CN101163319B - A method and communication system for reading broadcast frames - Google Patents

Abstract

The present invention belongs to the field of wireless access technology, and provides a method and device for reading broadcast frames. The method specifically includes: firstly reading the information in the anchor broadcast frame that does not require a broadcast frame mode indication, and then reading the broadcast frame mode, According to the read broadcast frame mode, judge whether it contains spectrum information, if so, read the spectrum information, determine the bandwidth of the cruising broadcast frame according to the spectrum information, and then read the system indicated by the broadcast frame mode in the anchor broadcast frame and cruising broadcast frame Broadcast information; otherwise, read the system broadcast information indicated by the broadcast frame mode in the anchor broadcast frame. The present invention shortens the search time of the terminal when receiving system signals, and the frame structure of the broadcast frame used in the present invention improves the utilization rate of frequency spectrum.

Description

A method and communication system for reading broadcast frames

technical field

The invention relates to the field of wireless access technology, in particular to a technology for reading broadcast frames.

Background technique

With the rapid development of high-speed network technology and multimedia technology, the wireless network has evolved from circuit switching to packet switching, and various wireless broadband access technologies have emerged one after another. Among them, in the super three-generation mobile communication system B3G/4G, the bandwidth varies widely. , can range from a few MHz to hundreds of MHz, and can work in both low-bandwidth and high-bandwidth situations, which requires consideration of multiple bandwidths in system design, so that in low-bandwidth situations, The system can work normally, and in the case of high bandwidth, the spectrum can be fully utilized. However, in the existing technology, each physical channel is multiplexed in a relatively fixed frame structure. When the transmission bandwidth increases, the broadcast data does not increase linearly, the spectrum utilization rate decreases, and the search time of the terminal when receiving the signal increases. ; When the transmission bandwidth is reduced, the spectrum resources are insufficient, and each physical channel cannot be carried.

The relatively fixed multiplexing for each physical channel is in the frame structure. For example, in Code Division Multiple Access 2000 Air Interface Evolution CDMA2000 AIE, a superframe is composed of a preamble frame and a normal frame, and the preamble frame is used to send synchronization code, pilot frequency and system broadcast information. Forward link physical broadcast channel 0, which sends basic system information, such as system version, number of antennas, etc., is located in No. 0 OFDM symbol, occupying a fixed subcarrier; forward link physical broadcast channel 1 , to send the forward information channel of the system, and the terminal can receive the signaling of the forward channel according to this information: the position is 0 to 4 OFDM symbols, occupying a fixed subcarrier; the common pilot channel of the previous link, Used for channel estimation, the position is 0 to 1 OFDM symbol, occupying a fixed subcarrier; the forward link learns the channel, sends a synchronization code, and the terminal performs system synchronization according to the synchronization code, and the position is 5 to 6 Orthogonal frequency division multiplexing OFDM symbol No. 7, occupying all subcarriers; interference from other cells in the forward link, sending synchronization code and interference information of other cells, located at No. 7 OFDM symbol, occupying all subcarriers subcarrier.

Contents of the invention

The problem to be solved by the present invention is to provide a method for reading broadcast frames and a communication system. When the transmission bandwidth changes, the method can improve the utilization rate of the frequency spectrum and shorten the search time for the terminal to receive the signal.

In order to solve the problems of the technologies described above, the purpose of the present invention is achieved through the following technical solutions:

An embodiment of the present invention provides a method for reading broadcast frames, including:

The terminal reads the broadcast frame mode; the broadcast frame includes an anchor broadcast frame and a cruising broadcast frame, the anchor broadcast frame is transmitted at a fixed frequency with a fixed frequency bandwidth, and the cruising broadcast frame is based on system planning and configuration or spectrum sharing Determine the bandwidth and transmission information, the broadcast frame mode is used to indicate the system broadcast information contained in the broadcast anchor broadcast frame and cruising broadcast frame;

If the broadcast frame indicated by the broadcast frame mode contains spectrum information, read the spectrum information first, and then read the broadcast information in the broadcast frame except the spectrum information, otherwise, directly read the broadcast frame specified by the broadcast frame mode The indicated broadcast message.

