WO2019076296A1

WO2019076296A1 - Wireless communication system

Info

Publication number: WO2019076296A1
Application number: PCT/CN2018/110415
Authority: WO
Inventors: 黄永江
Original assignee: 北京凤凰汇通科技有限公司
Priority date: 2017-10-20
Filing date: 2018-10-16
Publication date: 2019-04-25
Also published as: CN107528609A; CN107528609B

Abstract

The embodiments of the present invention relate to a wireless communication system, comprising a wireless communication array and a wireless signal transceiving chain. The wireless communication array comprises a first array optical fibre, an optical divider and a plurality of wireless communication nodes, wherein the first array optical fibre transmits a first signal optical signal; the optical divider performs division processing on the first signal optical signal to obtain a divided optical signal; and the wireless communication nodes simultaneously and synchronously send first pulse signals. The wireless signal transceiving chain comprises a synchronous controller, a first signal optical fibre, a plurality of first passive optical splitters, a plurality of wireless signal transceiving nodes, a plurality of second passive optical splitters and a second signal optical fibre, wherein the synchronous controller generates a receiving control instruction and sends same to a current wireless signal transceiving node; and the current wireless signal transceiving node generates a first communication optical signal according to a first pulse signal.

Description

Wireless communication system

This application claims priority to Chinese Patent Application, filed on Oct. 20, 2017, filed Jan.

Technical field

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

Background technique

So far, all mobile communication systems have been established to solve personal communications. Therefore, from the first generation of mobile communication systems to today's 5G mobile communication systems, all mobile communication technologies are developed to improve the quality of personal communication. Therefore, it is unrealistic to attempt to establish a vehicle-to-ground communication of a high-speed train under wide-area conditions on the existing technology of mobile communication or existing infrastructure. In fact, the current GSM-R evolved from GSM technology has become increasingly incapable of adapting to the increasingly urgent information and intelligent vehicle-to-ground communication needs of high-speed railway traffic, and it has not seen the effective progress of this technology. And the technical progress of the high-speed rail vehicle communication system.

Due to the high-speed mobile condition, wireless communication is first affected by the Doppler effect. As the radio frequency increases with the moving speed, the frequency offset phenomenon will also increase synchronously, which not only causes frequency out-of-synchronization but also under high-density signal modulation. Broadband wireless communication also introduces significant signal out-of-synchronization, and the radio receiver cannot resolve the communication signals sent by the transmitter.

Under high-speed mobile conditions, the multipath fading of wireless communication, especially wireless broadband communication, is dramatically amplified. The direct communication path is destroyed by high-speed movement and replaced by many unpredictable communication paths. These phenomena directly lead to multipath fading under high-speed movement. The main reason for the apparent increase. This phenomenon is particularly prominent in the high-power long-distance wireless communication mode.

In order to achieve the purpose of wireless communication, especially wireless broadband communication under high-speed conditions, it is common practice to construct a base station and increase communication and power along a high-speed railway line, and this method reduces the reliability of wireless communication. Long-distance wireless communication due to climate change reasons such as rain, snow, fog and other severe weather phenomena will not only reduce the quality of wireless communication, and even interrupt communication, so wireless communication will lose the important support means of high-speed railway information and intelligence. The status will directly lead to the failure of high-speed railway informationization and intelligence.

Similarly, although wireless optical communication is not affected by the Doppler effect, the requirements for meteorological conditions are too high and the high complexity of the system is not yet possible. However, the possibility of applying this technology to high-speed rail communication is not seen, and satellite communication In addition to the limitations of communication bandwidth, satellite signals in the high latitudes are too weak and too many railway tunnels are the main reasons for limiting the use of satellite communications in high-speed rail vehicles.

Summary of the invention

The object of the present invention is to provide a wireless communication system for a wireless communication system, and to provide a novel wireless communication mode, which applies a millimeter wave communication technology to communicate with a vehicle to solve a communication bandwidth, and uses a short distance micro power. Wireless communication technology replaces long-distance high-power communication to solve the reliability problem of wireless communication, and replaces the high-density signal modulation technology commonly used in wireless broadband communication with the direct modulation method of wireless optical communication to achieve signal synchronization and frequency synchronization under high-speed mobile conditions. Thus, the present invention combines millimeter wave communication technology and optical communication technology, and uses a dedicated communication protocol to realize high-capacity, high-reliability data communication of the vehicle under high-speed moving conditions.

In view of this, an embodiment of the present invention provides a wireless communication system, where the wireless communication system includes: a wireless communication group and a wireless signal transceiving chain;

The wireless communication group column includes: a first group of column fibers, an optical splitter, and a plurality of wireless communication nodes;

The first set of column fibers for transmitting a first signal light signal;

The optical splitter is configured to perform split processing on the first signal optical signal to obtain multiple identical split optical signals;

The plurality of wireless communication nodes are configured to synchronously generate the same first pulse signal according to the split optical signal, whereby each wireless communication node of the wireless communication group simultaneously transmits the first pulse signal simultaneously;

The wireless signal transceiving chain includes: a synchronization controller, a first signal fiber, a plurality of first passive optical splitters, a plurality of wireless signal transceiving nodes, a plurality of second passive optical splitters, and a second signal optical fiber;

The synchronization controller is configured to generate a receiving control command, and send, by using the first signal fiber and the first passive optical splitter, a plurality of wireless signals corresponding to the first passive optical splitter and requiring receiving a pulse signal a current wireless signal transceiving node in the transceiver node;

The current wireless signal transceiving node is configured to receive a first pulse signal that is simultaneously sent by a plurality of wireless communication nodes of the wireless communication group, and generate a first communication optical signal according to the first pulse signal;

The second passive optical splitter is configured to receive a first communication optical signal sent by a corresponding wireless signal transceiver node, and send the signal to the second signal fiber.

Preferably, after the current wireless signal transceiver node receives the first pulse signal, the synchronization controller is further configured to generate a reception stop command, and send the signal to the current wireless signal transceiver node, the wireless signal transceiver node. Stop receiving the first pulse signal.

