KR100847521B1 - The method of broadcast sevice data transmission for high data transmission system - Google Patents

Abstract

The present invention relates to a broadcast service data transmission method of a high speed data transmission system for providing a broadcast service in which a plurality of user terminals can share data such as a broadcast service in a CDMA-2000 1xEV-DO system.

The present invention provides a process of transmitting a MAC ID, an offset, period, DRC value of a transmission structure to a user terminal as a message when the user terminal requests a broadcast service from the base station by a message; In a call setup process between base stations to all user terminals, the base station assigns a common MAC ID to which the broadcast data is transmitted to the user terminal, and broadcast data by a scheduler for performing a broadcast service at the base station. Is transmitted to the user terminal.

Broadcasting,

Description

Broadcast service data transmission method of high-speed data transmission system {The method of broadcast sevice data transmission for high data transmission system}

1 is a diagram illustrating data transmission between a user terminal and a base station.

2 is a diagram illustrating one-to-one data transmission between a user terminal and a base station.

3 is a diagram illustrating data transmission when a broadcast service request of the present invention is performed.

4 is a diagram showing the allocation of a MIC ID for transmitting broadcast data of the present invention.

5 illustrates transmission of broadcast data of the present invention.

6 is a diagram illustrating a transmission period of broadcast data of the present invention.

7 is a flowchart of a scheduler for performing the broadcast service of the present invention.

8 is a diagram for calculating the number of transmittable slots of the present invention.

The present invention relates to a data transmission method for supporting a broadcast service in a high speed data transmission system. In particular, the present invention relates to high speed data for providing a service in which multiple user terminals can share data, such as a broadcast service. The present invention relates to a broadcast service data transmission method of a transmission system.

CDMA-2000 1xEV-DO system is 1: 1 data service and user terminal can receive packet data up to 2.4Mbps. The user terminal determines the channel status of the forward link in each slot and requests a data rate that matches the channel status through the data rate control (DRC) channel. Send the data.

The base station transmits data to the user terminal using a time division method. That is, one forward channel is divided into slot units, and a user terminal is selected by a scheduling algorithm in every slot, and data is transmitted according to a required data rate of the selected user terminal. In this case, as shown in FIG. 1, the MAC (Medium Access Control) ID is transmitted on the transmitted data, which is information necessary for determining whether the user terminal is own data.

Since the CDMA-2000 1xEV-DO system transmits data to the user terminal by dividing the forward channel into time divisions when the base station sends traffic data, the CDMA-2000 1xEV-DO system cannot send the same data to multiple user terminals at a specific time. . As shown in FIG. 2, since the base station sends data to the MAC ID assigned to a specific user terminal, the other user terminal does not receive data that is not determined as its MAC ID.

This is difficult to provide a service that allows multiple user terminals to share data, such as broadcast.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and is to provide a broadcast service in a high speed data transmission system, and more particularly, to provide a broadcast service data transmission method in a CDMA-20001xEV-DO system.

When the broadcast data service request is received, the present invention includes transmitting a common MAC ID transmitted to the broadcast packet data and transmission structure information of the broadcast packet data to the user terminal. The call setup process between the base stations and the transmission structure information of the broadcast packet data are determined by the broadcast service data rate, the transmission period of the data, the number of transmission slots and the transmission offset of the packet data, and the common MAC ID and the broadcast And receiving the broadcast packet data using the transport structure information of the packet data.

In the present invention, when providing a broadcast service, the base station allocates a MAC ID to which broadcast data is transmitted, and transmits the service by requesting data rate of the broadcast, the number of transmission slots, and the transmission offset value of the broadcast packet. Determining a data packet structure and transmitting it to the terminal of the user terminal, and transmitting the broadcast data to the user terminal by the scheduler for performing a broadcast service at the base station.

The scheduler for performing the broadcast service transmits a synchronous packet when the sync packet is transmitted, or calculates the number of slots that can be transmitted, and when the broadcast packet is transmitted, when there is broadcast transmission data. If there is Async. Transmission data when the broadcast data is not transmitted and there is no broadcast transmission data or there is no broadcast transmission data, if the slot of the asynchronous packet is less than or equal to the number of slots that can be transmitted, If there is no asynchronous transmission data or if the slot of the asynchronous packet is larger than the number of slots that can be transmitted, a scheduling algorithm is performed to select a packet smaller than the number of slots that can be transmitted and to transmit a traffic packet.

