阅读说明：本技术 一种交通通信系统及方法 (Traffic communication system and method ) 是由 冯江华 张泰然 唐军 粟荡 全清华 王大君 蒋国涛 陆琦 周学勋 任懋华 于 2018-06-26 设计创作，主要内容包括：本发明公开了一种交通通信系统及方法,包括：位于地面的FSO基站,车载FSO,支持FSO通信的飞行设备,用户终端；所述车载FSO利用所述飞行设备与所述FSO基站建立通信连接；所述飞行设备的飞行速度和所述车载FSO载体的运行速度之差小于预设差值；所述用户终端通过所述车载FSO与所述FSO基站进行通信。本发明所提供的系统及方法,消除了车辆与地面基站之间FSO光链路的物体遮挡,从而扩大了车辆与地面间FSO的通信间距。(The invention discloses a traffic communication system and a method, comprising the following steps: the system comprises an FSO base station positioned on the ground, a vehicle-mounted FSO, flight equipment supporting FSO communication and a user terminal; the vehicle-mounted FSO establishes communication connection with the FSO base station by using the flight equipment; the difference between the flying speed of the flying equipment and the running speed of the vehicle-mounted FSO carrier is smaller than a preset difference value; and the user terminal communicates with the FSO base station through the vehicle-mounted FSO. The system and the method provided by the invention eliminate the object shielding of the FSO optical link between the vehicle and the ground base station, thereby enlarging the communication distance of the FSO between the vehicle and the ground.)

1. A traffic communication system, comprising: the system comprises an FSO base station positioned on the ground, a vehicle-mounted FSO, flight equipment supporting FSO communication and a user terminal;

the vehicle-mounted FSO establishes communication connection with the FSO base station by using the flight equipment;

the difference between the flying speed of the flying equipment and the running speed of the vehicle-mounted FSO carrier is smaller than a preset difference value;

and the user terminal communicates with the FSO base station through the vehicle-mounted FSO.

2. The traffic communication system of claim 1, wherein the flight device has two instances:

the first flight equipment enables the first vehicle-mounted FSO to be in communication connection with the Nth FSO base station by using the FSO communication technology;

the second flight equipment enables a second vehicle-mounted FSO to be in communication connection with the (N + 1) th FSO base station by using the FSO communication technology;

before the user terminal completes communication with the Nth FSO base station through the first vehicle-mounted FSO, link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 1) th FSO base station is completed;

and before the user terminal completes communication with the (N + 1) th FSO base station through the second vehicle-mounted FSO, completing link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 2) th FSO base station.

3. The traffic communication system of claim 2, wherein the first flight device utilizing FSO communications technology to connect the first on-board FSO with the nth FSO base station comprises:

when the user terminal needs to establish communication connection with the Nth FSO base station, the first lens of the first vehicle-mounted FSO emits laser to the first lens of the first flying device, so that the first lens of the first vehicle-mounted FSO is connected with the first flying device;

and the second lens of the first flight device is in link connection with the Nth FSO base station, so that the user terminal communicates with the Nth FSO base station through the first vehicle-mounted FSO.

4. The traffic communication system of claim 1, further comprising:

according to the time length required by charging of the flight equipment, the preset number of standby flight equipment in a charging standby state is set, and the standby flight equipment is used for replacing the flight equipment in a low-power state.

5. The traffic communication system of claim 4, comprising a first backup aerial device and a second backup aerial device;

when the electric quantity of the first flight device and the second flight device is lower than the preset threshold value, the first standby flight device and the second standby flight device are lifted from a charging area;

before the first flying device and the second flying device descend to the charging area, a first lens of the first standby flying device is connected with a second lens of the first vehicle-mounted FSO, and the second lens of the first standby flying device is connected with the Nth FSO base station;

and a first lens of the second standby flight device is connected with a second lens of the second vehicle-mounted FSO, and a second lens of the second standby flight device is connected with the (N + 1) th FSO base station.

6. The traffic communication system of claim 1, wherein the user terminal and the in-vehicle FSO are connected through a wireless access point.

7. The traffic communication system according to any one of claims 1 to 6, wherein the flying device automatically adjusts its flying height, angle and path using AI technology according to the current external factors.

