CN116017365B

CN116017365B - Self-adaptive wireless link simulcasting method and system

Info

Publication number: CN116017365B
Application number: CN202310186890.9A
Authority: CN
Inventors: 欧阳建生; 周卫; 胡锐
Original assignee: Guangdong Yuexin Microsystem Research Institute
Current assignee: Guangdong Yuexin Microsystem Research Institute
Priority date: 2023-03-02
Filing date: 2023-03-02
Publication date: 2023-06-09
Anticipated expiration: 2043-03-02
Also published as: CN116017365A

Abstract

The invention relates to a self-adaptive wireless link simulcasting method and a system, belongs to the technical field of communication, and solves the problems that an ad hoc network is not flexible enough and a session effect is not ideal in a scene with complex and changeable field environment. The method comprises the following steps: when JD1, JD2, ZH0 to JDN are located in an unobstructed straight line or an unobstructed road segment, U1 is set between JD1 and JD2, U2 is set between ZH0 and JD2 and UN is set between JDN-1 and JDN; dynamically allocating the link time slots of the adaptive wireless link simulcast system, and detecting the reallocation of the auxiliary link time slots through the same-frequency interference when the same-frequency interference is brought by the time slot collision; initiating a packet session request through a specific user communication terminal in U1 to UN, and entering a packet session procedure after receiving a packet session request reply; and transmitting the synchronous signals to other user communication terminals from U1 to UN through the specific user communication terminal in the packet session process. The high dynamic environment requirements are met by adopting time slot conflict detection and dynamic allocation of link time slots.

Description

Self-adaptive wireless link simulcasting method and system

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method and system for simulcasting a self-adaptive wireless link.

Background

In earthquake relief and emergency sites, a wireless ad hoc network system with survivability and independent of wired links is the best choice, and a wireless ad hoc network simulcast system is one of the best choices.

Common wireless ad hoc network simulcast systems are divided into two types, namely a centerless and a centerless, usually master-slave mode, and a centerless, usually fixed connection mode. The master-slave mode with the center is suitable for use scenes without wired link erection conditions and with just good erection positions of the master base station, such as a communication system in a forest area, and is not suitable for flexible and mobile earthquake relief, emergency and safety guarantee field use. The centerless fixed connection mode is the most common in the private network communication industry at present, and can be applied to the scenes of earthquake relief, emergency, safety guarantee and the like.

The wireless ad hoc network simulcast system applied to earthquake relief, emergency and safety guarantee sites at present is carefully deployed and planned, and can meet the use requirement of a simple site, but has insufficient flexibility and mobility, and has limitations when encountering complex and changeable site environments. For example, the emergency communication vehicle with large-scale activity site and special route safety guarantee has high mobility, the position of the base station in the wireless communication network may change, the base station at the beginning of the session establishment receives the transmitting signal of the user communication terminal in the session process, and the phenomenon of discontinuous session and even session interruption can occur. For example, the air drop portable base station in the earthquake relief scene has randomness, the position of the base station in the wireless communication network is uncertain, and the self-networking cannot be realized in a master-slave mode and a fixed connection mode.

The method aims at improving two problems existing in the prior art in application scenes with high dynamic performance and complex and changeable field environments: the networking communication is performed by human intervention, and the ad hoc network is not flexible enough; the session effect is not ideal, and the phenomenon of session discontinuity and even session interruption can occur.

Disclosure of Invention

In view of the above analysis, the present invention aims to provide a method and a system for simulcasting an adaptive wireless link, so as to solve the problems of insufficient flexibility and unsatisfactory session effect of ad hoc network, discontinuous session and even session interruption in an application scenario with high dynamic property and complex and changeable field environment.