Further preferably, the synchronization controller is further configured to generate a connection receiving command, and send the connection to the connection wireless signal transceiver node of the current wireless signal transceiver node;

The connecting wireless signal transceiving node starts receiving a first pulse signal simultaneously sent by the plurality of wireless communication nodes, and generates a first communication optical signal;

The second passive optical splitter is configured to receive a first communication optical signal that is sent by the connection wireless signal transceiver node and send the signal to the second signal fiber.

Further preferably, the wireless signal transceiver chain further includes:

The second optical communication device is connected to the second signal fiber for processing the first communication optical signal sent by the second signal fiber.

Preferably, the wireless communication node includes: a first photoelectric converter, a first frequency generator, a first modulator, a first power amplifier, and a first antenna;

The first photoelectric converter is configured to receive a split optical signal sent by the optical splitter, convert the split optical signal into a first electrical signal, and send the signal to the first modulator;

The first frequency generator is configured to generate a frequency signal and send the signal to the first modulator;

The first modulator is configured to modulate the first electrical signal into the frequency signal, generate a first synchronous driving signal, and send the first synchronous driving signal to the first power amplifier;

The first power amplifier is configured to amplify the first synchronous driving signal to generate an amplified first synchronous driving signal;

The first antenna is configured to send a first pulse signal according to the amplified first synchronous driving signal.

Further preferably, the wireless signal transceiving node comprises: a second antenna, a low noise amplifier, a mixer, a second frequency generator, a limiting amplifier, a second modulator and a second photoelectric converter;

The second antenna is configured to receive a first pulse signal that is sent by multiple wireless communication nodes of the wireless communication group;

The low noise amplifier is configured to perform low noise amplification processing on the first pulse signal received by the second antenna, generate a processing pulse signal, and send the signal to the mixer;

The second frequency generator is configured to generate a frequency signal and send the signal to the mixer;

The mixer is configured to process the frequency signal into a mixed electrical signal according to the processing pulse signal;

The limiting amplifier is configured to perform a limiting amplification process on the mixed electrical signal to generate an amplified electrical signal;

The second modulator is configured to perform protocol conversion on the amplified electrical signal to generate a first communication electrical signal;

The second photoelectric converter is configured to convert the first communication electrical signal into a first communication optical signal.

Further preferably, the wireless signal transceiving node further includes a second power amplifier;

The first signal fiber is further configured to transmit a second signal optical signal;

The plurality of first passive optical splitters are respectively configured to process the second signal optical signal transmitted by the first signal fiber to obtain a branched optical signal;

The second photoelectric converter is further configured to receive the branch optical signal corresponding to the first passive optical splitter, convert the branched optical signal into a second electrical signal, and send the second optical signal to the second modulator;

The second frequency generator is further configured to generate a frequency signal and send the signal to the second modulator;

The second modulator is further configured to receive a synchronous transmission command sent by the synchronization controller, and modulate the second electrical signal into the frequency signal according to the synchronous transmission instruction to generate a second synchronous driving signal, And sent to the second power amplifier;

The second power amplifier is further configured to amplify the second synchronous driving signal to generate an amplified second synchronous driving signal;

The second antenna is further configured to send a second pulse signal according to the second synchronous driving signal, so that each wireless signal transceiving node of the wireless signal transceiving chain simultaneously transmits the same synchronously under the control of the synchronous controller The second pulse signal.

Further preferably, the wireless communication group column includes a signal processor, and is respectively connected to the plurality of wireless communication nodes;

Each of the plurality of wireless communication nodes is further configured to receive a second pulse signal sent by the wireless signal transceiving node;

The first modulator is further configured to demodulate the second pulse signal to generate a second communication electrical signal;

The first photoelectric converter is further configured to generate a second communication optical signal corresponding to the second communication electrical signal generated by the first demodulator;

The signal processor is configured to respectively receive a second communication optical signal sent by each of the wireless communication nodes, and perform filtering processing to receive the optical signal.

Further preferably, the wireless communication group column further includes:

A second set of column fibers coupled to the signal processor for transmitting a received optical signal transmitted by the signal processor.

Further preferably, the wireless communication group column further includes:

a first optical communication device coupled to the second set of column fibers for processing received optical signals transmitted by the second set of columns of fibers.

A wireless communication system provided by an embodiment of the present invention provides a brand-new wireless communication mode, which applies a millimeter wave communication technology to communicate with a vehicle to solve a communication bandwidth, and replaces a long distance with a short-distance micro-power wireless communication technology. Power communication solves the reliability problem of wireless communication, and replaces the high-density signal modulation technology commonly used in wireless broadband communication with the direct modulation method of wireless optical communication to achieve signal synchronization and frequency synchronization under high-speed moving conditions; thus, the present invention combines Millimeter wave communication technology and optical communication technology, and use a dedicated communication protocol to realize large-capacity, high-reliability data communication of vehicles under high-speed moving conditions.

DRAWINGS

1 is a schematic structural diagram of a wireless communication group column according to an embodiment of the present invention;

2 is a schematic structural diagram of a wireless communication node according to an embodiment of the present invention;

3 is a schematic diagram of a wireless communication node transmitting a signal according to an embodiment of the present invention;

4 is a schematic structural diagram of a wireless signal transceiving chain according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a wireless signal sending and receiving node according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a signal received by a wireless signal transceiving node according to an embodiment of the present invention.

Detailed ways

The technical solution of the present invention will be further described in detail below through the accompanying drawings and embodiments.

The wireless communication system provided by the embodiment of the present invention includes a wireless communication group column and a wireless signal transmission and reception chain.

First, the structure of the wireless communication group column is introduced. FIG. 1 is a schematic structural diagram of a wireless communication group column according to an embodiment of the present invention. As shown in FIG. 1 , the wireless communication group includes a first group of column fibers 11 and an optical splitter. 12 and a plurality of wireless communication nodes 13. It should be noted that, in the communication process, the wireless communication group column can transmit signals to the wireless signal transmission and reception chain, and can also receive signals transmitted by the wireless signal transmission and reception chain.

