CN116318357A - Access management method, device, equipment and storage medium of satellite Internet of things - Google Patents

Access management method, device, equipment and storage medium of satellite Internet of things Download PDF

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Publication number
CN116318357A
CN116318357A CN202310299413.3A CN202310299413A CN116318357A CN 116318357 A CN116318357 A CN 116318357A CN 202310299413 A CN202310299413 A CN 202310299413A CN 116318357 A CN116318357 A CN 116318357A
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China
Prior art keywords
decoding
equipment
accessed
request information
things
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CN202310299413.3A
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Chinese (zh)
Inventor
焦健
苏诗莹
杨涛
王野
吴绍华
张钦宇
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Shenzhen Graduate School Harbin Institute of Technology
Peng Cheng Laboratory
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Shenzhen Graduate School Harbin Institute of Technology
Peng Cheng Laboratory
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Priority to CN202310299413.3A priority Critical patent/CN116318357A/en
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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
    • H04B7/18519—Operations control, administration or maintenance
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/004—Arrangements for detecting or preventing errors in the information received by using forward error control
    • H04L1/0045—Arrangements at the receiver end
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0048—Allocation of pilot signals, i.e. of signals known to the receiver
    • 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
    • H04L67/01—Protocols
    • H04L67/12—Protocols specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W28/00—Network traffic management; Network resource management
    • H04W28/02—Traffic management, e.g. flow control or congestion control
    • H04W28/06—Optimizing the usage of the radio link, e.g. header compression, information sizing, discarding information
    • H04W28/065—Optimizing the usage of the radio link, e.g. header compression, information sizing, discarding information using assembly or disassembly of packets
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Abstract

The application discloses an access management method, device, equipment and storage medium of a satellite Internet of things, wherein the method comprises the following steps: classifying the equipment to be accessed based on timeliness requirements and reliability requirements of service types, and determining class groups of each equipment to be accessed; sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and the grade group; and decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed. According to the method and the device, the equipment to be accessed is classified according to the timeliness requirement and the reliability requirement of the service types, so that the satellite sequentially receives the request information which is sent according to the groups and compiled through the preset codebook, the timeliness requirement and the reliability requirement of different service types are met, the capacity of the satellite access equipment is enlarged through the preset codebook, the problem that a user selects pilot frequency to collide is solved, and the timeliness and the reliability of the data information transmission of the equipment to be accessed are improved.

Description

Access management method, device, equipment and storage medium of satellite Internet of things
Technical Field
The present application relates to the field of internet of things, and in particular, to an access management method, device, equipment and storage medium for a satellite internet of things.
Background
The satellite Internet of things can not be influenced by terrains and ground objects, so that the means of covering each corner of the world can be fully utilized, and the satellite Internet of things can provide services for places without a ground network.
The equipment without ground network coverage is accessed to the satellite Internet of things, so that the equipment can transmit information by using the satellite. In order to ensure that the same pilot frequency cannot appear, the number of the used pilot frequencies exceeds the set number, pilot frequency conflict is selected by user equipment, and a common technical means is to solve the problem of user conflict when a large number of user equipment access satellites by using a multi-time slot access scheme. Although the success rate of acquiring the data information sent by the user equipment by the satellite can be improved by using the multi-slot access scheme, that is, the success rate of accessing the satellite by the user equipment is improved, the timeliness of the data information is reduced.
Disclosure of Invention
The main purpose of the application is to provide an access management method, device, equipment and storage medium of the satellite Internet of things, which aim to solve the technical problem that the timeliness of transmitting data information of user equipment is reduced when the problem of pilot frequency conflict caused by user equipment selection is solved by utilizing a multi-time slot access scheme in the prior art.
In order to achieve the above object, the present application provides an access management method for a satellite internet of things, where the access management method for the satellite internet of things includes:
classifying the equipment to be accessed based on timeliness requirements and reliability requirements of service types, and determining class groups of each equipment to be accessed;
sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and the grade group;
and decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed.
Optionally, the step of decoding the request information and feeding back a decoding result to the corresponding device to be accessed includes:
screening out an external code from the request information;
based on the external code, determining the number of the devices using the same pilot frequency when the devices to be accessed send request information;
if the number of the devices is larger than the preset decoding number, selecting decoding devices with the same decoding number from conflict devices selecting the same pilot frequency;
and decoding the request information of the decoding equipment and feeding back a decoding result to the decoding equipment.
Optionally, before the step of decoding the request information of the decoding device and feeding back the decoding result to the decoding device, the method further includes:
Determining the transmission quality of a channel used when the decoding equipment transmits the request information;
the step of decoding the request information of the decoding device and feeding back a decoding result to the decoding device comprises the following steps:
and based on the transmission quality, sequentially performing interference elimination and decoding on the request information, and feeding back a decoding result to the decoding equipment.
Optionally, the step of sequentially performing interference cancellation and decoding on the request information based on the transmission quality and feeding back a decoding result to the decoding device includes:
determining a decoding order of the decoding device based on the transmission quality;
based on the decoding sequence, carrying out independent interference elimination on the request information in sequence, and independently decoding an internal code in the request information;
if the internal code fails to be decoded independently, marking the corresponding decoding equipment as failure equipment;
continuously and jointly decoding the failure equipment and a decoding equipment set of which the decoding sequence is behind the failure equipment;
and feeding back the first decoding result of the independent decoding and the second decoding result of the continuous joint decoding to the corresponding decoding equipment.
