity for a single group of users in each sector, and limited resources, especially wireless resources, to support emergency situations, Functions such as command and dispatch under the condition of user concentration; the number of users in the same sector has no effect on the access time.

Forward channel sharing, in order to achieve the purpose of group users sharing the forward channel, the shared traffic channel has the same Walsh code, frame offset and long code mask, and the content of the business frame at the same time is the same, in the signaling process You must increase the passing of the corresponding parameters. In the forward link, a forward voice channel is shared in the group; in the group, users under the same bearer share a forward signaling channel: the channel resources of the cell are directly allocated through the broadcast channel assignment message, and the terminal directly establishes the corresponding channel , without signaling handshake and business negotiation with the base station, so as to improve the access and switching speed of the terminal; reverse link, only one user can speak at the same time on the reverse link, that is, the user exclusively occupies the reverse voice channel; group Within the same carrier, users share a reverse signaling channel, and the reverse signaling transmission adopts a random sending strategy.

In traditional PTT group calls, EPN is also obtained by reporting on the channel board. However, because the front and back channels are shared, multiple terminals share the same channel, and terminals and channels are no longer in one-to-one correspondence. If the traditional method of obtaining EPN is adopted The method is to rely on the channel board to report periodically, then the EPN reported by the channel board at a certain moment may belong to terminal A, but at another time the EPN reported by the channel board may belong to terminal B, because the geographical location of terminal A and terminal B may be far apart , In this way, the EPN will change greatly, and the correct EPN cannot be obtained. Inaccurate EPN acquisition directly affects the accuracy of the final calculated position.

Contents of the invention

Aiming at the defects and deficiencies in the prior art, the present invention provides a method for realizing the triangulation positioning of the traditional group call triangulation of the trunking system in which the correct EPN is obtained in the triangulation positioning service under the condition that the reverse channel is shared before the PTT traditional group call trunking system .

In order to achieve the above-mentioned purpose of the invention, the realization method of the traditional group call triangulation positioning of the digital trunking communication system of the present invention is characterized in that: comprising the following steps:

(1) The base station receives the PTT traditional group call service message from the terminal, and the bottom layer of the base station reports the PN and EPN of the terminal to the upper layer application of the base station;

(2) The upper layer application of the base station calculates the target one-way delay or service one-way delay of the terminal according to the PN and EPN, reports it to the network side positioning center, and calculates the position of the terminal.

In the implementation method of traditional group call triangulation in the above-mentioned digital trunking communication system, the PTT traditional group call service message described in step (1) is to listen to the power intensity measurement message sent by the user, or the message sent by the user.

In the implementation method of the traditional group call triangulation positioning of the above-mentioned digital trunking communication system, the step (2) includes the following steps:

(21) The upper layer application of the base station judges whether the EPN corresponding to the PN reported by the bottom layer is a reference PN by the PN reported by the bottom layer, if yes, step (22) is executed; if not, step (23) is executed;

(22) The upper layer application of the base station calculates the service one-way delay of the terminal, and reports it to the network side positioning center to calculate the position of the terminal, and the step ends;

(23) The upper layer application of the base station calculates the EPN of the reference PN according to the existing reference PN and the PN and EPN reported by the bottom layer, and then calculates the target one-way delay of the terminal, and reports it to the network side positioning center to calculate the EPN of the reference PN. The location of the terminal is specified, and the step ends.

In the implementation method of the traditional group call triangulation positioning of the above-mentioned digital trunking communication system, the step (21) is specifically: the upper layer application of the base station compares the PN value reported by the bottom layer with the reference PN value, and if the two are equal, the reported by the bottom layer is the same as the reference PN value. If the EPN corresponding to the PN is the EPN of the reference PN, step (22) is performed; otherwise, step (23) is performed.

The invention solves the problem of inaccurate acquisition of EPN when the forward and reverse channels are shared in the traditional group call digital trunking system, and realizes accurate positioning of the mobile terminal so as to carry out various trunking positioning services.

Description of drawings

Fig. 1 is the flow chart of PTT scheduling server to terminal;

Fig. 2 is the flow chart of terminal to PTT scheduling server;

Fig. 3 is the processing flowchart of base station bottom layer;

Fig. 4 is a processing flow chart of the upper layer application of the base station.

Detailed ways

Below in conjunction with accompanying drawing, the present invention will be described in further detail:

The technical solution of the present invention is: after the bottom layer of the base station receives the air interface message sent by the terminal, it judges that if it is listening to the user and it is a PSMM (power intensity measurement) message, the PN and EPN collected by the chip are added to the message and reported to the Upper-layer application; if it is a user, add the PN and EPN collected by the chip to the message and report to the upper-layer application. After receiving the measurement response message, the upper-layer application judges that if the EPN is the reference PN, it will directly report the service one-way delay. If not, it must calculate the EPN of the reference PN based on the EPN collected by the chip, and then calculate the target one-way delay.