In one aspect, an embodiment of the present invention provides a method for simulcasting an adaptive radio link, including: when a first motor vehicle base station JD1, a second motor vehicle base station JD2, a command vehicle base station ZH0 to an Nth motor vehicle base station JDN are positioned on an unobstructed straight road section or an unobstructed turning road section, a first user communication terminal U1 is arranged between the first motor vehicle base station JD1 and the second motor vehicle base station JD2, a second user communication terminal U2 is arranged between the command vehicle base station ZH0 and the second motor vehicle base station JD2, and an Nth user communication terminal is arranged between an N-1 motor vehicle base station JDN-1 and the Nth motor vehicle base station JDN, wherein N is a positive integer greater than 2; dynamically allocating the link time slots of the self-adaptive wireless link simulcast system, wherein when the same-frequency interference is brought by the time slot conflict, the auxiliary link time slots are reallocated through the same-frequency interference detection; initiating a packet session request through a specific user communication terminal among the first to nth user communication terminals U1 to UN, and entering a packet session procedure after receiving a packet session request reply; and in the packet session process, transmitting a synchronous signal to other user communication terminals from the first user communication terminal U1 to the Nth user communication terminal UN through the specific user communication terminal.

The beneficial effects of the technical scheme are as follows: the link time slot conflict detection is adopted to dynamically allocate the link time slot, so that the self-adaptive wireless link simulcast base station can meet the use requirement of a high dynamic environment.

Based on a further improvement of the above method, when the first to nth motor vehicle base stations JD1 to ZH0 are located on the unobstructed straight line section, dynamically allocating the link time slots of the adaptive wireless link simulcast system includes: when the command vehicle base station ZH0 is started first, detecting that downlink time slots 1, 3, 5, … and 2N-1 are idle time slots, and selecting 1 as a link downlink time slot of the command vehicle base station ZH 0; when the Nth motor communication vehicle base station JDN is started, detecting that the downlink time slot 1 is occupied and the downlink time slots 3, 5, … and 2N-1 are idle time slots, and selecting 3 as a link downlink time slot of the Nth motor communication vehicle base station JDN; since the second mobile communication vehicle base station JD2 can receive the link signal of the mobile communication vehicle JD3, it is detected that the downlink time slots 1 and 3 are occupied and the downlink time slots 5, …, 2N-1 are idle time slots, and 5 is selected as the link downlink time slot of the second mobile communication vehicle base station JD 2; and when the first motor vehicle base station JD1 can receive the link signals of the second motor vehicle base station JD2 and the command vehicle base station ZH0, but cannot receive the link signals of the nth motor vehicle JDN, detecting that downlink timeslots 1 and 5 are occupied and downlink timeslots 3 and 2N-1 are idle timeslots, and selecting 3 as the downlink timeslot of the first motor vehicle base station JD 1.

Based on a further improvement of the above method, when the first vehicle base station JD1, the second vehicle base station JD2, the command vehicle base station ZH0 to the nth vehicle base station JDN travel to the unobstructed road section, the linear distance between the first vehicle base station JD1 and the nth vehicle base station JDN decreases, the first vehicle base station JD1 and the nth vehicle base station JDN can receive each other's wireless link signals and the allocated wireless link time slots are the same, so that co-channel interference is generated between the first vehicle base station JD1 and the nth vehicle base station JDN.

Based on a further improvement of the above method, the generating co-channel interference between the first vehicle base station JD1 and the nth vehicle base station JDN further includes: when the second motor communication vehicle base station JD2 and the command vehicle base station ZH0 detect signal data on the link time slot 3 in 3 continuous time slot periods, but check of the detected signal data fails, respectively notifying a conflict time slot number 3 and a base station number of which the currently selected time slot 3 is a downlink time slot in the own downlink time slot; and when the first motor vehicle base station JD1 and the N motor vehicle base station JDN respectively receive signal data frames with conflicting time slot numbers in time slots 1 and 5, reselecting a downlink time slot of the N motor vehicle base station JDN with larger number according to the base station numbers in the signal data frames.

