CN115243244A

CN115243244A - Method and system for short-range coverage expansion extension in motorized emergency communication system

Info

Publication number: CN115243244A
Application number: CN202210697066.5A
Authority: CN
Inventors: 王雨晨; 车四四; 孙丽丽; 李冬; 刘鸿雁; 王朔; 张延童; 何子亨; 李然; 刘方舟; 郑广宁
Original assignee: State Grid Corp of China SGCC; Information and Telecommunication Branch of State Grid Shandong Electric Power Co Ltd
Current assignee: State Grid Corp of China SGCC; Information and Telecommunication Branch of State Grid Shandong Electric Power Co Ltd
Priority date: 2022-06-20
Filing date: 2022-06-20
Publication date: 2022-10-25

Abstract

The invention provides a method and a system for short-range coverage extension in a motorized emergency communication system, which comprises the following steps: the system comprises a plurality of Mesh ad hoc network devices, LTE devices and AP devices; one Mesh ad hoc network device is connected to the satellite vehicle internet at a vehicle-mounted station, and after other Mesh ad hoc network devices are started, ad hoc network is carried out according to the preset IP address and the condition of received signal power; the LTE equipment is accessed to the satellite vehicle Internet at a base station, and video return and map positioning are carried out through the LTE equipment; and the AP equipment accesses the Internet at the satellite vehicle, expands the coverage range of the Wi-Fi signals, realizes Internet access and expands the short-range coverage range.

Description

Short-range coverage extension method and system in motorized emergency communication system

Technical Field

The invention belongs to the technical field of information communication, and particularly relates to a short-range coverage extension method and system in a motorized emergency communication system.

Background

The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.

Under the electric power emergency scene of speedily carrying out rescue work, for example, when disasters such as some torrential rain appear, electric power system originally adopts individual soldier's system to salvage the contact between personnel and the emergency communication car, adopts the satellite passageway, contacts with this department emergency command center with the help of the mode of emergency communication car. However, if the rainstorm disaster is serious, the public network is damaged, and the individual soldier system is limited by the technology and can only be used within 1.5km of the emergency communication vehicle, the communication effect is poor, if the distance is exceeded, the individual soldier can not establish contact with the emergency communication vehicle, and only the special equipment can be used by the individual soldier, and the individual soldier can only hear the sound on the spot and cannot see the satellite vehicle and the command department image.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a method for expanding and extending short-range coverage in a motorized emergency communication system, and the method expands the range of short-range coverage.

In order to achieve the above object, one or more embodiments of the present invention provide the following technical solutions:

in a first aspect, a system for short range coverage extension in an automotive emergency communication system is disclosed, comprising:

the system comprises a plurality of Mesh ad hoc network devices, LTE devices and AP devices;

one Mesh ad hoc network device is connected to the satellite vehicle internet at a vehicle-mounted station, and after other Mesh ad hoc network devices are started, ad hoc network is carried out according to the preset IP address and the condition of received signal power;

the LTE equipment is accessed to the satellite vehicle Internet at a base station, and video return and map positioning are carried out through the LTE equipment;

the AP equipment accesses the Internet at the satellite vehicle, enlarges the coverage range of Wi-Fi signals, realizes Internet access and expands the short-range coverage range.

As a further technical scheme, the terminal equipment is accessed into the Mesh ad hoc network equipment in a Wi-Fi or network cable connection mode, reaches equipment at the vehicle-mounted station through one-hop or multi-hop transmission, is accessed into the internet, and realizes video return through the terminal equipment.

As a further technical scheme, the system also comprises CPE equipment which receives signals of the base station and converts LTE signals into Wi-Fi signals and Ethernet signals so as to realize internet access of a mobile phone terminal around the CPE and a notebook computer.

The technical scheme includes that the system further comprises a central station, the central station is connected with the Internet, a satellite vehicle is connected with the Internet through a satellite transmission channel, the local switch is connected with an AP/LTE/Mesh device, and a terminal device is connected with a coverage expansion device through Wi-Fi or network cable access to achieve Internet access.

As a further technical scheme, if the number of the Mesh ad hoc network devices is three, a first Mesh ad hoc network device is connected to the satellite vehicle internet through a network switch, and the other two Mesh ad hoc network devices are respectively connected to the first Mesh ad hoc network device.

