CN106211294B

CN106211294B - AIS maritime search and rescue position indication mark and position indication method thereof

Info

Publication number: CN106211294B
Application number: CN201610746102.7A
Authority: CN
Inventors: 袁海峰
Original assignee: Shenzhen Quark Elec Technologies Co ltd
Current assignee: Shenzhen Quark Elec Technologies Co ltd
Priority date: 2016-08-29
Filing date: 2016-08-29
Publication date: 2023-09-01
Anticipated expiration: 2036-08-29
Also published as: CN106211294A

Abstract

The invention discloses an AIS maritime search and rescue bit indication mark and a bit indication method thereof, wherein the AIS maritime search and rescue bit indication mark comprises a GPS radio frequency front end, a GPS receiving module, an AIS radio frequency front end, an AIS receiving module, an AIS transmitting module, a baseband information processing module and a power module, the GPS receiving module is connected between the GPS radio frequency front end and the baseband information processing module, the AIS receiving module and the AIS transmitting module are respectively connected between the AIS radio frequency front end and the baseband information processing module, and the power module is also connected to the baseband information processing module. The electric quantity of the residual battery is checked in the search and rescue position indication calibration period, and meanwhile, the working state of the GPS module, the transmitting power of the AIS transmitting module and the transmitting interval time are dynamically adjusted according to the signal intensity of surrounding AIS equipment, so that the working time and the transmitting efficiency of the search and rescue position indication are improved to the greatest extent. The search and rescue position indicating mark further comprises a solar cell panel, the battery is charged through the photovoltaic effect, the working time of the search and rescue position indicating mark is prolonged, and the search and rescue effect is improved.

Description

AIS maritime search and rescue position indication mark and position indication method thereof

Technical Field

The invention relates to the field of marine communication equipment, in particular to an AIS maritime search and rescue position indication mark and a position indication method thereof.

Background

In recent years, with rapid development of ship technology and rising of marine economy, the status of marine transportation is increasingly remarkable, and the world shipping market is unprecedented to expand and develop. The rapid development of the world shipping industry brings great economic benefits and makes the maritime traffic situation more and more complex. Marine traffic accidents, which cause major personal injuries and deaths due to collisions, reefs, stranding, sinking, etc., still occur frequently. The life is invaluable, and the maritime search and rescue work has very important effect.

The AIS system is an effective marine collision avoidance, navigation and navigation aid safety system. According to the mandatory requirements of the International Maritime Organization (IMO), AIS equipment is installed on all international sailing vessels above 300 tons and non-international sailing vessels above 500 tons. While small vessels are not currently being forced to install such equipment, more and more small vessels are increasingly installing AIS equipment due to the self-locating nature of AIS and the gradual decrease in manufacturing costs.

An AIS maritime search and rescue position indication mark (AIS-MOB) is search and rescue position indication alarm equipment which can be installed on a life jacket or carried with a user, and the equipment can be started automatically after being manually started or fallen into water to send personal position and alarm information on an AIS channel or an assigned special channel. This information may be received and displayed by all AIS terminal equipment and base station equipment within a certain range. Once the person equipped with the AIS search and rescue indication marks falls into water, the personal position and alarm information can be acquired by surrounding ships or base stations. Rescue personnel can search and rescue the personnel in water immediately according to the position of the emergency search and rescue indication mark, and the search and rescue efficiency is improved.

Conventional AIS-MOBs typically include a battery, a start switch, a GPS locator, a microcontroller, an AIS controller, a modulator, a power amplifier, an AIS transmit antenna, and the like. The working principle is as follows: the starting switch is started manually or after water is met, the microcontroller receives the position information sent by the GPS locator, the information is subjected to data packet format conversion through the AIS controller, modulation coding through the modulator, signal amplification through the power amplifier, and finally the personal position and alarm information are sent through the AIS transmitting antenna. In this process, the GPS locator and the power amplifier are the main components that consume battery power. If there is no receiving device capable of receiving AIS signal after AIS-MOB falls into water within a certain distance, AIS-MOB emission belongs to invalid emission, only the limited electric energy of AIS-MOB battery is consumed, this directly results in shortening time for rescuing people in danger of falling into water and affecting search and rescue effect.