Based on a further improvement of the above method, when the specific user communication terminal is the second user communication terminal U2, initiating a packet session request by a specific user communication terminal of the first to nth user communication terminals U1 to UN further comprises: transmitting a packet session request through the second user communication terminal U2 and retransmitting 3 times; simultaneously receiving a packet session request of the second user communication terminal U2 through a first adjacent base station, starting a timer and forwarding the packet session request in a downlink time slot of the first adjacent base station, wherein the first adjacent base station is the command vehicle base station ZH0 and the second motor vehicle base station JD2 which are adjacent to the second user communication terminal U2; receiving, by the first mobile communication vehicle base station JD1 and the nth mobile communication vehicle base station JDN, a packet session request of the first neighboring base station in link timeslots DS1 and DS5, and forwarding the packet session request in a downlink timeslot DS3 of the first mobile communication vehicle base station JD1 and a downlink timeslot DS3 of the nth mobile communication vehicle base station JDN or a reselected link downlink timeslot, respectively, wherein when the timer T1 expires, the base station of the first neighboring base station that receives the second user communication terminal U2 with better signal quality sends a packet session request acknowledgement to the second user communication terminal U2, and retransmits 3 times.

The beneficial effects of the technical scheme are as follows: and by adopting an optimized forwarding rule, only the signal data frame with the optimal signal quality is forwarded, so that the user communication terminal is ensured to achieve the optimal receiving effect, and session discontinuity or interruption caused by the high dynamic property of an application scene is avoided.

Based on a further improvement of the above method, when the timer T1 expires, the base station of the first neighboring base station that receives the signal quality of the second user communication terminal U2 better, transmitting a packet session request reply to the second user communication terminal U2 includes: receiving a packet session request of a second user communication terminal U2 forwarded by the command vehicle base station ZH0 through the second motor communication vehicle base station JD2 in a link time slot DS1 and extracting signal quality information of the packet session request forwarded by the command vehicle base station ZH 0; receiving a packet session request of a second user communication terminal U2 forwarded by the second motor communication vehicle base station JD2 in a link time slot DS5 through the command vehicle base station ZH0 and extracting signal quality information of the packet session request forwarded by the second motor communication vehicle base station JD 2; when the timer is overtime, the command vehicle base station ZH0 and the second motor vehicle base station JD2 respectively compare the signal quality of the packet session request of the second user communication terminal U2 directly received with the signal quality of the packet session request forwarded by the second motor vehicle base station JD2 or the command vehicle base station ZH0 previously extracted; and determining the base station with better signal quality in the packet session request directly received by the command vehicle base station ZH0 and the second motor communication vehicle base station JD2 according to the comparison result, and sending a packet session request response to the second user communication terminal U2.

Based on a further improvement of the above method, the transmitting of the synchronization signal to the other user communication terminals of the first to nth user communication terminals U1 to UN through the specific user communication terminal during the packet session comprises: transmitting packet session signal data through the specific user communication terminal, wherein the packet session signal data comprises a plurality of signal data frames, and the signal data frames comprise a signal data frame number SDN, a source base station number BSN and a wireless access forwarding time slot number TSN, and the specific user communication terminal comprises a first user communication terminal U1 or a second user communication terminal U2; receiving packet session signal data from the second user communication terminal U2 or the first user communication terminal U1 through the first neighboring base station or a second neighboring base station simultaneously, and forwarding packet session information data in own downlink timeslots DS1 and DS5 or DS3 and DS5, respectively, wherein the second neighboring base station is the first motor vehicle base station JD1 and the second motor vehicle base station JD2 neighboring the first user communication terminal U1; and receiving packet session signal data of one or two base stations of the first adjacent base station or the second adjacent base station through the first motor communication vehicle base stations JD1 to N motor communication vehicle base stations JDN and the command vehicle base station ZH0, and then forwarding the packet session signal data received by the wireless link channel and the wireless access channel through the first motor communication vehicle base stations JD1 to N motor communication vehicle base stations JDN and the command vehicle base station ZH0 in a wireless access channel when the wireless access forwarding time slot number TSN is reached.

Based on a further improvement of the above method, the signal data frame number SDN is generated by the second user communication terminal U2 or the first user communication terminal U1; generating, by the first neighboring base station or the second neighboring base station, the source base station number BSN and the radio access forwarding time slot number TSN, where the first neighboring base station or the second neighboring base station generates, based on a current radio access time slot number WASN and a base station parameter time slot offset SO, a radio access forwarding time slot number TSN according to a signal data frame received from the second user communication terminal U2 or the first user communication terminal U1, where the radio access forwarding time slot number tsn=current radio access time slot number wasn+base station parameter time slot offset SO.