8. A method for traffic communication, which is applied to a traffic communication system, comprises:

utilizing flight equipment supporting the FSO communication technology to enable the vehicle-mounted FSO and the FSO base station on the ground to establish communication connection;

the difference between the flying speed of the flying equipment and the running speed of the vehicle-mounted FSO carrier is smaller than a preset difference value;

and the user terminal communicates with the FSO base station through the vehicle-mounted FSO.

9. The method of claim 8, wherein the flight device has two hours:

the first flight equipment enables the first vehicle-mounted FSO to be in communication connection with the Nth FSO base station by using the FSO communication technology;

the second flight equipment enables a second vehicle-mounted FSO to be in communication connection with the (N + 1) th FSO base station by using the FSO communication technology;

before the user terminal completes communication with the Nth FSO base station through the first vehicle-mounted FSO, link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 1) th FSO base station is completed;

and before the user terminal completes communication with the (N + 1) th FSO base station through the second vehicle-mounted FSO, completing link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 2) th FSO base station.

10. The method of claim 9, wherein the first flight device connecting the first on-board FSO with the nth FSO base station using FSO communications technology comprises:

when the user terminal needs to establish communication connection with the Nth FSO base station, the first lens of the first vehicle-mounted FSO emits laser to the first lens of the first flying device, so that the first lens of the first vehicle-mounted FSO is connected with the first flying device;

and the second lens of the first flight device is in link connection with the Nth FSO base station, so that the user terminal communicates with the Nth FSO base station through the first vehicle-mounted FSO.

Technical Field

The present invention relates to the field of wireless communication, and in particular, to a traffic communication system and method.

Background

In the existing rail transit FSO communication scheme, the FSO on the train generally directly performs Line of Sight (LOS) communication with the FSO of the trackside ground base station. Due to the fact that the track is often bent (train turning) and the trackside environment is complex (tree leaves or telegraph poles), the situation that obstacles block the LOS of the train-ground FSO is easy to happen, so that the optical link is interrupted in receiving and transmitting, and stability of communication is affected. In order to realize continuous communication between a train and a ground base station, the existing scheme needs to erect a large number of dense base stations along a track to realize seamless coverage of the whole track, but excessively frequent roaming switching is also one of main factors which endanger the train to provide stable broadband internet service, because the train needs to continuously perform handshake negotiation and connection establishment with a new base station during the running process of the train, and the train-ground FSO has the risk of temporary communication interruption during the signal switching process, which undoubtedly has influence on continuous and stable wireless communication. The speed of the train is in direct proportion to the frequency of switching, so that high-speed trains (such as the renaissance number of 350km hour in China) are more likely to face the risks of unstable FSO communication performance and limited data rate.

In recent years, although some schemes for railway wireless communication have been proposed, the communication rate of the schemes is relatively limited, for example: the communication data rate of the train communication technology based on the leaky coaxial cable is too low (the maximum rate is 768kps), and the network communication bandwidth requirement of large data volume cannot be met at all. WiMax and WLAN-based architectures can only provide wireless communication below dozens of Mbps for trains. The technical means based on the satellite link is not suitable for providing multimedia broadband services for trains due to the problems of communication delay, speed, stability, cost and the like.

From the above, it can be seen that how to increase the FSO communication distance between the vehicle and the ground is a problem to be solved at present.

Disclosure of Invention

The invention aims to provide a traffic communication system and a traffic communication method, which solve the problem of overlarge base station density caused by short FSO communication distance between a train and the ground in the prior art.

To solve the above technical problem, the present invention provides a traffic communication system, including: the system comprises an FSO base station positioned on the ground, a vehicle-mounted FSO, flight equipment supporting FSO communication and a user terminal; the vehicle-mounted FSO establishes communication connection with the FSO base station by using the flight equipment; the difference between the flying speed of the flying equipment and the running speed of the vehicle-mounted FSO carrier is smaller than a preset difference value; and the user terminal communicates with the FSO base station through the vehicle-mounted FSO.

Preferably, the flight device has two times:

the first flight equipment enables the first vehicle-mounted FSO to be in communication connection with the Nth FSO base station by using the FSO communication technology;

the second flight equipment enables a second vehicle-mounted FSO to be in communication connection with the (N + 1) th FSO base station by using the FSO communication technology;

before the user terminal completes communication with the Nth FSO base station through the first vehicle-mounted FSO, link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 1) th FSO base station is completed;

and before the user terminal completes communication with the (N + 1) th FSO base station through the second vehicle-mounted FSO, completing link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 2) th FSO base station.