A more advanced technique is a search and rescue indicator as proposed in application number 2015103078144. According to the invention, whether to send or send the AIS signal is determined according to whether the surrounding AIS signal is received or not or at adjustable interval time, and because the power consumption of the AIS receiving device is smaller than that of the AIS transmitting device, the search and rescue bit indicator power consumption caused by invalid AIS signal sending due to the fact that no AIS receiving equipment exists around is avoided. However, such indicia have the following drawbacks:

whether 9-bit standard MMSI numbers or standard IMO numbers are received as standards for judging whether AIS transceiver equipment exists around is very limited for the current offshore situation in China. Many small ships (especially offshore cargo vessels, fishing vessels, etc. do not need to enter various vessels in open sea) have AIS transmitting and receiving functions, but are not registered in IMO (international maritime organization) and therefore do not have true MMSI or IMO numbers. So simply taking this as the standard misses many potential rescue opportunities. This is not optimal at key moments of the day of a humane fate.

The AIS signal transmitting power of the indication marks is fixed, and the more places with fewer surrounding ships are, the more the transmitting signal power is increased, the signal coverage is improved, and therefore the probability that the AIS signal can be found by other AIS equipment is improved.

Such a GPS locator for a position indicator is in continuous operation. While the GPS locator consumes 12% to 18% of its battery power in continuous operation. For the search and rescue position indicator with the battery working time almost equal to the rescue opportunity window time, if the working time of the position indicator can be improved by adjusting the sleep time of the GPS positioner, the time for sending the distress signal outwards is prolonged, and the success rate of search and rescue can be improved. Normally, the moving range of people falling into water does not change greatly in a short period, so that the search and rescue position indicator does not need to keep real-time updating of the position information under the condition of limited battery power, and the position information acquired by the GPS locator for the last time can be multiplexed in a short period.

Disclosure of Invention

The invention aims to provide an AIS maritime search and rescue position indicating mark and a position indicating method thereof, which are used for solving the problems in the background technology.

In order to achieve the above purpose, the present invention provides the following technical solutions:

the AIS maritime search and rescue bit mark comprises a GPS radio frequency front end, a GPS receiving module, an AIS radio frequency front end, an AIS receiving module, an AIS transmitting module, a baseband information processing module and a power module, wherein the GPS radio frequency front end is externally connected with a GPS antenna, the AIS radio frequency front end is externally connected with the AIS antenna, the GPS receiving module is connected between the GPS radio frequency front end and the baseband information processing module, the AIS receiving module and the AIS transmitting module are respectively connected between the AIS radio frequency front end and the baseband information processing module, and the power module is also connected on the baseband information processing module; the power module comprises a solar panel, a rechargeable battery and a power management and monitoring unit, wherein the rechargeable battery is respectively connected with the solar panel, the power management and monitoring unit, and the power management and monitoring unit is connected with the baseband information processing module.

As a further scheme of the invention: the GPS radio frequency front-end module comprises a low-noise amplifier and a band-pass filter, wherein the band-pass filter is connected with the low-noise amplifier, and the low-noise amplifier is connected with an external GPS antenna; the GPS receiving module comprises a down converter, an intermediate frequency amplifier and an analog-to-digital converter, wherein the down converter, the intermediate frequency amplifier and the analog-to-digital converter are sequentially connected, the down converter is connected with a band-pass filter, and the analog-to-digital converter is connected with a baseband information processing module.

As a further scheme of the invention: the AIS radio frequency front end comprises a low-pass filter, a receiving-transmitting change-over switch, a low-noise amplifier and a branching unit, wherein the low-pass filter is connected with an external AIS antenna, the receiving-transmitting change-over switch is connected between the low-pass filter and the low-noise amplifier, the receiving-transmitting change-over switch is also connected with an adjustable power amplifier of an AIS transmitting module, and the branching unit is connected between the low-noise amplifier and an AIS receiving module.

