Communication System

Abstract

The present invention relates to a communication system for communicating between a vehicle and a fixed base station, wherein the vehicle travels along a predetermined motion trajectory, and the communication is performed using a slot waveguide extending parallel to the motion trajectory of the vehicle, wherein at least one antenna connected to a transmitting and receiving device of the fixed base station and at least one antenna of the vehicle extend into the slot waveguide, wherein when the vehicle moves, the antenna of the vehicle moves along the longitudinal direction of the slot waveguide, and at least two independent transmitting and receiving devices for at least one channel are respectively arranged on the fixed base station and the vehicle, or at least one transmitting and receiving device for at least two channels, each having two antenna connections, is arranged, and the transmitting and receiving devices are respectively connected to at least one common antenna via at least one coupler, and signals of all channels are respectively transmitted and received via the common antenna.

Description

Technical Field

[0001] The invention relates to a communication system according to the preamble of claim 1. Background Art

[0002] Such a communication system is known, for example, from DE 10 2013 002 227 B4. It enables communication between a vehicle traveling along a predetermined motion trajectory and a stationary base station with high bandwidth and high interference immunity. The antenna is accordingly arranged on the vehicle so that the antenna extends through the slot into the cavity of the slot waveguide and can receive and / or transmit electromagnetic waves propagating along the waveguide when the vehicle is traveling. The corresponding antenna of the stationary base station is arranged at one end of the slot waveguide.

[0003] In a communication system of this type, high data rates are required, in particular because it is intended to control the movement of one or more vehicles relative to a stationary base station, and this control can be safety-critical in some cases. For example, it must be ensured that a control command to stop in front of an obstacle reaches the vehicle reliably within a predetermined time period so that a collision with the obstacle can be avoided. High data rates can be achieved by using system components with a correspondingly large bandwidth, but commercially available components of this type carry corresponding costs. Summary of the invention

[0004] It is therefore the object of the present invention to provide an advantageous and inexpensive possibility for achieving high data rates for a communication system of the type mentioned above.

[0005] This object is achieved according to the invention by a communication system having the features of claim 1. Advantageous embodiments are given in the respective dependent claims.

[0006] According to the present invention, for a communication system for communicating between a vehicle traveling along a predetermined motion trajectory and a fixed base station using a slot waveguide extending parallel to the vehicle's motion trajectory, at least one antenna connected to the transmitting and receiving device of the fixed base station and at least one antenna of the vehicle extend into the slot waveguide, wherein when the vehicle moves, the antenna of the vehicle moves along the longitudinal direction of the slot waveguide, and at least two independent transmitting and receiving devices for at least one channel are respectively arranged on the fixed base station and the vehicle, and the transmitting and receiving devices are respectively connected to at least one common antenna via at least one coupler, and signals of all channels are respectively transmitted and received via the common antenna.

[0007] Therefore, an increase in the data rate is achieved by providing at least two different channels, for which the slot waveguide is used as a common transmission medium. At least one additional channel is provided by using an additional transceiver. In order to be able to transmit and receive with only one antenna, the signals of the different channels are brought together on the path to the antenna by means of at least one coupler, or are provided to the transceiver simultaneously in the opposite transmission direction by means of the coupler.

[0008] This not only enables correspondingly higher data rates, but also simplifies the exchange of messages of different categories compared to the use of single-channel transceivers with higher bandwidth. For example, messages can be easily assigned to different channels according to content and / or priority and transmitted by different transceivers, thereby simplifying message processing both on the transmitter side and on the receiver side. In addition, it is possible for different system components on the stationary base station side and on the vehicle side to communicate with each other simultaneously but independently of each other via different transceivers.

[0009] The use of multiple transceivers also enables partial redundancy of the hardware, so that even if one of the transceivers fails, communication can be maintained. These transceivers, which are active system components, have a higher failure rate than passive system components. This partial redundancy of the hardware can also be used for redundant data transmission, that is, the same message can be transmitted simultaneously by means of different transceivers on different channels to improve the reliability of data transmission. In this case, it is not necessary to increase the data rate for reliability.

