CN111818086A - Frame differential compression transmission method suitable for telemetering digital quantity - Google Patents
Frame differential compression transmission method suitable for telemetering digital quantity Download PDFInfo
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- CN111818086A CN111818086A CN202010728614.7A CN202010728614A CN111818086A CN 111818086 A CN111818086 A CN 111818086A CN 202010728614 A CN202010728614 A CN 202010728614A CN 111818086 A CN111818086 A CN 111818086A
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Abstract
The invention provides a frame difference lossless compression transmission method suitable for telemetering digital quantity. The launch task of the carrier rocket needs to launch a large amount of flight parameters to the ground for analysis through telemetering digital quantity, and under the condition that a plurality of sensors are arranged on the rocket, a plurality of telemetering channels are occupied. The channels available for telemetry of digital quantities are limited. The telemetering digital quantity usually adopts equal-length data frames, and the parameter content of the digital quantity belongs to gradual change data. According to the method, difference XOR processing is carried out on the content of a current sending frame of the telemetering digital quantity and the content of a last sending frame according to bytes, and a large amount of redundancy can occur after the difference XOR processing. And then, carrying out Huffman coding compression on the processed data, and sending out the data in a form of fixed frame header with an indefinite frame length. Huffman coding uses standard ballistic telemetry digital values from surface testing as samples. The Huffman code is fixed to the rocket-borne computer before the flight mission, and is used for telemetering digital quantity compression. When the telemetering ground equipment analyzes, the Huffman coding is used for decompressing and carrying out exclusive OR reduction on telemetering digital quantity.
Description
Technical Field
The invention is applied to the field of carrier rocket telemetering digital quantity transmission design, in particular to a lossless compression transmission method of telemetering digital quantity.
Background
With the development of commercial aerospace, the commercial launch task is increasing day by day. The rocket-borne remote measuring equipment not only ensures that the parameters necessary for the launching task are sent back to the ground for analysis, but also has more and more requirements on the analysis parameters of the load by a load side. The launch task of the carrier rocket is different from that of a satellite, the life cycle of the carrier rocket is much shorter than that of the satellite, the bandwidth of a telemetry data channel is limited, and how to send more flight parameters to ground analysis in limited time and limited data bandwidth is particularly important.
The processing speed of the rocket-borne computer is limited, and an efficient and quick compression algorithm is a necessary condition for telemetering data compression application. The error code is a problem that cannot be avoided in the telemetering data transmission, and the decompression process of the compressed data may not be completed if the error code occurs. The compression of the telemetering data is mainly characterized in that the compression speed and the compression ratio are improved, and the error code diffusion in the decompression process caused by telemetering error codes is reduced.
Disclosure of Invention
The technical problem to be solved by the invention is as follows:
the telemetry digital quantity characteristic of the carrier rocket is generally in a fixed frame length; the frame length is generally hundreds to thousands of bytes; the frame content mainly comprises flight working parameters; the data parameters are mostly slowly-varying data; the data parameter type is mostly floating point type; and the data is sent in real time. If a general file compression mode is adopted to carry out real-time compression transmission on each frame of data, the data can be compressed to about 90% of the original data, and the compression rate is low. Because the data is binary data, the data amount of each frame is small, and compressed and encoded information needs to be placed in the compressed data.
The technical solution of the invention is as follows:
carrying out differential processing on the digital quantity of the telemetry frame, namely carrying out exclusive OR processing on the original parameter content of the current frame and the original parameter content of the previous frame according to bytes, compressing the exclusive OR data according to a preset Huffman code, and then sending the compressed data as the current frame, wherein the specific steps are as follows:
And the 2 nd frame of original digital quantity content use the 1 st frame of original digital quantity content as an exclusive-OR object. Compared with the original digital quantity of the 1 st frame, the exclusive-or content actually removes the bits with the same original digital quantity of the 1 st frame and the original digital quantity of the 2 nd frame, and the content of the same bits becomes Bit 0. For floating point type data, slowly varying data, a large amount of Bit0 will appear as the result of such processing. A large number of zero bytes will also appear in the xor-ed content. And then, performing coding compression on the content subjected to the exclusive OR by using a preset Huffman tree. The compressed data is used as the transmission content of the 2 nd frame.