The first group of optical fibers 11 is configured to transmit the first signal optical signal; specifically, the first group of columns of optical fibers 11 transmit optical signals, and the first signal optical signals refer to the wireless communication group for transmission to the wireless signal transceiving chain. signal of.

The optical splitter 12 is connected to the first set of column fibers 11, so that the optical splitter 12 can receive the signal optical signals transmitted by the first set of columns of optical fibers 11, and the optical splitter 12 transmits the first set of columns of optical fibers 11. The first signal optical signal is subjected to shunt processing to obtain multiple identical split optical signals; and the optical splitter 12 is connected to the plurality of wireless communication nodes 13, and each of the branched optical signals is separately sent to one wireless communication. The node 13 thus realizes that the signal optical signal is transmitted downward in the form of a broadcast, so that the branched optical signal received at each wireless communication node 13 is the same.

The plurality of wireless communication nodes 13 synchronously generate the same first pulse signal according to the split optical signal, whereby each wireless communication node 13 of the wireless communication group simultaneously simultaneously transmits the first pulse signal. 2 is a schematic structural diagram of a wireless communication node 13 according to an embodiment of the present invention. The structure of the wireless communication node 13 is specifically described below. As shown in FIG. 2, the wireless communication node 13 includes a first photoelectric converter 131 and a first frequency generator. 132. A first modulator 133, a first power amplifier 134, and a first antenna 135.

FIG. 3 is a schematic diagram of a wireless communication node transmitting a signal according to an embodiment of the present invention. When the wireless communication node 13 transmits a signal, the first photoelectric converter 131 is configured to receive the optical splitter 12 and send the signal according to FIG. 2 and FIG. 3. The split optical signal converts the split optical signal into a first electrical signal, thereby completing the conversion process of the optical signal to the electrical signal, and transmitting the signal to the first modulator 133, wherein the waveform of the split optical signal can be in FIG. The waveform diagram shown in the lower left of the first photoelectric converter 131, the waveform diagram of the first electrical signal formed by photoelectric conversion may be the waveform diagram shown at the upper left of the first photoelectric converter 131.

The first frequency generator 132 is configured to generate a frequency signal, which is sent to the first modulator 133. Specifically, the frequency generator is capable of generating a frequency signal of a stable waveform for the modulator to perform a carrier, wherein the first frequency generator 132 generates The frequency signal waveform diagram may be the waveform diagram shown at the upper left of the first frequency generator 132 in FIG.

The first modulator 133 modulates the first electrical signal into the frequency signal, that is, loads the first electrical signal into the frequency signal of the stable waveform, generates a first synchronous driving signal, and sends the first synchronous driving signal to the first power amplifier 134, wherein The waveform diagram of the first synchronous driving signal may be the waveform diagram shown at the upper left of the first modulator 133 in FIG. 3; the modulation mode of the modulator is a pulse modulation method, such as on-off keying modulation (OOK). Or digital pulse interval modulation (DPIM) or the like.

The first power amplifier 134 is configured to amplify the first synchronous driving signal to generate an amplified first synchronous driving signal. Specifically, since the waveform of the first synchronous driving signal generated by the first modulator 133 is small, the first power is required. The amplifier 134 amplifies the first synchronous drive signal to obtain a waveform-amplified first synchronous drive signal.

The first antenna 135 is configured to send the first pulse signal according to the amplified first synchronous driving signal. The first antenna 135 is preferably a radio frequency antenna. Specifically, the first antenna is generated according to the first power amplifier 134. The driving signal generates a first pulse signal of micro power, and the first pulse signal of the micro power may be a radio frequency signal and sent to the wireless signal transceiving chain.

Next, the structure of the wireless signal transceiving chain is introduced. FIG. 4 is a schematic structural diagram of a wireless signal transceiving chain according to an embodiment of the present invention. As shown in FIG. 4, the radio signal transceiving chain includes a synchronization controller 23, a first signal fiber 21, and more. The first passive optical splitter 22, the plurality of wireless signal transceiving nodes 24, the plurality of second passive optical splitters 25, and the second signal optical fibers 26. It should be noted that the wireless signal transmission and reception chain may be connected to the wireless communication group or receive the signal transmitted by the wireless communication group.

The synchronization controller 23 is configured to generate a receiving control command, and send the first signal optical fiber 21 and the first passive optical splitter 22 to the plurality of wireless corresponding to the first passive optical splitter 22 and need to receive the pulse signal. The current wireless signal transceiving node 24 in the signal transceiving node 24.

The current wireless signal transceiving node 24 is configured to receive a first pulse signal that is simultaneously sent by the plurality of wireless communication nodes 13 of the wireless communication group, and generate a first communication optical signal according to the first pulse signal; The node refers to the wireless signal transceiving node in the working state, and the wireless signal transceiving node in each working state can be referred to as the current wireless signal transceiving node, and the structure of each wireless signal transceiving node is the same.

FIG. 5 is a schematic structural diagram of a wireless signal transceiving node according to an embodiment of the present invention. The structure of a radio signal transceiving node is specifically described below. As shown in FIG. 5, the radio signal transceiving node 24 includes a second antenna 245, a low noise amplifier 246, and a hybrid The frequency converter 247, the second frequency generator 242, the limiting amplifier 248, the second modulator 243, and the second photoelectric converter 241.

As shown in FIG. 5 and FIG. 6, when the wireless signal transceiving node 24 receives the signal, the second antenna 245 is configured to receive the first pulse signal simultaneously transmitted by the first antenna 135 of the plurality of wireless communication nodes 13 of the wireless communication group. That is, the signal transmission between the wireless communication group and the wireless signal transceiving chain is transmitted by the radio frequency signal generated by the antenna; wherein the waveform of the first pulse signal received by the second antenna 245 can be as shown in FIG. A waveform diagram on the left side of the second antenna 245.