Concrete steps of the present invention may include:

Step 1: If the bottom layer judges that it is listening to the user and it is a PSMM message, add the PN and EPN collected by the chip to the message and report it to the upper layer application, and enter step 3; otherwise, transfer to step 2 for processing;

Step 2: If the bottom layer judges that it is a user, add the PN and EPN collected by the chip to the message and report to the upper layer application;

Step 3: After the upper-layer application receives the message reported by the lower layer, it judges whether the EPN reported by the lower layer refers to the PN. If it is, use the existing technology to calculate the service one-way delay, and report it to the cluster dispatcher server through the cluster dispatcher client , for the network side positioning center to calculate the position of the terminal; if not, go to step 4;

Step 4: The upper-layer application judges that the EPN reported by the lower layer is not the reference PN. According to the EPN, PN and reference PN reported by the lower layer, the EPN' of the reference PN can be calculated, and the target one-way delay can be calculated. The cluster dispatcher server reports. It is used for the positioning center on the network side to calculate the position of the terminal.

Figure 1 and Figure 2 illustrate the process of triangulation positioning, and Figure 3 and Figure 4 illustrate the processing process of obtaining EPN and calculating related parameters inside the base station.

Figure 1 includes the following steps:

101. The base station receives the message sent by the cluster dispatcher server through the cluster dispatcher client;

102. The base station detects whether the message is a wireless location measurement request message according to the message type. If it is not a wireless location measurement request message, go to step 103; if it is a wireless location measurement request message, go to step 104;

103. The base station processes the corresponding message according to its message type;

104. The base station detects the legitimacy of the message; if there is an error in the message, go to step 105; otherwise go to step 106;

105. The base station returns a message to the cluster dispatcher server through the cluster dispatcher client, and the message carries a cause value;

106. The message is normal, and the base station sends the wireless position measurement request message to the mobile phone through the air interface.

Figure 2 includes the following steps:

201. The base station receives the message sent by the terminal through the air interface;

202. The base station judges whether it is a PTT traditional group call and is a positioning message. If yes, go to step 203; otherwise, go to step 207;

203. The base station judges whether the message is a wireless measurement response message; if not, go to step 204; otherwise, go to step 205;

204. The base station processes the corresponding message according to the message type;

205. The base station calculates the target one-way delay, and proceeds to step 206;

206. The base station constructs a wireless location measurement response message, and sends it to the PTT scheduling server via the PTT scheduling client, for the network side to calculate the location of the mobile phone;

207. End.

Figure 3 includes the following steps:

301. The bottom layer receives a message from the terminal through the air interface;

302. The bottom layer judges whether it is a PTT traditional group call service, if yes, go to step 303; if not, go to step 307;

303. The bottom layer judges whether it is listening to the user and is a PSMM message. If yes, go to step 304; if not, go to step 305;

304. The bottom layer writes the EPN and PN into the PSMM message to report to the upper layer application and turn to step 307;

305. The bottom layer judges that it is the user message, if yes, go to step 306; otherwise go to step 307;

306. The bottom layer fills in the EPN and PN in the first frame of the segment signaling to report to the upper layer application and go to step 307;

307. The underlying processing ends.

Figure 4 includes the following steps:

401. The upper layer application receives the message reported by the lower layer;

402. The upper-layer application judges whether it is a traditional group call and is a positioning message, if yes, go to step 403; otherwise, go to step 408;

403. The upper layer application determines whether the EPN corresponding to the PN reported by the bottom layer is the EPN of the reference PN by judging whether the PN reported by the bottom layer is equal to the RefPN (reference PN). If yes, go to step 404; otherwise, go to step 405;

404. The upper-layer application calculates the service one-way delay and turns to step 407;

405. The upper layer application calculates the EPN of the reference pilot according to the collected EPN and proceeds to step 406;

406. The upper layer application calculates the target one-way delay and goes to step 407;

407. The upper layer application constructs a wireless measurement location response message and sends it to the PTT scheduling server through the PTT scheduling client, so that the network side can calculate the location of the terminal;

408. End.

Claims (3)

1. a kind of realization method of traditional group call triangulation positioning of digital trunking communication system, it is characterized in that: comprise the following steps: (1) The base station receives the PTT traditional group call service message from the terminal, and the bottom layer of the base station reports the pseudo random noise PN and the earliest pseudo random noise compensation EPN of the terminal collected by the chip to the upper layer application of the base station; (2) The upper layer application of the base station judges whether the EPN corresponding to the PN is the EPN of the reference PN through the PN reported by the bottom layer. The location of the terminal, otherwise the upper layer application of the base station calculates the EPN of the reference PN based on the existing reference PN and the PN and EPN reported by the bottom layer, and then calculates the target one-way delay of the terminal, and reports it to the network side positioning center to calculate the location of the terminal. 2. the realization method of traditional group call triangulation of digital trunking communication system according to claim 1 is characterized in that: the PTT traditional group call business message described in the step (1) is to listen to the power intensity measurement message that user sends or Say a message sent by a user. 3. The method for realizing traditional group call triangulation in digital trunking communication system according to claim 1 or 2, wherein the base station upper layer application judges whether the EPN corresponding to the PN is the EPN of the reference PN through the PN reported by the bottom layer Specifically: the upper layer application of the base station compares the PN value reported by the bottom layer with the reference PN value, and if the two are equal, the EPN corresponding to the PN reported by the bottom layer is the EPN of the reference PN.

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