CN1984111A - Transmission and use for controlling information in OFDM system - Google Patents

Abstract

The present invention provides a transmission method of control information in an OFDM system and its application. By dividing the control information such as TPS into different priorities, the control information of different priorities is modulated by modulation methods of different priorities, so that the equal Control information with different priorities in the channel environment, such as TPS, has different reception effects. In this way, by dividing relatively important control information into high-priority control information and relatively unimportant control information into low-priority control information , and the high-priority modulation method is used to modulate the high-priority control information, and the low-priority modulation method is used to modulate the low-priority control information, so that the discarded control information is often relatively unimportant control information, It ensures that the relatively important control information can be normally received by the receiving end; thereby realizing the purpose of improving the receiving performance of the receiving end in the OFDM system.

Description

Transmission method and application of control information in a kind of OFDM system

technical field

The invention relates to the technical field of network communication, in particular to a method for transmitting control information in an OFDM system, a sending end network device in the OFDM system, and the OFDM system.

Background technique

OFDM (Orthogonal Frequency Division Multiplex, Orthogonal Frequency Division Multiplex) technology is a multi-carrier digital communication modulation technology. Because OFDM has higher spectrum utilization and good anti-multipath interference ability, it is used in Europe and Australia. Broadband data communication, digital audio broadcasting, high-definition digital TV and wireless local area network of broadcasting channels. OFDM is also regarded as one of the core technologies of the fourth generation mobile communication.

The introduction of OFDM technology is actually to improve the spectrum utilization of the carrier. The feature of OFDM is that each subcarrier is orthogonal to each other, and the modulated spectrum can overlap with each other, thereby avoiding mutual interference between subcarriers.

TPS (transmission parameter signal, transmission parameter signaling) is a dedicated transmission parameter signaling. TPS can provide a robust and accessible signaling mechanism for the system. TPS can enable the receiver to discover services faster, even at low C /N (signal-to-noise ratio), the demodulator can still quickly obtain transmission parameters, and perform correct data demodulation and decoding.

TPS is mainly used to transmit signaling parameters, and TPS is signaling related to channel coding and modulation parameters. The information transmitted by TPS is shown in Table 1.

Table 1

number of digits illustrate transfer mode 2 Corresponding to 2k, 4k, 8k transmission mode, 00 means 2K, 01 means 4K, 10 means 8k.

guard interval 2 The ratio of the guard interval (00 corresponds to 1/4, 01 corresponds to 1/8, 10 corresponds to 1/16). Modulation 2 00 means QPSK, 01 means 16QAM, 10 means 64QAM encoding rate 2 00 means 1/2, 01 means 2/3, 10 means 3/4 Community sign 16 Cell ID. frame number 8 Represents the sequence number of a frame in a superframe The number of frames in a superframe 8 Indicates the number of frames in a superframe program information twenty four The characteristics of the program itself reserved bit 8

In Table 1, the information transmitted by TPS includes: program information, frame sequence number, mapping method of modulation constellation, coding rate, guard interval, OFDM transmission mode, number of frames in a superframe, and cell logo.

When forming an OFDM symbol, the sending end first fills the TPS control signal in the OFDM symbol according to the information provided by the control module of the sending end, and then fills the user's data information into the remaining subcarrier positions in turn after completing this work.

The receiving end obtains various control parameters and physical layer parameters through the received TPS, and notifies the control module of the receiving end, and compares some verification parameters with the judgment result of the receiving end.

The existing TPS-based sending method includes the following steps:

1. Generate TPS according to the control information. The TPS here has no priority, that is, all TPS have the same priority.