[0010] Advantageously, the coupler is a reciprocal three-port coupler, which couples the first connection and the second connection to the third connection, respectively. If the signal path leads to different transceivers from the first connection and the second connection, if the first connection and the second connection of the coupler are not coupled to each other, the different transceivers can transmit and receive independently of each other. That is, one transceiver can be in the transmission mode, and the other can be in the reception mode. If the attenuation between these connections of the coupler is too low, interference with the receiving operation will be caused. The suitable embodiment of this coupler is the Wilkinson coupler. The feature of this coupler is that the loss between the mutually coupled connections is low, while the attenuation between the mutually uncoupled connections is high, and can be realized in a simple manner.

[0011] For longer transmission paths, the following solution is advantageous for achieving a sufficient communication range: the slot waveguide comprises two sections that are independent of each other, the two sections extending in opposite directions from a position where their ends are arranged adjacent to each other, and each section of the slot waveguide is provided with its own antenna of the base station that extends into the corresponding section and is fixed in position. The maximum total length of the transmission path can thereby be significantly increased.

[0012] The antenna of the preferably fixed-position base station is arranged at the adjacent ends of the individual sections, which are advantageously located in the center of the transmission path. With this arrangement, the maximum total length can be increased to twice the maximum length of each individual section. The maximum length of the individual sections is limited by the attenuation of the signal when propagating in the slot waveguide.

[0013] If the slot waveguide consists of two separate sections and two antennas are used at a stationary base station, it is advantageous that two couplers in the form of reciprocal three-port couplers are connected in series so that the first connection and the second connection of the first coupler are each connected to one of the transceiver devices, the first connection and the second connection of the second coupler are each connected to one of the antennas, and the third connections of the two couplers are connected to each other. Compared to an arrangement with only one antenna, an expansion to a dual antenna system is possible by only requiring a further coupler of the same type as already present in the variant with only one antenna, in addition to the second antenna as a further system component.

[0014] Advantageously in this configuration, the first coupler makes its first connection and the second connection be coupled to its third connection, and its first connection and the second connection are not coupled to each other, and the second coupler makes all three connections be coupled to each other. That is, the first coupler is connected to two different transceivers, and these two transceivers should not interfere with each other when running simultaneously, and the second coupler is connected to two antennas in different sections of the slot waveguide, and in order to transmit messages, these two antennas should not be separated from each other, but should form a continuous transmission medium. Therefore, it is not desirable to not couple between two of the three connections of the second coupler. The suitable implementation of the second coupler is a tap or a reactive power divider / reactance power divider, which are reciprocal three-port couplers, and they couple all three connections of them to each other, as desired by existing applications, wherein the insertion loss between different connection pairs is different and need not be the same.

[0015] If the slot waveguide includes two independent sections, it is advantageous that two antennas are arranged successively at a predetermined distance along the driving direction on the vehicle, the vehicle has two transceiver devices for at least two different channels, two couplers in the form of reciprocal three-port couplers are connected in parallel between the two antennas and the two transceiver devices, the two couplers couple the first connection part and the second connection part to the third connection part respectively, the first connection part and the second connection part are not coupled to each other, so that the first connection part of each coupler is connected to the first transceiver device respectively, the second connection part of each coupler is connected to the second transceiver device respectively, and the third connection part of each coupler is connected to one of the antennas respectively. Therefore, each transceiver device of the vehicle can transmit and receive independently of each other via any antenna of the vehicle.

[0016] If the slot waveguide comprises two sections separated from each other by a gap, the distance between the antennas on the vehicle is preferably greater than the gap width to such an extent that at least one of the antennas in one of the two sections of the slot waveguide is always ready for transmission and reception. This makes it possible to avoid interruptions in communication when passing through the gap between the two sections of the slot waveguide.

[0017] Optionally, an attenuation link is connected between the transceiver of the fixed base station and the connection of the transceiver of the coupler assigned to the base station and / or between the transceiver of the vehicle and the connection of the transceiver of the coupler assigned to the vehicle, so as to reduce the power transmitted by the antenna to a desired value under a given power of the transmitter or reduce the power received by the antenna to a desired value before feeding into the receiver. In addition, the attenuation link can also be used to reduce the unwanted residual power between the following connections of the coupler: these connections of the coupler should not actually be coupled to each other.

[0018] A preferred solution for separating the different channels is to assign them to different frequency bands. The different channels can also each consist of at least two mutually bundled channels of a multi-channel transceiver. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The following describes an embodiment of the present invention according to the accompanying drawings.

[0020] Figure 1 shows a schematic cross-sectional view of a slot waveguide with an antenna extending therein,

[0021] Figure 2 Show according to Figure 1 together with a block diagram of other components of a first embodiment of a communication system according to the present invention,

[0022] Figure 3 Show according to Figure 1 A schematic longitudinal cross-sectional view of a slot waveguide together with a block diagram of other components of a second embodiment of a communication system according to the present invention

[0023] Figure 4 A block diagram shows components of a stationary base station according to a third specific embodiment of a communication system according to the present invention. DETAILED DESCRIPTION

[0024] Figure 1 A schematic cross-sectional view of a slot waveguide 1 is shown, which shows how the slot waveguide is used in the prior art in a communication system for communicating between a vehicle 4 traveling along a predetermined motion trajectory and a stationary base station 5 and / or between a plurality of such vehicles. The antenna 3 of the vehicle extends through the slot 2 into the slot waveguide 1 to transmit and receive electromagnetic waves propagating along the slot waveguide 1. When the vehicle moves along its predetermined motion trajectory, the antenna 3 moves together with the vehicle in the longitudinal direction of the slot waveguide 1. In particular, the vehicle 4 can be guided along a set route by a track.

[0025] like Figure 2 As shown, the antenna 6 of the fixed base station 5 also extends into the slot waveguide 1. The antenna is connected to two transmitting and receiving devices 10 and 11, which are referred to as transceivers 10 and 11 below, via a coupler 7 and optional attenuation links 8 and 9. The antenna 6 of the fixed base station 5 can also extend into the slot waveguide 1 through the slot 2 like the antenna 3 of the vehicle 4, but this is not necessary since it does not have to move. The transceivers 10 and 11 are connected to a control device 12 of the fixed base station 5, which controls the entire transport system and / or monitors its operation, for example based on video signals and status reports, and the transport system can also include multiple vehicles 4. The control device 8 can perform control functions, but it is not necessary, and can also be used specifically for monitoring operation. For this purpose, continuous two-way data communication is carried out between the control device 8 of the fixed base station 5 and the control device 13 of the vehicle 4 via the slot waveguide 1 as a transmission path.

[0026] like Figure 2 As further shown, the antenna 3 of the vehicle 4 is also connected via a coupler 14 and optional attenuation elements 15 and 16 to two transceiver devices 17 and 18, referred to below as transceivers 17 and 18. The transceivers 17 and 18 are connected to a control device 13 of the vehicle 4, which controls the movement and other functions of the vehicle 4. The components of the onboard part of the communication system according to the invention and their circuit topology thus correspond to the parts arranged in the stationary base station 5.

[0027] However, it is not necessary to arrange only a single control device 12 or 13 as a corresponding message source or receiver at the fixed-position base station 5 or on the vehicle 4, respectively, but both the transceivers 10 and 11 of the fixed-position base station 5 and the transceivers 17 and 18 of the vehicle 4 can be connected to two independent message sources or receivers, respectively, which should be able to communicate simultaneously but independently of each other. The invention easily realizes simultaneous and independent communication between at least two pairs of message sources and receivers via a single slot waveguide. In particular, in this configuration, messages can also be transmitted in opposite directions at the same time, for example, one message is transmitted from the transceiver 10 of the fixed-position base station 5 to the transceiver 17 of the vehicle 4, and at the same time another message is transmitted from the transceiver 18 of the vehicle 4 to the transceiver 11 of the fixed-position base station 5.

[0028] The transceivers 10 and 11 of the stationary base station 5 operate on different channels, i.e., different frequency bands of the frequency band for which the slot waveguide 1 is suitable as a transmission path. The same is true for the transceivers 17 and 18 of the vehicle, wherein the transceivers 10 and 17 and the transceivers 11 and 18 respectively operate on the same channel. Compared with using only a single transceiver each, the simultaneous use of two transceivers operating on different channels on the stationary base station 5 and the vehicle 4 doubles the maximum transmittable data rate.

[0029] In order to require only a single antenna 6, 3 for transmitting and receiving signals in both the stationary base station 5 and the vehicle 4, couplers 7, 14 are provided respectively. The coupler 7 of the stationary base station has three connections. The antenna 6 of the stationary base station 5 is connected to one of them. The transceivers 10 and 11 are each connected to one of the other two connections, wherein the attenuation link 8 or 9 can be connected between the coupler 7 and the transceivers 10 and 11. The coupler 7 is directionally selective, i.e., it symmetrically couples each connection to which the transceivers 10 and 11 are connected to the connection to which the antenna 6 is connected, and makes the two connections to which the transceivers 10 and 11 are connected uncoupled from each other. Therefore, the coupler acts as a splitter of the received signal, i.e., it distributes the signal power received by the antenna approximately evenly to the two transceivers 10 and 11, and acts as a combiner of the transmitted signals from the transceivers 10 and 11, i.e., it provides them together to the single antenna 6. The function of the coupler 14 of the vehicle 4 is the same with respect to its antenna 3 and its transceivers 17 and 18.

[0030] A suitable design of the coupler 7 or 14 is the design of a Wilkinson power divider, which essentially comprises: two lines each of a quarter of the intermediate frequency wavelength of the frequency band to be transmitted between the antenna connection and each of the other two connections, and an absorbing impedance between the other two connections. A coupler 7 or 14 of this structural type can be economically realized using circuit boards or hybrid technology.

[0031] The control device 12 of the stationary base station 5 is connected to the two transceivers 10 and 11 there, and the control device 13 of the vehicle 4 is connected to the two transceivers 17 and 18 there. The control devices 12 and 13 therefore have two channels available for their communication and thus a significantly larger bandwidth available overall. This not only allows higher data rates to be achieved compared to the use of a single transceiver with a higher bandwidth, but also simplifies the exchange of messages of different categories. For example, messages can be assigned to two different channels depending on the content and / or priority of the message, thereby simplifying the processing of the message. When different categories of data are assigned in this way on different channels, the bandwidth of the channel can be different as required. For example, video signals can be transmitted on a channel with a bandwidth of 40 MHz, and control data can be transmitted on a channel with a bandwidth of 20 MHz.

[0032] In addition, partial redundancy of the hardware is provided by two transceivers 10 and 11 or 17 and 18, respectively, and in an emergency, two respectively assigned attenuation links 8 and 9 or 15 and 16. If a transceiver and / or an attenuation link fails, the entire communication can be handled via the corresponding still operational part of the communication system, thereby avoiding the overall failure of the communication system and thus improving reliability. This is particularly important for transceivers 10 and 11 or 17 and 18, because they have a higher failure rate as active components than passive components (such as antennas 3 and 6, couplers 7 and 14 and attenuation links 8, 9, 15 and 16). However, it is also possible to transmit a single message via transceivers 10 and 11 or 17 and 18 at the same time to improve the reliability of transmission.

[0033] As described above, at the fixed base station 5 and the vehicle 4, there can be two independent units instead of only one control device 12 or 13, which are respectively connected to one of the transceivers 10 and 11 or 17 and 18 and serve as sources or receivers of messages sent or received by the transceivers 10 and 11 or 17 and 18.

[0034] Figure 3A second embodiment of the communication system according to the present invention is shown. This embodiment is provided for a transport system of a relatively large length, in which, in order to achieve a sufficient effective communication range, a fixed-position base station 105 is not arranged at the end, but is offset toward the center of the transport path, or is arranged directly in the center of the transport path, and the slot waveguides 101A, 101B include at least two different sections 101A and 101B, which are separated from each other by a gap 119, which is an expansion joint for (accommodating) thermodynamic length changes. Two independent antennas 106A and 106B are provided, which are respectively assigned to one of the different sections 101A or 101B of the slot waveguide 101A and are connected to a common control device 112 of the fixed-position base station 105. For this purpose, two couplers 107 and 120 are provided, wherein the design of the coupler 107 is the same as the coupler 7 of the first embodiment. The two first connections of the first coupler 107 are likewise connected to the transceivers 110 and 111 via optional attenuation elements 108 and 109 , like the corresponding connections of the coupler 7 with the transceivers 10 and 11 of the first embodiment.

[0035] The second coupler 120 may have a different design, since the non-coupling of two of its three connections differs from the requirements for the coupler 107. On the contrary, it may even be desirable for the second coupler 120 to have as low an attenuation as possible between all three of its connections, so that the two antennas 106A and 106B are coupled not only to the first coupler 107 but also to each other, so that a signal transmitted by a vehicle 104 in one of the two sections 101A or 101B of the slot waveguide 101 for another vehicle 104 can be received, the other vehicle being located in a respectively different section 101B or 101A, so as to thereby avoid collisions between transmission signals from different vehicles 104. A suitable coupler type for this is a tap.

[0036] However, the third connection portion of the coupler 107 is not connected to a single antenna, but is connected to the third connection portion of the second coupler 120. The antennas 106A and 106B are connected to the two first connection portions of the second coupler 120. These antennas are not coupled to each other through the second coupler 120, and are coupled to the third connection portions, respectively. Through this circuit, the signals received by the two antennas 106A and 106B are first combined by the second coupler 120, and then the first coupler 107 provides the combined signal to the two transceivers 110 and 111 with uniform power distribution. In the opposite direction, the transmission signals sent by the two transceivers 110 and 111 are first combined by the first coupler 107, and then the second coupler 120 provides the combined signal to the two antennas 106A and 106B for transmission with uniform power distribution.

[0037] In this way, the transmission signals of the two transceivers 110 and 111 are uniformly transmitted to the two sections 101A and 101B of the slot waveguides 101A and 101B, and the signals received by the antennas 106A and 106B from the two sections 101A and 101B of the slot waveguides 101A and 101B are provided to the two transceivers 110 and 111. The gap 119 between the sections 101A and 101B of the slot waveguides 101A and 101B is preferably located in the center of the travel path of the transportation system, and the antennas 106A and 106B are arranged near the gap 119, thereby doubling the maximum effective range of communication compared to the arrangement of a single antenna at the end of a single slot waveguide.

[0038] The two antennas 103A and 103B of the vehicle 104 are offset from each other in the direction of travel thereof, so that at the gap 119 between the two sections 101A and 101B of the slot waveguide 101A, 101B, the antenna 103A extends into one section 101A of the slot waveguide 101A, 101B, and the other antenna 103B extends into the other section 101B. This prevents communication interruptions when the vehicle 104 passes through the gap 119 between two different sections 101A and 101B of the slot waveguide 101A, 101B, in particular when the antenna 101A or 101B is located in the region of the gap 119 and therefore can no longer transmit signals via the antenna 101A or 101B.

[0039] Two transceivers 117 and 118 are provided on the vehicle 104, which operate on the same channel as the transceivers 110 and 111 of the fixed base station, so that the transceivers 117 and 118 of the vehicle 104 are respectively assigned to the corresponding transceivers 110 and 111 of the fixed base station. The two corresponding connections of the transceivers 117 and 118 are respectively used for the signal paths leading to the corresponding antennas. There is a signal path from the first of these connections to the first antenna 103A, and there is a signal path from the second of these connections to the second antenna 103B, so that the transceivers 117 and 118 are connected to the antennas 103A and 103B in a one-to-one correspondence.

[0040] In order to realize the above configuration, the antennas 103A and 103B are respectively connected to the third connection parts of the couplers 114A and 114B, which have the same design as the coupler 107 of the fixed-position base station 105. The first connection part of each of these couplers 114A and 114B is respectively connected to the connection part of the first transceiver 117 via an optional attenuation link 115A or 115B. The second connection part of each of these couplers 114A and 114B is respectively connected to the connection part of the second transceiver 118 via an optional attenuation link 116A or 116B. The couplers 114A and 114B each couple their first connection part and second connection part to their third connection part, and respectively make their first connection part and second connection part uncoupled from each other. Therefore, a continuous signal path exists at all times between each transceiver 110 and 111 of the fixed base station 105 and the transceiver 117 or 118 of the vehicle 104 assigned to it, in particular even when the vehicle 104 drives through the gap 119 between the slot waveguide sections 101A and 101B and one of the two antennas 103A or 103B of the vehicle 104 is located in the area of ​​the gap 119.

[0041] according to Figure 2 The communication effective range of the circuit device of the first embodiment of the fixed base station 5 may also be sufficient, the circuit device having only a single antenna 6 and a single coupler 7, but requiring a slot waveguide 101A, 101B comprising two independent sections 101A and 101B and a gap 119 used as an expansion joint to compensate for thermodynamic length changes. In this case, the antennas are arranged at the gap 119 at the ends of the different sections 101A or 101B of the slot waveguide 101A, 101B facing each other, and the antennas are connected by flexible conductor sections. Signals are transmitted between the different sections 101A or 101B of the slot waveguides 101A, 101B using this arrangement of passive elements. However, if uninterrupted communication is to be ensured when passing through the gap 119, due to the presence of the gap 119, in this case, two antennas 103A and 103B arranged successively in the longitudinal direction are also required on the vehicle 104, as well as according to Figure 3 A second embodiment of the present invention is a vehicle-side portion of a communication system.

[0042] Figure 4 A block diagram showing a portion of a third embodiment of a communication system according to the present invention arranged in or on a fixed-position base station 205. Figure 2The difference from the first embodiment is that the two transceivers 210 and 211 connected to the control device 212 of the fixed base station 205 each have two independent antenna connections, which are assigned to different channels. Such a two-channel transceiver 210 or 211 with two antenna connections is known. Each of the two antenna connections is first connected to an optional attenuation link 208 or 209 via a first coupler 221 or 222 and then to a first input or a second input of a coupler 207, the design of which is the same as the coupler 7 of the first embodiment. The antenna 206 is connected to the third connection of the coupler 207. According to Figure 4 The configuration can be used not only on one side of the fixed-position base station, but also on one side of the vehicle in a mirrored manner, i.e., it can replace Figure 1 Vehicle side configuration shown.

[0043] The two antenna connections of the transceivers 210 and 211 are coupled by couplers 221 and 222 so that the two channels of each single transceiver 210 and 211 are bundled into one channel with twice the bandwidth, thereby doubling the data rate of a single channel. Such channel bundling itself is known and is not the subject of the present invention. This embodiment is only shown schematically, and the coupling of different transmitting and receiving devices according to the present invention with a common slot waveguide antenna can also be applied to the already bundled channels of such a transmitting and receiving device. Similar to Figure 1 The first embodiment can also be used on the vehicle side according to Figure 4 Configuration.

[0044] according to Figure 4 The configuration can also be applied to the embodiment with two antennas. Figure 3 In the second embodiment of the present invention, the part of the communication system consisting of the control device 112, the transceivers 110 and 111, the attenuation links 108 and 109 and the coupler 107 is composed of Figure 4 The configuration of excluding the antenna 206. In this case, instead of the antenna 206, the coupler 120 is connected to the coupler 207, and the antennas 106A and 106B are connected to the other two connection parts thereof.

[0045] In this case, two transceivers with four antenna connections are required on the vehicle side, which are connected to the two antennas of the vehicle via a total of four couplers corresponding to couplers 221 and 222, four optional attenuation links and two couplers corresponding to coupler 207, wherein the connection between the antenna-side coupler and the optional attenuation link or the optional transceiver-side attenuation link is similar to Figure 3 The vehicle-side configuration is partially crossed to provide a signal path between each of the two antennas and the corresponding two antenna connections of each transceiver.

[0046] In the above-described embodiments, two single-channel transceivers or two dual-channel transceivers each having a channel bundle are provided. This should not be understood as limiting the present invention to two channels. On the contrary, the present invention also includes configurations with more than two channels. For example, a three-channel system can be realized by using three transceivers in a fixed-position base station and a vehicle, respectively, in combination with a coupler in the form of a reciprocal four-port coupler, which couples one port to the other three ports, respectively, and makes the other three ports mutually uncoupled. A Wilkinson coupler with four connecting parts is particularly suitable for this. For a communication system with four channels, four transceivers can be provided in a fixed-position base station and a vehicle, respectively, and three couplers with three connecting parts, respectively, as they appear in the embodiments described here, can be cascaded together in two stages so as to divide the signal at one input terminal into four outputs, or, in the opposite direction, to combine the signals from the four input terminals into one output.

Claims

1. A communication system for communicating between a vehicle (4; 104) and a fixed-position base station (5; 105; 205), the vehicle moving along a predetermined motion trajectory, the communication system using a slot waveguide (1; 101) extending parallel to the predetermined motion trajectory of the vehicle (4; 104), at least one antenna (6; 106A, 106B; 206) connected to a transceiver (10, 11; 110, 111; 210, 211) of the fixed-position base station (5; 105; 205), and at least one antenna (3; 103A; 203B) of the vehicle (4; 104). 103B) extends into the slot waveguide, wherein when the vehicle (4; 104) moves, at least one antenna (3; 103A; 103B) moves along the longitudinal direction of the slot waveguide (1; 101), The invention is characterized in that at least two independent transceivers are arranged on the fixed-position base station, each transceiver has at least one channel, and the frequency band of the channel is different from the channel of another transceiver. At least two independent transceivers are arranged on the vehicle, each transceiver has at least one channel, the frequency band of the channel is different from the channel of another transceiver, At least two independent transceivers on the fixed-position base station are connected to at least one common antenna via at least one coupler of the fixed-position base station, at least two independent transceivers on the vehicle are connected to at least one common antenna on the vehicle via at least one coupler on the vehicle, and, Signals of all channels are transmitted and received via at least one common antenna on the stationary base station and at least one common antenna on the vehicle.

2. The communication system according to claim 1, characterized in that The coupler (7, 14; 107, 120, 114A, 114B; 207; 307A, 307B) is a reciprocal three-port coupler that couples the first connection part and the second connection part to the third connection part, respectively.

3. The communication system according to claim 2, characterized in that The coupler decouples the first connection portion and the second connection portion from each other.

4. The communication system according to claim 3, characterized in that: The coupler is a Wilkinson coupler.

5. The communication system according to claim 1, characterized in that: The slot waveguide includes two sections (101A, 101B) independent of each other, which extend in opposite directions from positions where their ends are arranged adjacent to each other, and each section of the slot waveguide is provided with its own fixed base station antenna extending into the corresponding section.

6. The communication system according to claim 5, characterized in that: The antenna of the stationary base station is arranged in the two sections (101A, 101B) close to a position where the ends of the two sections are adjacent to each other.

7. The communication system according to claim 5 or 6, characterized in that: The fixed-position base station has two independent transceivers (110, 111), and two couplers (107, 120) in the form of reciprocal three-port couplers are connected in series between these transceivers and the two antennas (106A, 106B) of the fixed-position base station, so that the first connection part and the second connection part of the first coupler (107) are respectively connected to one of the two independent transceivers (110, 111), the first connection part and the second connection part of the second coupler (120) are respectively connected to one of the two antennas (106A, 106B), and the third connection parts of the two couplers (107, 120) are connected to each other.

8. The communication system according to claim 7, characterized in that: The first connection part and the second connection part of the first coupler (107) are coupled to the third connection part, the first connection part and the second connection part of the first coupler are not coupled to each other, and all three connection parts of the second coupler (120) are coupled to each other.

9. The communication system according to claim 8, characterized in that: The second coupler (120) is a tap or a reactive power splitter.

10. The communication system according to claim 1, characterized in that: Two antennas (103A, 103B) are arranged successively at a predetermined distance along the driving direction on the vehicle. The vehicle has two transceivers (117, 118) respectively used for at least two different channels. Two couplers (114A, 114B) in the form of reciprocal three-port couplers are connected in parallel between the two antennas (103A, 103B) and the two transceivers (117, 118). The two couplers couple the first connection part and the second connection part to the third connection part respectively, and the first connection part and the second connection part are not coupled to each other, so that the first connection part of each coupler is respectively connected to the first transceiver (117), the second connection part of each coupler is respectively connected to the second transceiver (118), and the third connection part of each coupler is respectively connected to one of the two antennas (103A, 103B).

11. The communication system according to claim 10, characterized in that: The slot waveguide comprises two sections (101A, 101B) separated from each other by a gap (119), and the distance between two antennas (103A, 103B) on the vehicle is greater than the width of the gap (119) to such an extent that at least one of the two antennas (103A, 103B) is always in a position ready for transmission and reception in one of the two sections (101A, 101B) of the slot waveguide.

12. The communication system according to claim 1, characterized in that: Attenuation links (8, 9, 15, 16; 108, 109, 115A, 115B, 116A, 116B; 208, 209) are respectively connected between the transceiver (10, 11; 110, 111; 210, 211) of a fixed base station (5; 105; 205) and the connection part of the coupler (7; 107; 207) assigned to the transceiver of the base station and / or between the transceiver (17, 18; 117, 118) of a vehicle (4; 104) and the connection part of the coupler (14; 114A, 114B) assigned to the transceiver of the vehicle.

13. The communication system according to claim 1, characterized in that: The different channels respectively include at least two channels of the multi-channel transceiver that are bundled with each other.

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