As a further scheme of the invention: the AIS receiving module comprises two independent receiving channels, each receiving channel comprises an acoustic surface filter, a down converter, an intermediate frequency filter and an analog-to-digital converter, the acoustic surface filter is connected with a splitter at the front end of AIS radio frequency, the acoustic surface filter, the down converter, the intermediate frequency filter and the analog-to-digital converter are sequentially connected, and the analog-to-digital converter is connected with the baseband information processing module;

as a further scheme of the invention: the AIS transmitting module comprises a digital-to-analog converter and an adjustable power amplifier which are sequentially connected, wherein the digital-to-analog converter is connected with the baseband information processing module, and the adjustable power amplifier is connected with the receiving and transmitting change-over switch.

The AIS maritime search and rescue position indication method specifically comprises the following steps:

step 1: starting a search and rescue indication bit marker, starting to work, setting an initial value of an emission interval time T of an AIS emission module as T1, setting an initial value of emission power P as P1, setting an initial value of a starting interval time A of a GPS module as 0, namely, continuously working the GPS without entering a dormant state, and setting an initial value of a battery electric quantity detection interval time B as B1;

step 2: judging whether the residual electric quantity of the battery is higher than a first percentage a%; if yes, executing the process of the step 3; otherwise, executing the process of the step 4;

step 3: the GPS module continuously works, continuously acquires current position information, sends the current position information to the baseband information processing module, and then enters step 9;

step 4: judging whether the residual electric quantity of the battery is higher than a second percentage b%; if yes, executing the process of the step 5; otherwise, executing the process of the step 10;

step 5: the GPS module continuously works, continuously acquires current position information, sends the current position information to the baseband information processing module, and then enters step 6;

step 6: the AIS receiving module detects RSSI values on two AIS receiving channels respectively, and then step 7 is carried out;

step 7: judging whether RSSIs of the two AIS receiving channels are higher than CdBm or not; if yes, executing the process of the step 9; otherwise, executing the step 8;

step 8: setting the transmitting power P of the AIS transmitting module as P2, and then entering step 9;

step 9: the AIS sending module sends AIS distress information according to the set time interval and sending power, and after every B1 time, the step 14 is entered;

step 10: the GPS module acquires current position information, sends the current position information to the baseband information processing module, and then enters step 11;

step 11: the starting interval time A of the GPS module is set to be A1, the GPS module then enters a dormant state, and then step 12 is carried out;

step 12: the interval transmission time T of the AIS transmission module is set to be T2, and then step 13 is carried out;

step 13: the baseband information processing module acquires the position information and simultaneously stores the position information; in the stage that the GPS module is in a dormant state, the last acquired GPS position information is always used as the current position information; the GPS module updates the position information after restarting in the dormant A1 time, and then enters step 6;

step 14: re-detecting the electric quantity of the primary battery, and then entering step 2;

as a further scheme of the invention: in the above steps, the first percentage a% is greater than the second percentage b%, the transmission power P1 of the AIS transmitting module is smaller than P2, and the transmission interval time T1 of the AIS transmitting module is smaller than T2.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, the GPS receiving module, the AIS receiving and transmitting module, the baseband information processing module and the power module are arranged in the search and rescue position indication mark, and the power and the interval transmitting time for the search and rescue position indication mark to transmit the AIS distress signal outwards can be dynamically adjusted according to the residual battery capacity and the strength of surrounding AIS transmitting device signals under the control of the baseband information processing module, so that the working time of the search and rescue position indication mark is prolonged, and the search and rescue efficiency is improved.

The invention dynamically adjusts the working state of the GPS receiving module according to the residual electric quantity of the battery, and when the GPS receiving module is in a dormant state, the last acquired position information is used as the current effective information for asking for help position information sent out by the AIS transmitting module. Generally, the moving range of people falling into water does not change greatly in a short period, so that the position information provided by the scheme in the actual search and rescue process is enough to use. The technical proposal has the advantages of prolonging the working time of the search and rescue position indication mark and improving the search and rescue efficiency.