2. Encode the TPS.

3. Modulate the encoded TPS.

4. Fill in the TPS signal at the corresponding subcarrier position according to the input position mapping table.

The existing receiving method based on TPS signaling includes the following steps:

1. Perform synchronization and channel estimation on the received signal, and return TPS information.

2. Deconstellation mapping and decoding of TPS.

3. Save the decoded TPS for use by subsequent modules.

Considering the importance of TPS, the receiving end must accurately decode the original data of TPS. Since the amount of TPS data transmitted by BPSK (Binary Phase Shift Keying) and QPSK (Quadrature Phase Shift Keying) modulation methods is relatively small, when a large amount of TPS data needs to be transmitted, it is necessary to consider the modulation method of 16QAM, or even 64QAM modulation method. However, if the 16QAM or 64QAM modulation mode is adopted, the transmission performance of the system will be degraded.

The importance of the information represented by the bits in the TPS is different. Some bits of information are very important parameters for the receiving end, and high-performance reception must be guaranteed, while some bits of information are only used as the last Check data, its importance is relatively low. In the existing TPS transmission method, the sender adopts the same treatment method for the bit information in TPS. In this way, relatively important information may be lost, but relatively unimportant information may be lost. However, the information can be received normally, so that the reception performance of the receiving end is poor.

Contents of the invention

The object of the present invention is to provide a method for transmitting control information in an OFDM system, a sending end network device and an OFDM system, by dividing the control information into different priorities, and using different modulation methods for control information of different priorities, The reception effects of control information with different priorities under the same channel environment are different, thereby ensuring that relatively important control information can be normally received by the receiving end, and improving the receiving performance of the OFDM system receiving end.

In order to achieve the above object, a method for transmitting control information in an OFDM system provided by the present invention, the method comprises steps:

a. The sender divides the control information into different priorities;

b. The sender encodes and interleaves control information with different priorities respectively;

c. The sending end modulates the coded and interleaved control information of different priorities by using modulation methods of different priorities;

d. The transmitting end fills in the modulated control information at the corresponding subcarrier position, and sends it to the receiving end.

The control information is: information carried in the transmission parameter signaling TPS, or system configuration information.

The priority includes two or more;

When the priority includes: high priority and low priority, the high priority control information includes: transmission mode, guard interval, modulation mode, coding rate, and the low priority control information includes: frame sequence number, super The number of frames in a frame, program information, cell logo, and reserved bits.

The step of encoding the control information of different priorities in the step b includes:

The sender encodes control information of different priorities using the same encoding rate; or the sender encodes control information of different priorities using different encoding rates;

The step of interleaving the control information of different priorities in the step b includes:

The sending end uses the same interleaving method for TPs of different priorities to perform interleaving; or the sending end uses different interleaving methods for TPs of different priorities to perform interleaving.

Said step c comprises:

The sender uses 16QAM modulation with different priorities to modulate coded and interleaved control information with different priorities; or the sender uses 64QAM modulation with different priorities to modulate coded and interleaved control information with different priorities ; or the sending end uses 256QAM modulation modes of different priorities to modulate the coded and interleaved control information of different priorities.

The present invention provides a sending end network device in an OFDM system, wherein the network device is provided with a priority storage module, a coding interleaving module, a modulation module and a sending module;

The priority storage module is used for: storing priority information corresponding to each control information;

The encoding and interleaving module is used to: respectively encode and interleave control information of different priorities according to the information stored in the priority storage module, and send the encoded and interleaved control information to the modulation module;

The modulation module is used to: use different priority modulation methods to modulate the coded and interleaved control information of different priorities according to the information stored in the priority storage module, and send the modulated control information to the sending module;

The sending module is used for: filling the received modulated control information into the corresponding subcarrier position, and sending it to the receiving end.

The information stored in the priority storage module includes:

Correspondence between transmission mode, guard interval, modulation method, coding rate and high priority; frame number, number of frames in a superframe, program information, cell logo, reserved bit and low priority.

The encoding and interleaving module uses the same encoding rate to encode and interleave the control information of different priorities according to the information stored in the priority storage module, and sends the encoded and interleaved control information to the modulation module; or the encoding and interleaving module according to the priority The information stored in the storage module uses different encoding rates to encode and interleave control information with different priorities, and sends the encoded and interleaved control information to the modulation module.