In a second aspect, a method for short-range coverage extension in an automotive emergency communication system is disclosed, comprising:

under the mode of local networking, a central station is accessed to the Internet, a satellite vehicle is accessed to the Internet through a satellite transmission channel, a local switch is connected with AP/LTE/Mesh equipment, and a terminal is accessed to coverage expansion equipment through Wi-Fi or network cable access to realize Internet access.

In a third aspect, a method for testing a system with extended short-range coverage in a mobile emergency communication system is disclosed, which comprises the following steps:

and LTE equipment testing: carrying out equipment communication coverage capability test, equipment data transmission quality test and update meeting APP application test;

testing Mesh ad hoc network equipment: carrying out speed tests at 1 kilometer and 1.5 kilometers, single-hop limit communication distance and speed tests and two-hop communication speed tests;

AP equipment testing: and carrying out coverage range test, speed test and Tencent conference APP application test.

As a further technical scheme, the method also comprises ultrashort wave equipment testing, and specifically comprises the following steps: bi-pass, single-pass and through service distance tests, narrowband ad hoc network single-hop maximum communication distance tests, call definition and integrity tests in an equipment networking mode and narrowband ad hoc network intercommunication tests.

As a further technical solution, in bi-pass, uni-pass and pass-through service distance tests:

the bi-pass service distance refers to the distance between the farthest mobile station and the relay station under the condition that the mobile station can carry out two-way communication within the coverage range of the relay station;

the one-way service distance refers to the distance between the farthest mobile station and the relay station under the condition that the mobile station can only receive calls within the coverage range of the relay station;

the direct service distance refers to the distance that the two mobile stations normally use the voice service without passing through the relay station.

As a further technical scheme, when testing the maximum communication distance of a single hop of the narrowband ad hoc network:

the tested equipment A is fixed in the test park, the tested equipment B selects points in the urban area, the tested equipment B uses the hand microphone to periodically initiate networking test, the hand microphone test result is observed, and when three continuous tests are interrupted and can not be communicated, the maximum communication distance meeting the conditions is recorded.

The above one or more technical solutions have the following beneficial effects:

aiming at the insufficient covering capability of an individual soldier system, the invention can exceed the distance limit of 1.5 km; the current individual soldier system can only ensure that a single person can get in contact with an emergency communication vehicle, the invention can ensure that people around a Mesh end or a lte end have the same ability of getting in contact with the emergency communication vehicle, the current individual soldier system can only use special equipment for communication, and the invention can ensure that the personal mobile phone, the notebook computer and other devices for systems can access Wi-Fi of Mesh for internet access; the single soldier system field personnel in front can only hear the sound signal of the back, can't see the picture, the invention can guarantee the field personnel and commander audio and video conversation of the back.

Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a general schematic diagram of an embodiment of the present invention;

fig. 2 is a schematic view illustrating access of multiple Mesh ad hoc network devices according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of LTE device access in the embodiment of the present invention

Fig. 4 is a schematic view illustrating access of an AP device according to an embodiment of the present invention;

FIG. 5 is a two-hop test equipment connection diagram;

fig. 6 is a gorgeous Mesh ad hoc network equipment complementary graph and rate test;

FIG. 7 is a graph of how much energy is added to the Mesh ad hoc network device and a rate test graph;

FIG. 8 is a graph of incremental ad hoc network device padding and rate testing;

fig. 9 is a schematic view of the situation of the network band of the AP device 5G;

fig. 10 is a schematic view of the AP device 2.4G network band;

FIG. 11 is a schematic diagram of a 5G network fluctuation situation of the AP device;

fig. 12 is a schematic diagram of the fluctuation situation of the AP device 2.4G network;

FIG. 13 is a schematic diagram of a 5G network fluctuation situation of the Sharp AP device;

FIG. 14 is a schematic diagram of a 2.4G network fluctuation situation of the Sharp AP device;

fig. 15 is a schematic view of the connection of the intercom terminal;

fig. 16 a narrowband ad hoc network interworking schematic.

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention.

The embodiments and features of the embodiments of the invention may be combined with each other without conflict.

Example one

Referring to fig. 1, the embodiment discloses a system for extending short-range coverage in a motorized emergency communication system, which includes:

The Mesh ad hoc network device, the LTE device and the AP device have different application scenes. LTE can only use special equipment to return video, and a CPE (customer premise equipment) is required to realize personal equipment access. LTE devices can implement mapping functions, which is unique. AP devices are used for network deployment near satellite vehicles, which is simplest, but with closer coverage. The Mesh device can realize long-distance network coverage. The access of the mobile terminal is a public network, and the equipment for response needs to be selected according to actual conditions (distance and whether map positioning is needed or not). All three can be changed into vehicle-mounted stations.