In another aspect, an embodiment of the present invention provides an adaptive wireless link simulcast system, including: the plurality of base stations comprise a first motor communication vehicle base station JD1, a second motor communication vehicle base station JD2 and command vehicle base stations ZH0 to Nth motor communication vehicle base stations JDN which are positioned on an unobstructed straight road section or an unobstructed turning road section in sequence; a plurality of user communication terminals comprising: a first user communication terminal U1 located between the first motor vehicle base station JD1 and the second motor vehicle base station JD2, a second user communication terminal U2 located between the command vehicle base station ZH0 and the second motor vehicle base station JD2, and an nth user communication terminal located between an nth-1 motor vehicle base station JDN-1 and the nth motor vehicle base station JDN, wherein N is a positive integer greater than 2; the time slot allocation module is used for dynamically allocating the link time slots of the self-adaptive wireless link simulcast system, wherein when the same-frequency interference is brought by the time slot conflict, the auxiliary link time slots are reallocated through the same-frequency interference detection; a packet session request and response module for initiating a packet session request through a specific user communication terminal among the first to nth user communication terminals U1 to UN and entering a packet session procedure after receiving a packet session request response; and a packet session module, configured to perform, during the packet session, transmission of a synchronization signal to other user communication terminals from the first user communication terminal U1 to the nth user communication terminal UN through the specific user communication terminal.

Based on a further improvement of the above system, when the first to nth motor vehicle base stations JD1 to JDN and the command vehicle base station ZH0 are located on the unobstructed straight road section, the time slot allocation module is configured to: when the command vehicle base station ZH0 is started first, detecting that downlink time slots 1, 3, 5, … and 2N-1 are idle time slots, and selecting 1 as a link downlink time slot of the command vehicle base station ZH 0; when the Nth motor communication vehicle base station JDN is started, detecting that the downlink time slot 1 is occupied and the downlink time slots 3, 5, … and 2N-1 are idle time slots, and selecting 3 as a link downlink time slot of the Nth motor communication vehicle base station JDN; since the second mobile communication vehicle base station JD2 can receive the link signal of the mobile communication vehicle JD3, it is detected that the downlink time slots 1 and 3 are occupied and the downlink time slots 5, …, 2N-1 are idle time slots, and 5 is selected as the link downlink time slot of the second mobile communication vehicle base station JD 2; and when the first motor vehicle base station JD1 can receive the link signals of the second motor vehicle base station JD2 and the command vehicle base station ZH0, but cannot receive the link signals of the nth motor vehicle JDN, detecting that downlink timeslots 1 and 5 are occupied and downlink timeslots 3 and 2N-1 are idle timeslots, and selecting 3 as the downlink timeslot of the first motor vehicle base station JD 1.

Compared with the prior art, the invention has at least one of the following beneficial effects:

1. the embodiment of the invention adopts the link time slot conflict detection to dynamically allocate the link time slots, so that the self-adaptive wireless link simulcast base station can meet the use requirement of a high dynamic environment; adopting an optimized forwarding rule to forward only signal data frames with optimal signal quality, ensuring that a user communication terminal achieves an optimal receiving effect, and avoiding discontinuous or interrupted conversation caused by high dynamic property of an application scene;

2. the problem that the prior art needs human intervention to carry out the ad hoc network can be solved through the dynamic allocation of the link time slots; the problems that the session effect is not ideal in the high dynamic environment, the session is discontinuous and even the session is interrupted can be solved through the optimized forwarding rule of the link channel and the access channel;

3. the self-adaptive wireless link simulcast base station and the system can be used for scenes such as earthquake relief, emergency maintenance and stability, safety guarantee and the like.

In the invention, the technical schemes can be mutually combined to realize more preferable combination schemes. Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and drawings.