The present invention also provides a communication system, including: a base station and a user terminal;

The above-mentioned base station is used to send broadcast information to the user terminal through a broadcast frame. The broadcast frame includes an anchor broadcast frame and a cruise broadcast frame. The anchor broadcast frame is transmitted at a fixed frequency with a fixed frequency bandwidth, and the cruise broadcast frame is transmitted according to the system planning. The frequency bandwidth and the information to be transmitted are determined by the configuration situation or the spectrum sharing situation;

The user terminal is configured to read the broadcast frame mode from the base station, the broadcast frame mode is used to indicate the system broadcast information contained in the broadcast anchor broadcast frame and cruising broadcast frame, if the broadcast frame mode indicates If the broadcast information includes spectrum information, read the spectrum information first, and then read the broadcast information except the spectrum information in the broadcast frame; otherwise, directly read the broadcast information indicated by the broadcast frame mode in the broadcast frame.

The present invention reads the broadcast frame mode by the terminal, and directly judges whether spectrum information is included according to the indication of the broadcast frame mode. and the frame structure adopted in the reading process of the present invention is that a superframe includes a broadcast frame and several adjacent data frames. When the bandwidth is insufficient, the broadcast frame mode only indicates some necessary information, and the remaining The broadcast information is placed in adjacent data frames. When the bandwidth increases, various types of system broadcast information are organized in the broadcast frame, thereby improving the utilization rate of the spectrum.

Description of drawings

Fig. 1 is a frame structure diagram of a broadcast frame of the present invention;

Fig. 2 is a flow chart of Embodiment 1 of the present invention;

Fig. 3 is the flowchart of the second embodiment of the present invention;

Fig. 4 is a device diagram of the present invention.

Detailed ways

The present invention provides a method for reading broadcast frames. In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and examples.

Referring to Fig. 1, it is a frame structure diagram of a broadcast frame of the present invention. Each superframe is composed of a broadcast frame and several adjacent data frames. The broadcast frame is divided into an anchor broadcast frame and a cruising broadcast frame in terms of frequency. It is transmitted on a fixed frequency with a fixed frequency bandwidth, and the cruising broadcast frame determines the frequency bandwidth and transmitted information according to the system planning and configuration or the spectrum sharing situation.

The anchor broadcast frame contains broadcast frame mode and spectrum information. The broadcast frame mode is used to indicate the mode of the broadcast frame, that is, which system broadcast information to be transmitted is included in the broadcast anchor broadcast frame and cruising broadcast frame. Through the indication of the broadcast frame mode, various types of system broadcast information are organized in the broadcast frame. But when the bandwidth is insufficient, only some important necessary information is indicated, such as downlink channel parameters, and the remaining system broadcast information is placed in adjacent data frames; when the bandwidth increases, some other system broadcast information is indicated according to the size of the bandwidth , such as uplink channel parameters, cell and adjacent cell parameters, broadcast-multicast service control parameters, broadcast-multicast service data, etc. The spectrum information is used to indicate the bandwidth of the cruising broadcast frame and the uplink and downlink bandwidth of other frames.

Wherein, the anchor broadcast frame may also include basic system information and paging. Basic information of the system, including system version, antenna configuration, etc.

Wherein, when the system broadcast information cannot fit in one superframe, it can be placed in adjacent superframes.

For the frame structure of the broadcast frame, the following example describes it in detail:

For example, each superframe is composed of a broadcast frame and several adjacent data frames, the length of the superframe is 10ms, the bandwidth of the anchor broadcast frame is 1.25MHz, and the broadcast control channel BCCH in the broadcast frame contains the system broadcast message BCCHr, System basic information BCCH1, BCCH2, spectrum information BCCH3, other system broadcast information BCCHo and synchronization channel SYNC.

The broadcast control channel BCCH is used to carry system broadcast messages;

The system broadcast message BCCH of the relay station occupies one OFDM symbol. As the bandwidth increases, the system broadcast message of the relay station also increases. For each superframe, the information broadcast by the relay station may change, so the period of BCCHr is a superframe;

The basic system information BCCH1, such as system version, antenna configuration, etc., contains less data and will only change when the system is reconfigured, so the change is very slow. Considering the delay of reception, the performance of reception and the data size of BCCH1 itself, 32 superframes are used as the cycle, and one OFDM symbol in the anchor broadcast frame is always occupied in one cycle, and repeated coding or other coding methods can be used;

BCCH2, including broadcast frame mode, downlink parameters, paging message, each super frame contains BCCH2, each BCCH2 contains broadcast frame mode, the control field in BCCH2 indicates whether to contain downlink parameters and paging Message, the broadcast frame mode is identified by 5 bits, each bit indicates whether it contains BCCH3, BCCH4, BCCH5, BCCH6, BCCH7;