In this embodiment, referring to fig. 2, a schematic view of access of multiple Mesh ad hoc network devices is shown. And one device is connected to the satellite vehicle internet at the vehicle-mounted station. And after starting other multiple Mesh devices, performing ad hoc network according to preset IP addresses and received signal power conditions. Personal terminal equipment such as a mobile phone and a notebook computer can access the Mesh equipment in a Wi-Fi or network cable connection mode, reach equipment at a vehicle-mounted station through one-hop or multi-hop transmission, realize internet access, and realize functions such as video return and the like through software of the personal terminal. The existing equipment only supports the coverage of a small range around a vehicle-mounted station, the coverage range can be expanded to at least 1km through multi-hop transmission of Mesh ad hoc network equipment, and the video return is realized through a personal terminal.

Specifically, referring to fig. 2, one end of the Mesh ad hoc network device a is connected to the internet through a network switch, the other end of the Mesh ad hoc network device a is connected to the Mesh ad hoc network device B, mesh ad hoc network device C, and the Mesh ad hoc network device B, mesh ad hoc network device C communicates with the personal smart phone through a wireless network, so that data transmission is achieved.

In this embodiment, referring to fig. 3, which is an access schematic diagram of an LTE device, the LTE device accesses a satellite vehicle internet at a base station, and video return and map positioning are implemented by using a proprietary device; CPE equipment can be equipped to receive signals of the base station and convert LTE signals into Wi-Fi signals and Ethernet signals, and internet access of personal mobile phone terminals and notebook computers around the CPE is achieved. The existing equipment only supports the coverage of a small range around the vehicle-mounted station, and the coverage range of video return can be expanded to about 1km through the LTE equipment and the special handheld terminal, and the Internet access function is realized. The cooperation of the LTE and the CPE can enable the personal terminal to realize the internet access function through the base station, and the coverage range is expanded.

Specifically, referring to fig. 3, the LTE base station accesses the internet through a network switch, the LTE base station communicates with the LTE device dedicated terminal and the LTE device CPE, and the LTE device CPE performs information interaction with the intelligent terminal through the network.

In this embodiment, referring to fig. 4, for an access schematic diagram of an AP device, the AP device accesses the internet at a satellite vehicle, and accesses Wi-Fi through a personal device and a laptop to implement internet access, compared with a home device, the AP device may expand a coverage range of a Wi-Fi signal to about 100m, implement internet access, and expand a short-range coverage range.

Specifically, referring to fig. 4, the AP device vehicle-mounted end accesses the internet through a network switch, and performs information interaction with the intelligent terminal through the network.

Referring to the mode of local networking of the mobile emergency communication system again, referring to fig. 1, a central station accesses the internet, a satellite vehicle accesses the internet through a satellite transmission channel, a local switch is connected with an AP/LTE/Mesh device, and a personal terminal accesses a coverage extension device through Wi-Fi or network cable access to realize internet access.

According to the technical scheme, any one of three schemes can be selected according to actual conditions, ap equipment can be adopted nearby the vehicle, and the method is simplest; if the distance is farther, mesh can be adopted, and if a map positioning function is required to be provided, lte equipment needs to be selected.

Example two

In this embodiment, a method for extending short-range coverage extension in an automotive emergency communication system is disclosed, comprising:

Specifically, a switch is connected near the satellite vehicle, and the switch is connected with AP \ LTE \ AP equipment;

contacting a national network central station, allocating bandwidth and establishing an access internet channel;

the personnel bear the LET \ MESH equipment, and cover network signals along the way in a multi-equipment cascade mode, and the AP equipment does not need to bear an erection environment due to short coverage distance;

and completing internet access, and completely completing network erection of remote first-aid repair personnel, communication vehicles, central stations and emergency command centers.

EXAMPLE III

In this embodiment, a method for testing a system with extended short-range coverage extension in a mobile emergency communication system is disclosed, comprising:

AP equipment testing: and performing coverage range test, speed test and Tencent meeting APP application test.