The invention judges whether the surrounding AIS receiving device exists or not or whether the surrounding AIS receiving device is far or near by monitoring the RSSI value of AIS signals around the indication marks. Because a plurality of ships in China inland, inland and offshore are not strictly applied and used for IMO number and MMSI number, the method used by the invention is more suitable for national conditions, optimizes the actual monitoring effect and improves the search and rescue efficiency.

Drawings

FIG. 1 is a schematic diagram of a search and rescue beacon system of the present invention.

Fig. 2 is a schematic structural diagram of the GPS radio frequency front-end and the GPS receiving module of fig. 1.

Fig. 3 is a schematic structural diagram of the AIS radio frequency front end, the AIS receiving module and the AIS transmitting module of fig. 1.

FIG. 4 is a flow chart of the bit indicating method of the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Referring to fig. 1 to 3, in an embodiment of the present invention, an AIS maritime search and rescue beacon includes a GPS radio frequency front end 1, a GPS receiving module 2, an AIS radio frequency front end 3, an AIS receiving module 4, an AIS transmitting module 5, a baseband information processing module 6 and a power module 7.

As shown in fig. 1, the GPS radio frequency front-end 1 is externally connected with a GPS antenna, receives radio frequency signals, and sends the processed radio frequency signals to the GPS receiving module 2 for further processing.

As shown in fig. 1, a GPS receiving module 2 is connected to a GPS radio frequency front-end 1, and the GPS receiving module 2 performs down-conversion, signal amplification and analog-to-digital conversion on a radio frequency signal sent from the GPS radio frequency front-end 1, and then sends the signal to a baseband information processing module 6 for digital processing.

As shown in fig. 1, the AIS radio frequency front end 3 is externally connected with an AIS antenna, and is used for transmitting and receiving radio frequency signals. After the front-end processing is completed, the received radio frequency signals pass through an internal splitter and are divided into 2 paths and respectively sent into 2 channels of the AIS receiving module 4 for further processing. The AIS radio frequency front end 3 includes a transceiver change-over switch for time division multiplexing, and performs radio frequency signal receiving and transmitting conversion according to the instruction of the baseband information processing module 6. The AIS antenna respectively completes the functions of receiving and transmitting radio frequency signals in different time slots.

As shown in fig. 1, the AIS receiving module 4 is connected to the AIS radio frequency front end 3, and the AIS receiving module 4 performs filtering, down-conversion, intermediate frequency filtering and analog-to-digital conversion on the radio frequency signal sent from the AIS radio frequency front end 3, and then merges the 2 paths of signals and sends the merged signals to the baseband information processing module 6 for further digital processing.

As shown in fig. 1, the AIS transmitting module 5 is connected to the baseband information processing module 6, receives information sent by the baseband information processing module 6, and sends a processed analog signal to the AIS radio frequency front end 3. The AIS radio frequency front end 3 sends to the AIS antenna through the receiving and transmitting switch, thereby completing the emission of radio frequency signals.

As shown in fig. 1, the baseband information processing module 6 is connected to the GPS receiving module 2, the AIS receiving module 4, the AIS transmitting module 5, and the power supply module 7.

The baseband information processing module 6 performs the following functions:

(1) And receiving the digital signal from the GPS receiving module 2 to complete the analysis of the position information.