Preferably, the connecting the first onboard FSO with the nth FSO base station by the first flight device using the FSO communication technology includes:

when the user terminal needs to establish communication connection with the Nth FSO base station, the first lens of the first vehicle-mounted FSO emits laser to the first lens of the first flying device, so that the first lens of the first vehicle-mounted FSO is connected with the first flying device;

and the second lens of the first flight device is in link connection with the Nth FSO base station, so that the user terminal communicates with the Nth FSO base station through the first vehicle-mounted FSO.

Preferably, the method further comprises the following steps: according to the time length required by charging of the flight equipment, the preset number of standby flight equipment in a charging standby state is set, and the standby flight equipment is used for replacing the flight equipment in a low-power state.

Preferably, a first standby flight device and a second standby flight device are included;

when the electric quantity of the first flight device and the second flight device is lower than the preset threshold value, the first standby flight device and the second standby flight device are lifted from a charging area;

before the first flying device and the second flying device descend to the charging area, a first lens of the first standby flying device is connected with a second lens of the first vehicle-mounted FSO, and the second lens of the first standby flying device is connected with the Nth FSO base station;

and a first lens of the second standby flight device is connected with a second lens of the second vehicle-mounted FSO, and a second lens of the second standby flight device is connected with the (N + 1) th FSO base station.

Preferably, the user terminal and the vehicle-mounted FSO are connected through a wireless access point.

Preferably, the flying device automatically adjusts the flying height, angle and path of the flying device according to the current external factors by using an AI technology.

The invention also provides a traffic communication method, which is applied to a traffic communication system and comprises the following steps: utilizing flight equipment supporting the FSO communication technology to enable the vehicle-mounted FSO and the FSO base station on the ground to establish communication connection; the difference between the flying speed of the flying equipment and the running speed of the vehicle-mounted FSO carrier is smaller than a preset difference value; and the user terminal communicates with the FSO base station through the vehicle-mounted FSO.

Preferably, the flight device has two times:

the first flight equipment enables the first vehicle-mounted FSO to be in communication connection with the Nth FSO base station by using the FSO communication technology;

the second flight equipment enables a second vehicle-mounted FSO to be in communication connection with the (N + 1) th FSO base station by using the FSO communication technology;

before the user terminal completes communication with the Nth FSO base station through the first vehicle-mounted FSO, link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 1) th FSO base station is completed;

and before the user terminal completes communication with the (N + 1) th FSO base station through the second vehicle-mounted FSO, completing link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 2) th FSO base station.

Preferably, the connecting the first onboard FSO with the nth FSO base station by the first flight device using the FSO communication technology includes:

when the user terminal needs to establish communication connection with the Nth FSO base station, the first lens of the first vehicle-mounted FSO emits laser to the first lens of the first flying device, so that the first lens of the first vehicle-mounted FSO is connected with the first flying device;

and the second lens of the first flight device is in link connection with the Nth FSO base station, so that the user terminal communicates with the Nth FSO base station through the first vehicle-mounted FSO.

The traffic communication system provided by the invention comprises an FSO base station positioned on the ground, a vehicle-mounted FSO and flight equipment supporting FSO communication. The invention utilizes flight equipment supporting FSO communication technology to establish communication connection between the vehicle-mounted FSO and the FSO base station, so that the user terminal can perform communication connection between the vehicle-mounted FSO and the FSO base station. The traffic communication system provided by the invention utilizes the flight equipment to establish the communication connection between the vehicle-mounted FSO and the FSO base station, and eliminates the object shielding of the FSO optical link between the vehicle and the ground base station, thereby expanding the communication distance between the train and the ground FSO, reducing the erection quantity of the FSO base station along the track while avoiding frequent roaming switching between the vehicle and the ground, reducing the difficulty in building and maintaining the base station and saving the investment cost.

Drawings

In order to more clearly illustrate the embodiments or technical solutions of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

FIG. 1 is a flow chart of a first embodiment of a traffic communication system according to the present invention;

fig. 2 is a schematic structural diagram of a second embodiment of a traffic communication system according to the present invention;

fig. 3 is a schematic structural diagram of a traffic communication system according to a third embodiment of the present invention;

FIG. 4 is a schematic diagram of the traffic communication system in operation with the standby flight device;

fig. 5 is a flowchart of a traffic communication method according to an embodiment of the present invention.