And the 3 rd frame takes the original digital quantity content of the 2 nd frame as an exclusive-OR object. The subsequent steps are the same.
。。。
And the N frame, the original digital quantity of the N frame uses the original digital quantity of the N-1 frame as an exclusive-or object. And then, carrying out coding compression on the result after the XOR by a preset Huffman tree. And taking the compressed data as the transmission content of the Nth frame.
The purpose of the exclusive or is to make 0x00 bytes of redundancy in the content. The purpose of huffman coding is to reduce the total number of bytes occupied by encoding a byte of 0x00 in the content into 1 bit. The huffman tree may be generated during the rocket ground test phase, using the difference result of the digital quantities of the test phase as input samples. The generated Huffman tree is cured in a binary manner to an on-arrow computer for the compression process. The ground parsing uses the same huffman tree for the decompression process. For example, the table of fig. 4 is a huffman code table for a rocket of a certain type. The original byte 0x00 and bit00000000 are re-encoded into bit1, and byte 0x01 and bit00000001 are re-encoded into bit 00111. FIG. 3 is a graph of the frequency of occurrence of a number of bytes of the telemetry array after XOR processing. Encoding the bytes with high frequency will result in fewer bits, reducing the total bit occupancy.
In actual use, the existence of telemetry errors is considered. The maximum value of N is taken as a coefficient K, and because each frame of content except the first frame depends on the result of the previous frame for decompression, if an error code occurs in a certain frame in the middle, the decompression process of the next frame is affected. Here, if the value of K is 5, the process of frame 6 is the same as that of frame 1. The exclusive or object is an all zero byte of equal packet length. The entire compression process is a process that does not repeat the loop 1 st to 5 th frames. The larger the value of K is, the better the compression effect is, the worse the error code diffusion prevention effect is, and vice versa. And setting the maximum value of the K value as K _ MAX (greater than the total frame number of the telemetry digital quantity).
Compared with the prior art, the invention has the advantages that:
1. compared with the common compression process, the method has no real-time re-encoding process, and the encoded information is generated at the beginning, so the compression speed is faster.
2. The frame data can be directly compressed to about 90% of the original data size in a common compression mode, the compression ratio of the method can reach 60% -70%, and the compression ratio effect is better when the more floating point type parameters are used in practice.
3. The value of K can be changed to adjust the compression rate according to the reliability requirement of the telemetering data.
Drawings
And taking actual launching telemetry digital quantity of a rocket of a certain model as statistical reference.
FIG. 1 shows statistics of the frequency of 0x 00-0 xFF bytes in raw telemetry digital data samples.
FIG. 2 shows the frequency statistics of 0x 00-0 xFF bytes in the sample data after the telemetry digital quantity differential processing.
Fig. 3 is a graph showing the variation of K value with compression ratio (size compared to the original number).
FIG. 4 is a Huffman code table of telemetry digital differential processing samples.
Detailed Description
The method for differentially compressing and transmitting the digital telemetry quantity comprises the following steps:
firstly, obtaining a telemetry digital data differential result sample. And in the ground test stage, the digital quantity part in the telemetry channel is separated and stored as a local file A. And traversing each frame of data of the telemetering digital quantity in the file A, removing information such as a frame head, a frame length, a frame tail, verification and the like, and obtaining the unpacking content of each frame. And writing the unpacking content of the 1 st frame into the file B, writing the unpacking content of the 2 nd frame into the file B after the unpacking content of the 1 st frame is subjected to XOR with the unpacking content of the 1 st frame, writing the unpacking content of the 3 rd frame into the file B after the unpacking content of the 3 rd frame is subjected to XOR with the unpacking content of the 2 nd frame, and repeating the steps in the same way to complete the traversal of the telemetering digital quantity frame, wherein the obtained file B is a digital quantity difference result sample.
And secondly, generating a Huffman tree of the differential result samples. In the figure, figure 1 is the statistics of the occurrence frequency of each byte of the original telemetry digital quantity of a rocket of a certain model. FIG. 2 is statistics of occurrence frequency of each byte after difference processing of original telemetry digital quantity of the rocket of the model. And counting the occurrence frequency of each byte by traversing each byte of the B file, taking the counted frequency as input, and performing Huffman coding on the bytes of 0-0 xFF to generate a data structure of a Huffman tree. FIG. 4 is a table output of the Huffman tree. And binary saving the data structure content of the Huffman tree as a file C, and solidifying the file C to the computer on the arrow.