The low noise amplifier 246 is configured to perform low noise amplification processing on the first pulse signal received by the second antenna 245, generate a processing pulse signal, and send the signal to the mixer 247; the waveform of the processed pulse signal may be low noise as shown in FIG. Waveform at the top right of amplifier 246.

The second frequency generator 242 is configured to generate a frequency signal and send the signal to the mixer 247. Specifically, the second frequency generator 242 can generate a frequency signal of the stable waveform for the carrier 247 to perform carrier frequency, wherein the frequency signal The waveform may be a waveform diagram at the upper left of the second frequency generator 242 as in FIG.

The mixer 247 is configured to process the frequency signal into a mixed electrical signal according to the processed pulse signal; specifically, the mixer 247 loads the processed pulse signal into a frequency signal having a stable waveform, thereby obtaining a mixed signal, and transmitting the signal to the mixed signal. The limiting amplifier 248, wherein the waveform diagram of the obtained mixing signal can be a waveform diagram of the upper right of the mixer 247 in FIG.

The limiting amplifier 248 is configured to perform a limiting amplification process on the mixed electrical signal to generate an amplified electrical signal. Specifically, since the mixed signal generated by the mixer 247 has a small waveform, the limiting amplifier 248 is required to perform the mixed signal. The amplification process is performed to obtain a waveform-amplified electrical signal, which is sent to the second modulator 243. The waveform of the amplified electrical signal can be a waveform diagram as shown in the upper right of the limiting amplifier 248 of FIG.

The second modulator 243 is configured to perform protocol conversion on the amplified electrical signal to generate a first communication electrical signal; the waveform diagram of the first communication electrical signal may be a waveform diagram as shown in the upper right of the second modulator 243 in FIG.

The second photoelectric converter 241 is configured to convert the first communication electrical signal into the first communication optical signal, thereby converting the transmitted electrical signal into an optical signal.

After the current wireless signal transceiver node receives the first pulse signal, the synchronization controller 23 is further configured to generate a reception stop command, and send the signal to the current wireless signal transceiver node, and the wireless signal transceiver node stops receiving the first pulse signal. The synchronization controller 23 is further configured to generate a connection receiving command, and send the connection to the connection wireless signal transceiver node of the current wireless signal transceiver node; the connection wireless signal transceiver node starts to receive the first pulse signal simultaneously sent by the plurality of wireless communication nodes 13 to generate the first Communication optical signal.

A plurality of second passive optical splitters 25 are respectively connected to the wireless signal transceiving node 24, that is, each wireless signal transceiving node 24 corresponds to a second passive optical splitter 25, and the second passive optical splitter 25 is used. The first communication optical signal generated by the corresponding connection wireless signal transceiver node 24 is received and sent to the second signal fiber 26.

The wireless signal receiving chain further includes a second optical communication device 27 coupled to the second signal fiber 26 for processing the first communication optical signal transmitted by the second signal fiber 26.

In the process of the wireless signal transceiving chain emitting a signal to the wireless communication group, the synchronization controller 23 is further configured to generate a synchronous transmission signal and send it to all the wireless signal transceiving nodes 24, and all the wireless signal transceiving nodes 24 are synchronized according to the communication protocol specified by the system. The second pulse signal of the same frequency and synchronized in time is emitted, whereby each of the wireless signal transceiving nodes 24 of the wireless signal transceiving chain simultaneously simultaneously transmits the same second pulse signal under the control of the synchronizing controller 23.

Specifically, as shown in FIG. 4 again, the first signal fiber 21 can also be used to transmit a second signal optical signal, wherein the first signal fiber 21 transmits an optical signal, and the second signal optical signal refers to a wireless signal transmission chain. The signal to be sent to the wireless communication group column.

The plurality of first passive optical splitters 22 are respectively connected to the first signal fiber 21, and the second signal optical signal transmitted by the first signal fiber 21 is processed to obtain multiple identical branched optical signals, and sent to corresponding ones. The wireless signal transceiving node 24, thereby realizing the signal optical signal to be transmitted downward in the form of a broadcast, so that the branched optical signals received at each of the wireless signal transmitting and receiving nodes 24 are the same.

As shown in FIG. 4 and FIG. 5, the second photoelectric converter 241 of each wireless signal transceiver node 24 can also be configured to receive a branch optical signal corresponding to the first passive optical splitter 22, and convert the branched optical signal into a first optical signal. The second electrical signal, thereby completing the conversion process of the optical signal to the electrical signal, is sent to the second modulator 243.

The second frequency generator 242 can also be used to generate a frequency signal for transmission to the second modulator 243; in particular, the frequency generator can generate a frequency signal of the stable waveform for the modulator to carry out the carrier. The second modulator 243 is further configured to receive the synchronous transmission command sent by the synchronization controller 23, modulate the second electrical signal into the frequency signal according to the synchronous transmission instruction, generate the second synchronous driving signal, and send the second synchronous driving signal to the second power amplifier 244. Wherein, the modulation mode of the modulator is a pulse modulation method, such as OOK or DPIM.

The second power amplifier 244 can also be used to amplify the second synchronous driving signal to generate an amplified second synchronous driving signal. Specifically, since the waveform of the second synchronous driving signal generated by the second modulator 243 is small, a second is required. The power amplifier 244 amplifies the second synchronous drive signal to obtain a waveform-amplified second synchronous drive signal.

The second antenna 245 is further configured to send the second pulse signal according to the second synchronous driving signal, and the second antenna 245 is preferably a radio frequency antenna. Specifically, the radio frequency antenna is generated according to the amplified second driving signal generated by the second power amplifier 244. The second pulse signal of the micro power, the second pulse signal of the micro power may be a radio frequency signal and sent to the wireless communication group column.

The first antenna 135 of the plurality of wireless communication nodes 13 can also be used to receive the second pulse signal transmitted by the wireless signal transceiving node 24 in the wireless signal transceiving chain.

Again, as shown in FIG. 1, the wireless communication group column further includes a signal processor 14, which may be a chip, respectively connected to a plurality of wireless communication nodes 13, for generating the same for a plurality of wireless communication nodes 13. The communication optical signal is filtered.

