CN112367108A - Dynamic cache optimization method for satellite real-time monitoring system - Google Patents
Dynamic cache optimization method for satellite real-time monitoring system Download PDFInfo
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- CN112367108A CN112367108A CN202011042020.7A CN202011042020A CN112367108A CN 112367108 A CN112367108 A CN 112367108A CN 202011042020 A CN202011042020 A CN 202011042020A CN 112367108 A CN112367108 A CN 112367108A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
- H04B7/15—Active relay systems
- H04B7/185—Space-based or airborne stations; Stations for satellite systems
- H04B7/1851—Systems using a satellite or space-based relay
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/14—Relay systems
- H04B7/15—Active relay systems
- H04B7/185—Space-based or airborne stations; Stations for satellite systems
- H04B7/1851—Systems using a satellite or space-based relay
- H04B7/18513—Transmission in a satellite or space-based system
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L67/00—Network arrangements or protocols for supporting network services or applications
- H04L67/50—Network services
- H04L67/56—Provisioning of proxy services
- H04L67/568—Storing data temporarily at an intermediate stage, e.g. caching
Abstract
The invention relates to a cache dynamic optimization method for a satellite real-time monitoring system, and belongs to the technical field of satellite real-time monitoring. The method fully utilizes the characteristic of low actual measurement and control coverage rate of the medium and low orbit satellite, performs dynamic cache optimization according to the measurement and control plan and the reference parameters, and can effectively improve the memory utilization rate of the multi-satellite on-orbit real-time monitoring and alarming system, reduce the system operation load and improve the system operation reliability and performance under the condition that the number of satellites is increased sharply.
Description
Technical Field
The invention relates to a cache dynamic optimization method for a satellite real-time monitoring system, and belongs to the technical field of satellite real-time monitoring.
Background
At present, in order to realize the efficient real-time interpretation of telemetry data, a multi-satellite on-orbit real-time monitoring alarm system of each satellite monitoring center needs to pre-load all telemetry parameter information of on-orbit satellites in a cache, wherein the information comprises attributes such as an ID, a Chinese name, an English name, an affiliated subsystem, an affiliated single machine and the like, and rule knowledge for interpretation and diagnosis. With the increase of transmission bandwidth and satellite capacity, the number of telemetry parameters of a single satellite exceeds 1 ten thousand, and under the condition that the number of satellites is increased sharply, cache resources occupied by information required by centralized diagnosis of hundreds of satellites are increasingly huge, so that optimization design is required.
Most of the existing cache optimization technologies focus on frequency statistics of access behaviors of a large number of end users, analyze parts with high hit rate in a data set according to a certain time period, use the parts as 'hot' data, and optimize caches of a server according to predicted frequency distribution results. From the aspect of time dimension, the cold and hot states of the data are essentially influenced by retrieval requests, are random and discrete, and are not suitable for the caching service of satellite on-orbit real-time monitoring, because the measurement and control data reception of the satellite has unique characteristics:
different from the sustainable measurement and control of geosynchronous orbit satellites, most of the existing satellites in China are medium and low orbit satellites, the orbit height is mostly concentrated between 200-1200km, the orbit period is about 90-100 minutes, about more than ten circles of operation are performed every day, the visible circle number of a single measurement and control station is 2-4 circles, the visible time of each circle is about several minutes to more than ten minutes, generally, for each medium and low orbit satellite, the measurement and control coverage rate of an S frequency band measurement and control network distributed in the territory of China can measure and control 6-8 circles every day, and the measurement and control coverage rate is about 8%. However, tracking and measurement are often required to be carried out at least 2 times each of rail ascending and rail descending every day, and the measurement and control coverage rate is required to be about 50% -90%, so that the characteristics of high requirement and low actual measurement and control coverage rate exist.