The modulation module modulates the coded and interleaved control information of different priorities by using 16QAM modulation methods of different priorities according to the information stored in the priority storage module, and sends the modulated control information to the sending module; or the modulation module transmits the control information according to the priority The information stored in the storage module adopts the 64QAM modulation method of different priority to modulate the coded and interleaved control information of different priority, and sends the modulated control information to the sending module; or the modulation module stores the information according to the priority storage module. The information adopts the 256QAM modulation method of different priorities to modulate the coded and interleaved control information of different priorities, and sends the modulated control information to the sending module.

The present invention also provides an OFDM system, comprising: a receiving end and a sending end, wherein the network equipment of the sending end is provided with a priority storage module, a coding interleaving module, a modulation module and a sending module;

The priority storage module is used for: storing priority information corresponding to each control information;

The encoding and interleaving module is used to: respectively encode and interleave control information of different priorities according to the information stored in the priority storage module, and send the encoded and interleaved control information to the modulation module;

The modulation module is used to: use different priority modulation methods to modulate the coded and interleaved control information of different priorities according to the information stored in the priority storage module, and send the modulated control information to the sending module;

The sending module is used to: fill the received modulated control information into the corresponding subcarrier position, and send it to the receiving end;

The receiving end is used to: perform synchronization and channel estimation on the received control information, obtain the control information after synchronization and channel estimation, and perform deconstellation mapping on the obtained control information, and then perform deinterleaving and decoding processing on the control information, The deinterleaved and decoded control information is used by the receiving end.

From the description of the above technical solution, it can be seen that the present invention divides the control information into different priorities, and uses modulation methods of different priorities to modulate the control information of different priorities, so that the control information of different priorities under the same channel environment The receiving effect of the information is different. In this way, by dividing relatively important control information into high priority control information, relatively unimportant control information into low priority control information, and using high priority control information for high priority control information The priority modulation method is used for modulation, and the low priority control information is modulated by a low priority modulation method, so that the discarded information is often relatively unimportant control information, so that relatively important control information can be received normally; The control information in the invention can be divided into two priority levels or more than two priority levels according to actual needs, and the modulation in the present invention can adopt modulation methods such as 16QAM, or 64QAM, or 256QAM; The scheme achieves the purpose of improving the receiving performance of the receiving end.

Description of drawings

Fig. 1 is a schematic diagram of the principle of realizing TPS transmission of the present invention;

Fig. 2 is a schematic diagram of hierarchical modulation of TPS with different priorities according to an embodiment of the present invention.

Detailed ways

Control information, such as the information represented by different bits in TPS, has different importance. If the sending end can adopt different modulation processing methods for bit information of different importance in TPS, it can ensure that relatively important control information is received by the receiving end. For normal reception, the discarded information should be relatively unimportant control information.

The control information in the present invention may be information carried in the TPS, or system configuration information. System configuration information such as: system frequency point, system bandwidth, system clock, system sampling frequency, etc. The technical solution provided by the present invention will be described in detail below by taking the TPS transmission method as an example.

Aiming at the defects of TPS transmission in the prior art, the realization principle of the TPS transmission method proposed by the present invention is shown in FIG. 1 .

In Fig. 1, the information in the TPS needs to be divided into different priorities, and the information included in a TPS should have the same priority. The TPS adopts different priority modulation methods for modulation processing, that is, layered modulation is performed on the TPS, and the layered modulated TPS is sent to the receiving end after being framed. In this way, the present invention can make TPSs with different priorities have different reception effects under the same channel environment, so that TPSs with high priorities can have good reception effects, so as to ensure that important information can be received normally.

The present invention can divide the control information, that is, the information included in the current TPS into two different priorities, and of course, the information included in the current TPS can also be divided into more than two different priorities. The principle for dividing the control information into different priorities is: the importance of the control information. That is to say, the relatively important information in the control information has a high level of priority, and the relatively unimportant information in the control information has a low level of priority.

Taking the division of control information into two priority levels as an example, the method provided by the present invention and the network device at the sending end will be described with reference to FIG. 2 .