Optionally, if the number of devices is greater than a preset decoding number, before the step of selecting the decoding device equal to the decoding number from the conflict devices for selecting the same pilot frequency, the method further includes:
acquiring access data of access history equipment, and calculating average information history age and access history failure rate of each history equipment;
adjusting the maximum number of multiplexing of the pilot frequency supporting the equipment to be accessed based on the average information historical age and the access historical failure rate;
the maximum number is defined as a coding number.
Optionally, the step of sequentially receiving the request information sent by the device to be accessed based on the preset codebook and the level packet includes:
if the equipment to be accessed is the first group with the highest grade or the second group with the lowest grade in the grade groups, receiving request information sent by the equipment to be accessed based on a preset codebook and a preset independent serial scheme;
and if the equipment to be accessed is not the first packet or the second packet, sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and a preset unloading transmission scheme.
Optionally, after the step of decoding the request information and feeding back a decoding result to the corresponding device to be accessed, the method further includes:
calculating average information current age and current failure rate of access of the equipment to be accessed in the current transmission process;
and verifying timeliness and reliability of access management of the equipment to be accessed based on the average information current age and the access current failure rate.
The application also provides an access management device of satellite internet of things, the access management device of satellite internet of things includes:
the grading module is used for grading the equipment to be accessed based on the timeliness requirement and the reliability requirement of the service type, and determining the grade group of each equipment to be accessed;
the receiving module is used for sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and the grade packet;
and the decoding module is used for decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed.
The application also provides access management equipment of the satellite Internet of things, wherein the access management equipment of the satellite Internet of things is entity node equipment, and the access management equipment of the satellite Internet of things comprises: the method comprises a memory, a processor and a program of the access management method of the satellite internet of things, wherein the program of the access management method of the satellite internet of things is stored in the memory and can run on the processor, and the steps of the access management method of the satellite internet of things can be realized when the program of the access management method of the satellite internet of things is executed by the processor.
The application also provides a storage medium, on which a program for implementing the above-mentioned access management method of the satellite internet of things is stored, and when the program for implementing the above-mentioned access management method of the satellite internet of things is executed by a processor, the steps of the above-mentioned access management method of the satellite internet of things are implemented.
Compared with the prior art that when a multi-time slot access scheme is utilized to solve the problem of pilot frequency conflict caused by user equipment selection, the timeliness of data information transmission of the user equipment is reduced, in the method, the equipment to be accessed is classified based on the timeliness requirement and the reliability requirement of service types, and the class group of each equipment to be accessed is determined; sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and the grade group; and decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed. According to the method and the device, the equipment to be accessed is classified according to the timeliness requirement and the reliability requirement of the service type, so that the equipment to be accessed determines respective request information according to the class group and the preset codebook, the satellite sequentially receives the request information sent by the equipment to be accessed, finally decodes the request information, and feeds back decoding results to the corresponding equipment to be accessed, namely, in the method and the device to be accessed is classified according to the timeliness requirement and the reliability requirement of the service type, so that the satellite sequentially receives the request information compiled by the preset codebook and sent according to the group, the timeliness requirement and the reliability requirement of different service types are met, the capacity of the satellite access equipment is enlarged by the preset codebook, the problem that a user selects pilot frequency to collide is solved, and the timeliness and the reliability of the data information transmitted by the equipment to be accessed are improved.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description, serve to explain the principles of the application.
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the description of the embodiments or the prior art will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.
Fig. 1 is a schematic flow chart of a first embodiment of an access management method of the satellite internet of things in the present application;
fig. 2 is a schematic flow chart of random access of a user equipment to a satellite in the access management method of the satellite internet of things of the application;
FIG. 3 is a schematic diagram of a device architecture of a hardware runtime environment according to an embodiment of the present application;
fig. 4 is a schematic diagram of a model of an access management system of the satellite internet of things of the present application;
fig. 5 is a schematic flow chart of a second embodiment of an access management method of the satellite internet of things of the present application;
fig. 6 is a schematic diagram of an independent serial scheme in the access management method of the satellite internet of things of the present application;
Fig. 7 is a schematic diagram of an unloading transmission scheme in an access management method of the satellite internet of things in the application;
fig. 8 is a schematic diagram of an access failure probability formula of a user l in MCUs and TSMUs in a third embodiment of an access management method of the satellite internet of things in the present application;
fig. 9 is a schematic diagram of a calculation formula of an access failure probability of a user i in TTMUs in a third embodiment of an access management method of the satellite internet of things in the present application;
fig. 10 is an nth embodiment of an access management method for satellite internet of things according to the present application 3 Schematic diagram of an average information age calculation formula of a frame.
The realization, functional characteristics and advantages of the present application will be further described with reference to the embodiments, referring to the attached drawings.
Detailed Description
It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.
In a first embodiment of the access management method of the satellite internet of things, referring to fig. 1, the access management method of the satellite internet of things includes:
step S10, classifying the equipment to be accessed based on the timeliness requirement and the reliability requirement of the service type, and determining the class group of each equipment to be accessed;
Step S20, request information sent by the equipment to be accessed based on a preset codebook and the grade group is received in sequence;
and step S30, decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed.