Drawings

The drawings are only for purposes of illustrating particular embodiments and are not to be construed as limiting the invention, like reference numerals being used to designate like parts throughout the drawings;

fig. 1 is a flow chart of an adaptive wireless link simulcasting method according to an embodiment of the present invention;

fig. 2 is a schematic diagram of the components of an adaptive wireless link simulcast system according to an embodiment of the present invention;

fig. 3 is a schematic diagram of the composition of a user communication terminal according to an embodiment of the present invention;

FIG. 4 is a schematic diagram illustrating components of a scheduling management center according to an embodiment of the present invention

Fig. 5 is a schematic diagram of a single radio access channel base station composition according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a four radio access channel base station configuration according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a link slot allocation for a straight road segment according to an embodiment of the present invention;

fig. 8 is a simulcast signaling diagram of a straight road segment U2 initiating a packet session according to an embodiment of the present invention;

fig. 9 is a simulcast signaling diagram of U2 through U1 and U3 during a straight-line segment packet session in accordance with an embodiment of the present invention;

fig. 10 is a simulcast signaling diagram of U1 through U2 and U3 during a straight-line segment packet session according to an embodiment of the present invention;

Fig. 11 is a schematic diagram of a link slot allocation with collision for a curve segment in accordance with an embodiment of the present invention;

fig. 12 is a schematic diagram of a collision-free link slot allocation for a curve segment in accordance with an embodiment of the present invention;

fig. 13 is a simulcast signaling diagram of a curve U2 initiating a packet session in accordance with an embodiment of the present invention;

fig. 14 is a simulcast signaling diagram of U2 through U1 and U3 during a turn section packet session in accordance with an embodiment of the present invention;

fig. 15 is a simulcast signaling diagram of U1 through U2 and U3 during a turn section packet session in accordance with an embodiment of the present invention; and

fig. 16 is a block diagram of an adaptive wireless link simulcast system in accordance with an embodiment of the present invention.

Detailed Description

Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form a part hereof, and together with the description serve to explain the principles of the invention, and are not intended to limit the scope of the invention.

Referring to fig. 1, in one embodiment of the present invention, an adaptive wireless link simulcasting method is disclosed, comprising: in step S102, when the first motor vehicle base station JD1, the second motor vehicle base station JD2, and the command vehicle base stations ZH0 to N-th motor vehicle base stations JDN are located on an unobstructed straight road section or an unobstructed turning road section, the first user communication terminal U1 is disposed between the first motor vehicle base station JD1 and the second motor vehicle base station JD2, the second user communication terminal U2 is disposed between the command vehicle base station ZH0 and the second motor vehicle base station JD2, and the N-th user communication terminal is disposed between the N-1-th motor vehicle base station JDN-1 and the N-th motor vehicle base station JDN, wherein N is a positive integer greater than 2; in step S104, dynamically allocating a link time slot of the adaptive wireless link simulcast system, wherein when the co-channel interference is brought by a time slot conflict, the re-allocation of the auxiliary link time slot is detected by the co-channel interference; in step S106, a packet session request is initiated by a specific user communication terminal among the first to nth user communication terminals U1 to UN, and a packet session procedure is entered after receiving a packet session request reply; and in step S108, during the packet session, transmitting a synchronization signal to the other user communication terminals among the first to nth user communication terminals U1 to UN through the specific user communication terminal.

Compared with the prior art, in the adaptive wireless link simulcasting method provided by the embodiment, link time slot conflict detection is adopted to dynamically allocate the link time slots, so that the adaptive wireless link simulcasting base station can meet the use requirement of a high dynamic environment.

Hereinafter, each step of the adaptive radio link simulcasting method according to an embodiment of the present invention will be described in detail with reference to fig. 1.

In step S102, when the first motor vehicle base station JD1, the second motor vehicle base station JD2, the command vehicle base station ZH0 to the nth motor vehicle base station JDN are located on an unobstructed straight road section (also referred to as an unobstructed road section) or an unobstructed turning road section (also referred to as an unobstructed road section), the first user communication terminal U1 is disposed between the first motor vehicle base station JD1 and the second motor vehicle base station JD2, the second user communication terminal U2 is disposed between the command vehicle base station ZH0 and the second motor vehicle base station JD2, and the nth user communication terminal is disposed between the N-1 th motor vehicle base station JDN-1 and the nth motor vehicle base station JDN, where N is a positive integer greater than 2.