Hereinafter, a broadcast service data transmission method of a CDMA-2000 1xEV-DO system, which is an embodiment of a high speed data transmission system according to the present invention, will be described with reference to the accompanying drawings.

According to the present invention, when a user terminal transmits a broadcast service request message to a base station in order to receive a broadcast service, as shown in FIG. 3, the base station receiving the message receives an offset of a MAC ID and a transmission structure for receiving broadcast data. Sends message, cycle, DRC value to user terminal as message.

In this case, the DRC value is a 4-bit message used to distinguish the data rate set used in the table indicating the transmission structure. In this case, the data rate is used as well as the coding rate. , Modulation scheme, and the like.

In addition, another method for providing the above broadcast service includes a MAC ID to be transmitted in order to receive broadcast data, an offset, a period of a broadcast transmission structure, and the like in a call setup process between a user terminal and a base station. There is also a method of transmitting a DRC value to a user terminal as a message and the user terminal receiving a broadcast service through the terminal interface.

Here, the base station receives the broadcast data through the MAC ID assigned from the base station to the user terminal receiving the broadcast service. In this case, as shown in FIG. 4, the base station allocates a common MAC ID to all user terminals so that all user terminals receive data at the same time. The transmission structure of broadcast data transmitted as described above is as follows.

For example, in the CDMA-20001xEV-DO system, a broadcast data transmission structure refers to a channel structure in which a traffic channel is time-divided and transmitted through resources allocated for dual broadcast.

The structure of transmitting data from the base station to the user terminal is determined by the DRC value transmitted by the user terminal to the base station by determining the forward link and channel conditions. That is, the base station cannot send the data according to the information transmitted from the user terminal without determining the data rate by itself. However, since all user terminals receive a common data rate when transmitting broadcast data, the user base station decodes the data according to the transmission structure of the broadcast data without decoding the data with the DRC value transmitted to the base station through the reverse channel. do.

In order to decode the data, the user terminal needs to know the transmission structure of the broadcast data, which can be seen by exchanging a message in the process of having the call setup with the base station.

The transmission structure of broadcast data is determined by the required data rate of the broadcast service, the period of broadcast data, the number of transmission slots, and the transmission offset value of the broadcast packet data.

Broadcast data rate = R (bps)

Data period = P (slots)

Bits (Payload) to be sent during the transmission cycle = ((R * 2) / 75) * (P / 16)

The transmission data packet structure is determined by the payload size and the number of transmission slots. In this case, when the number of transmission slots is one or more, early termination is not performed until the base station receives an acknowledgment signal (ACK) from all user terminals receiving the broadcast service.

The transmission structure determined by the above process is transmitted at the slot position T that satisfies the following equation.

Broadcast transmission slot location = broadcast offset (BC_offset)

Data period = P (slots)

T% P = BC_offset                     

For example,

R = 76.8 Kbps

P = 16 slots

bits = ((76800 * 2) / 75) * (16/16) = 2048

1.2048-Payload 1-slot 1.2288 Mbps

2.2048-Payload 2-slot 614.4 Kbps

3.2048-Payload 3-slot 307.2 Kbps

The data rate is determined according to the number of transmission slots among the above three.

As such, when the data rate is determined, broadcast data is transmitted by a scheduler for performing a broadcast service.

Here, the scheduler has the following considerations when operating.

1) The broadcast packet data is not transmitted to the transmission position of the sync packet in the control signal.

2) When an asynchronous packet occurs in the control signal, broadcast data is transmitted first.

3) When general traffic packet data occurs, broadcast packet data is given priority.

4) Do not send asynchronous message or general traffic packet data by knowing where to send broadcast packet data.

Hereinafter, the operation of the scheduler for performing the broadcast service of the present invention will be described with reference to FIG.

The scheduler selects a sync packet, an async packet, a traffic packet, and a broadcast data packet at the present time. When selecting a traffic data packet, the user terminal is selected by a scheduler algorithm. First, it is determined whether the synchronization packet is transmitted (step 10). The transmission position of the packet is determined by the upper message for each sector, and the synchronization packet is unconditionally transmitted because the position of the synchronization packet has the highest transmission priority. This is because the broadcast packet control signal is not transmitted at the same position as the sync packet. If the sync packet is the transmission location in step 10, the sync packet is transmitted and terminated (step 20).