The present embodiment aims at: when the problem of pilot frequency conflict is solved, timeliness and reliability of data information transmission of the equipment to be accessed are improved.
In this embodiment, it should be noted that, the access management method of the satellite internet of things may be applied to an access management device of the satellite internet of things, where the access management device of the satellite internet of things belongs to an access management device of the satellite internet of things, and the access management device of the satellite internet of things belongs to an access management system of the satellite internet of things.
In this embodiment, referring to fig. 4, an access pipe system of the satellite internet of things includes a satellite and a user equipment (to be accessed), wherein the satellite may be a low earth orbit high throughput satellite.
In this embodiment, the service types may be MCC (Mission Critical Communications, mission critical communication) service and emtc (bulk Machine-communication) service, and the devices to be accessed are classified into MCC type mission critical user devices and emtc type user devices, that is, MCUs (mccues, MCC service user devices with high requirements for timeliness and reliability) according to the requirements of MCC service and emtc service for timeliness, specifically, mctc type user devices may be further classified into TSMUs (Timeliness Sensitive mMTC UEs, emtc service user devices with high requirements for timeliness and reliability) and TTMUs (Timeliness Tolerant mMTC UEs, emtc service user devices with low requirements for timeliness and reliability) according to the requirements for timeliness and reliability of the service types.
The reliability may be a probability of success of the device to be accessed to access the satellite.
In this embodiment, the request information of the device to be accessed is sequentially sent to the satellite according to the packets, wherein the packet grade is that the grade of the MCUs is higher than the grade of the TSMUs, and the grade of the TSMUs is higher than the grade of the TTMUs, so that the request information with high requirement on timeliness is preferentially transmitted to the satellite, and timeliness when the user equipment accesses the satellite is improved.
In this embodiment, the capacity of the satellite access device can be enlarged by using the preset codebook to encode the request information, and the pilots associated with the codebook can be multiplexed, that is, the plurality of devices to be accessed can use the same pilot to transmit the request information, and whether the devices to be accessed selecting the same pilot can collide or not is judged according to the codebook, if so, the request information of the devices to be accessed with the preset decoding number is decoded, so that the access success rate of the devices to be accessed is improved, that is, the reliability of the devices to be accessed is improved, and the problem that the users select the pilot to collide is solved.
The method comprises the following specific steps:
step S10, classifying the equipment to be accessed based on the timeliness requirement and the reliability requirement of the service type, and determining the class group of each equipment to be accessed;
The MCC service type devices to be accessed need to be accessed to the satellite at a specified time point, so that the MCC service corresponds to the devices to be accessed MCUs with the highest grade.
Wherein TSMUs and TTMUs can access satellites within acceptable access delays, and TSMUs are more sensitive to aging than TTMUs, and TSMUs are less highly reliable than TTMUs, i.e., TSMUs are more reliable than TTMUs, so TSMUs is rated higher than TTMUs, and the traffic types corresponding to TSMUs and TTMUs are mctc traffic types, so TSMUs is rated lower than MCUs.
Wherein the MCC service can be an access delay requirement with the magnitude of 30ms and 10 -5 The reliability requirements of the magnitude, such as public safety service, intelligent transportation system service and the like, are high, so that the timeliness requirements on information are high, and the requirements on the reliability are high; some mMTC traffic can be with an access latency requirement on the order of 100ms and 10 -4 To 10 -3 The requirement of magnitude reliability, high sensitivity to time-dependent information and higherReliability requirements of (a) such as medical monitoring services, voice, video interactive game services, etc.; while some mMTC traffic may be with latency requirements on the order of greater than 100ms, and 10 -2 To 10 -1 The order of reliability requirements, the timeliness requirements for the information are not high, and the reliability requirements are relatively low, such as non-mission critical user plane push-to-talk voice services, etc.
In this embodiment, according to the timeliness requirement and the reliability requirement of the service type, the devices to be accessed may be divided into n groups, each leased class is determined, and each class group of the devices to be accessed is determined, so that the time for the devices to be accessed to access the satellite can meet the corresponding timeliness.
Step S20, request information sent by the equipment to be accessed based on a preset codebook and the grade group is received in sequence;
in this embodiment, a set of request information to be transmitted by each batch of devices to be accessed may be defined as one transmission frame, and when the request information is transmitted, the transmission frame is divided into a plurality of subframes according to the groups of the devices to be accessed, that is, if the devices to be accessed are divided into n groups, one transmission frame is also divided into n subframes.
In this embodiment, the satellite only receives the request information transmitted by the device to be accessed in each subframe at a time, so that the device to be accessed with high time efficiency requirement can be accessed first, so that the time efficiency of transmitting the request information by the device to be accessed is improved according to the type of the device to be accessed, that is, the sequence of accessing the device to be accessed is determined according to the time efficiency of the request information, so that the time efficiency requirement of transmitting the request information by each device to be accessed can be satisfied.
In this embodiment, before the device to be accessed sends the request information, a pilot frequency needs to be randomly selected from a preset pilot frequency set, where each pilot frequency signal corresponds to a unique orthogonal codebook of order T.
It should be noted that, the preset codebook at least includes a concatenation code of an outer code and an inner code, where the outer code may be BCH coding, and the inner code may be LDPC coding, so as to achieve the purpose that each pilot frequency may be used for multiplexing by T user equipments.