In actual service, measurement and control plans of all medium and low orbit satellites can be obtained by planning and calculating the satellite orbit position and the ground station tracking capability, although the measurement and control plans are not accurate enough, the measurement and control plans can be advanced or delayed for several minutes, the tracking duration is accurate, and the situations that the measurement and control plans are temporarily cancelled due to a fault or the number of turns is temporarily increased due to emergency treatment due to the fault exist.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the method has the advantages of low memory overhead, high resource utilization rate and the like, can effectively improve the memory utilization rate of the satellite real-time monitoring system, reduce the system operation load and improve the system operation reliability and performance when a large number of satellites need to be monitored in parallel.
A dynamic cache optimization method for a satellite real-time monitoring system comprises the following steps:
(1) after a satellite real-time monitoring system is initially started, traversing and judging whether the satellite is a medium-low orbit satellite or not, if not, loading a diagnosis rule of the satellite and parameter information related in the diagnosis rule, and starting and continuously carrying out real-time interpretation diagnosis until the satellite real-time monitoring system is closed; if the satellite is a medium-low orbit satellite, reading the latest upcoming circle in the measurement and control plan of the satellite, and marking the tracking initial time of the latest circle as TPlan 0The end time is TPlan 1And judging whether the current time reaches TPlan 0-10min, if reached, automatically loading the satellite diagnosisCutting off the rule and the parameter information, and if the rule and the parameter information are not reached, not loading;
(2) the satellite real-time monitoring system monitors the reference parameters of the medium-low orbit satellite in real time if the reference parameters are in [ T ]Plan 0-10min,TPlan 1+10min]Within a time range and within all time periods t within the time range, the reference parameter frame number of the satellite received by the satellite real-time monitoring system does not exceed a preset threshold value, the marked measurement and control plan of the latest circle is temporarily cancelled, and the diagnosis rule and the parameter information of the satellite loaded in the cache of the satellite real-time monitoring system are eliminated; the time period t is a set value, such as 5s or 10 s;
if at [ TPlan 0-10min,TPlan 1+10min]In a time range and within any time period t in the time range, if the reference parameter frame number of the satellite received by the satellite real-time monitoring system exceeds a preset threshold value, the marked measurement and control plan of the latest circle is an actual measurement and control circle, then real-time interpretation diagnosis is carried out according to the diagnosis rule and parameter information of the satellite loaded in the cache of the satellite real-time monitoring system, when the frame number of the reference parameter received by the satellite real-time monitoring system within the time period t does not increase, the real-time interpretation diagnosis is finished, and the diagnosis rule and parameter information of the satellite loaded in the cache of the satellite real-time monitoring system are eliminated;
if in [ - ∞, TPlan 0]Or [ TPlan 1，+∞]Within a time range and within any time period t within the time range, if the reference parameter frame number of the satellite received by the satellite real-time monitoring system exceeds a preset threshold, the marked measurement and control plan of the latest circle is to temporarily increase the measurement and control circle, the diagnosis rule and the parameter information of the satellite are automatically loaded, then real-time interpretation diagnosis is carried out according to the diagnosis rule and the parameter information of the satellite loaded in the cache of the satellite real-time monitoring system, and when the frame number of the reference parameter received by the satellite real-time monitoring system within the time period t is not increased, the real-time interpretation diagnosis is ended, and the diagnosis rule and the parameter information of the satellite loaded in the cache of the satellite real-time monitoring system are cleared;
the reference parameters of the medium-low orbit satellite refer to the telemetry parameters with the shortest download period and the highest frequency in the telemetry parameters of the satellite, and are used for judging whether data reception is continuous or not.
(3) And (3) repeating the steps (1) and (2) until the satellite real-time monitoring system is closed.
Compared with the prior art, the invention has the advantages that:
the method makes full use of the characteristic of low actual measurement and control coverage rate of the medium and low orbit satellite, performs dynamic cache optimization according to the measurement and control plan and the reference parameters, and can effectively improve the memory utilization rate of the multi-satellite on-orbit real-time monitoring and alarming system, reduce the system operation load and improve the system operation reliability and performance under the condition that the number of satellites is increased sharply.