(2) The battery capacity information from the power module 7 is received, so that it is judged whether the transmission interruption time of the AIS transmitting module 5 is required to be prolonged for the purpose of prolonging the operation time of the indication mark and whether the intermittent operation of the GPS receiving module 2 is required to be set according to the remaining battery capacity. When the battery power is greater than the first percentage, it indicates that the battery is still sufficiently charged, and at this time, the AIS transmitting module 5 transmits the position information according to the first transmitting power value and the first time interval. When the battery power is smaller than the first percentage and larger than the second percentage, the battery power is indicated to be in the central range, and the baseband information processing module 6 compares the RSSI (strength indication of the received signal) value detected by the AIS receiving module 5 at the AIS frequency point with the initial set value. If the former value is smaller than the initial set value, the AIS receiving device is arranged at a place which is not around the indication mark or is far away from the indication mark. The AIS transmitting module 5 transmits the location information using the second transmit power to increase the chance of the signal being captured by other AIS receiving devices. Otherwise, setting the AIS transmitting module 5 according to the first power value. The first transmit power value is less than the second transmit power value. The first percentage of battery charge is greater than the second percentage. When the battery capacity is smaller than the second percentage capacity, the residual electric quantity of the battery is smaller, and the working time of the search and rescue indication marks can be supported. At this time, the baseband information processing module configures the GPS interval working time and sets the GPS module to enter a working or sleep state according to the GPS interval working time, thereby reducing the power consumption of the GPS. Meanwhile, the baseband information processing module 6 uses the second time interval to configure the interval time of AIS information transmission, so that the consumption electric quantity of the AIS transmitting module 5 is reduced, and the working time of the search and rescue indication bit mark is prolonged. The first time interval is less than the second time interval.

(3) And receiving the digital signals from the AIS receiving module 4, finishing signal detection of AIS signal frequency points, and calculating RSSI (received signal strength indication) values of the two frequency points. And comparing the detection result with the value initially set by the search and rescue indication bit standard, thereby setting the transmission power of the AIS transmission module 5. When the RSSI value obtained from the AIS receiving module 4 is lower than the indicator setting value, it means that there is no or a far distance around the indicator. At this time, the transmission power of the AIS transmission module 5 is set to the second power value to transmit the position information within the allowable range of the battery capacity, thereby improving the opportunity of capturing the signal by other AIS receiving devices. Otherwise, the AIS transmitting module 5 is set according to the first power value. The first power value is smaller than the second power value.

As shown in fig. 1, the power module 7 is used for supplying power to the whole system and has the functions of monitoring and protecting electric quantity. The power supply module 7 includes: a solar panel 71, a rechargeable battery 72, a power management and monitoring unit 73. The solar panel 71 is connected to the rechargeable battery 72, and conversion of light energy into electric energy is accomplished by using a photovoltaic effect, thereby charging the rechargeable battery 72. The rechargeable battery 72 provides power to the search and rescue beacon with a recharging function. The power management and monitoring unit 73 is connected to the rechargeable battery 72, implements voltage monitoring and transmits real-time voltage to the baseband information processing module 6. The baseband information processing module 6 thus determines the remaining power and thus the different modes of operation based on the voltage level of the rechargeable battery 72, so that the search and rescue indicator reaches an optimal operating state. The power management and monitoring unit 73 also realizes an overcurrent and overvoltage protection function for the rechargeable battery 72, and prolongs the service life of the rechargeable battery 72.

As shown in fig. 2, the GPS radio frequency front-end 1 is connected to the GPS receiving module 2, and the complete process of converting the radio frequency signal received from the GPS antenna into a digital baseband signal is completed. The GPS radio frequency front end 1 module comprises a low noise amplifier 11 and a band-pass filter 12. The low noise amplifier 11 receives the radio frequency signal from the antenna and performs a front-end signal amplifying function. The band-pass filter 12 is connected with the low noise amplifier 11 to realize the filtering of the front-end signal, filter the noise and allow the effective signal of the GPS frequency band to pass.

As shown in fig. 2, the GPS receiving module 2 includes: a down converter 21, an intermediate frequency amplifier 22, an analog-to-digital converter 23. The down converter 21 receives the radio frequency signal from the GPS band, mixes the radio frequency signal, and outputs an intermediate frequency signal lower than the GPS band. This intermediate frequency signal is subjected to signal amplification by an intermediate frequency amplifier 22, followed by conversion of the analog signal to a digital signal by an analog-to-digital converter 23. This digital signal is input to the baseband information processing module 6 for further digital signal processing. The down-converter 21 will use 4092Mhz as the intermediate frequency, preferably operating in this band.