In step S104, the link time slots of the adaptive wireless link simulcast system are dynamically allocated, wherein when the co-channel interference is brought by the time slot collision, the secondary link time slots are reallocated through co-channel interference detection. When the first vehicle base station JD1 does not receive the link signal of the nth vehicle base station JDN, and the minimum value of the detected idle time slots is allocated to the downlink time slot of the first vehicle base station JD1, so that the downlink time slots of the first vehicle base station JD1 and the nth vehicle base station JDN are the same.

When the first to nth motor communication vehicle base stations JD1 to ZH0 are located on the unobstructed straight road section, dynamically allocating the link time slots of the adaptive wireless link simulcast system includes: when the command vehicle base station ZH0 is started first, detecting that downlink time slots 1, 3, 5, … and 2N-1 are idle time slots, and selecting 1 as a link downlink time slot of the command vehicle base station ZH 0; when the Nth motor vehicle base station JDN is started, detecting that the downlink time slot 1 is occupied and the downlink time slots 3, 5, … and 2N-1 are idle time slots, and selecting 3 as a link downlink time slot of the Nth motor vehicle base station JDN; since the second mobile communication vehicle base station JD2 can receive the link signal of the mobile communication vehicle JD3, it is detected that the downlink time slots 1 and 3 are occupied and the downlink time slots 5, …, 2N-1 are idle time slots, and 5 is selected as the link downlink time slot of the second mobile communication vehicle base station JD 2; … and when the first vehicle base station JD1 is able to receive the link signals of the second vehicle base station JD2 and the command vehicle base station ZH0, but the link signal of the nth vehicle JDN is not received, it is detected that the downlink timeslots 1 and 5 are occupied and that the downlink timeslots 3 and 2N-1 are idle timeslots, and 3 is selected as the link downlink timeslot of the first vehicle base station JD 1.

When the first motor vehicle base station JD1, the second motor vehicle base station JD2, and the command vehicle base stations ZH0 to N motor vehicle base station JDN travel to a non-blocking turning road section, the linear distance between the first motor vehicle base station JD1 and the N motor vehicle base station JDN is reduced, the first motor vehicle base station JD1 and the N motor vehicle base station JDN can receive wireless link signals of each other and the allocated wireless link time slots are the same, so that co-channel interference is generated between the first motor vehicle base station JD1 and the N motor vehicle base station JDN.

Specifically, the co-channel interference generated between the first vehicle base station JD1 and the nth vehicle base station JDN further includes: when the second motor vehicle base station JD2 and the command vehicle base station ZH0 detect signal data on the link time slot 3 in 3 consecutive time slot periods, but fail to verify the detected signal data, respectively notifying a conflict time slot number 3 and a base station number of which the currently selected time slot 3 is a downlink time slot in the own downlink time slot, namely, the first motor vehicle base station JD1 and the nth motor vehicle base station JDN; and when the first and nth vehicle base stations JD1 and JDN receive the signal data frames of conflicting slot numbers at slots 1 and 5, respectively, reselecting a link downlink slot 2N-1 (e.g., slot 7) for the larger numbered nth vehicle base station JDN according to the base station number in the signal data frame.

In step S106, a packet session request is initiated by a specific user communication terminal among the first to nth user communication terminals U1 to UN, and a packet session procedure is entered after receiving a packet session request reply.

When the specific user communication terminal is the second user communication terminal U2, initiating a packet session request through the specific user communication terminal among the first to nth user communication terminals U1 to UN further includes: transmitting a packet session request through the second user communication terminal U2 and retransmitting 3 times; simultaneously receiving a packet session request of a second user communication terminal U2 through a first adjacent base station, starting a timer and forwarding the packet session request in a downlink time slot of the first adjacent base station, wherein the first adjacent base station is a command vehicle base station ZH0 and a second motor communication vehicle base station JD2 which are adjacent to the second user communication terminal U2; the packet session request of the first neighboring base station is received at the link time slots DS1 and DS5 by the first motor vehicle base station JD1 and the nth motor vehicle base station JDN, and forwarded at the downlink time slot DS3 of the first motor vehicle base station JD1 and the downlink time slot DS3 of the nth motor vehicle base station JDN or the reselected link downlink time slot 2N-1 (for example, time slot 7), respectively, wherein when the timer T1 expires, the one of the first neighboring base stations that receives the second user communication terminal U2 with better signal quality transmits a packet session request response to the second user communication terminal U2, and retransmits 3 times.