Specifically, in conjunction with FIG. 1 and FIG. 2, the first modulator 133 is further configured to demodulate the second pulse signal to generate a second communication electrical signal; the first photoelectric converter 131 is further configured to use the corresponding first solution. The second communication electrical signal generated by the modulator generates a second communication optical signal. The signal processor 14 is configured to respectively receive the second communication optical signal transmitted by each of the wireless communication nodes 13, and perform filtering processing to receive the optical signal. The wireless communication group column further includes a second set of column fibers 15 coupled to the signal processor 14 for transmitting the received light signals transmitted by the signal processor 14. The wireless communication group column further includes a first optical communication device 16 coupled to the second set of column fibers 15 for processing the received optical signals transmitted by the second set of column fibers 15.

The wireless communication system provided by the present invention can be specifically applied to vehicle-to-ground communication. Specifically, the distribution of the wireless communication group and the wireless signal transmission and reception chain are parallel, and the wireless communication group is installed on the carriage along the longitudinal axis of the train. The wireless communication nodes 13 form a linear radio coverage area by a combination of antennas or antennas; the wireless signal transceiving chain is arranged along the direction of the train track, and the plurality of wireless signal transceiving nodes 24 are connected by a passive optical network to form a chain type wireless network. The antenna of each wireless signal transceiver node 24 is perpendicular to the rail and opposite to the antenna direction of the wireless communication node 13, and the distance ensures that the mutually transmitted wireless signals can be completely accepted by the other party, thereby forming a wireless communication relationship; wherein, the line type The length of the wireless communication group column is L, the distance between each wireless signal transceiving node 24 of the wireless signal transceiving chain is equal, and is equal to the length L of the linear wireless communication group column. The following describes the communication process between the in-vehicle wireless communication group and the ground wireless signal transmission and reception chain.

When the train communicates to the ground, the vehicle-to-ground communication mainly includes two parts, one is the in-vehicle wireless communication group column transmitting signal, and the other is the wireless signal receiving and receiving chain receiving signal.

When the signal is transmitted in the in-vehicle wireless communication group, the first signal light signal sent by the train signal processing system end is transmitted along the first group of columns of optical fibers 11, and is divided into N channels of the same split optical signal by the optical splitter 12. The N-channel identical split optical signals are respectively transmitted along the first set of column fibers 11 to the corresponding wireless communication nodes 13, and the photoelectric converter of each wireless communication node 13 receives a split optical signal transmitted by the optical splitter 12. The synchronization controller 23 is configured to send synchronization control signals to all the wireless communication nodes 13, and control all the wireless communication nodes 13 to synchronously issue the same frequency and the first pulse signals synchronized in time according to the communication protocol specified by the system.

Specifically, the first photoelectric converter 131 of each wireless communication node 13 receives the split optical signal sent by the optical splitter 12, converts the split optical signal into a first electrical signal, thereby completing the conversion of the optical signal to the electrical signal. The process is sent to the first modulator 133. The first frequency generator 132 generates a frequency signal that is sent to the first modulator 133; in particular, the frequency generator is capable of generating a frequency signal of a stable waveform for the modulator to carry out the carrier. The first modulator 133 modulates the first electrical signal into the frequency signal, that is, loads the first electrical signal into the frequency signal of the stable waveform, generates a first synchronous driving signal, and sends the first synchronous driving signal to the first power amplifier 134; The modulation mode of the modulator is a pulse modulation method such as OOK or DPIM. The first power amplifier 134 amplifies the first synchronous driving signal to generate an amplified first synchronous driving signal. Specifically, since the waveform of the first synchronous driving signal generated by the first modulator 133 is small, the first power amplifier 134 is required. The first synchronous drive signal is amplified to obtain a waveform that significantly amplifies the first synchronous drive signal. The first antenna 135 transmits the first pulse signal according to the amplified first synchronous driving signal. The first antenna 135 is preferably a radio frequency antenna. Specifically, the radio frequency antenna generates the amplified first synchronous driving signal generated by the first power amplifier 134. The first pulse signal of the micro power, the first pulse signal of the micro power may be a radio frequency signal and sent to the wireless signal transceiving chain. Thereby, each wireless communication node 13 of the wireless communication group is simultaneously synchronized to transmit the first pulse signal.

When the wireless signal receiving and receiving chain receives the signal, the synchronization controller 23 generates a receiving control command, which is sent to the first passive optical splitter 22 through the first signal fiber 21 and the first passive optical splitter 22, and needs to be received. The current wireless signal transceiving node 24 of the plurality of wireless signal transceiving nodes 24 of the pulse signal. The current wireless signal transceiving node 24 receives the first pulse signal simultaneously transmitted by the plurality of wireless communication nodes 13 of the wireless communication group, and generates a first communication optical signal according to the first pulse signal.

Specifically, the second antenna 245 of the current wireless signal transceiving node 24 receives the first pulse signal simultaneously transmitted by the first antenna 135 of the plurality of wireless communication nodes 13 of the wireless communication group, that is, the wireless communication group and the wireless signal. The signal transmission between the transceiver chains is transmitted through the RF signals generated by the antenna. The low noise amplifier 246 performs low noise amplification processing on the first pulse signal received by the second antenna 245, generates a processed pulse signal, and transmits it to the mixer 247. The second frequency generator 242 generates a frequency signal that is sent to the mixer 247; specifically, the second frequency generator 242 is capable of generating a frequency signal of the stable waveform for the mixer 247 to carry the carrier. The mixer 247 processes the frequency signal into a mixed electrical signal according to the processed pulse signal; specifically, the mixer 247 loads the processed pulse signal into a frequency signal having a stable waveform, thereby obtaining a mixed signal, which is sent to the limiting amplifier. 248. The limiting amplifier 248 performs a limiting amplification process on the mixed electrical signal to generate an amplified electrical signal. Specifically, since the mixed signal waveform generated by the mixer 247 is small, the limiting amplifier 248 is required to amplify the mixed signal. Thereby, a waveform-amplified electric signal is obtained and sent to the second modulator 243. The second modulator 243 performs protocol conversion on the amplified electrical signal to generate a first communication electrical signal, which is sent to the photoelectric converter. The second photoelectric converter 241 converts the first communication electrical signal into a first communication optical signal, thereby converting the transmitted electrical signal into an optical signal and transmitting it to the corresponding second passive optical splitter 25.