Drawings
Fig. 1 is a flow chart of rule and telemetry parameter cache dynamic loading destruction.
Detailed Description
The invention is further illustrated by the following figures and examples.
As shown in fig. 1, a dynamic cache optimization method for a satellite real-time monitoring system includes the following steps:
(1) selecting a telemetering parameter with the shortest download period and the highest frequency as a reference parameter of each medium-low orbit satellite, and configuring the telemetering parameter in a database; generally, a frame count downloaded by each frame of telemetering data is selected as a reference parameter;
(2) two Key-Value type Map caches are created for each satellite:
the tmMap is used for caching satellite telemetry parameters, takes a telemetry parameter ID as Key, takes telemetry parameter information TmBean as Value, and takes the TmBean as a structured object, wherein the TmBean comprises fields such as a telemetry parameter ID, a telemetry parameter serial number, a telemetry parameter code number, a telemetry parameter name and a data type;
the rule map is used for caching satellite diagnosis rules, the rule ID is used as Key, the rule information RuleBean is used as Value, the RuleBean is used as a structured object and comprises fields such as the rule ID, interpretation types, rule contents, whether to enable the rule or not, creation time and the like;
(3) when the system is initially started, judging the satellite orbit type, if the satellite is not a medium-low orbit satellite, starting a satellite information initialization method, namely loading all telemetering parameter information of the satellite from a database to a telemetering parameter cache, loading a diagnosis rule to a diagnosis rule cache (hereinafter referred to as satellite information initialization), starting to receive telemetering data, and diagnosing each telemetering parameter;
(4) establishing and starting a timing reading thread of a medium and low orbit satellite measurement and control plan, reading measurement and control plan information in the future 24 hours every half hour, and synchronously updating the measurement and control plan information to a cache;
(5) if the satellite type is a medium and low orbit satellite, a time window judgment thread is created and started, and when a measurement and control plan window ([ T0 plan-10 min, T1 plan +10min ]) of the satellite is found to be hit, the method comprises the following steps: when the current time is greater than T0 plan-10 min, starting satellite information initialization, and setting a satellite loading indication flag to true after the satellite information initialization is completed;
(6) reading the reference parameter information of the medium and low orbit satellite, creating and starting a reference parameter change monitoring thread, and monitoring the reference parameter change condition of each satellite in real time. When the updating times of the reference parameters reach 30 times within 60 seconds, judging whether the satellite loading indication flag is true, if true, considering the circle as an actual measurement and control circle in a plan, and starting to diagnose; otherwise, the satellite is considered to start the tracking of a newly increased circle outside the plan, the initialization of satellite information is started, the satellite loading indication flag is set to true, and the diagnosis is started;
(7) when the time window judging thread finds that the satellite measurement and control plan window is expired and no actual measurement and control data exists in the circle, the plan circle is judged to be temporarily cancelled, satellite information caching and destroying are started, namely a tmMap.
(8) As the observation and control visibility time of each circle of the medium and low orbit satellite in the territory of China is about several minutes to dozens of minutes, the judgment threshold value for the end of the observation and control tracking can be set to be 5 minutes, namely when the reference parameter change monitoring thread finds that the satellite reference parameters continue for 5 minutes and no data is received, the satellite information caching and destruction is started, and the satellite loading indication flag is set to be false.