In Figure 2, first, the sender needs to divide the control information into high-priority control information and low-priority control information according to the importance of the control information. The high-priority information can include: transmission mode, guard interval, modulation mode , encoding rate, etc., low priority information may include: frame number, number of frames in a superframe, program information, cell logo, reserved bits, etc.

After distinguishing the priorities of the control information, the sender needs to transmit information of different priorities through different TPSs. In this way, TPSs also have different priorities, that is, TPSs carrying high-priority information are high-priority TPS, the TPS carrying low-priority information is low-priority TPS.

Since the control information is divided into high-priority control information and low-priority control information in this embodiment, the composition of the high-priority TPS may include the following content:

Transmission mode: 2 bits, 00 means 2k, 01 means 4k, 10 means 8k;

Guard interval: 2 bits, 00 means 1/4, 01 means 1/8, 10 means 1/16;

Modulation method: 2 bits, 00 means QPSK, 01 means 16QAM, 10 means 64QAM;

Coding rate: 2 bits, 00 means 1/2, 01 means 2/3, 10 means 3/4;

The composition of low priority TPS can include the following:

Frame number: 8 bits, indicating the frame number;

The number of frames in a superframe: 8 bits, indicating the number of frames in a superframe;

Program information: 24 bits, indicating the characteristics of the program itself;

Cell logo: 16 bits, indicating the cell ID;

Reserved bits: 8 bits.

After generating TPSs with different priorities, the sender needs to encode the TPSs with different priorities respectively. In the present invention, TPSs of different priorities can adopt the same encoding rate, and can also adopt different encoding rates, such as high-priority TPS can adopt 1/2, or 2/3, or 3/4 encoding rate, The low priority TPS can also adopt the encoding rate of 1/2, 2/3, or 3/4.

After encoding the TPSs of different priorities, the sender needs to interleave the encoded TPSs of different priorities. The interleaving here can be convolutional interleaving or symbolic interleaving, and TPSs of different priorities can be used The same interleaving processing method may also adopt different interleaving processing methods.

After performing interleaving processing on the TPSs of different priorities, the sending end needs to modulate the interleaved TPSs of different priorities using different modulation modes. That is to say, the transmitting end maps TPSs of different priorities after interleaving to different bits of constellation symbols of a modulation mode, such as mapping TPSs of different priorities to different bits of 16QAM constellation symbols, such as different Priority TPSs are mapped to different bits of the 64QAM constellation symbol, for example, TPSs of different priorities are mapped to different bits of the 256QAM constellation symbol. Here, the high-priority TPS should be mapped to the high bit of the modulation mode, and the low-priority TPS should be mapped to the low bit of the modulation mode.

When using the 16QAM modulation method to modulate TPSs of different priorities, the high-priority TPS should be mapped to the high bits of the 16QAM modulation method, that is, the high-priority QPSK modulation method should be used for the high-priority TPS The TPS is modulated; the low-priority TPS should be mapped to the low bit of the 16QAM modulation mode, that is, the low-priority TPS is modulated by the low-priority QPSK modulation mode. Through the above modulation, the present invention can map TPSs with different priorities to different layers of 16QAM, thereby realizing layered modulation.

The modulation modes of TPS with different priorities in the present invention are not limited to the 16QAM, 64QAM and 256QAM modulation modes described above.

After the above modulation is performed, the sending end can fill in the TPS signal at the corresponding subcarrier position according to the position mapping table, so that TPS with different priorities can be sent to the receiving end through the subcarrier.

The receiving end can use the existing TPS-based receiving method to receive the TPS with different priorities sent by the sending end, and the method for receiving the TPS at the receiving end may include the following steps:

Step 1. The receiving end performs synchronization and channel estimation on the received signal, and obtains TPS information after synchronization and channel estimation.

Going to step 2, the receiving end performs constellation demapping on the acquired TPS information after synchronization and channel estimation.

In step 3, the receiving end deinterleaves and decodes the TPS.