Specifically, the step of sequentially receiving the request information sent by the device to be accessed based on the preset codebook and the level packet includes:
step S21, if the equipment to be accessed is the first group with the highest grade or the second group with the lowest grade in the grade groups, receiving request information sent by the equipment to be accessed based on a preset codebook and a preset independent serial scheme;
step S22, if the device to be accessed is not the first packet or the second packet, sequentially receiving request information sent by the device to be accessed based on a preset codebook and a preset unloading transmission scheme.
In this embodiment, the scheme of transmitting the device to be accessed to the satellite can be divided into an independent serial scheme and an offload transmission scheme.
Wherein, referring to fig. 6, one transmission frame is divided into three subframes, i.e., N 1 、N 2 And N 3 The independent serial scheme can be that, in N 1 Complete transmission of MCUs type to-be-accessed device in subframe, and in N 2 Complete transmission of TSMUs type to-be-accessed device in subframe, and the method comprises the following steps of N 3 And completely transmitting the TTMUs type to-be-accessed device in the subframe.
Wherein, referring to fig. 7, one transmission frame is divided into three subframes, i.e., N 1 、N 2 And N 3 The offload transmission scheme may be at N 2 In the subframe, the device to be accessed of the TSMUs type is transmitted, and the device to be accessed of the TTMUs type is also transmitted.
It should be noted that the independent serial scheme may be an offload transmission scheme, where TSMUs is N 2 After randomly selecting the pilot, if at N 2 The pilot frequency in (a) is remained, a part of the equipment to be accessed is selected from TTMUs according to the channel quality of the equipment to be accessed, and N is used 2 The subframe transmits request information to improve the timeliness of TTMUs, and the time is an unloading transmission scheme; if at N 2 If there is no pilot left in the transmission scheme, determining that the offloading transmission scheme is an independent serial scheme.
In the present embodiment, first, the independent strings are executedRow scheme: at N 1 In the method, access resources are only used by the MCUs, so that strict success access probability and access aging requirements of the MCUs are ensured. In this subframe, the scheduling MCUs select resource blocks, i.e. from the pilot set
Figure SMS_1
Is selected randomly. In subframe N 1 At the end, HTS receiving terminal pair is at N 1 Performs decoding on the received information, and then in N 2 Optionally continuing to execute the independent serial scheme or switching to an offload transmission scheme: if at N 2 Only the TSMUs are transmitted in N 3 When only TTMUs transmits information, the whole scheme is an independent serial scheme.
In the present embodiment, if the selection is made at N 2 Optionally, CO-UTMA scheme: then at N 2 In (1) dividing pilot frequency resources into
Figure SMS_2
And->
Figure SMS_3
Two parts, D 1 Part of the resources are only used by TSMUs, D 2 Part of the resources are only available to TTMUs. At the beginning of the subframe, users in TSMUs are scheduled to go from D 1 Is selected and at the same time scheduling +.>
Figure SMS_4
TTMUs slave D 2 Pilot resources are selected. In subframe N 2 To offload traffic of a portion of TTMUs to mitigate subframe N 3 And to some extent, to improve the access timeliness of TTMUs. In subframe N 2 At the end, HTS receiving terminal pair is at N 2 Performs decoding on all the information received in (a) and if the scheduled TTMUs is successfully decoded, performs decoding on the information received in (b) in subframe N 3 Keep silent in subframe N 3 And then access is carried out.
In the present embodiment, at N 3 In only subframe N 2 Random access by the remaining non-scheduled TTMUs, i.e. scheduling the users Device slave pilot set
Figure SMS_5
Is selected randomly. In subframe N 3 At the end, HTS receiving terminal pair is at N 3 Performs decoding of all information received in the (c).
Note that N 1 Only MCU is accessed, N 3 Only TTMU is accessed; n (N) 2 Either independent serial or offload transmission schemes.
And step S30, decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed.
In this embodiment, the external code of the request information needs to be interpreted first to determine the number of devices to be accessed that select the same pilot frequency, determine that there is no conflict between the devices to be accessed that select the pilot frequency, or interpret the internal code of the request information after resolving the conflict; and if each pilot frequency can be multiplexed by the T devices to be accessed, recovering the request information of the T devices from the conflicting devices to be accessed.
In the present embodiment, referring to fig. 2, one transmission frame is divided into three subframes, i.e., N 1 、N 2 And N 3 At N 1 In the method, when a time slot starts, the MCUs randomly select one pilot frequency from a pilot frequency set to obtain a corresponding unique codebook for encoding. After encoding, the selected pilot and data information is transmitted to the satellite, wherein the request information includes the selected pilot, the encoded data information, and the pilot index. The satellite estimates the channel response based on the received pilot signals, performs decoding recovery information at the end of the time slot, and recovers collisions up to T-th order for each pilot using a codebook. If the satellite decoding is successful, an Acknowledgement (ACK) message is sent to the user, and if the decoding is failed, a negative message (Negative Acknowledgement, NACK) is sent to the user.
In this embodiment, referring to fig. 2, at the beginning of a slot, TSMUs and a portion of TTMUs are scheduled to randomly select one pilot from their respective pilot sets in N2, resulting in a corresponding unique codebook for encoding. And similarly, after the selection is finished, the selected pilot frequency and uplink data information are sent to the satellite. The satellite estimates a channel response based on the received pilot signal at the end of the slot, and performs decoding recovery information. And if the decoding of the user is successful, sending ACK to the user, and if the decoding is failed, sending NACK to the user.