Spectrum information BCCH3 indicates the uplink and downlink bandwidth of the entire system, so that the bandwidth of the cruising broadcast frame can be known, that is, the downlink bandwidth minus the bandwidth of the anchor broadcast frame. Due to the delay of the terminal, the receiving performance is different from the data size of BCCH3 itself Consistency in bandwidth, the cycle of BCCH3 is 128 superframes, and occurs every 128 superframes;

BCCHo, other system broadcast information, including the unfinished BCCH2 information in the anchor broadcast frame, uplink channel parameters BCCH4, cell and adjacent cell parameters BCCH5, broadcast multicast service control parameters BCCH6, including broadcast multicast service data BCCH7;

The synchronization channel SYNC is used by the terminal to establish downlink synchronization, and the period is one superframe.

Referring to Fig. 2, it is the flowchart of example one for the present invention, and realizing the present invention comprises the following steps:

Step 201: Read the broadcast frame mode, which indicates which broadcast information is contained in the broadcast information, such as spectrum information, downlink channel parameters, uplink channel parameters, cell and adjacent cell parameters, broadcast multicast service control parameters, broadcast multicast service data, etc.;

Step 202: According to the broadcast information indicated by the read broadcast frame mode, it is judged whether spectrum information is included, if so, execute step 204, otherwise, execute step 203;

Step 203: Read the broadcast information indicated by the broadcast frame mode in the anchor broadcast frame, and then perform step 206;

Step 204: read the spectrum information, and determine the bandwidth of the cruising broadcast frame and the uplink and downlink bandwidth of other frames according to the spectrum information;

Step 205: Read the system broadcast information except spectrum information indicated by the broadcast frame mode in the anchor broadcast frame and the cruising broadcast frame;

So far, the reading of the broadcast frame in a superframe has been completed. If a superframe cannot fit the system broadcast information, the following steps should be included after step 203 or step 205:

Step 206: Determine whether the broadcast information of all broadcast frames has been read, and if yes, end the process; otherwise, execute step 201.

Referring to Figure 3, it is a flowchart of Embodiment 2 of the present invention, specifically including:

Step 301: Read the information in the anchor broadcast frame that does not need to be indicated by the broadcast frame mode, such as basic system information and paging;

Step 302: Read the broadcast frame mode. The broadcast frame mode indicates which broadcast information is contained in the broadcast information, such as spectrum information, downlink channel parameters, uplink channel parameters, cell and adjacent cell parameters, broadcast multicast service control parameters, broadcast multicast service data, etc.;

Step 303: According to the broadcast information indicated by the read broadcast frame mode, determine whether spectrum information is included, if so, perform step 305, otherwise, perform step 304;

Step 304: Read the broadcast information indicated by the broadcast frame mode in the anchor broadcast frame, and then perform step 307;

Step 305: Read the spectrum information, and determine the bandwidth of the cruising broadcast frame and the uplink and downlink bandwidth of other frames according to the spectrum information;

Step 306: Read the system broadcast information except spectrum information indicated by the broadcast frame mode in the anchor broadcast frame and the cruising broadcast frame;

So far, the reading of the broadcast frame in a superframe has been completed. If the system broadcast information cannot be placed in a superframe, the following steps should be included after step 304 or step 307:

Step 307: Determine whether the broadcast information of all broadcast frames has been read, and if yes, end the process; otherwise, execute step 301.

Referring to Fig. 4, it is a device diagram of the present invention, which is described in detail below:

The base station 401 is configured to send broadcast information to the user terminal 402 through a broadcast frame;

The user terminal 402 is configured to read the broadcast frame pattern from the base station 401, and judge whether spectrum information is included through the indication of the broadcast frame pattern, and if so, read the spectrum information, and then read the broadcast frame indicated by the broadcast frame pattern Otherwise, directly read the broadcast information indicated by the broadcast frame mode in the broadcast frame.

Wherein, the user terminal 402 is further configured to read the broadcast information in the broadcast frame that does not need to be indicated by the broadcast frame mode.

Wherein, the user terminal 402 is further configured to obtain the bandwidth of the broadcast frame according to the read spectrum information.

When the bandwidth is insufficient, only some necessary information is indicated, and the remaining information is placed in a data frame adjacent to the broadcast frame, and the necessary information indicated by the broadcast frame mode is read; or,

When the bandwidth increases, various types of system broadcast information are organized into broadcast frames, and various types of broadcast information indicated by the broadcast frame mode are read.