Detailed Description

The core of the invention is to provide a traffic communication system and a method, which enlarge the FSO communication distance between a train and the ground.

In order that those skilled in the art will better understand the disclosure, the invention will be described in further detail with reference to the accompanying drawings and specific embodiments. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a traffic communication system according to a first embodiment of the present invention; the traffic communication system provided by the embodiment comprises: the system comprises an FSO base station positioned on the ground, a vehicle-mounted FSO, flight equipment supporting FSO communication and a user terminal. The difference between the flying speed of the flying equipment and the running speed of the vehicle-mounted FSO carrier is smaller than a preset difference value; i.e. the flying apparatus remains relatively stationary with the onboard FSO carrier over a range of speed differences.

The FSO (Free Space Optics) communication technology uses light with a higher carrier frequency as an information carrier to replace a radio frequency/microwave link, and is a very promising wireless communication technology. The high bandwidth of the spectrum has the advantages of high data rate, free and unlimited frequency spectrum exceeding 300GHz, high safety, easy deployment and the like. In this embodiment, the vehicle-mounted FSO, the FSO base station, and the flight device supporting FSO communication all have Acquisition, Tracking, and Alignment (ATP) functions, so as to satisfy the stability of an optical signal link between FSO transceiver ends in a motion state.

The vehicle-mounted FSO in the traffic communication system provided by the embodiment can be applied to a train traffic track, a bus traffic communication system and a taxi and other small cars; the system can provide wireless network service for passengers in vehicles such as trains, buses and taxis. In the present embodiment, a track traffic communication system of a train is taken as an example for specific description.

And respectively establishing communication connection with the vehicle-mounted FSO and the FSO base station by using flight equipment supporting an FSO communication technology so as to facilitate the communication connection between the vehicle-mounted FSO and the FSO base station, thereby enabling the user terminal on the train to communicate with the FSO base station through the vehicle-mounted FSO. And the wireless access point on the train is used for relaying data between the FSO base station and the user mobile terminal. As the train travels along the track, only the rooftop FSO transceiver needs to perform the base station handoff process, while the user in the train is always within the coverage of the wireless access point.

In this embodiment, the flight device may be based on factors such as the speed of train travel, the surrounding terrain environment, and weather conditions; the flying height, angle, path and the like of the aircraft are automatically adjusted by utilizing the technologies such as AI and the like, so that the electric quantity distribution is optimized and the flying obstacle is avoided while the ATP is ensured to capture and align the optical signals and the FSO is normally and stably communicated.

The flight device can be an Unmanned Aerial Vehicle (UAV) supporting the FSO communication technology or other devices with flight suspension functions.

Due to the different energy supply devices of the flight devices, the number of flight devices required in the traffic system also varies. In this embodiment, the flying apparatus can be regarded as a flying apparatus having a sustainable energy supply device, such as solar energy, wind energy, or a combination of multiple energy supplies to provide endurance for the flying apparatus.

The traffic communication system provided by the embodiment uses the flight equipment supporting the FSO communication as the bridge between the vehicle-mounted FSO and the FSO base station, and utilizes the characteristics that the flight equipment is located at high altitude, and has a good view and no obstruction in the LOS range. Therefore, the communication distance between the FSO base station located on the ground and the vehicle-mounted FSO can be effectively enlarged, thereby effectively enlarging the arrangement distance between the FSO base stations on the ground. And with the improvement of flying height and ATP precision, the distance between the FSO base stations has further expanded space, so that the number of the FSO base stations along the track is greatly reduced, and the difficulty of base station construction and maintenance and the investment cost are reduced.

Based on the above embodiment, when the flight device is a flight device capable of supplying energy continuously, in order to enable the traffic communication system provided in this embodiment to still achieve seamless base station switching when the flight device fails, eliminate the influence of switching delay on user terminal communication, and ensure continuity of communication, at least two flight devices supporting FSO are provided in the traffic communication system. Referring to fig. 2, fig. 2 is a schematic structural diagram of a traffic communication system according to a second embodiment of the present invention.

In this embodiment, the flying apparatus and the onboard FSO have at least two lenses, one of which is used for alignment communication with the onboard FSO and the other of which is used for alignment communication with the FSO base station located on the ground.

