Maritime wireless communication system and method thereof

1. A maritime wireless communication system performing wireless communication between at least one buoy, a fishing vessel terminal device, a managing vessel terminal device, or a land control center, the maritime wireless communication system comprising:

a communication module installed in the at least one buoy, providing sensing information using at least one sensor, providing identification information and location information for the at least one buoy, and ensuring communication connectivity when an event condition including fishing gear loss occurs; and

a gateway device installed in each of the fishing vessel terminal device and the managing vessel terminal device, performing communication with the at least one buoy and the land control center via a long range (LoRa)-based communication network to provide various types of fishery information including locations and conditions of a fishing vessel and fishing gear and a location of lost fishing gear, and setting different communication options for a normal condition and the event condition in performing a communication connection function, wherein

the communication module of the at least one buoy and the gateway device installed in each of the fishing vessel terminal device and the managing vessel terminal device form a main communication channel through a public LoRa network for low-power long-range communication and, in a shadow area, releases the main communication channel with the public LoRa network and then forms a sub communication channel through a private LoRa network, and wherein

the gateway device sets a reference spreading factor applied to each of the at least one buoy based on a communication quality of the at least one buoy and changes the reference spreading factor into a spreading factor higher than the reference spreading factor when the event condition occurs in performing communication with the at least one buoy, and the gateway device, when no event situation is detected, communicates with the at least one buoy at a spreading factor not more than the reference spreading factor to receive location information or battery status information from the buoy and transmits control information to the at least one buoy,

wherein the at least one buoy includes:

a power module providing power required for operating the at least one buoy;

a sensor module including at least one of a temperature sensor, an acceleration sensor, and an acoustic sensor and providing detected information;

a global positioning system (GPS) reception module providing the location information for the at least one buoy using a GPS signal;

a light indicator indicating a location of the at least one buoy; and

a control module processing a signal transmitted or received by the communication module and controlling an overall operation of the at least one buoy, wherein

each of the fishing vessel terminal device and the managing vessel terminal device includes the gateway device, a terminal, and an underwater acoustic tracker, wherein

the underwater acoustic tracker includes:

a serial interface (I/F) unit connected with the terminal using serial communication; a transmission sensor transmitting an acoustic signal to the at least one buoy;

a reception sensor receiving an acoustic signal from the at least one buoy;

a multi-channel signal processing module detecting all information transmitted from the at least one buoy;

a multi-channel sound transmission module and a multi-channel sound reception module receiving a sound signal of a frequency band ranging from 5 Hz to 2,400 Hz at a certain depth, analyzing a strength and direction of the sound signal, multiplexing or demultiplexing the analyzed sound signal, and then transmitting the multiplexed or demultiplexed sound signal;

a control module receiving a communication option and the identification information for the at least one buoy from the terminal, transmitting, to the at least one buoy, the identification information according to the communication option, receiving the identification information for the at least one buoy and battery status information from the at least one buoy, and transmitting the received identification information and battery status information to the terminal; and

a battery providing power required for operating the underwater acoustic tracker, and wherein the gateway device measures the communication quality based on signal quality including a received signal strength indication (RSSI) or a signal-to-noise ratio (SNR) of a signal transmitted or received with the at least one buoy and sets the reference spreading factor based on the measured communication quality.

2. The maritime wireless communication system of claim 1 , wherein the gateway device includes:

a broadband communication module supporting Internet-of-things (IoT) platform-based low-power broadband communication;

a public LoRa module supporting a wireless protocol with the public LoRa network; a private LoRa module supporting a wireless protocol with the private LoRa network;

a GPS reception module providing location information for the fishing vessel terminal device or the managing vessel terminal device using a GPS signal; and

a control module selectively connecting to the public LoRa network or the private LoRa network depending on a state of the public LoRa network or the private LoRa network, setting a communication option depending on the normal condition or the event condition, and controlling the broadband communication module, the public LoRa module, the private LoRa module, and the GPS reception module.

3. The maritime wireless communication system of claim 1 , wherein as the reference spreading factor increases, a spreading range and a data transmission speed of the gateway device increase.

4. The maritime wireless communication system of claim 1 , wherein as the reference spreading factor increases, a minimum SNR value and a data transmission rate of the gateway device decrease.

5. A maritime wireless communication method performing wireless communication between at least one buoy, a fishing vessel terminal device, a managing vessel terminal device, or a land control center, the maritime wireless communication method comprising

setting a reference spreading factor applied to each of the at least one buoy based on a communication quality of the at least one buoy by a gateway device installed in the fishing vessel terminal device or the managing vessel terminal device;

performing communication with the at least one buoy using the set reference spreading factor to receive sensing information obtained using at least one sensor and identification information and location information for the at least one buoy; and

analyzing the information received from the at least one buoy and, when an event condition including fishing gear loss occurrence, changing the reference spreading factor into a spreading factor higher than the reference spreading factor in performing communication with the at least one buoy, wherein the gateway device, when no event situation is detected, communicates with the at least one buoy at a spreading factor not more than the reference spreading factor to receive location information or battery status information from the at least one buoy and transmits control information to the at least one buoy, and

wherein the at least one buoy includes:

a power module providing power required for operating the at least one buoy;

a sensor module including at least one of a temperature sensor, an acceleration sensor, and an acoustic sensor and providing detected information;

a global positioning system (GPS) reception module providing the location information for the at least one buoy using a GPS signal;

a light indicator indicating a location of the at least one buoy; and

a control module processing a signal transmitted or received by a communication module and controlling an overall operation of the at least one buoy, wherein

each of the fishing vessel terminal device and the managing vessel terminal device includes the gateway device, a terminal, and an underwater acoustic tracker, wherein

the underwater acoustic tracker includes:

a serial interface (I/F) unit connected with the terminal using serial communication;

a transmission sensor transmitting an acoustic signal to the at least one buoy;

a reception sensor receiving an acoustic signal from the at least one buoy;

a multi-channel signal processing module detecting all information transmitted from the at least one buoy;

a multi-channel sound transmission module and a multi-channel sound reception module receiving a sound signal of a frequency band ranging from 5 Hz to 2,400 Hz at a certain depth, analyzing a strength and direction of the sound signal, multiplexing or demultiplexing the analyzed sound signal, and then transmitting the multiplexed or demultiplexed sound signal;

a control module receiving a communication option and the identification information for the at least one buoy from the terminal, transmitting, to the at least one buoy, the identification information according to the communication option, receiving the identification information for the at least one buoy and battery status information from the at least one buoy, and transmitting the received identification information and battery status information to the terminal; and

a battery providing power required for operating the underwater acoustic tracker, and wherein the gateway device measures the communication quality based on signal quality including a received signal strength indication (RSSI) or a signal-to-noise ratio (SNR) of a signal transmitted or received with the at least one buoy and sets the reference spreading factor based on the measured communication quality.

6. The maritime wireless communication method of claim 5 , further comprising:

before setting the reference spreading factor, forming a main communication channel through a public LoRa network for low-power, long-range communication and, in a shadow area, releasing the main communication channel with the public LoRa network and then forming a sub communication channel through a private LoRa network.

7. The maritime wireless communication method of claim 5 , wherein as the reference spreading factor increases, a spreading range and a data transmission speed of the gateway device increase.

8. The maritime wireless communication method of claim 5 , wherein as the reference spreading factor increases, a minimum SNR value and a data transmission rate of the gateway device decrease.