And thirdly, transmitting the digital quantity of the computer on the arrow.
And the arrow computer sends the data of the 1 st frame, and compresses the byte content of the original telemetering digital quantity of the 1 st frame according to the Huffman coding of the file C to generate a new byte array. And packing the new byte groups and adding information such as a frame header, a frame length, a frame tail, verification and the like. To an on-arrow telemetry system.
And when the arrow computer sends the 2 nd frame data, carrying out XOR on the 2 nd frame original telemetering digital quantity and the 1 st frame original telemetering digital quantity, compressing the XOR content according to the Huffman coding of the file C to obtain a new byte array, and packaging the new byte array and adding information such as a frame head, a frame length, a frame tail, verification and the like. To an on-arrow telemetry system.
。。。
And when the Kxn frame data is sent by the computer on the arrow, carrying out exclusive OR on the original telemetering digital quantity of the Kxn frame and the original telemetering digital quantity of the Kxn-1 frame, compressing the exclusive OR content according to the Huffman coding of the file C to obtain a new byte array, and packaging the new byte array and adding information such as a frame head, a frame length, a frame tail, verification and the like. To an on-arrow telemetry system.
And when the Kxn +1 frame data is sent by the computer on the arrow, compressing the byte content of the original telemetry digital quantity of the Kxn +1 frame data according to the Huffman coding of the file C to generate a new byte array. And packing the new byte groups and adding information such as a frame header, a frame length, a frame tail, verification and the like. To an on-arrow telemetry system.
And fourthly, analyzing the ground telemetering data.
The surface equipment parses the 1 st frame telemetry digital quantity. And acquiring the data of the telemetering digital number 1 frame, and removing information such as a frame head, a frame length, a frame tail, verification and the like. And decompressing the unpacked content according to the Huffman tree of the C text. The original 1 st frame raw telemetry digital quantity is obtained.
The surface equipment parses the 1 st frame telemetry digital quantity. And acquiring the data of the telemetering digital number 1 frame, and removing information such as a frame head, a frame length, a frame tail, verification and the like. And decompressing the unpacked content according to the Huffman tree of the file C. And carrying out exclusive OR on the decompressed byte array and the 1 st frame original telemetering digital quantity to obtain a 2 nd frame original telemetering digital quantity.
The surface equipment analyzes the K x n frame telemetry digital quantity. And acquiring the Kxn frame data of the telemetering digital number, and removing information such as a frame head, a frame length, a frame tail, verification and the like. And decompressing the unpacked content according to the Huffman tree of the file C. And XOR the decompressed byte array and the original telemetry digital quantity of the Kxn-1 th frame to obtain the original telemetry digital quantity of the Kxn th frame.
。。。
And the surface equipment analyzes the K × n +1 frame telemetry digital quantity. And acquiring data of Kxn +1 frame of the telemetering digital number, and removing information such as a frame head, a frame length, a frame tail, verification and the like. And decompressing the unpacked content according to the Huffman tree of the file C. And obtaining the K x n +1 frame original telemetry digital quantity.
Claims (3)
1. A frame differential compression transmission method suitable for telemetry digital quantity is characterized in that: and acquiring the telemetering digital quantity of the ground test standard trajectory of the carrier rocket, performing exclusive OR processing on the unpacked content of each frame of telemetering digital quantity after the 2 nd frame and the unpacked content of the telemetering digital quantity of the previous frame, and only unpacking the telemetering digital quantity of the first frame to obtain the sample telemetering digital quantity.
2. The method of claim 1, wherein: carrying out 0x 00-0 xFF occurrence frequency statistics on the sample telemetering digital quantity, carrying out Huffman coding on bytes 0x 00-0 xFF according to the statistical frequency, and solidifying Huffman coding content to an arrow-mounted computer. When the rocket-borne computer sends frame data of the telemetering digital quantity, the telemetering digital quantity of the current frame and the telemetering digital quantity of the previous frame are subjected to exclusive OR processing, the telemetering digital quantity of the first frame is not subjected to exclusive OR processing, then the solidified Huffman code is used for compression, and the compressed content is sent out.