As shown in fig. 3, the AIS radio frequency front end 3 is connected to an AIS receiving module 4 and an AIS transmitting module 5, respectively. The AIS radio frequency front end 3 includes a transceiver switch 32 therein for time division multiplexing, and performs conversion of radio frequency signal reception and transmission according to the instruction of the baseband information processing module 6. The AIS radio frequency front end 3 comprises: a low-pass filter 31, a transmit-receive switch 32, a low-noise amplifier 33, and a splitter 34. The low pass filter 31 is connected to the AIS antenna. The low-pass filter 31 performs high-frequency filtering of the received wireless signal when the AIS antenna is used as a receiving function. The low-pass filter 31 performs low-pass filtering on the radio frequency signal from the AIS transmitting module 5 when the AIS antenna is used as a transmitting function, and then feeds the signal into the AIS antenna to complete the signal transmitting function. One end of the transceiver switch 32 is connected with the antenna through the low-pass filter 31, and the other 2 end is respectively connected with the low-noise amplifier 33 and the adjustable power amplifier 51 of the AIS transmitting module 5. When the beacon is in operation, the transceiver switch 32 switches between the receiving and transmitting channels according to the instruction of the baseband information processing module 6. The low noise amplifier 33 is connected to the transmit-receive switch 32, and when the AIS antenna is used as a receiving function, the low noise amplifier 33 amplifies the radio frequency signal passing through the transmit-receive switch 32 and then feeds the amplified radio frequency signal to the splitter 34. The splitter 34 is connected to the low noise amplifier 33, and equally splits the radio frequency signal transmitted from the low noise amplifier 33 into 2 paths, and transmits the 2 paths to the AIS receiving module 4.

The AIS receiving module 4 comprises 2 independent receiving channels, each channel comprising a sound table filter 411, a down converter 412, an intermediate frequency filter 413, an analog-to-digital converter 414, operating on 2 frequency points of the AIS respectively. With the channel 141 as a column, the watch filter 411 is connected to the splitter 34 of the AIS radio frequency front end 3, receives the radio frequency signal, and performs conversion from the radio frequency signal to an intermediate frequency signal through the down converter 412, and then the intermediate frequency signal is input to the intermediate frequency filter 413 for band-pass filtering. The analog-to-digital converter 414 is connected to the intermediate frequency filter 413, and performs intermediate frequency signal digitizing processing for the intermediate frequency signal transmitted from the intermediate frequency filter 413. The digital signal sent by the analog-to-digital converter 414 is input to the baseband information processing module 6 for further digital signal processing. Similarly, the channel 2 completes the processing procedure of the radio frequency signal of the other channel.

The AIS transmit module 5 includes a digital-to-analog converter 52 and an adjustable power amplifier 51. The digital-to-analog converter 52 is connected to the baseband information processing module 6. When the search and rescue indication bit is in a transmitting state, the baseband information processing module 6 outputs information to be transmitted, and the information is converted from a digital signal to an analog signal through the digital-to-analog converter 52. The adjustable power amplifier 51 is connected with the digital-to-analog converter 52, and performs power amplification on the analog signal from the digital-to-analog converter 52, and then outputs the amplified signal to the AIS radio frequency front end 3, and sends the amplified signal to the AIS antenna through the transceiver switch 32, thereby completing the transmission of the radio frequency signal.

FIG. 4 is a flowchart of a method for indicating bits according to the present embodiment, and the flowchart of the present embodiment includes the following steps:

step 1: the search and rescue indication marks are started to start working. Setting the initial value of the transmission interval time T of the AIS transmission module as T1, and setting the initial value of the transmission power P as P1; the initial value of the starting interval time A of the GPS module is 0, namely the GPS continuously works and does not enter a dormant state, and the initial value of the battery electric quantity detection interval time B is set as B1;

step 3: the GPS module continuously works, continuously acquires current position information and sends the current position information to the baseband information processing module; the baseband information processing module acquires the position information and then enters step 9;