In step 4, the receiving end saves the decoded TPS for use by subsequent modules.

Due to the existence of interference and noise in the actual transmission process, the position of the constellation points of the TPS signal after the above layered modulation is transmitted through the actual channel will change, some constellation points may be close, and the close constellation points are prone to misjudgment , the greater the Euclidean distance between constellation points, the smaller the probability of misjudgment, that is, the larger the Euclidean distance between constellation points, the stronger the anti-interference ability of TPS information.

Since the Euclidean distance corresponding to the high-priority QPSK modulation method is large, and the Euclidean distance corresponding to the low-priority QPSK modulation method is small, the TPS after layered modulation has different anti-interference capabilities, that is, the high-priority TPS The signal has a higher anti-interference ability, and the low-priority TPS signal has a lower anti-interference ability.

The TPS transmission method described in the above embodiments can be extended to 64QAM, 256QAM modulation modes, etc. For example, when 64QAM modulation mode is adopted, high-priority TPS can be modulated by 64QAM high-priority QPSK, and low-priority TPS can be It is modulated by low priority QPSK of 64QAM. The basic principle of its realization is the same as the above-mentioned realization principle of adopting the 16QAM modulation mode, and will not be described in detail here.

In addition, the above embodiment describes the TPS transmission process by taking the two priority levels of high priority and low priority as an example. The TPS priority in the present invention can also be divided into two or more priorities, such as dividing TPS into three priorities of high priority, medium priority, and low priority, etc., when TPS is divided into three different priorities , the TPSs with three different priorities should be modulated by different priority modulation methods. For example, the high-priority TPS can be modulated by 64QAM high-priority QPSK mode, and the medium-priority TPS can be modulated by 64QAM medium The priority QPSK mode is used for modulation, and the low-priority TPS can be modulated by the low-priority QPSK mode of 64QAM. Similarly, the above description can be extended to the 256QAM modulation mode.

From the description of the above technical solution, it can be seen that the sending end of the present invention divides the information contained in the current TPS into high priority information and low priority information, and modulates information of different priorities through different priority modulation methods to ensure The receiving effect of high-priority information is better than that of low-priority information under the same channel environment. In this way, after the sending end adopts the TPS transmission method of the present invention, it can ensure that the receiving performance of the receiving end is better than that of the currently unused layered Reception performance when modulated.

The TPS transmission method with different priorities of the OFDM (Orthogonal Frequency Division Multiplex) system provided by the present invention is suitable for data communication systems in various environments such as ground and satellite.

The above embodiments are described by taking TPS as an example. When the transmitting end in the OFDM system sends other control information such as system configuration information, its implementation principle and specific implementation process are basically the same as the above description, and will not be described in detail here.

The TPS sending end network equipment in the OFDM system provided by the present invention is provided with a priority storage module, a coding and interleaving module, a modulation module and a sending module.

The priority storage module is mainly used to store the priority information corresponding to each control information, that is, to store the corresponding relationship between the control information and the priority level, such as storing the corresponding relationship between each information carried in the TPS and the priority level, etc. The priority of control information is determined according to the importance of the information. The control information stored in the priority storage module can be divided into two different priorities, and of course, can also be divided into more than two different priorities. When the information stored in the priority storage module is divided into two different priorities: high priority and low priority, the high priority information can include: transmission mode, guard interval, modulation method, coding rate, etc., low priority information It can include: frame number, number of frames in a superframe, program information, cell logo, reserved bits, etc. That is to say, the priority storage module stores the corresponding relationship between transmission mode, guard interval, modulation method, coding rate and high priority, as well as frame number, number of frames in a superframe, program information, cell logo, and reserved bits Correspondence with low priority. Specifically as described in the above method.