The above-mentioned scheme of the embodiment of the present disclosure is tested, and the specific test report is as follows:

1. short-range coverage aspect test recording

LTE equipment testing

1. Test equipment list

Serial number	Device name	Model number	Unit of	Number of	Remarks for note
						1	LTE piggyback station	Table (Ref. Table)	1	Antenna and the like
2	Portable CPE		Table (Ref. Table)	1	Antenna and the like
						3	Hand-held terminal	Table (Ref. Table)	3
4	Notebook computer		Table (Ref. Table)	1	Speed measuring running flow

2. Test method

2.1 device communication coverage capability test

(1) The LTE bearing base station (hereinafter referred to as the base station) is placed in a test fixed place, networking and frequency selection are automatically completed after the LTE bearing base station is started, and a tester holds the LTE hand station to carry out the limit communication distance test;

(2) Taking the base station as a central point, a tester advances to the periphery by a fixed line, uses notebook computer signal scanning software (such as inSSIDer) to check the signal intensity of the wireless network, and respectively records the linear distance from the point position to the base station when the signal intensity is stabilized at-65 dbm, -70dbm and-90 dbm.

2.2 device data Transmission quality testing

(1) A terminal accesses a base station;

(2) And (4) selecting points at a distance of 0.5 kilometer and 1 kilometer from the base station, and recording the data transmission rate and the network fluctuation condition by using terminal speed measurement software.

2.3 Tencent meeting APP application testing

(1) In a test site, respectively communicating a base station with satellite equipment at test points 0.5 kilometer and 1 kilometer away from the base station, and accessing the internet;

(2) And testing the functions of the mobile video conference by using the Tencent conference under the scene that the LTE mobile station and the notebook computer are connected with the CPE respectively.

3. Test record

3.1 tripod bridge communication (Huashi)

The equipment model is as follows: LTE piggyback station MiniRapid

Portable CPE EG860

Hand-held terminal EP821

Power: piggy-back platform 2 x 10W

Frequency band: 600MHz and bandwidth 20MHz

Table 1 table for recording coverage capability and data transmission quality of LTE equipment

Table 2: APP test condition recording table for Tencent meeting of Ding bridge LTE equipment

4.2 far east communication

The equipment model is as follows: LTE piggyback station IKLS600

Portable CPE LDC810

Hand-held terminal LHT650

Power: back carrying table 10W

Frequency band: 450MHz, bandwidth 5MHz/10MHz/15MHz/20MHz

Table 3: far east communication LTE equipment coverage capability and data transmission quality recording table

Table 4: APP test condition recording table for far east communication tench conference

4.3 Zhongxing Gaoda

The equipment model is as follows: LTE piggyback station P300

CPE Portable station GD600

Handheld terminal GH880

Table 5: zhongxing LTE-high equipment coverage capability and data transmission quality recording table

Table 6: advance news meeting APP test condition record table

(II) Mesh ad hoc network equipment test

1. Test equipment list

TABLE 7

Serial number

Device name

Model number

Unit of

Number of

Remarks to note

1

MESH bearing table or hand table

Sleeve

3

Antenna and the like

2

Notebook computer

Table (Ref. Table)

2

Speed measuring running flow

2. Test method

2.1 Velocity measurement at 1km, 1.5km

The device A is positioned in a test field, the test device B is positioned 1 kilometer and 1.5 kilometers outside the test field, and the speed is tested through Jperf software;

2.2 Single hop Limit communication distance and Rate testing

The device A is in a test field, the test device B selects points outside the test field, the speed is tested through Jperf software, and the maximum communication distance is recorded;

2.3 two-hop communication Rate testing

On the basis of the single-hop limit communication distance, a device C is added between the device a and the device B to serve as a relay point, a two-hop communication rate test is performed, and the communication distance is recorded, as shown in fig. 5.

3. Test record

3.1 Huaxia Sheng

The equipment model is as follows: mesh bearing table MM10 is multiplied by 2-1400-38-1

Hand-held table MM 2X 2-1400-6.8-1

Power: piggyback 2 x 10W, handheld 2 x 2W

Frequency band: 1.4G, 20MHz bandwidth

The method is characterized in that: after three hops, the bandwidth is not attenuated any more, the frequency is intelligently selected, and the interference resistance is avoided, and a Huaxia Sheng Mesh ad hoc network equipment complement diagram and a rate test are shown in an attached figure 6.

Table 8: huaxia Sheng Mesh ad hoc network equipment performance test recording table

4.2 sea energy to

The equipment model is as follows: mesh piggyback platform imesh-3800p

Fixed station imesh-3800V

Power: bear platform 2 x 2W, fixed station 2 x 5W

Frequency band: about 580MHz and bandwidth of 10MHz

The method is characterized in that: after three hops, the bandwidth is not attenuated any more, and the complementary graph and the rate test of the sea energy reach Mesh ad hoc network equipment are shown in the attached figure 7.