In this embodiment, referring to fig. 3, in N3, random access is performed in the sub-frame N2 access failure and the remaining non-accessed TTMUs. Similarly, when the N3 subframe starts, the user which is not successfully accessed in the TTMUs randomly selects one pilot frequency from the pilot frequency set to obtain a corresponding unique codebook for encoding. And similarly, after the selection is finished, the selected pilot frequency and uplink data information are sent to the satellite. The satellite estimates a channel response based on the received pilot signal at the end of the slot, and performs decoding recovery information. And if the decoding of the user is successful, sending ACK to the user, and if the decoding is failed, sending NACK to the user.
Specifically, the step of decoding the request information and feeding back a decoding result to the corresponding device to be accessed includes:
step S31, screening out the outer code from the request information;
step S32, based on the external code, determining the number of the devices using the same pilot frequency when the devices to be accessed send request information;
step S33, if the number of the devices is larger than the preset decoding number, selecting decoding devices with the same decoding number from conflict devices for selecting the same pilot frequency;
step S34, the request information of the decoding device is decoded, and the decoding result is fed back to the decoding device.
In this embodiment, by interpreting the outer code in the request information, it is determined how many devices to be accessed are selected by one pilot, that is, the number of devices to be accessed that select the same pilot is determined according to the outer code, and whether the devices to be accessed have a conflict is determined by a preset decoding number, if the number of devices is greater than the decoding number, that is, the devices to be accessed have a conflict, the decoding device with the decoding number is selected from the devices, and the decoding device is decoded, so that each pilot can be multiplexed for the decoding number of devices to be accessed, that is, each pilot can be decoded for the request information of the decoding number of devices to be accessed.
It should be noted that if the number of devices is greater than the number of decoding devices, the decoding devices may be selected randomly or according to the quality of the channel, so as to improve the flexibility of management.
In this embodiment, whether the decoding result is a decoding failure or a decoding success, the decoding result is fed back to the corresponding device to be accessed, so that the device to be accessed performs the next operation according to the decoding result.
Specifically, before the step of decoding the request information of the decoding device and feeding back the decoding result to the decoding device, the method further includes:
step S35, determining the transmission quality of the used channel when the decoding equipment sends the request information;
in this embodiment, the channel used may be a shadow-rice fading channel to avoid scattering and shadowing effects caused by obstructions in actual wireless communications.
The step of decoding the request information of the decoding device and feeding back a decoding result to the decoding device comprises the following steps:
and step A10, based on the transmission quality, sequentially performing interference elimination and decoding on the request information, and feeding back a decoding result to the decoding equipment.
In this embodiment, before the inner code in the request message is interpreted, an interference cancellation operation is performed on the request message to be interpreted, so as to reduce the signal and channel noise of other devices and interference cancellation residual interference signals.
Specifically, the step of sequentially performing interference cancellation and decoding on the request information based on the transmission quality and feeding back a decoding result to the decoding device includes:
step A11, determining the decoding sequence of the decoding equipment based on the transmission quality;
step A21, based on the decoding sequence, carrying out independent interference elimination on the request information in sequence, and independently decoding an internal code in the request information;
step A13, if the internal code fails to be decoded independently, marking the corresponding decoding equipment as failure equipment;
step A14, carrying out continuous joint decoding on the failure equipment and the decoding equipment set of which the decoding sequence is behind the failure equipment;
and step A15, feeding back the first decoding result of the independent decoding and the second decoding result of the continuous joint decoding to the corresponding decoding equipment.
In this embodiment, the decoding order of the decoding apparatus may be determined according to the transmission quality, and the decoding apparatus may be interference-canceled according to the decoding order, and may be individually decoded immediately after the interference cancellation.
In this embodiment, whether the decoding is successful is determined by the signal-to-interference-and-noise ratio of the device to be accessed, and if the signal-to-interference-and-noise ratio of the first device to be accessed is smaller than the decoding threshold, decoding failure will result. And after decoding fails, starting from the l devices to be accessed, and performing continuous joint decoding on the first device to be accessed and the subsequent users, thereby recovering the data in the request information.
Compared with the prior art that when a multi-time slot access scheme is utilized to solve the problem of pilot frequency conflict caused by user equipment selection, the timeliness of data information transmission of the user equipment is reduced, in the method, the equipment to be accessed is classified based on the timeliness requirement and the reliability requirement of service types, and the class group of each equipment to be accessed is determined; sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and the grade group; and decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed. According to the method and the device, the equipment to be accessed is classified according to the timeliness requirement and the reliability requirement of the service type, so that the equipment to be accessed determines respective request information according to the class group and the preset codebook, the satellite sequentially receives the request information sent by the equipment to be accessed, finally decodes the request information, and feeds back decoding results to the corresponding equipment to be accessed, namely, in the method and the device to be accessed is classified according to the timeliness requirement and the reliability requirement of the service type, so that the satellite sequentially receives the request information compiled by the preset codebook and sent according to the group, the timeliness requirement and the reliability requirement of different service types are met, the capacity of the satellite access equipment is enlarged by the preset codebook, the problem that a user selects pilot frequency to collide is solved, and the timeliness and the reliability of the data information transmitted by the equipment to be accessed are improved.
Further, based on the foregoing embodiments of the present application, another embodiment of the present application is provided, in this embodiment, referring to fig. 5, if the number of devices is greater than a preset decoding number, then before the step of selecting, from conflicting devices that select the same pilot, a decoding device equal to the decoding number, the method further includes:
step S01, obtaining access data of access history equipment, and calculating average information history age and access history failure rate of each history equipment;
step S02, adjusting the maximum number of multiplexing of the pilot frequency supporting the equipment to be accessed based on the average information historical age and the access historical failure rate;
step S03, defining the maximum number as a decoding number.
In the embodiment, by acquiring access data of accessed historical equipment, calculating average historical age and access historical failure rate of each historical equipment; the influence of pilot frequency distribution proportion on average information history age of MCUs, TSMUs or TTMUs is analyzed when different devices to be accessed are accessed, the sensitivity of the average information history age of the devices to be accessed in each group to the change of the pilot frequency distribution proportion is judged, when the insensitivity of the change of the pilot frequency distribution proportion is determined, the parameter value of the pilot frequency distribution proportion is determined, and according to the parameter value, the maximum number of the same pilot frequency to be selected by the devices to be accessed is determined.
In this embodiment, the decoding number is optimally adjusted by researching the influence of the pilot frequency allocation proportion and the scheduling proportion on the scheme performance, so as to adjust the capacity of the satellite access equipment to be accessed.
Further, based on the foregoing embodiments of the present application, another embodiment of the present application is provided, in this embodiment, after the step of decoding the request information and feeding back a decoding result to the corresponding device to be accessed, the method further includes:
step B10, calculating average information current age and current failure rate of access of the equipment to be accessed in the current transmission process;
and step B20, verifying timeliness and reliability of access management of the equipment to be accessed based on the average information current age and the access current failure rate.
In this embodiment, since the device to be accessed selects the pilot frequency
Figure SMS_6
The post access failure may be caused by three conditions:
wherein the first case is that user/alone uses pilot frequency
Figure SMS_7
But signal-to-interference-and-noise ratio->
Figure SMS_8
Less than the decoding threshold->
Figure SMS_9
Resulting in decoding failure.
The second case is that user l shares pilot with user p
Figure SMS_10
. If the channel condition of user l is better than user p, if user l fails to access, user l fails to decode, and continuous joint decoding with user p fails, i.e. signal-to-interference-and-noise ratio- >
Figure SMS_11
Less than the decoding threshold->
Figure SMS_12
And->
Figure SMS_13
Less than the decoding threshold->
Figure SMS_14
The method comprises the steps of carrying out a first treatment on the surface of the If the channel condition of user l is inferior to user p, user l fails to decode, i.e. the signal-to-interference-plus-noise ratio +.>
Figure SMS_15
Less than the decoding threshold->
Figure SMS_16
。
Wherein the third case is that user l collides, i.e. user l shares pilot frequency with two or more users
Figure SMS_17
If the channel condition of user l is not the worst, user l fails to decode and fails to decode continuously in combination with the following user, i.e. S/N +.>
Figure SMS_18
Less than the decoding threshold->
Figure SMS_19
And->
Figure SMS_20
Less than the decoding threshold->
Figure SMS_21
The method comprises the steps of carrying out a first treatment on the surface of the If the channel condition of user l is the worst, user l fails to decode, i.e. the signal-to-interference-plus-noise ratio +.>
Figure SMS_22
Less than the decoding threshold->
Figure SMS_23
。
In the present embodiment, when the access failure probability of the device to be accessed l is calculated, it may be calculated according to the above three cases.
The calculation formula of the first case is as follows:
Figure SMS_24
；
wherein, the calculation formula of the second case is:
Figure SMS_25
；
the calculation formula of the third case is as follows:
Figure SMS_26
；
where K is the active user, L is the total number of pilots in the pilot set,
Figure SMS_27
；
Figure SMS_28
for transmitting power, +.>
Figure SMS_29
For the average power of the multipath component, +.>
Figure SMS_30
Power for white gaussian noise, +.>
Figure SMS_31
Is Nakagami-m parameter, < ->
Figure SMS_32
-average power of LoS, R is inner code rate, < > >
Figure SMS_33
Is the residual interference power coefficient of the SIC.
In this embodiment, the calculation formula of the access failure probability of the user i in MCUs and TSMUs refers to fig. 8, the calculation formula of the access failure probability of the user i in TTMUs refers to fig. 9, and the theoretical result of the access failure rate of each service can be calculated through the calculation formula of the access failure probability of the user i in MCUs and TSMUs and the calculation formula of the access failure probability of the user i in TTMUs.
In this embodiment, the average information current age of the device to be accessed in the current transmission process is calculated by using a formula of the average information age. Wherein, the calculation formula is:
Figure SMS_34
（1）；
Figure SMS_35
（2）；
in this embodiment, equation (1) is the N 1 Calculation formula of average information age of frame, formula (2) is Nth 2 The calculation formula of the average information age of the frame, referring to the formula in fig. 10 is nth 3 The calculation formula of the average information age of the frame can calculate the theoretical result of the average information age of each service based on the formula (1), the formula (2) and the formula in fig. 10.
In this embodiment, the reliability of the access management of the device to be accessed is verified by comparing the theoretical result of the access failure rate with the access failure rate in the actual application process, and the timeliness of the verification on the access management of the device to be accessed is verified by comparing the theoretical result of the average information age with the average information age of the actual application.
Referring to fig. 3, fig. 3 is a schematic diagram of a device mechanism of a hardware running environment according to an embodiment of the present application.
As shown in fig. 3, the access management device of the satellite internet of things may include: a processor 1001, such as a CPU, memory 1005, and a communication bus 1002. Wherein a communication bus 1002 is used to enable connected communication between the processor 1001 and a memory 1005. The memory 1005 may be a high-speed RAM memory or a stable memory (non-volatile memory), such as a disk memory. The memory 1005 may also optionally be a storage device separate from the processor 1001 described above.
Optionally, the access management device of the satellite internet of things may further include a rectangular user interface, a network interface, a camera, an RF (Radio Frequency) circuit, a sensor, an audio circuit, a WiFi module, and so on. The rectangular user interface may include a Display screen (Display), an input sub-module such as a Keyboard (Keyboard), and the optional rectangular user interface may also include a standard wired interface, a wireless interface. The network interface may optionally include a standard wired interface, a wireless interface (e.g., WI-FI interface).
It will be appreciated by those skilled in the art that the access management device mechanism of the satellite internet of things shown in fig. 3 does not constitute a limitation of the access management device of the satellite internet of things, and may include more or less components than illustrated, or may combine certain components, or a different arrangement of components.
As shown in fig. 3, an operating system, a network communication module, and an access management program for the satellite internet of things may be included in the memory 1005 as one type of storage medium. The operating system is a program for managing and controlling hardware and software resources of the access management device of the satellite Internet of things, and supports the operation of the access management program of the satellite Internet of things and other software and programs. The network communication module is used for realizing communication among components in the memory 1005 and communication among other hardware and software in an access management system of the satellite internet of things.
In the access management device of the satellite internet of things shown in fig. 3, the processor 1001 is configured to execute an access management program of the satellite internet of things stored in the memory 1005, to implement the steps of any one of the above access management methods of the satellite internet of things.
The specific implementation manner of the access management device of the satellite internet of things is basically the same as each embodiment of the access management method of the satellite internet of things, and is not repeated here.
The application also provides an access management device of satellite internet of things, the access management device of satellite internet of things includes:
the grading module is used for grading the equipment to be accessed based on the timeliness requirement and the reliability requirement of the service type, and determining the grade group of each equipment to be accessed;
The receiving module is used for sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and the grade packet;
and the decoding module is used for decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed.
Optionally, the coding module includes:
the screening module is used for screening out the external codes from the request information;
the first selection module is used for determining the number of the devices using the same pilot frequency when the devices to be accessed send request information based on the external code;
the second selecting module is used for selecting decoding equipment with the same decoding number from conflict equipment for selecting the same pilot frequency if the equipment number is larger than the preset decoding number;
and the decoding submodule is used for decoding the request information of the decoding equipment and feeding back a decoding result to the decoding equipment.
Optionally, the access management device of the satellite internet of things further includes:
the determining module is used for determining the transmission quality of the used channel when the decoding equipment sends the request information;
the pair of coding submodules includes:
and the feedback module is used for sequentially carrying out interference elimination and decoding on the request information based on the transmission quality and feeding back a decoding result to the decoding equipment.
Optionally, the feedback module includes:
a determining submodule, configured to determine a decoding order of the decoding apparatus based on the transmission quality;
the internal code interpretation module is used for sequentially carrying out independent interference elimination on the request information based on the decoding sequence and independently interpreting the internal codes in the request information;
the marking module is used for marking the corresponding decoding equipment as failure equipment if the independent decoding of the internal code fails;
the joint decoding module is used for carrying out continuous joint decoding on the failure equipment and the decoding equipment set with the decoding sequence behind the failure equipment;
and the feedback module is used for feeding back the first decoding result of the independent decoding and the second decoding result of the continuous joint decoding to the corresponding decoding equipment.
Optionally, the feedback module includes:
the first calculation module is used for acquiring the access data of the access history equipment and calculating the average information history age and the access history failure rate of each history equipment;
the adjustment module is used for adjusting the maximum number of multiplexing of the pilot frequency supporting the equipment to be accessed based on the average information historical age and the access historical failure rate;
And the fixed module is used for defining the maximum number as the decoding number.
Optionally, the receiving module includes:
the first receiving sub-module is used for receiving request information sent by the equipment to be accessed based on a preset codebook and a preset independent serial scheme if the equipment to be accessed is the first packet with the highest grade or the second packet with the lowest grade in the grade packets;
and the second receiving sub-module is used for sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and a preset unloading transmission scheme if the equipment to be accessed is not the first packet or the second packet.
Optionally, the access management of the satellite internet of things further includes:
the second calculation module is used for calculating the average information current age and the current access failure rate of the equipment to be accessed in the current transmission process;
and the verification module is used for verifying the timeliness and the reliability of the access management of the equipment to be accessed based on the average information current age and the access current failure rate.
The specific implementation manner of the access management device of the satellite internet of things is basically the same as each embodiment of the access management method of the satellite internet of things, and is not repeated here.