The coding and interleaving module is mainly used for: according to the information stored in the priority storage module, the control information of different priorities to be sent by the sending end, such as TPS, is respectively coded and interleaved. Here, the encoding and interleaving module can encode TPSs of different priorities using different encoding rates, and can also encode TPSs of different priorities using the same encoding rate. Moreover, the encoding and interleaving module can use different encoding rates for TPSs of different priorities. TPSs of different priorities can also be processed in the same interleaving manner, specifically as described in the above method. The encoding and interleaving module sends the encoded and interleaved TPS to the modulation module.

The modulation module is mainly used for: using different priority modulation methods to modulate different priority, coded and interleaved control information such as TPS according to the information stored in the priority storage module, and send the modulated TPS to the sending module. The modulation method of the TPS by the modulation module realizes the function of hierarchically modulating the TPS of different priorities.

The modulation module can use different priority 16QAM modulation methods to modulate different priority, coded and interleaved control information such as TPS according to the information stored in the priority storage module, and send the modulated TPS to the sending module, that is, the modulation module The high-priority TPS should be mapped to the high bits of the 16QAM modulation mode, and the low-priority TPS should be mapped to the low bits of the 16QAM modulation mode, that is, the modulation module should adopt the high-priority QPSK modulation mode To modulate the high-priority TPS, the low-priority TPS should be modulated in the low-priority QPSK modulation mode. Through the above modulation process, the modulation module can map TPSs with different priorities to different layers of 16QAM, thereby realizing hierarchical modulation. Certainly, the modulating module can also adopt different priority 64QAM modulation modes to modulate the TPS after encoding and interleaving with different priorities according to the information stored in the priority storage module, and send the modulated TPS to the sending module. The module can also use 256QAM modulation methods of different priorities to modulate the coded and interleaved TPS of different priorities according to the information stored in the priority storage module, and send the modulated TPS to the sending module. Specifically as described in the above method.

The sending module is mainly used for filling the received modulated control information such as TPS into the corresponding subcarrier position, and sending it to the receiving end. Since the Euclidean distance corresponding to the high-priority QPSK modulation method is large, and the Euclidean distance corresponding to the low-priority QPSK modulation method is small, the TPS sent by the sending module has different anti-interference capabilities, that is, the high-priority TPS signal It has high anti-jamming capability, and low-priority TPS signals have low anti-jamming capability. In this way, at the receiving end, the high-priority TPS can have a good receiving effect, ensuring that relatively important information can be received normally, and discarded information is often relatively unimportant information, thereby improving the receiving performance of the receiving end.

The OFDM system provided by the present invention includes: a receiving end and a sending end. Here, the network device at the sending end is provided with a priority storage module, a coding and interleaving module, a modulation module, and a sending module. The specific operations of these four modules at the sending end are as described in the above-mentioned embodiments, and will not be described in detail here. .

The receiving end can use various existing receiving methods to receive and process the control information sent by the sending end, such as the TPS signal. For example, the receiving end first performs synchronization and channel estimation on the received TPS signal, and obtains the TPS signal after synchronization and channel estimation. information. Secondly, the receiving end performs deconstellation mapping on the TPS information obtained above, then, the receiving end deinterleaves and decodes the TPS, and finally, the receiving end saves the deinterleaved and decoded TPS for use by subsequent modules of the receiving end .

Although the present invention has been described by way of example, those of ordinary skill in the art know that there are many variations and changes in the present invention without departing from the spirit of the invention, and the claims of the application document of the present invention include these variations and changes.

Claims (10)