If it is not the transmission position of the sync packet in step 10, the number of transmittable slots (TxSlots) is calculated and the process moves to the next step (step 30).

In the CDMA-2000 1xEV-DO system, a slot of a packet is transmitted by four slot interlacing, and when the packet is transmitted at the current slot position, the maximum number of possible slots of the packet is calculated. Here, the maximum possible number means the maximum slot value where the transmission positions of the synchronization packet and the broadcast packet are predetermined so that the transmission positions do not overlap with each other.

After calculating the maximum number of slots that can be transmitted, it is determined whether a broadcast packet is transmitted (step 40). This is to preferentially view broadcast packets when an asynchronous packet occurs as a control signal, and not to send an asynchronous packet or a general traffic data packet by determining the transmission position of the broadcast packet.                     

If it is the broadcast packet transmission position in step 40, it is determined whether there is a broadcast transmission data packet, and if there is a broadcast transmission data packet, it moves to step 60; if there is no broadcast transmission packet data, it moves to step 70 (step 50). . To send broadcast data packets first when a regular traffic packet occurs.

If there is a broadcast transmission packet in step 50, the broadcast data is transmitted and ends (step 60).

In step 40, if there is no broadcast packet transmission position, or if there is no broadcast transmission packet in step 50, it is determined whether there is an asynchronous transmission packet. (Step 70).

If there is an asynchronous transmission packet in step 70, the slot of the asynchronous packet is compared with the number of slots (TxSlots) that can be transmitted and the maximum number of slots (TxSlots) that can be transmitted. If the number of slots of the asynchronous packet is large, the process moves to step 100 (step 80).

In step 80, if the number of slots of the asynchronous packet is less than or equal to the number of slots TxSlots of the packet can be transmitted and ends (step 90).

If there is no asynchronous packet in step 70 or the slot number of the asynchronous packet is greater than the number of slots (TxSlots) capable of transmitting packets in step 80, a scheduling algorithm is performed to select a packet smaller than the number of slots (TxSlots) that can be transmitted. Send and exit (step 100).

As described above, the present invention has an effect of providing a broadcast service by effectively allocating a channel in a high speed data transmission system.

Claims (6)

Receiving a broadcast data service request; And The transmission MAC information of the broadcast packet data determined by the common MAC ID transmitted to the broadcast packet data, the broadcast service data rate, the transmission period of the data, the number of transmission slots, and the transmission offset of the broadcast packet data is used. Broadcast service data transmission method of a high-speed data transmission system comprising the step of transmitting to the terminal. The method of claim 1, The transmitting is a broadcast service data transmission method of a high speed data transmission system, characterized in that performed in the call setup process between the user terminal and the base station. The method of claim 1, And receiving the broadcast packet data by using the common MAC ID and the transmission structure information of the broadcast packet data. The method of claim 3, wherein And the user terminal decodes the broadcast packet data by using the transmission structure information of the broadcast packet data. Allocating a MAC ID to which broadcast packet data is to be transmitted at a base station when providing a broadcast service; Determining a transmission data packet structure based on a service request data transmission rate of a broadcast, the number of transmission slots, and a transmission offset value of a broadcast packet, and transmitting the transmission data packet structure to a user terminal; And And transmitting the broadcast packet data to the user terminal by a scheduler for performing a broadcast service at the base station. The method of claim 5, wherein The scheduler for performing the broadcast service transmits a synchronous packet when the sync packet is transmitted, or calculates the number of slots that can be transmitted, and is a broadcast packet data transmission location. If there is a process of transmitting broadcast packet data, and if there is an Async. Transmission packet when the broadcast packet transmission location is not or there is no broadcast transmission packet data, the slot of the asynchronous packet is less than or equal to the number of slots that can be transmitted. If there are no asynchronous packets, and if there are no asynchronous packets or if the slots of the asynchronous packets are larger than the number of available slots, a scheduling algorithm is performed to select a transport packet smaller than the number of slots available for transmission and transmit traffic packet data. High speed characterized by consisting of processes Broadcast service data transmission method of a data transmission system.

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