Examples
The satellite real-time monitoring system is initially started, the satellite A is determined to be a medium-low orbit satellite in a traversing mode, the upcoming latest circle in the measurement and control plan of the satellite A is read, and the tracking initial time of the latest circle is marked to be TPlan 010:00, end time TPlan 1The results of the satellite real-time monitoring system monitoring the reference parameter value of the satellite A in the time range from 9:00 to 13:01 in real time are shown in the table 1, and the diagnostic rule and the parameter information of the satellite are automatically loaded before 9: 50;
according to table 1 and whether the reference parameter frame number of the satellite received by the satellite real-time monitoring system in all the time periods t of the time range is greater than a preset threshold value 3 within 5s, the judgment result is shown in table 2;
according to table 2, the measurement and control plan of the satellite a on the day has two time intervals, which are 10: 00-10: 10 and 13: 00-13: 10 respectively. When the current time is 09:00:00, the reference parameter is not received, namely the frame number of the reference parameter of the satellite received by the satellite real-time monitoring system in 5s does not exceed 3, and the diagnosis rule and the parameter information of the satellite are not loaded at the moment; when the current time is 09:50:00 as time goes on, T is judged to be reached at the timePlan 0Automatically loading the diagnostic rule and the parameter information of the satellite in 10min to 10:05, and clearing the diagnostic rule and the parameter information of the satellite loaded in the cache of the real-time satellite monitoring system when the frame number of the reference parameters received by the real-time satellite monitoring system in 5s is not increased; when the current time is 11:30:04, the reference parameter frame number of the satellite received by the satellite real-time monitoring system in the period of t being 5s is 5, and the condition that the reference parameter frame number of the satellite received by the satellite real-time monitoring system in the period of t being 5s exceeds 3 is met, so that the diagnosis rule and the parameter information of the satellite are loaded, and when the current time is 11:40:05, the frame number of the reference parameter received by the satellite real-time monitoring system in the period of 5s is not increased, the diagnosis rule and the parameter information of the satellite loaded in the cache of the satellite real-time monitoring system are cleared; when the current time is 12:50:00And judges that T is reached at this timePlan 0Automatically loading the diagnostic rule and parameter information of the satellite in 10min, and judging that T is reached at the moment when the time is 13:20:00Plan 1And +10min, clearing the diagnosis rule and parameter information of the satellite loaded in the cache of the satellite real-time monitoring system.
TABLE 1 reference parameter values for satellite A
| Time of day | Reference parameter value |
| 09:00:00 | - |
| 09:00:01 | - |
| 09:00:02 | - |
| …… | - |
| 10:00:00 | 1000 |
| 10:00:01 | 1001 |
| 10:00:02 | 1002 |
| 10:00:03 | 1003 |
| …… | …… |
| 10:10:00 | 1600 |
| 10:10:01 | - |
| 10:10:02 | - |
| …… | - |
| 11:30:00 | 2140 |
| 11:30:01 | 2141 |
| 11:30:02 | 2142 |
| 11:30:03 | 2143 |
| 11:30:04 | 2144 |
| …… | …… |
| 11:40:00 | 2200 |
| 11:40:01 | - |
| 11:40:02 | - |
| …… | - |
| 13:00:00 | - |
| 13:00:01 | - |
| …… | - |
In the table, "-" indicates no numerical value.
TABLE 2 judgment results
Claims (7)
1. A dynamic cache optimization method for a satellite real-time monitoring system is characterized by comprising the following steps: the method aims at a satellite which is a medium and low orbit satellite, and comprises the following steps:
(1) after a satellite real-time monitoring system is initially started, reading the latest upcoming circle in the measurement and control plan of the medium-low orbit satellite, and marking the tracking initial time of the latest circle as TPlan 0The end time is TPlan 1And judging whether the current time reaches TPlan 0-10min, if the diagnosis rule and the parameter information of the medium and low orbit satellite are reached, automatically loading the diagnosis rule and the parameter information of the medium and low orbit satellite, and if the diagnosis rule and the parameter information are not reached, not loading the diagnosis rule and the parameter information;
(2) the satellite real-time monitoring system monitors the reference parameters of the medium and low orbit satellite in real time;
if at [ TPlan 0-10min,TPlan 1+10min]Within a time range and within all time periods t within the time range, the reference parameter frame number of the medium and low orbit satellite received by the satellite real-time monitoring system does not exceed a preset threshold value, the marked measurement and control plan of the latest circle is temporarily cancelled, the diagnosis rule and the parameter information of the satellite loaded in the cache of the satellite real-time monitoring system are cleared, and the dynamic optimization of the cache of the satellite real-time monitoring system is completed;
if at [ TPlan 0-10min,TPlan 1+10min]In a time range and within any time period t in the time range, if the reference parameter frame number of the medium and low orbit satellite received by the satellite real-time monitoring system exceeds a preset threshold value, the marked measurement and control plan of the latest circle is an actual measurement and control circle, then real-time interpretation diagnosis is carried out according to the diagnosis rule and parameter information of the satellite loaded in the cache of the satellite real-time monitoring system, when the frame number of the reference parameter received by the satellite real-time monitoring system within the time period t does not increase, the real-time interpretation diagnosis is finished, the diagnosis rule and parameter information of the medium and low orbit satellite loaded in the cache of the satellite real-time monitoring system are removed, and the dynamic optimization of the cache of the satellite real-time monitoring system is finished;
if in [ - ∞, TPlan 0]Or [ TPlan 1，+∞]Within a time range and within any time period t within the time range, if the reference parameter frame number of the medium and low orbit satellite received by the satellite real-time monitoring system exceeds a preset threshold value, the marked measurement and control plan of the latest circle is to temporarily increase the measurement and control circle, then real-time interpretation diagnosis is carried out according to the diagnosis rule and parameter information of the medium and low orbit satellite loaded in the cache of the satellite real-time monitoring system, and when the frame number of the reference parameter received by the satellite real-time monitoring system within the time period t does not increase, the real-time interpretation diagnosis is finished, the diagnosis rule and parameter information of the medium and low orbit satellite loaded in the cache of the satellite real-time monitoring system are eliminated, and the dynamic optimization of the cache of the satellite real-time monitoring system is completed;
(3) and (3) repeating the steps (1) and (2) until the satellite real-time monitoring system is closed.
2. The dynamic cache optimization method for the satellite real-time monitoring system according to claim 1, wherein the dynamic cache optimization method comprises the following steps: the reference parameters of the medium-low orbit satellite refer to the telemetry parameters with the shortest download period and the highest frequency in the telemetry parameters of the satellite, and are used for judging whether data reception is continuous or not.
3. The dynamic cache optimization method for the satellite real-time monitoring system according to claim 2, wherein the dynamic cache optimization method comprises the following steps: and selecting the frame count downloaded by each frame of telemetering data of the medium and low orbit satellite as a reference parameter.
4. The dynamic cache optimization method for the satellite real-time monitoring system according to claim 1, wherein the dynamic cache optimization method comprises the following steps: the time period t is a set value.
5. The dynamic cache optimization method for the satellite real-time monitoring system according to claim 4, wherein the dynamic cache optimization method comprises the following steps: the time period t is 5s or 10 s.
6. A dynamic cache optimization method for a satellite real-time monitoring system is characterized by comprising the following steps: the method is directed to satellites that are not low and medium orbit satellites, and comprises the following steps:
and initially starting the satellite real-time monitoring system, directly loading the diagnosis rule of the satellite and the parameter information related in the diagnosis rule, starting and continuously carrying out real-time interpretation diagnosis until the satellite real-time monitoring system is closed, and finishing the dynamic optimization of the cache of the satellite real-time monitoring system.
7. The dynamic cache optimization method for the satellite real-time monitoring system according to claim 1, wherein the dynamic cache optimization method comprises the following steps: creating two Key-Value type Map caches for each medium and low orbit satellite, namely a tmMap cache and a rulMap cache respectively;
the tmMap is used for caching satellite telemetry parameters, takes a telemetry parameter ID as Key, takes telemetry parameter information TmBean as Value, and takes the TmBean as a structured object, wherein the TmBean comprises fields such as a telemetry parameter ID, a telemetry parameter serial number, a telemetry parameter code number, a telemetry parameter name and a data type;
the rule map is used for caching satellite diagnosis rules, the rule ID is used as Key, the rule information RuleBean is used as Value, the RuleBean is used as a structured object and comprises fields such as the rule ID, interpretation type, rule content, whether to enable and create time and the like.
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