After the current wireless signal transceiving node 24 receives the first pulse signal, the synchronization controller 23 is further configured to generate a reception stop command, and send it to the current wireless signal transceiving node 24, and the wireless signal transceiving node 24 stops receiving the first pulse signal. The synchronization controller 23 generates a connection receiving command and transmits it to the connection wireless signal transmitting and receiving node 24 of the current wireless signal transmitting and receiving node 24; the connecting wireless signal transmitting and receiving node 24 starts receiving the first pulse signal simultaneously transmitted by the plurality of wireless communication nodes 13 to generate the first A communication optical signal is transmitted to the corresponding second passive optical splitter 25.

The plurality of second passive optical splitters 25 transmit the received first communication optical signal generated by the corresponding connected wireless signal transceiver node 24 to the second signal optical fiber 26, and the second optical fiber transmits the first communication optical signal to the second optical The communication machine 27 performs optical signal processing.

In the above-mentioned train-to-ground communication process, each wireless communication node 13 of the in-vehicle wireless communication group synchronously emits the same frequency in accordance with the communication protocol specified by the system, and the first pulse signal of the micro-power synchronized in time, these synchronized micro- The first pulse signal of power forms a wireless signal transceiving chain pointing to the terrestrial communication system, thereby being received by a radio signal transceiving node 24 in the radio signal transceiving chain; the radio signal transceiving node 24 is in the synchronizing controller 23 of the radio signal transceiving chain. Under the control of the control, the received signal is converted into a protocol, and converted into an optical signal by the second photoelectric converter 241 of the wireless signal transceiving node 24, and then the light is received according to the instruction of the second optical communication device 27 at the receiving end of the terrestrial network. The signal is transmitted through the fiber to the ground receiving end for processing.

During the train travel, with the movement of the train, the linear wireless communication group will move with the train until the wireless signal transmitting and receiving node BF(k) of the ground chain network is disconnected, but due to the wireless signal transmitting and receiving nodes between the ground network The length of the distance and the line type wireless communication group are equal. Therefore, when the line type wireless communication group is separated from the wireless signal transmitting and receiving node BF(k), it is necessary to simultaneously access another identical and wirelessly working in accordance with the moving direction. a signal transceiving node BF(k-1) or a radio signal transceiving node BF(k+1), and the new radio signal transmitting and receiving node receives the radio communication signal transmitted by the line type wireless communication group, and sequentially receives each radio signal in sequence. The second photoelectric converter 241 of the transceiver node converts into an optical signal for transmission to the second optical communication unit 27 of the terrestrial communication network for processing. For convenience of description, the above BF represents a wireless signal transceiving node, BF(k) represents a kth radio signal transceiving node, BF(k-1) represents a k-1th radio signal transceiving node, and BF(k+1) represents a k+1 wireless signal transceiving nodes.

Therefore, the in-vehicle line type wireless communication group moves with the chain type wireless network formed by the train along the ground wireless signal transmission and reception chain, and each of the wireless communication nodes 13 of the line type wireless communication group sequentially passes the wireless of the ground chain type wireless network. The signal transceiving node 24, since each wireless communication node 13 is fully synchronized, when the train passes, the signals received by the wireless signal transceiving node 24 of the terrestrial network are identical and are not affected by the train moving process.

At the same time, although the in-vehicle line type wireless communication group is also moving at a high speed during the high-speed movement of the train, the radio waves transmitted by the line type wireless communication group are substantially perpendicular to the wireless signal transmitting and receiving nodes of the terrestrial network, and the light is used. The direct modulation of communication, whereby the Doppler effect has little effect on the communication process. Further, since the transmission direction of the radio waves in the line type wireless communication group is perpendicular to the terrestrial wireless signal transmission and reception chain, there is a communication path mainly based on the direct path with high signal to noise ratio, and power adjustment through the wireless communication group. The use of a high-quality antenna system avoids multipath interference and ensures communication quality during fast train travel.

In the case of ground-oriented train communication, the vehicle-to-ground communication mainly includes two parts, one is a wireless signal transceiver chain transmitting signal, and the other is a vehicle-mounted wireless communication group column receiving signal.

When the ground wireless signal receiving and transmitting chain transmits a signal, the synchronization controller 23 generates a synchronous transmission signal and transmits it to all the wireless signal transmitting and receiving nodes 24, and all the wireless signal transmitting and receiving nodes 24 synchronously emit the same frequency according to the communication protocol specified by the system, and synchronize in time. The second pulse signal, whereby each of the wireless signal transceiving nodes 24 of the wireless signal transceiving chain simultaneously simultaneously transmits the same second pulse signal under the control of the synchronizing controller 23.

Specifically, the first signal fiber 21 transmits a second signal optical signal, wherein the first signal fiber 21 transmits an optical signal, and the second signal optical signal refers to a signal that the wireless signal transceiver chain transmits to the wireless communication group. The plurality of first passive optical splitters 22 process the second signal optical signals transmitted by the first signal fiber 21 to obtain multiple identical branched optical signals, and send the same to the corresponding wireless signal transceiver node 24, thereby realizing The signal optical signals are transmitted downward in the form of a broadcast, so the branched optical signals received at each of the wireless signal transmitting and receiving nodes 24 are the same. The second photoelectric converter 241 of each wireless signal transceiver node 24 receives the branch optical signal corresponding to the first passive optical splitter 22, and converts the branched optical signal into a second electrical signal, thereby completing the conversion of the optical signal to the electrical signal. The process is sent to the second modulator 243. The second frequency generator 242 generates a frequency signal that is sent to the second modulator 243. The second modulator 243 receives the synchronous transmission command sent by the synchronization controller 23, modulates the second electrical signal into the frequency signal according to the synchronous transmission instruction, generates a second synchronous driving signal, and transmits the second synchronous driving signal to the second power amplifier 244, where the modulation The modulation mode of the device is pulse modulation, such as OOK or DPIM. The second power amplifier 244 amplifies the second synchronous driving signal to generate an amplified second synchronous driving signal. Specifically, since the waveform of the second synchronous driving signal generated by the second modulator 243 is small, the second power amplifier 244 is required. The second synchronous drive signal is amplified to obtain a waveform-significantly amplified second synchronous drive signal. The second antenna 245 transmits the second pulse signal according to the second synchronous driving signal, and the second antenna 245 is preferably a radio frequency antenna. Specifically, the radio frequency antenna generates the micro power according to the amplified second driving signal generated by the second power amplifier 244. The second pulse signal, the second pulse signal of the micro power, may be a radio frequency signal and sent to the wireless communication group column.

When the wireless communication group is listed as a received signal, the first antenna 135 of the plurality of wireless communication nodes 13 receives the communication signal transmitted by the wireless signal transmitting and receiving node 24 in the wireless signal transmission and reception chain. The first modulator 133 demodulates the second pulse signal to generate a second communication electrical signal; the first photoelectric converter 131 generates a second communication optical signal corresponding to the second communication electrical signal generated by the first demodulator. The signal processor 14 receives the second communication optical signal sent by each of the wireless communication nodes 13, respectively, performs filtering processing on the same communication optical signal generated by the plurality of wireless communication nodes 13, and obtains the received optical signal, and the processed received optical signal is processed. The second optical fiber 15 is transmitted to the first optical communication device 16 for processing of receiving the optical signal.

Further, in this example, taking the communication frequency of 90 Gm wave as an example, if the calculation is performed at a signal modulation rate of 5%, a communication rate of about 4.5 G can be obtained at a carrier frequency of 90 G. Similarly, a frequency of 45 G is relatively easy to obtain. The communication rate that can be obtained in these frequency bands of 60G is also very considerable, far exceeding the communication speed that the current communication system can provide for high-speed trains. Therefore, it is possible to arrange multiple frequency points for communication in the millimeter wave frequency band. Communication bandwidth.

In the above communication process, although the high-speed mobile transmitter is moving at high speed, the radio wave transmitted by the linear wireless communication group is substantially perpendicular to the wireless signal transmitting and receiving node 24 of the terrestrial network, and is adopted. The direct modulation of optical communication, the Doppler effect has little effect on the communication process.

In the structure of the above communication system, the wireless communication group and the wireless signal transceiving node of the terrestrial communication network can be regarded as being in one plane, and the node having the maximum Doppler effect appearing in the terrestrial network is corresponding to the in-vehicle line type wireless. When there are any two wireless communication nodes in the communication group column, there is a simplified Doppler effect formula:

Where: Δf = frequency offset value caused by the Doppler effect;

F = operating frequency, in this case 90G;

V = moving speed, in this case 360km / h, 0.1km / s;

C = speed of light, 300,000km / s;

θ=the angle between the moving direction of the in-vehicle wireless communication group and the ground wireless signal transceiving chain;

When the distance between the wireless communication nodes of the in-vehicle line type wireless communication group is d, and the vertical distance between the wireless communication group column and the wireless signal transmitting and receiving node of the ground chain type wireless signal transmission and reception chain is also d, the moving speed is For 360km/h, the above formula can be written as:

Substituting c=300,000km/s and F=90G can obtain the frequency offset value Δf=13416Hz caused by the maximum Doppler effect.

This frequency offset rate is less than 15 parts per million. For the fundamental frequency of 90G, it will not affect the normal operation of the wireless transceiver when working under direct modulation conditions.

In summary, in the above-mentioned vehicle-to-ground communication process, the in-vehicle wireless communication group continuously moves along the ground wireless signal transmission and reception chain, sequentially passes through each wireless signal transmitting and receiving node of the terrestrial communication network, and sequentially sends the wireless signal transmitting and receiving nodes to the ground end in sequence. The wireless communication signal, each wireless signal transceiver node of the terrestrial communication network receives the communication signals in sequence according to the communication rules of the network, and is sent by the optical communication network to the core network on the ground for processing. At the same time, each wireless signal transceiving node of the terrestrial communication network transmits a communication signal to the in-vehicle wireless communication group, and is received when the in-vehicle wireless communication group passes, and then transmitted by the in-vehicle optical communication network to the in-vehicle core network for data processing, thereby The continuous communication process of the high-speed moving train to the ground network in a section is realized.

In addition, it should be noted that during the train operation, each in-vehicle wireless communication node listed in the in-vehicle wireless communication group can also receive the signal transmitted by the terrestrial wireless signal receiving and transmitting chain while transmitting the signal, and can use frequency division multiplexing. achieve.

Similarly, each wireless signal receiving node in the terrestrial wireless signal receiving and receiving chain uses a frequency division multiplexing technology to transmit signals to the wireless communication group column while receiving signals transmitted by the in-vehicle wireless communication group. That is to say, the wireless communication node and the wireless signal receiving node can simultaneously receive and transmit signals, thereby implementing a continuous communication process during train motion.

A person skilled in the art should further appreciate that the elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both, in order to clearly illustrate hardware and software. Interchangeability, the composition and steps of the various examples have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods for implementing the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present invention.

The steps of a method or algorithm described in connection with the embodiments disclosed herein can be implemented in hardware, a software module executed by a processor, or a combination of both. The software module can be placed in random access memory (RAM), memory, read only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or technical field. Any other form of storage medium known.

The specific embodiments of the present invention have been described in detail with reference to the preferred embodiments of the present invention. All modifications, equivalent substitutions, improvements, etc., made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

A wireless communication system, characterized in that the wireless communication system comprises: a wireless communication group column and a wireless signal transceiving chain;

The wireless communication group column includes: a first group of column fibers, an optical splitter, and a plurality of wireless communication nodes;

The first set of column fibers for transmitting a first signal light signal;

The optical splitter is configured to perform split processing on the first signal optical signal to obtain multiple identical split optical signals;

The plurality of wireless communication nodes are configured to synchronously generate the same first pulse signal according to the split optical signal, whereby each wireless communication node of the wireless communication group simultaneously simultaneously transmits the first pulse signal;

The wireless signal transceiving chain includes: a synchronization controller, a first signal fiber, a plurality of first passive optical splitters, a plurality of wireless signal transceiving nodes, a plurality of second passive optical splitters, and a second signal optical fiber;

The synchronization controller is configured to generate a receiving control command, and send, by using the first signal fiber and the first passive optical splitter, a plurality of wireless signals corresponding to the first passive optical splitter and requiring receiving a pulse signal a current wireless signal transceiving node in the transceiver node;

The current wireless signal transceiving node is configured to receive a first pulse signal that is simultaneously sent by a plurality of wireless communication nodes of the wireless communication group, and generate a first communication optical signal according to the first pulse signal;

The second passive optical splitter is configured to receive a first communication optical signal sent by a corresponding wireless signal transceiver node, and send the signal to the second signal fiber.
The wireless communication system according to claim 1, wherein after the current wireless signal transceiving node receives the first pulse signal, the synchronization controller is further configured to generate a reception stop instruction, and send the The current wireless signal transceiving node stops receiving the first pulse signal.
The wireless communication system according to claim 2, wherein the synchronization controller is further configured to generate a connection receiving command, and send the connection to the connection wireless signal transceiving node of the current wireless signal transceiving node;

The connecting wireless signal transceiving node starts receiving a first pulse signal simultaneously sent by the plurality of wireless communication nodes, and generates a first communication optical signal;

The second passive optical splitter is configured to receive a first communication optical signal that is sent by the connection wireless signal transceiver node and send the signal to the second signal fiber.
The wireless communication system according to claim 3, wherein the wireless signal transceiving chain further comprises:

The second optical communication device is connected to the second signal fiber for processing the first communication optical signal sent by the second signal fiber.
The wireless communication system according to claim 1, wherein the wireless communication node comprises: a first photoelectric converter, a first frequency generator, a first modulator, a first power amplifier, and a first antenna;

The first photoelectric converter is configured to receive a split optical signal sent by the optical splitter, convert the split optical signal into a first electrical signal, and send the signal to the first modulator;

The first frequency generator is configured to generate a frequency signal and send the signal to the first modulator;

The first modulator is configured to generate a first synchronous driving signal according to modulating the first electrical signal into the frequency signal, and send the first synchronous driving signal to the first power amplifier;

The first power amplifier is configured to amplify the first synchronous driving signal to generate an amplified first synchronous driving signal;

The first antenna is configured to send a first pulse signal according to the amplified first synchronous driving signal.
The wireless communication system according to claim 5, wherein said wireless signal transceiving node comprises: a second antenna, a low noise amplifier, a mixer, a second frequency generator, a limiting amplifier, a second modulator, and Second photoelectric converter;

The second antenna is configured to receive a first pulse signal that is sent by multiple wireless communication nodes of the wireless communication group;

The low noise amplifier is configured to perform low noise amplification processing on the first pulse signal received by the second antenna, generate a processing pulse signal, and send the signal to the mixer;

The second frequency generator is configured to generate a frequency signal and send the signal to the mixer;

The mixer is configured to process the frequency signal into a mixed electrical signal according to the processing pulse signal;

The limiting amplifier is configured to perform a limiting amplification process on the mixed electrical signal to generate an amplified electrical signal;

The second modulator is configured to perform protocol conversion on the amplified electrical signal to generate a first communication electrical signal;

The second photoelectric converter is configured to convert the first communication electrical signal into a first communication optical signal.
The wireless communication system according to claim 6, wherein said wireless signal transceiving node further comprises a second power amplifier;

The first signal fiber is further configured to transmit a second signal optical signal;

The plurality of first passive optical splitters are respectively configured to process the second signal optical signal transmitted by the first signal fiber to obtain a branched optical signal;

The second photoelectric converter is further configured to receive the branch optical signal corresponding to the first passive optical splitter, convert the branched optical signal into a second electrical signal, and send the second optical signal to the second modulator;

The second frequency generator is further configured to generate a frequency signal and send the signal to the second modulator;

The second modulator is further configured to receive a synchronous transmission command sent by the synchronization controller, and modulate the second electrical signal into the frequency signal according to the synchronous transmission instruction to generate a second synchronous driving signal, And sent to the second power amplifier;

The second power amplifier is further configured to amplify the second synchronous driving signal to generate an amplified second synchronous driving signal;

The second antenna is further configured to send a second pulse signal according to the second synchronous driving signal, so that each wireless signal transceiving node of the wireless signal transceiving chain simultaneously transmits the same synchronously under the control of the synchronous controller The second pulse signal.
The wireless communication system according to claim 7, wherein said wireless communication group column comprises a signal processor respectively connected to said plurality of wireless communication nodes;

Each of the plurality of wireless communication nodes is further configured to receive a second pulse signal sent by the wireless signal transceiving node;

The first modulator is further configured to demodulate the second pulse signal to generate a second communication electrical signal;

The first photoelectric converter is further configured to generate a second communication optical signal corresponding to the second communication electrical signal generated by the first demodulator;

The signal processor is configured to respectively receive a second communication optical signal sent by each of the wireless communication nodes, and perform filtering processing to receive the optical signal.
The wireless communication system according to claim 8, wherein the wireless communication group further comprises:

A second set of column fibers coupled to the signal processor for transmitting a received optical signal transmitted by the signal processor.
The wireless communication system according to claim 9, wherein the wireless communication group further comprises:

a first optical communication device coupled to the second set of column fibers for processing received optical signals transmitted by the second set of columns of fibers.