Table 9: performance test recording table for sea energy reach Mesh ad hoc network equipment

4.3 Zhongxing Gaoda

The equipment model is as follows: mesh bearing platform ZXIMCU sMesh100

Power: piggyback platform 2 x 2W

Frequency band: 566-626MHZ, bandwidth 5/10/20MHZ, zhongxing Gao Mesh ad hoc network equipment complement diagram and rate test are shown in figure 8.

Table 10: zhongxing Haoda Mesh ad hoc network equipment performance test recording table

4.4 Huiminjie

The equipment model is as follows: mesh handheld station HMJ-500ZJ

Power: back carrying table 2 x 0.5W

Frequency band: 1.4GHZ, 20MHz bandwidth

Table 11: comet-mingjie Mesh ad hoc network equipment performance test recording table

4.5 Nanjing Jingdi

The equipment model is as follows: comdi ICS-V1

Power: 2W

Transmission bandwidth: 20M

The method is characterized in that: customized equipment, and equipment integrating wireless AP and MESH

Table 12: performance test recording table for Jingdi Mesh ad hoc network equipment

(III) AP Equipment testing

1. Test equipment list

Watch 13

Serial number

Device name

Model number

Unit of

Number of

Remarks for note

1

Wireless AP

Sleeve

1

See the records of each manufacturer

2

Notebook computer

Table (Ref. Table)

2

Speed measuring running flow

2. Test method

2.1 coverage test

And testing the coverage ranges of the AP equipment under the frequencies of 5G and 2.4G, and recording the signal strength and the speed under-65 dbm, -70dbm and-90 dbm respectively by utilizing INSSIDER and Jperf software.

2.2 Rate testing

Recording data and screenshot by using a speed measuring software Jperf to test the speed and the network fluctuation condition of the equipment at 100 meters;

2.3 Tencent meeting APP application testing

And testing the video transmission quality of the Tencent meeting APP by utilizing the internet of the satellite channel, and recording the communication distance.

Test record

4.1 Hua is

The equipment model is as follows: airEngine6760R-51 omnidirectional built-in antenna

Theoretical coverage: radius 150 m, weight: 3KG

The method is characterized in that: two AP modes of supporting fat and thin

Table 14: huacheng wireless AP coverage and transmission quality recording table

Fig. 9 shows a case of 5G network bands of the Huawei AP device, and fig. 10 shows a case of 2.4G network bands of the Huawei AP device.

Table 15: huawei AP equipment flight meeting APP application test record table

4.2 Xinrui

The equipment model is as follows: NAP-8220-X omnidirectional external antenna

Radius of theoretical coverage 150 m

Table 16: xinrui wireless AP coverage and transmission quality recording table

Fig. 11 shows the case of the waviness of the 5G network of the trusted AP device. Fig. 12 shows the fluctuation of the AP device 2.4G network.

Table 17: credit-sharp AP equipment Tencent meeting APP application test record table

4.3 Shajie

The equipment model is as follows: RG-AP680-A omnidirectional built-in antenna

Radius of theoretical coverage 150 m

Table 18: sharp wireless AP coverage and transmission quality recording table

The fluctuation situation of the sharp AP device 5G network is shown in figure 13, and the fluctuation situation of the sharp AP device 2.4G network is shown in figure 14.

Table 19: APP application test record table for rapid AP equipment Tencent meeting

4.4 Nanjing Jingdi

The equipment model is as follows: comdi ICS-V1

Power: 1W; bandwidth: 20M; an antenna: orientation

Theoretical coverage radius: 300 m (without shelter)

Table 20: nanjing jingdi wireless AP coverage and transmission quality recording table

Table 21: APP application test record table for Tencent meeting of Nanjing Jingdi AP equipment

(IV) ultrashort wave device testing

1. Test equipment list

TABLE 22

Serial number

Device name

Model number

Unit

Number of

Remarks for note

1

PDT mobile station

IPS371

Table (Ref. Table)

1

2

PDT (portable digital power) hand table

AP600

Platform

3

Relay station

E-pack100

Sleeve

5

4

Terminal device

PD780

Table (Ref. Table)

5

Dispatching desk

E-center

Table (Ref. Table)

1

2. Test method

2.1 Bi-pass, uni-pass and straight-through service distance testing

The bi-pass service distance is the distance between the farthest mobile station and the relay station under the condition that the mobile station can carry out two-way conversation in the coverage area of the relay station.