1. A method for transmitting control information in an OFDM system, comprising: a. The sender divides the control information into different priorities; b. The sender encodes and interleaves control information with different priorities respectively; c. The sending end modulates the coded and interleaved control information of different priorities by using modulation methods of different priorities; d. The transmitting end fills in the modulated control information at the corresponding subcarrier position, and sends it to the receiving end. 2. The method for transmitting control information in an OFDM system according to claim 1, wherein the control information is information carried in the transmission parameter signaling (TPS) or system configuration information. 3. The method for transmitting control information in an OFDM system according to claim 1 or 2, wherein the priority includes two or more types; When the priority includes: high priority and low priority, the high priority control information includes: transmission mode, guard interval, modulation mode, coding rate, and the low priority control information includes: frame sequence number, super The number of frames in a frame, program information, cell logo, and reserved bits. 4. The method for transmitting control information in an OFDM system according to claim 1 or 2, characterized in that: The step of encoding the control information of different priorities in the step b includes: The sender encodes control information of different priorities using the same encoding rate; or the sender encodes control information of different priorities using different encoding rates; The step of interleaving the control information of different priorities in the step b includes: The sending end uses the same interleaving method for TPs of different priorities to perform interleaving; or the sending end uses different interleaving methods for TPs of different priorities to perform interleaving. 5. The method for transmitting control information in an OFDM system according to claim 1 or 2, wherein said step c comprises: The sender uses 16QAM modulation with different priorities to modulate coded and interleaved control information with different priorities; or the sender uses 64QAM modulation with different priorities to modulate coded and interleaved control information with different priorities ; or the sending end uses 256QAM modulation modes of different priorities to modulate the coded and interleaved control information of different priorities. 6. A sending end network device in an OFDM system, characterized in that the network device is provided with a priority storage module, a coding interleaving module, a modulation module and a sending module; The priority storage module is used for: storing priority information corresponding to each control information; The encoding and interleaving module is used to: respectively encode and interleave control information of different priorities according to the information stored in the priority storage module, and send the encoded and interleaved control information to the modulation module; The modulation module is used to: use different priority modulation methods to modulate the coded and interleaved control information of different priorities according to the information stored in the priority storage module, and send the modulated control information to the sending module; The sending module is used for: filling the received modulated control information into the corresponding subcarrier position, and sending it to the receiving end. 7. The sending-end network device in an OFDM system according to claim 6, wherein the information stored in the priority storage module includes: Correspondence between transmission mode, guard interval, modulation method, coding rate and high priority; Frame number, number of frames in a superframe, program information, cell logo, correspondence between reserved bits and low priority. 8. The sending-end network device in an OFDM system as claimed in claim 6, wherein the encoding and interleaving module uses the same encoding rate to encode the control information of different priorities respectively according to the information stored in the priority storage module , interleaving, and send the encoded and interleaved control information to the modulation module; or the encoding and interleaving module uses different encoding rates to encode and interleave the control information of different priorities according to the information stored in the priority storage module, and encodes , and send the interleaved control information to the modulation module. 9. The TPS sending end network device in an OFDM system according to claim 6, 7 or 8, characterized in that: The modulation module modulates the coded and interleaved control information of different priorities by using 16QAM modulation methods of different priorities according to the information stored in the priority storage module, and sends the modulated control information to the sending module; or the modulation module transmits the control information according to the priority The information stored in the storage module adopts the 64QAM modulation method of different priority to modulate the coded and interleaved control information of different priority, and sends the modulated control information to the sending module; or the modulation module stores the information according to the priority storage module. The information adopts the 256QAM modulation method of different priorities to modulate the coded and interleaved control information of different priorities, and sends the modulated control information to the sending module. 10. An OFDM system based on claim 5, comprising: a receiving end and a sending end, characterized in that, the network equipment at the sending end is provided with a priority storage module, a coding interleaving module, a modulation module and a sending module; The priority storage module is used for: storing priority information corresponding to each control information; The encoding and interleaving module is used to: respectively encode and interleave control information of different priorities according to the information stored in the priority storage module, and send the encoded and interleaved control information to the modulation module; The modulation module is used to: use different priority modulation methods to modulate the coded and interleaved control information of different priorities according to the information stored in the priority storage module, and send the modulated control information to the sending module; The sending module is used to: fill the received modulated control information into the corresponding subcarrier position, and send it to the receiving end; The receiving end is used to: perform synchronization and channel estimation on the received control information, obtain the control information after synchronization and channel estimation, and perform deconstellation mapping on the obtained control information, and then perform deinterleaving and decoding processing on the control information, The deinterleaved and decoded control information is used by the receiving end.