阅读说明：本技术 Tdma卫星通信系统长时不确定登录方法、装置及存储介质 (Long-time uncertain login method and device for TDMA satellite communication system and storage medium ) 是由 靳年鑫 于 2020-12-28 设计创作，主要内容包括：本发明提供一种TDMA卫星通信系统长时不确定登录方法、装置及存储介质,方法,包括步骤：在登录时隙原始长度基础上增加预定时间长度作为重新确定的登录时隙长度；在原始登录起始时刻基础上提前预定时间间隔作为修正的登录起始时刻；以重新确定的登录时隙长度作为中心站的规划登录时隙范围,使远端站以修正的登录起始时刻作为其时隙登录计划时刻,在规划登录时隙范围内进行登录,远端站和中心站均处于星状卫星TDMA系统网络的卫星覆盖范围。有效解决卫星终端在无GPS或GPS位置信息不准确情况下的登录问题,提高登录效率,防止干扰其他卫星终端业务。(The invention provides a long-time uncertain login method, a device and a storage medium for a TDMA satellite communication system, wherein the method comprises the following steps: increasing a preset time length on the basis of the original length of the login time slot as a redetermined login time slot length; taking a preset time interval in advance as a corrected login starting time on the basis of the original login starting time; and taking the re-determined login time slot length as a planned login time slot range of the central station, taking the corrected login starting time as the time slot login plan time of the remote station, and logging in the planned login time slot range, wherein the remote station and the central station are both in the satellite coverage range of the star-shaped satellite TDMA system network. The problem of login of the satellite terminal under the condition that no GPS or inaccurate GPS position information exists is effectively solved, login efficiency is improved, and other satellite terminal services are prevented from being interfered.)

A long-time uncertain login method for a TDMA satellite communication system is characterized by comprising the following steps:

increasing a preset time length on the basis of the original length of the login time slot as a redetermined login time slot length;

a predetermined time interval is advanced as a modified login start time on the basis of the original login start time.

2. The method for long time indeterminate entry into a TDMA satellite communication system as claimed in claim 1, further comprising the steps of: and taking the re-determined login time slot length as a planned login time slot range of the central station, and taking the corrected login starting time as the time slot login plan time of the remote station to log in the planned login time slot range, wherein the remote station and the central station are both in the satellite coverage range of the star-shaped satellite TDMA system network.

3. The method for long term indeterminate entry into a TDMA satellite communication system as claimed in claim 2 wherein said predetermined length of time is set in accordance with the distance between the closest point to the satellite on the earth's surface and the satellite on the earth's surface, and the distance between the farthest point to the satellite on the earth's surface, said closest point being the point within the coverage of the satellite and the farthest point from the satellite on the earth's surface.

4. The method for long time indeterminate entry into a TDMA satellite communication system as claimed in claim 3, wherein said predetermined time length is ≦ 2 x (Dm-H)/c, wherein (Dm-H)/c is the propagation delay offset between said closest point and said farthest point, Dm is the distance between said farthest point and the satellite, and Dm = ((R + H)²-R²)^1/2H is the distance between the nearest point and the satellite, c is the speed of light 30 km/s, and R is the radius of the earth.

5. The method for long term indeterminate entry into a TDMA satellite communication system as claimed in claim 2 wherein said predetermined time interval is based on a hub to satellite link delay T_fAnd the transmission delay T from the satellite to the remote station_bThe setting is performed.

6. The method for long time indeterminate entry in a TDMA satellite communication system as claimed in claim 5, wherein said predetermined time interval is ≦ 2 (T)_f+ H/c), where H is the distance between the closest point to the satellite, the closest point being the point on the surface of the earth closest to the satellite, and c is the speed of light 30 km/s.

A long-term uncertain logging device for a TDMA satellite communication system, comprising:

the time slot range module is used for increasing a preset time length on the basis of the original length of the login time slot to be used as the length of the newly determined login time slot;

and the initial time module is used for taking a preset time interval in advance as a corrected login initial time on the basis of the original login initial time.