The one-way service distance is the distance between the farthest mobile station and the relay station under the condition that the mobile station can only receive the call in the coverage of the relay station.

(1) And (4) antenna installation and cluster system construction.

(2) The equipment actually measures, under the direct dialing state of the mobile phone, the mobile phone takes the relay station as the center to advance 1000 meters to the fixed line for carrying out the talkback test, and the communication quality (clear, stuck, missing words and the like) and the communication state (double-pass, single-pass and ultra-range) are recorded.

2.2 narrowband Ad hoc network single-hop maximum communication distance test

The method comprises the following steps that a tested device A is fixed in a test park, a tested device B selects points in an urban area, the tested device B uses a hand microphone to initiate networking test periodically, the hand microphone test result is observed, and when three continuous tests are interrupted and cannot be communicated again, the maximum communication distance meeting conditions is recorded;

2.3 testing the call definition and integrity under the networking mode of the device

1 equipment is fixed in the garden, and other 4 equipment are in the garden and are looked for some, form 5 equipment network deployment, carry out the voice call test.

2.4 test of intercommunication between narrowband ad hoc network and existing communication vehicle-mounted station

The piggyback relay station is connected to a digital intercom terminal by a companion line, as shown in fig. 15. And carrying out a call test between A and B.

2.5 narrowband Ad hoc network intercommunication testing

The method comprises the steps that wide-band and narrow-band equipment (iMesh 3800P, E-pack 100) of a field emergency system is accessed to the system in a wired mode, and PUC software establishes a fusion group and calls the fusion group;

the PD780 under the narrowband E-pcak communicates with the PDC680 under the wideband POC, and the intercommunication diagram of the narrowband ad hoc network is shown in fig. 16.

3. Test record

4.1 far east communication

The equipment model is as follows: PDT Mobile station IPS371

PDT hand table AP600

Table 23: far east communication service distance test recording table

4.2 sea energy to

The equipment model is as follows: relay station E-pack100

Terminal PD780

Dispatcher station E-center

Table 24: test condition recording table for narrow-band ad hoc network modes of sea energy

Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.

Claims

1. A system for short range coverage extension in a motorized emergency communication system, comprising:

2. The system of claim 1, wherein the terminal device accesses the Mesh ad hoc network device through Wi-Fi or network cable connection, and reaches the device at the vehicle station through one-hop or multi-hop transmission to perform internet access, and implements video return through the terminal device.

3. The mobile emergency communication system of claim 1, further comprising CPE equipment for receiving signals from the base station and converting LTE signals into Wi-Fi signals and ethernet signals to enable internet access to the mobile phone terminals and the notebook computer around the CPE equipment.

4. The system of claim 1, further comprising a central station, wherein the central station accesses the internet, the satellite vehicle accesses the internet through a satellite transmission channel, the local switch is connected to the AP/LTE/Mesh device, and the terminal device accesses the coverage extension device through Wi-Fi or network cable access to realize internet access.

5. The system of claim 1, wherein if there are three Mesh ad-hoc devices, the first Mesh ad-hoc device is connected to the satellite vehicle internet through the network switch, and the other two Mesh ad-hoc devices are connected to the first Mesh ad-hoc device respectively.

6. A method for extending short-range coverage extension in a motorized emergency communication system, comprising:

7. The test method of the short-range coverage expansion extension system in the mobile emergency communication system is characterized by comprising the following steps:

8. The method for testing a short-range coverage extension system in a mobile emergency communication system of claim 7, further comprising ultrashort-wave device testing, in particular: bi-pass, single-pass and through service distance tests, narrowband ad hoc network single-hop maximum communication distance tests, call definition and integrity tests in an equipment networking mode and narrowband ad hoc network intercommunication tests.

9. The method of claim 7 for testing a short range coverage extension system in a mobile emergency communication system, wherein in the two-pass, one-pass and one-pass traffic distance tests:

the single-channel service distance refers to the distance between the farthest mobile station and the relay station under the condition that the mobile station can only receive the call in the coverage range of the relay station;

10. The method for testing a short-range coverage extension system in a mobile emergency communication system according to claim 7, wherein, during the narrow-band ad-hoc network single-hop maximum communication distance test: