Cell interleaving method and system for rotating constellation in DVB-T2 standard

Abstract

The invention belongs to the technical field of communication, and discloses a cell interleaving method and system for a rotating constellation in a DVB-T2 standard, and the method comprises the steps: preparing data needing to be input, carrying out the serial-parallel conversion of the data, and carrying out the sequential representation of the data through an index; performing CELL interleaving on the data subjected to serial-parallel conversion, and performing constellation mapping and rotation on the data; and extracting a real part and an imaginary part after constellation mapping and rotation, and combining the real part and the imaginary part to form new data output. According to the method, the memory is saved by optimizing the steps of constellation mapping, constellation rotation and CELL interleaving and adopting a preprocessing and sequence exchange method. In implementation, after CELL interleaving is carried out on input data, constellation mapping is firstly carried out, then rotation is carried out, and finally, rotated real parts and imaginary parts are extracted to form new data. Not only are the validity and correctness of the data ensured, but also the required storage space is greatly reduced through the memory optimization technology.

Description

Technical Field

[0001] The present invention belongs to the field of communication technologies, and more particularly, relates to a cell interleaving method and system for a rotating constellation in the DVB-T2 standard. Background Art

[0002] When the prior art performs what is called mapping and cell interleaving, at the same implementation accuracy, a cell interleaving unit needs to be represented with a data bit width of 32 bits. For storage, the on-chip RAM consumption required for implementing multiple FEC block interleavings is relatively large. Summary of the Invention

[0003] In view of this, the present invention provides a cell interleaving method and system for a rotating constellation in the DVB-T2 standard to solve the above problems.

[0004] To solve the above technical problems, the present invention provides a cell interleaving method for a rotating constellation in the DVB-T2 standard, including:

[0005] Prepare the data to be input, perform serial-to-parallel conversion on it, and sequentially represent it through indexing;

[0006] Perform CELL interleaving on the data after serial-to-parallel conversion, and perform constellation mapping and rotation on it;

[0007] Extract the real part and the imaginary part after constellation mapping and rotation, and combine them to form new data for output.

[0008] As an optional manner, performing constellation mapping and rotation includes:

[0009] Extract the high 8 bits and the low 8 bits of the interleaved data respectively, and convert each 8-bit data into corresponding complex data through constellation mapping according to a preset modulation method;

[0010] Perform multiplication processing on the complex data to adjust the phase and obtain the rotated data;

[0011] Wherein, the multiplication processing includes multiplying each mapped complex point by a rotation factor; the rotated data includes a real part and an imaginary part.

[0012] On the other hand, the present invention also provides a cell interleaving system for a rotating constellation in the DVB-T2 standard, including:

[0013] An input module, which is used to receive input data and perform preliminary preprocessing to ensure that the data format meets the preset requirements;

[0014] An interleaving module, which is used to rearrange the input data according to the preset CELL interleaving rules;

[0015] A constellation mapping module, which is used to convert the interleaved data into a complex form through constellation mapping;

[0016] A constellation rotation module, which is used to perform complex multiplication on the mapped complex data, realizing constellation rotation on the constellation diagram and adjusting the phase position;

[0017] An extraction module, which is used to extract the real part and the imaginary part from the rotated complex data as new data output.

[0018] The beneficial effects of the present invention are as follows:

[0019] The present invention optimizes the steps of constellation mapping, constellation rotation and CELL interleaving, and adopts the methods of preprocessing and swapping the order to save memory. In implementation, after the input data is interleaved by CELL, constellation mapping is first performed, then rotation is performed, and finally the real part and the imaginary part of the rotated data are extracted to form new data. It not only ensures the validity and correctness of the data, but also greatly reduces the required storage space through memory optimization technology. Description of the Drawings

[0020] Figure 1 It is a schematic flowchart of the cell interleaving method for rotating constellations provided by an embodiment of the present invention;

[0021] Figure 2 It is a schematic diagram of the data index structure provided by an embodiment of the present invention;

[0022] Figure 3 It is a schematic diagram of cell interleaving processing provided by an embodiment of the present invention. Detailed Embodiments

[0023] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below in conjunction with the specific embodiments.

[0024] Please refer to Figures 1 - 3 , this embodiment provides a cell interleaving method for rotating constellations in the DVB-T2 standard, including:

[0025] Prepare the data to be input, perform serial-to-parallel conversion on it, and represent it in order through indexing. In this embodiment, please refer to Figure 2 , Figure 2 represents a correspondence between the input data order and the output order after serial-to-parallel conversion, and does not store data. The input data is 8 bits, and the output data is 16 bits. The output data stores one more previous data. For the first output data, the output of the previous bit interleaving module can be controlled to realize that the last data and the first data are output as a group.

[0026] Furthermore, the input data is data after serial-to-parallel conversion, usually 8-bit (i.e., 1 byte). This data has undergone preliminary processing such as encoding and modulation, but has not yet undergone more complex signal processing such as interleaving, mapping, and rotation. The size of the output data is 16-bit, which means that in this embodiment, each output data is larger than the input data. This does not mean that the amount of data will actually increase with each operation, but rather that the output data consists of two parts of the input data. The output 16-bit data represents the new data after interleaving, mapping, and rotation.

[0027] After that, the data after serial-to-parallel conversion is subjected to CELL interleaving, and then constellation mapping and rotation are performed on it; the real part and the imaginary part after constellation mapping and rotation are extracted and combined to form a new data output

[0028] The constellation mapping and rotation in the above process are as Figure 3 , which includes:

[0029] The high 8 bits and the low 8 bits of the interleaved data are respectively extracted, and each 8-bit data is converted into the corresponding complex data through constellation mapping according to the preset modulation method;

[0030] Multiplication processing is performed on the complex data to adjust the phase, and the rotated data is obtained.

[0031] Among them, the multiplication processing includes multiplying each mapped complex data by a rotation factor (complex data); after multiplying two complex data, the result is still a complex data.

[0032] Figure 3 In the process of

[0033]

[0034] Φ represents different rotation phases according to different modulation modes. For example, in QPSK modulation, Φ = 29°, so the obtained rotation factor is: cos(2π*29 / 360)+j*sin(2π*29 / 360) = 0.8746+j*0.4848.

[0035] RE(·) represents taking the real part of the complex data, and IM(·) represents taking the imaginary part of the complex data.

[0036] In this way, through the above solution, the overall logical flow of this embodiment is: input data → CELL interleaving → constellation mapping → constellation rotation → extracting real and imaginary parts → 16-bit output data. The output data not only contains the actual value of the input data, but also has been processed such as constellation mapping and rotation, and contains the real and imaginary parts of the complex number. Through this process, the anti-interference ability of the data can be ensured, the memory usage can be optimized, and at the same time, the processing efficiency and accuracy of the system can be ensured.

[0037] In this embodiment, by preprocessing the data, the requirements for storage and repeated operations are reduced. Through the preprocessing operation of reasonably planning the data processing order, and since the interleaving operation will change the relative positions of the data, by optimizing the data exchange order, the memory occupancy during data exchange can be effectively reduced, thereby achieving the purpose of saving RAM. The storage requirement for intermediate data in the memory is reduced.

[0038] On the other hand, this embodiment also provides a cell interleaving system for rotating constellations in the DVB-T2 standard, including:

[0039] An input module, which is used to receive input data and perform preliminary processing to ensure that the data format meets the preset requirements;

[0040] An interleaving module, which is used to rearrange the input data according to the preset CELL interleaving rules;

[0041] A constellation mapping module, which is used to convert the interleaved data into complex form through constellation mapping;

[0042] A constellation rotation module, which is used to rotate the mapped complex data to adjust the phase position;

[0043] An extraction module, which is used to extract the real and imaginary parts from the rotated complex data as new data output.

[0044] The above is only the preferred embodiment of the present invention. It should be noted that the above preferred embodiment should not be regarded as a limitation of the present invention. The protection scope of the present invention should be subject to the scope defined by the claims. For those of ordinary skill in the art in this technical field, without departing from the spirit and scope of the present invention, several improvements and refinements can also be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A cell interleaving method for rotating constellations in the DVB-T2 standard, characterized in that: include: Prepare the data to be input, convert it into serial and parallel data, and then represent it sequentially through indexes; Perform CELL interleaving on the data after serial-to-parallel conversion, and perform constellation mapping and rotation on it; Extract the real and imaginary parts after constellation mapping and rotation, and combine them to form a new data output.

2. The method for cell interleaving of a rotating constellation in the DVB-T2 standard according to claim 1, characterized in that: The constellation mapping and rotation comprises: Extract the upper 8 bits and the lower 8 bits of the interleaved data respectively, and convert each 8-it data into corresponding complex data through constellation mapping according to the preset modulation method; Performing multiplication processing on the complex data to adjust the phase to obtain rotated data; The multiplication process includes multiplying each mapped complex number by a rotation factor; and the rotated data includes a real part and an imaginary part.

3. A cell interleaving system for rotating constellations in the DVB-T2 standard, characterized in that: include: An input module, which is used to receive input data and perform preliminary processing to ensure that the data format meets preset requirements; An interleaving module, the interleaving module is used to rearrange the input data according to a preset CELL interleaving rule; A constellation mapping module, the constellation mapping module is used to convert the interleaved data into a complex form through constellation mapping; A constellation rotation module, the constellation rotation module is used to rotate the mapped complex data and adjust the phase position; The extraction module is used to extract the real part and the imaginary part from the rotated complex data and output them as new data.

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