3. The method of claim 2, wherein: and increasing the compression rate of the telemetry digital quantity and the error code prevention system adjustment coefficient K, wherein each Kxn +1(n is 1, 2, 3, 4.) frame telemetry digital quantity is directly compressed by using the solidified Huffman coding without carrying out exclusive OR processing.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113377580A (en) * | 2021-06-28 | 2021-09-10 | 中国西安卫星测控中心 | Method for repairing overflow and error code detection of ground-based telemetry data frame counting |
| CN116450994A (en) * | 2023-06-13 | 2023-07-18 | 东方空间技术(山东)有限公司 | High-frequency telemetry data processing method, computing device and storage medium |
| CN116582889A (en) * | 2023-07-14 | 2023-08-11 | 武汉能钠智能装备技术股份有限公司四川省成都市分公司 | High-throughput data transmission and storage method, electronic equipment and storage medium |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101349979A (en) * | 2008-09-05 | 2009-01-21 | 清华大学 | Method for updating double-magnetic head user data of large scale fault-tolerant magnetic disk array storage system |
| CN101719812A (en) * | 2009-12-15 | 2010-06-02 | 李华 | Method for reducing signal redundancy of wireless sensor network node |
| CN101771497A (en) * | 2008-12-31 | 2010-07-07 | 华为技术有限公司 | Signal transmitting method and device |
| CN102170568A (en) * | 2011-03-11 | 2011-08-31 | 山东大学 | Lossless compression encoder and decoder of hyperspectral remote sensing images |
| CN104144343A (en) * | 2014-07-11 | 2014-11-12 | 东北大学 | Digital image compressing, encrypting and encoding combined method |
| CN105915226A (en) * | 2016-04-27 | 2016-08-31 | 深圳市禾望电气股份有限公司 | Wave recording data processing method and system |
-
2020
- 2020-07-24 CN CN202010728614.7A patent/CN111818086A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101349979A (en) * | 2008-09-05 | 2009-01-21 | 清华大学 | Method for updating double-magnetic head user data of large scale fault-tolerant magnetic disk array storage system |
| CN101771497A (en) * | 2008-12-31 | 2010-07-07 | 华为技术有限公司 | Signal transmitting method and device |
| CN101719812A (en) * | 2009-12-15 | 2010-06-02 | 李华 | Method for reducing signal redundancy of wireless sensor network node |
| CN102170568A (en) * | 2011-03-11 | 2011-08-31 | 山东大学 | Lossless compression encoder and decoder of hyperspectral remote sensing images |
| CN104144343A (en) * | 2014-07-11 | 2014-11-12 | 东北大学 | Digital image compressing, encrypting and encoding combined method |
| CN105915226A (en) * | 2016-04-27 | 2016-08-31 | 深圳市禾望电气股份有限公司 | Wave recording data processing method and system |
Non-Patent Citations (1)
| Title |
|---|
| 梁耀等: "基于帧间差分的随钻测井数据压缩算法", 《数据采集与处理》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113377580A (en) * | 2021-06-28 | 2021-09-10 | 中国西安卫星测控中心 | Method for repairing overflow and error code detection of ground-based telemetry data frame counting |
| CN113377580B (en) * | 2021-06-28 | 2023-06-02 | 中国西安卫星测控中心 | Foundation telemetry data frame counting overflow repairing and error code detecting repairing method |
| CN116450994A (en) * | 2023-06-13 | 2023-07-18 | 东方空间技术(山东)有限公司 | High-frequency telemetry data processing method, computing device and storage medium |
| CN116450994B (en) * | 2023-06-13 | 2023-09-08 | 东方空间技术(山东)有限公司 | High-frequency telemetry data processing method, computing device and storage medium |
| CN116582889A (en) * | 2023-07-14 | 2023-08-11 | 武汉能钠智能装备技术股份有限公司四川省成都市分公司 | High-throughput data transmission and storage method, electronic equipment and storage medium |
| CN116582889B (en) * | 2023-07-14 | 2023-11-21 | 武汉能钠智能装备技术股份有限公司四川省成都市分公司 | High-throughput data transmission and storage method, electronic equipment and storage medium |
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