step 5: the GPS module continuously works, continuously acquires current position information and sends the current position information to the baseband information processing module. The baseband information processing module acquires the position information and then enters step 6;

step 6: the AIS receiving module detects RSSI values on 2 channels of AIS respectively, and then step 7 is entered;

step 7: judging whether RSSIs of the 2 AIS channels are higher than CdBm or not; if yes, executing the process of the step 9; otherwise, executing the step 8;

in the above embodiment, the first percentage a% is greater than the second percentage b%; the transmitting power P1 of the AIS transmitting module is smaller than P2; the transmission interval time T1 of the AIS transmission module is smaller than T2.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims

1. The utility model provides an AIS maritime search and rescue indication bit mark, includes GPS radio frequency front end (1), GPS receiving module (2), AIS radio frequency front end (3), AIS receiving module (4), AIS transmitting module (5), baseband information processing module (6) and power module (7), GPS radio frequency front end (1) external GPS antenna, AIS radio frequency front end (3) external AIS antenna, characterized in that, GPS receiving module (2) connect between GPS radio frequency front end (1) and baseband information processing module (6), AIS receiving module (4) and AIS transmitting module (5) are connected respectively between AIS radio frequency front end (3) and baseband information processing module (6), power module (7) are also connected on baseband information processing module (6); the power module (7) comprises a solar panel (71), a rechargeable battery (72) and a power management and monitoring unit (73), wherein the rechargeable battery (72) is respectively connected with the solar panel (71) and the power management and monitoring unit (73), and the power management and monitoring unit (73) is connected with the baseband information processing module (6);

the GPS radio frequency front end module (1) comprises a low-noise amplifier (11) and a band-pass filter (12), wherein the band-pass filter (12) is connected with the low-noise amplifier (11), and the low-noise amplifier (11) is connected with an external GPS antenna; the GPS receiving module (2) comprises a down converter (21), an intermediate frequency amplifier (22) and an analog-to-digital converter (23), wherein the down converter (21), the intermediate frequency amplifier (22) and the analog-to-digital converter (23) are sequentially connected, the down converter (21) is connected with a band-pass filter (12), and the analog-to-digital converter (23) is connected with a baseband information processing module (6);

the AIS radio frequency front end (3) comprises a low-pass filter (31), a receiving and transmitting change-over switch (32), a low-noise amplifier (33) and a branching unit (34), wherein the low-pass filter (31) is connected with an external AIS antenna, the receiving and transmitting change-over switch (32) is connected between the low-pass filter (31) and the low-noise amplifier (33), the receiving and transmitting change-over switch (32) is also connected with an adjustable power amplifier (51) of an AIS transmitting module (5), and the branching unit (34) is connected between the low-noise amplifier (33) and an AIS receiving module (4);

the AIS receiving module (4) comprises two independent receiving channels, each receiving channel comprises a sound meter filter (411), a down converter (412), an intermediate frequency filter (413) and an analog-to-digital converter (414), the sound meter filter (411) is connected with a splitter (34) of the AIS radio frequency front end (3), the sound meter filter (411), the down converter (412), the intermediate frequency filter (413) and the analog-to-digital converter (414) are sequentially connected, and the analog-to-digital converter (414) is connected with the baseband information processing module (6);

the AIS transmitting module (5) comprises a digital-to-analog converter (52) and an adjustable power amplifier (51) which are sequentially connected, wherein the digital-to-analog converter (52) is connected with the baseband information processing module (6), and the adjustable power amplifier (51) is connected with the receiving-transmitting change-over switch (32).

2. An AIS maritime search and rescue signpost locating method according to claim 1, which is characterized by comprising the following specific steps:

step 14: the primary battery charge is re-detected and then step 2 is entered.

3. The method of locating an AIS marine search and rescue locating symbol according to claim 2 wherein in the above steps, the first percentage a% is greater than the second percentage b%, the transmission power P1 of the AIS transmitting module is less than P2, and the transmission interval time T1 of the AIS transmitting module is less than T2.