The embodiment of the application provides a storage medium, and the storage medium stores one or more programs, and the one or more programs can be further executed by one or more processors to implement the steps of the method for managing access of the satellite internet of things.
The specific implementation manner of the storage medium is basically the same as the above embodiments of the access management method of the satellite internet of things, and is not repeated here.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising a" or "comprising an" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
The foregoing embodiment numbers of the present invention are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments.
From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment method may be implemented by means of software plus a necessary general hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. ROM/RAM, magnetic disk, optical disk) comprising instructions for causing a terminal device (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to perform the method of the embodiments of the present invention.
The foregoing description of the preferred embodiments of the present invention should not be taken as limiting the scope of the invention, but rather should be understood to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following description and drawings.

Claims (10)

1. The access management method of the satellite Internet of things is characterized by comprising the following steps of:
Classifying the equipment to be accessed based on timeliness requirements and reliability requirements of service types, and determining class groups of each equipment to be accessed;
sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and the grade group;
and decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed.
2. The method for managing access to the satellite internet of things according to claim 1, wherein the step of decoding the request information and feeding back a decoding result to the corresponding device to be accessed comprises:
screening out an external code from the request information;
based on the external code, determining the number of the devices using the same pilot frequency when the devices to be accessed send request information;
if the number of the devices is larger than the preset decoding number, selecting decoding devices with the same decoding number from conflict devices selecting the same pilot frequency;
and decoding the request information of the decoding equipment and feeding back a decoding result to the decoding equipment.
3. The method for managing access to the internet of things of satellite according to claim 2, wherein before the step of decoding the request information of the decoding device and feeding back the decoding result to the decoding device, the method further comprises:
Determining the transmission quality of a channel used when the decoding equipment transmits the request information;
the step of decoding the request information of the decoding device and feeding back a decoding result to the decoding device comprises the following steps:
and based on the transmission quality, sequentially performing interference elimination and decoding on the request information, and feeding back a decoding result to the decoding equipment.
4. The method for managing access to the internet of things of satellite according to claim 3, wherein the step of sequentially performing interference cancellation and decoding on the request information based on the transmission quality and feeding back a decoding result to the decoding device comprises:
determining a decoding order of the decoding device based on the transmission quality;
based on the decoding sequence, carrying out independent interference elimination on the request information in sequence, and independently decoding an internal code in the request information;
if the internal code fails to be decoded independently, marking the corresponding decoding equipment as failure equipment;
continuously and jointly decoding the failure equipment and a decoding equipment set of which the decoding sequence is behind the failure equipment;
and feeding back the first decoding result of the independent decoding and the second decoding result of the continuous joint decoding to the corresponding decoding equipment.
5. The method for managing access to the internet of things of satellite according to claim 2, wherein if the number of devices is greater than a preset decoding number, before the step of selecting a decoding device equal to the decoding number from among conflicting devices that select the same pilot, the method further comprises:
acquiring access data of access history equipment, and calculating average information history age and access history failure rate of each history equipment;
adjusting the maximum number of multiplexing of the pilot frequency supporting the equipment to be accessed based on the average information historical age and the access historical failure rate;
the maximum number is defined as a coding number.
6. The method for managing access to the satellite internet of things according to claim 1, wherein the step of sequentially receiving the request information sent by the device to be accessed based on the preset codebook and the level packet comprises:
if the equipment to be accessed is the first group with the highest grade or the second group with the lowest grade in the grade groups, receiving request information sent by the equipment to be accessed based on a preset codebook and a preset independent serial scheme;
and if the equipment to be accessed is not the first packet or the second packet, sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and a preset unloading transmission scheme.
7. The method for managing access to the satellite internet of things according to claim 1, wherein after the step of decoding the request information and feeding back the decoding result to the corresponding device to be accessed, the method further comprises:
calculating average information current age and current failure rate of access of the equipment to be accessed in the current transmission process;
and verifying timeliness and reliability of access management of the equipment to be accessed based on the average information current age and the access current failure rate.
8. The utility model provides an access management device of satellite thing networking which characterized in that, the access management device of satellite thing networking includes:
the grading module is used for grading the equipment to be accessed based on the timeliness requirement and the reliability requirement of the service type, and determining the grade group of each equipment to be accessed;
the receiving module is used for sequentially receiving request information sent by the equipment to be accessed based on a preset codebook and the grade packet;
and the decoding module is used for decoding the request information and feeding back a decoding result to the corresponding equipment to be accessed.
9. The access management device of the satellite Internet of things is characterized by comprising: a memory, a processor and a program stored on the memory for implementing an access management method for the satellite internet of things,
The memory is used for storing a program for realizing an access management method of the satellite Internet of things;
the processor is configured to execute a program for implementing the method for access management of the satellite internet of things, so as to implement the steps of the method for access management of the satellite internet of things according to any one of claims 1 to 7.
10. A storage medium, wherein a program for implementing an access management method of the satellite internet of things is stored on the storage medium, and the program for implementing the access management method of the satellite internet of things is executed by a processor to implement the steps of the access management method of the satellite internet of things as set forth in any one of claims 1 to 7.
CN202310299413.3A 2023-03-24 2023-03-24 Access management method, device, equipment and storage medium of satellite Internet of things Pending CN116318357A (en)

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