When the number of the flight devices is two, when the user terminal needs to establish communication connection with the Nth FSO base station, the first lens of the first vehicle-mounted FSO emits laser to the first lens of the first flight device, so that the first lens of the first vehicle-mounted FSO is connected with the first lens of the first flight device; and the second lens of the first flight device is in link connection with the Nth FSO base station, so that the user terminal communicates with the Nth FSO base station through the first vehicle-mounted FSO.

When the user terminal needs to establish communication connection with the (N + 1) th FSO base station, the first lens of the second vehicle-mounted FSO emits laser to the first lens of the second flight device, so that the first lens of the second vehicle-mounted FSO is connected with the first lens of the second flight device; and a second lens of the second flight device is in link connection with the (N + 1) th FSO base station, so that the user terminal communicates with the (N + 1) th FSO base station through the second vehicle-mounted FSO.

It should be noted that, in addition to the connection relationship between the vehicle-mounted FSO and the flying apparatus through the laser and the connection relationship between the flying apparatus and the FSO base station through the laser, the vehicle-mounted FSO, the flying apparatus, and the FSO base station may also establish a communication link through visible light transmission.

Before the user terminal completes communication with the Nth FSO base station through the first vehicle-mounted FSO, link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 1) th FSO base station is completed; and before the user terminal completes communication with the (N + 1) th FSO base station through the second vehicle-mounted FSO, completing link connection between the second flight equipment and the second vehicle-mounted FSO and the (N + 2) th FSO base station, and repeating the steps in a circulating manner.

The traffic communication system provided by the embodiment at least comprises two flight devices supporting FSO communication and at least two vehicle-mounted FSOs, and seamless base station switching can be realized, so that a train is ensured to obtain continuous and stable communication service in the running process.

Based on the above embodiment, in this embodiment, if the flight device is a chargeable flight device, in order to implement a communication link for seamless handover, the traffic communication system provided in this embodiment further includes a preset number of standby flight devices for replacing flight devices in a low-battery state, in addition to the specific two flight devices. The number of the standby flight devices can be set according to the time length required by charging the flight devices. Referring to fig. 3 and fig. 4, fig. 3 is a schematic structural diagram of a traffic communication system according to a third embodiment of the present invention; fig. 4 is a schematic structural diagram of a traffic communication system when the standby flight device is in operation.

In the present embodiment, two spare flying devices are provided. When the electric quantity of the first flight device and the second flight device is lower than the preset threshold value, the first standby flight device and the second standby flight device are lifted from a charging area; before the first flying device and the second flying device descend to the charging area, a first lens of the first standby flying device is connected with a second lens of the first vehicle-mounted FSO, and the second lens of the first standby flying device is connected with the Nth FSO base station; and a first lens of the second standby flight device is connected with a second lens of the second vehicle-mounted FSO, and a second lens of the second standby flight device is connected with the (N + 1) th FSO base station.

Since the distance between the base stations is greatly expanded, the train and one base station need to keep long-time communication, but in order to realize seamless base station switching, the flight device in the embodiment, which needs to reduce the switching times as much as possible, is a chargeable flight device. Therefore, the traffic communication system provided in this embodiment at least includes two flight devices, two vehicle-mounted FSOs, and a preset number of standby flight devices; therefore, the problems of overhead, delay, rate and the like caused by frequent switching are effectively solved, and the communication performances of reliability, continuity, high rate and the like of communication are ensured.

The traffic communication system provided by the embodiment eliminates the object shielding of the FSO optical link between the train and the ground base station, thereby enlarging the communication distance of the FSO between the train and the ground; the method has the advantages that frequent roaming switching between vehicles and the ground is avoided, the number of FSO base stations along the track is reduced, the difficulty in building and maintaining the base stations is reduced, and the investment cost is saved.

Referring to fig. 5, fig. 5 is a flowchart illustrating a traffic communication method according to an embodiment of the present invention; the specific operation steps are as follows:

step S501: utilizing flight equipment supporting the FSO communication technology to enable the vehicle-mounted FSO and the FSO base station on the ground to establish communication connection; the difference between the flying speed of the flying equipment and the running speed of the vehicle-mounted FSO carrier is smaller than a preset difference value;

step S502: and the user terminal communicates with the FSO base station through the vehicle-mounted FSO.

The traffic communication method provided in this embodiment is used to implement the traffic communication system, and therefore, the specific implementation manner of the traffic communication method can be found in the embodiment section of the traffic communication system in the foregoing, and is not described herein again.

The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same or similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

The traffic communication system and method provided by the invention are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.