Wherein, the broadcast frame is divided into an anchor broadcast frame and a cruising broadcast frame in terms of frequency, the anchor broadcast frame is transmitted at a fixed frequency with a fixed frequency bandwidth, and the cruising broadcast frame is determined according to system planning and configuration or spectrum sharing Frequency bandwidth and information transmitted.

Wherein, the broadcast frame mode is a mode indicating a broadcast frame, that is, indicates which system broadcast information to be transmitted is included in the broadcast anchor broadcast frame and cruising broadcast frame.

The method and device for reading broadcast frames provided by the present invention have been described above in detail. In this paper, specific examples are used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only used to help understand the present invention. The method of the invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation and scope of application. In summary, the content of this specification should not be understood To limit the present invention.

Claims (9)

1. A method of reading a broadcast frame, comprising:

a terminal reads a broadcast frame mode; the broadcast frames include an anchor broadcast frame and a cruising broadcast frame, the anchor broadcast frame is transmitted at a fixed frequency with a fixed frequency bandwidth, the cruising broadcast frame determines the frequency bandwidth and the transmitted information according to the planning and configuration condition of the system or the frequency spectrum sharing condition, and the broadcast frame mode is used for indicating the system broadcast information contained in the broadcasted anchor broadcast frame and the cruising broadcast frame;

if the broadcast frame indicated by the broadcast frame mode contains the frequency spectrum information, reading the frequency spectrum information firstly, and then reading the broadcast information except the frequency spectrum information in the broadcast frame, otherwise, directly reading the broadcast information indicated by the broadcast frame mode in the broadcast frame.

2. The method of claim 1, wherein reading the broadcast frame pattern is preceded by:

and the terminal reads the information which does not need the broadcast frame mode indication in the broadcast frame.

3. The method of claim 2, wherein the terminal reading the spectrum information further comprises:

and the terminal acquires the bandwidth of the broadcast frame according to the read frequency spectrum information.

4. The method of claim 3, wherein reading the broadcast information indicated by the broadcast frame mode in the broadcast frame comprises:

when the bandwidth is insufficient, the broadcast frame mode indicates the necessary information of the system, the necessary information comprises a downlink channel parameter, the rest information is placed in a data frame adjacent to the broadcast frame, and the necessary information of the system indicated by the broadcast frame mode is read;

when the bandwidth is increased, the broadcast frame mode organizes system broadcast information in a broadcast frame, and reads the broadcast information indicated by the broadcast frame mode.

5. The method of claim 1, wherein reading the broadcast information indicated by the broadcast frame mode in the broadcast frame further comprises:

and judging whether the broadcast information of all the broadcast frames is read or not, if so, ending the reading process, and otherwise, reading the broadcast frame mode of the next broadcast frame.

6. A communication system, comprising: a base station, a user terminal;

the base station is configured to send broadcast information to a ue through broadcast frames, where the broadcast frames include anchor broadcast frames and cruising broadcast frames, the anchor broadcast frames are transmitted at a fixed frequency with a fixed bandwidth, and the cruising broadcast frames determine the bandwidth and the transmitted information according to a planning and configuration condition of a system or a spectrum sharing condition;

the user terminal is configured to read the broadcast frame mode from a base station, where the broadcast frame mode is used to indicate system broadcast information included in an anchor broadcast frame and a cruising broadcast frame of a broadcast, and if the broadcast information indicated by the broadcast frame mode includes spectrum information, read the spectrum information first, and then read broadcast information in the broadcast frame except the spectrum information, otherwise, directly read the broadcast information indicated by the broadcast frame mode in the broadcast frame.

7. The system of claim 6, wherein the user terminal is further configured to read broadcast information in a broadcast frame that does not require a broadcast frame mode indication.

8. The system of claim 7, wherein the user terminal is further configured to obtain a bandwidth of a broadcast frame according to the read spectrum information.

9. The system of claim 8, wherein the user terminal is further configured to:

when the bandwidth is insufficient, only indicating the necessary information of the system, wherein the necessary information comprises the parameters of a downlink channel, and the rest information is put in a data frame adjacent to a broadcast frame to read the necessary information of the system indicated by the broadcast frame mode; or,

when the bandwidth is increased, organizing system broadcast information in a broadcast frame, and reading the broadcast information indicated by the broadcast frame mode.

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