8. The apparatus for long uncertainty entry in a TDMA satellite communication system according to claim 7, wherein:

the time slot range module is used for enabling the re-determined login time slot length to serve as a planned login time slot range of the central station;

the starting time module is used for using the corrected login starting time as the time slot login plan time of the remote station so that the remote station can log in according to the time slot login plan time within the planned login time slot range;

the remote station and the central station are both within the satellite coverage of a star satellite TDMA system network.

9. The apparatus for long uncertainty entry in a TDMA satellite communication system according to claim 7, wherein:

the preset time length is determined according to the distance between the nearest point and the satellite and the distance between the farthest point and the satellite, wherein the nearest point is the point on the earth surface closest to the satellite, and the farthest point is the point on the earth surface farthest from the satellite in the coverage range of the satellite;

the predetermined time interval is based on the link delay T from the central station to the satellite_fAnd the transmission delay T from the satellite to the remote station_bAnd (4) determining.

10. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, controls an apparatus in which the storage medium is located to perform a long-term uncertain entry method of a TDMA satellite communication system according to any of claims 1-6.

Technical Field

The invention relates to satellite communication technology, in particular to a long-time uncertain login method, a long-time uncertain login device and a long-time uncertain login storage medium of a TDMA satellite communication system.

Background

As shown in fig. 1, in a star-like satellite TDMA system network, a central station is a device with one transmission and multiple receptions, wherein forward transmission is in a TDM manner, and backward reception is in a TDMA manner; the remote station is a transceiver in which forward reception is FDMA and reverse transmission is TDMA. The central station is responsible for service convergence on the forward link, provides time-sharing access of the return link and is responsible for time slot allocation of the whole network equipment. The remote station side is used as a user service access device and sends the service to the central station according to the time slot plan.

In the system, the central station broadcasts the registration time slot regularly for the remote station to register. Under the condition that the remote station has the GPS position, the remote station can correct the local time according to the position information of the remote station and combining the satellite and the main station position information, and then can correctly use the login time slot to perform login processing. However, when the remote station has no GPS or the GPS location information is inaccurate, the remote station cannot correct the local time normally, or has a certain correction deviation. In this case, the remote station cannot use the login timeslot accurately, and if the login timeslot is forcibly used, interference may be caused to other service timeslots, and in a serious case, the remote station may be offline and service may be interrupted. There is a need for an efficient method to log onto a central station when the remote station does not have a GPS or the GPS location information is inaccurate.

Disclosure of Invention

The invention mainly aims at the defects of the related prior art, provides a long-time uncertain login method, a device and a storage medium for a TDMA satellite communication system, effectively solves the login problem of a satellite terminal under the condition of no GPS or inaccurate GPS position information, improves the login efficiency and prevents other satellite terminal services from being interfered.

In order to achieve the above object, the present invention employs the following techniques:

the long-time uncertain login method of the TDMA satellite communication system comprises the following steps:

increasing a preset time length on the basis of the original length of the login time slot as a redetermined login time slot length;

taking a preset time interval in advance as a corrected login starting time on the basis of the original login starting time;

and taking the re-determined login time slot length as a planned login time slot range of the central station, and taking the corrected login starting time as the time slot login plan time of the remote station to log in the planned login time slot range, wherein the remote station and the central station are both in the satellite coverage range of the star-shaped satellite TDMA system network.

Further, the method can be used for preparing a novel materialThe preset time length is set according to the distance between the closest point and the satellite and the distance between the farthest point and the satellite, the closest point is the point on the earth surface closest to the satellite, and the farthest point is the point on the earth surface farthest from the satellite in the coverage range of the satellite. The predetermined time length is less than or equal to 2 x (Dm-H)/c, wherein (Dm-H)/c is the transmission delay deviation between the nearest point and the farthest point, Dm is the distance between the farthest point and the satellite, and Dm = ((R + H)²-R²)^1/2H is the distance between the nearest point and the satellite, c is the speed of light 30 km/s, and R is the radius of the earth.

Further, the predetermined time interval is based on the link delay T from the central station to the satellite_fAnd the transmission delay T from the satellite to the remote station_bThe setting is performed. The predetermined time interval is less than or equal to 2 (T)_f+ H/c), where H is the distance between the closest point to the satellite, the closest point being the point on the surface of the earth closest to the satellite, and c is the speed of light 30 km/s.

The uncertain login device of TDMA satellite communication system long time includes:

the time slot range module is used for increasing a preset time length on the basis of the original length of the login time slot to be used as the length of the newly determined login time slot;

and the initial time module is used for taking a preset time interval in advance as a corrected login initial time on the basis of the original login initial time.

Further, the time slot range module is configured to enable the re-determined login time slot length to serve as a planned login time slot range of the central station;

the starting time module is used for using the corrected login starting time as the time slot login plan time of the remote station so that the remote station can log in according to the time slot login plan time within the planned login time slot range;

the remote station and the central station are both within the satellite coverage of a star satellite TDMA system network.

A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, controls an apparatus in which the storage medium is located to perform the TDMA satellite communication system long-term uncertain registration method.

The invention has the beneficial effects that:

1. the login problem of the satellite terminal under the condition of no GPS or inaccurate GPS position information is effectively solved, the login efficiency is improved, and other satellite terminal services are prevented from being interfered;

2. in the login mode, the length of the newly determined login time slot is set to be long enough, so that the login signaling sent by the remote station can be prevented from causing interference to other stations, any point in the satellite coverage area can be logged in according to the time slot plan and can fall within the login time slot range planned by the central station, and the data transmission of other stations cannot be influenced by shifting to the adjacent time slot.

Drawings

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

FIG. 1 is a satellite network topology diagram of a star satellite TDMA system network.

Fig. 2 is a schematic diagram of satellite positions according to an embodiment of the present application.

Fig. 3 shows the original login slot range planned by the central station according to the embodiment of the present application.

Fig. 4 shows the re-determined login slot length according to an embodiment of the present application.

FIG. 5 is a time slot diagram of the remote station with corrected login time in the original login time slot range according to the embodiment of the present application

Fig. 6 is a time slot diagram after remote station registration time correction of the re-determined registration time slot length according to the embodiment of the present application.

Fig. 7 is a block diagram of an apparatus according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings, but the described embodiments of the present invention are a part of the embodiments of the present invention, not all of the embodiments of the present invention.

Example one

The embodiment provides a long-time uncertain login method for a TDMA satellite communication system.

Fig. 2 shows a diagram of location information of a central station, a remote station, and a satellite.

Wherein, the central station position is A point. Assuming that the longitude of the satellite is x, the longitude of the satellite coverage on the earth is: x-81.3 DEG to x +81.3 DEG, with a coverage dimension in the range of 81.3 DEG N to 81.3 DEG S, at any point in this range a remote station may be present.

Normal remote station login scenario:

before the remote station initiates login, the forward link needs to be time synchronized first, and after synchronization is completed, the central station and the remote station realize coarse synchronization. In this case, the absolute time of the remote station is earlier than the central station by a whole transmission delay, i.e. the sum of the transmission delays from the central station to the satellite and from the satellite to the remote station.

If the remote station is to log in at the login time indicated by the central station, the remote station is to log in at the login time T₀And (6) correcting. Suppose the link delay from the central station to the satellite is T_fThe time delay of the satellite to the remote station is T_bIf the corrected login time slot time of the remote station is T₀-2*(T_f+T_b) As shown in FIGS. 3 to 4.

Transmission delay T under the condition that the remote station has no GPS or the GPS position information is inaccurate_bCannot be obtained correctly. In order to prevent the login signaling sent by the remote station from causing interference to other stations, the length of the login time slot needs to be set to be long enough to ensure that the remote station can log in at any point of the satellite coverage and can be ensured to be within the login time slot range.

Redetermined login slot length:

the longest length of the registration time slot is actually determined by the distance offset between the closest point to the satellite and the farthest point from the satellite.

The closest point of the satellite is the equatorial position directly below the satellite, i.e. a bit with a longitude x and a latitude 0, and the distance H =35860 km.

The satellite farthest point is the satellite covering farthest point, and 81.3 degrees N is taken as an exampleLine calculation, distance Dm = ((R + H)²-R²)^1/2=41753.679 km. Wherein R is the radius of the earth.

The propagation delay deviation between the closest point and the farthest point is (Dm-H)/c = 19.6ms, where c is the speed of light 30 km/s.

Because there are two parts of time delay of forward link time delay and backward link time delay, the longest length of the obtained login time slot is: original login slot length +2 × 19.6 ms.

And (3) obtaining the corrected login starting time by a remote station local absolute time correction method:

in the case where the remote station has no GPS or inaccurate GPS location information, the remote station assumes that it is at the equatorial position directly below the satellite, i.e., a position with x longitude and 0 latitude. Based on this assumption, the remote station modified time slot of registration is T₀-2*(T_f+ H/c). Wherein H is the distance between the satellite and the ground 35860km, and c is the speed of light 30 km/s, as shown in FIGS. 5-6.

The assumed position of the remote station is the equatorial position right below the satellite, the position is the closest point to the satellite, and the transmission delay from any other point in the coverage range of the satellite to the central station is longer than the assumed point, namely at T₀-2*(T_f+ H/c) time, the time point when the central station receives the login signaling only lags behind T₀The longest lag time is 2 x (T)_f+H/c)。

In the login mode, any point in the satellite coverage area is logged in according to the time slot plan and falls within the login time slot range planned by the central station, and the data transmission of other stations is not influenced by shifting to an adjacent time slot.

Example two

The present embodiment provides a long uncertainty entry device for a TDMA satellite communication system, which has a structure as shown in fig. 7 and includes a time slot range module and a start time module.

The time slot range module is used for increasing a preset time length on the basis of the original length of the login time slot to be used as a redetermined login time slot length so that the redetermined login time slot length is used as a planned login time slot range of the central station;

the starting time module is used for taking a preset time interval in advance as a corrected login starting time on the basis of an original login starting time, and taking the corrected login starting time as a time slot login plan time of the remote station so as to allow the remote station to log in according to the time slot login plan time within a planned login time slot range;

the remote stations and the central station are both within the satellite coverage area of a star satellite TDMA system network.

Specifically, the time slot range module may be provided in the central station, and the start time module may be provided in the remote station, or the time slot range module and the start time module are provided together and located in a control device outside the central station and the remote station.

Specifically, in this example, the predetermined time length is determined according to the distance between the closest point and the satellite, and the distance between the farthest point and the satellite, where the closest point is the point on the surface of the earth closest to the satellite, and the farthest point is the point on the surface of the earth farthest from the satellite within the coverage of the satellite. The predetermined time length is less than or equal to 2 x (Dm-H)/c, wherein (Dm-H)/c is the transmission delay deviation between the nearest point and the farthest point, Dm is the distance between the farthest point and the satellite, and Dm = ((R + H)²-R²)^1/2H is the distance between the nearest point and the satellite, c is the speed of light 30 km/s, and R is the radius of the earth.

In particular, in the present example, the predetermined time interval is based on a link delay T from the central station to the satellite_fAnd the transmission delay T from the satellite to the remote station_bAnd (4) determining. The predetermined time interval is less than or equal to 2 (T)_f+ H/c), where H is the distance between the closest point to the satellite, the closest point being the point on the surface of the earth closest to the satellite, and c is the speed of light 30 km/s.

In the embodiment shown in fig. 2, the central station is point a. Assuming that the longitude of the satellite is x, the longitude of the satellite coverage on the earth is: x-81.3 DEG to x +81.3 DEG, with a coverage dimension in the range of 81.3 DEG N to 81.3 DEG S, at any point in this range a remote station may be present.

The closest point of the satellite is the equatorial position directly below the satellite, i.e. a bit with a longitude x and a latitude 0, and the distance H =35860 km.

The apparatus of this example, when executed, obtains a slot map as shown in fig. 4 and fig. 6.

EXAMPLE III

The present embodiment provides a computer-readable storage medium, on which a computer program is stored, which, when executed by a processor, controls an apparatus in which the storage medium is located to perform the TDMA satellite communication system long-time uncertain login method according to the first embodiment.

The above is only a preferred embodiment of the present invention and is not intended to limit the present invention, and it is apparent that those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.