Specifically, when the timer T1 expires, the base station of the first neighboring base station that receives the signal quality of the second user communication terminal U2 better, transmitting a packet session request response to the second user communication terminal U2 includes: receiving a packet session request of a second user communication terminal U2 forwarded by the command vehicle base station ZH0 through a second motor communication vehicle base station JD2 in a link time slot DS1 and extracting signal quality information of the packet session request forwarded by the command vehicle base station ZH 0; receiving a packet session request of a second user communication terminal U2 forwarded by a second motor communication vehicle base station JD2 in a link time slot DS5 through a command vehicle base station ZH0 and extracting signal quality information of the packet session request forwarded by the second motor communication vehicle base station JD 2; when the timer expires, the command vehicle base station ZH0 and the second motor vehicle base station JD2 respectively compare the signal quality information of the directly received second user communication terminal U2 with the signal quality information of the previously extracted packet session request forwarded by the second motor vehicle base station JD2 or the command vehicle base station ZH0, for example, the command vehicle base station ZH0 compares the signal quality of the directly received second user communication terminal U2 with the signal quality of the previously extracted packet session request forwarded by the second motor vehicle base station JD2, and the second motor vehicle base station JD2 compares the signal quality of the directly received packet session request of the second user communication terminal U2 with the signal quality of the previously extracted packet session request forwarded by the command vehicle base station ZH 0; and determining the base station with better signal quality in the packet session request directly received by the command vehicle base station ZH0 and the second motor communication vehicle base station JD2 according to the comparison result, and sending a packet session request response to the second user communication terminal U2.

In step S108, during the packet session, synchronization signal transmission is performed to other user communication terminals among the first to nth user communication terminals U1 to UN through the specific user communication terminal.

During the packet session, the transmission of the synchronization signal to the other user communication terminals among the first to nth user communication terminals U1 to UN through the specific user communication terminal includes: transmitting packet session signal data through a specific user communication terminal, wherein the packet session signal data comprises a plurality of signal data frames, the signal data frames comprise a signal data frame number SDN, a source base station number BSN and a wireless access forwarding time slot number TSN, and the specific user communication terminal comprises a first user communication terminal U1 or a second user communication terminal U2; receiving packet session signal data from a second user communication terminal U2 or a first user communication terminal U1 through a first neighboring base station or a second neighboring base station, and forwarding packet session information data in own downlink timeslots DS1 and DS5 or DS3 and DS5, respectively, wherein the second neighboring base station is a first motor vehicle base station JD1 and a second motor vehicle base station JD2 neighboring the first user communication terminal U1; the first to nth motor vehicle base stations JDN 1 to ZH0 receive packet session signal data of one or both of the first or second neighboring base stations, and then forward the packet session signal data received by the wireless link channel and the wireless access channel in the wireless access channel when the wireless access forwarding slot number TSN is received.

Specifically, the signal data frame number SDN is generated by the second user communication terminal U2 or the first user communication terminal U1; generating a source base station number BSN and a radio access forwarding time slot number TSN by a first or second neighboring base station, wherein the first or second neighboring base station generates the radio access forwarding time slot number TSN based on a current radio access time slot number WASN and a base station parameter time slot offset SO according to a signal data frame received from the second or first user communication terminal U2 or U1, wherein the radio access forwarding time slot number tsn=the current radio access time slot number wasn+the base station parameter time slot offset SO.

Referring to fig. 16, another embodiment of the present invention discloses an adaptive wireless link simulcast system comprising: a plurality of base stations 1602, a plurality of user communication terminals 1604, a time slot allocation module 1606, a packet session request and response module 1608, and a packet session module 1610.

The plurality of base stations 1602 includes a first motor vehicle base station JD1, a second motor vehicle base station JD2, a command vehicle base station ZH0 through an nth motor vehicle base station JDN, which are located in order on an unobstructed straight road segment or an unobstructed cornering road segment; the plurality of user communication terminals 1604 include: a first user communication terminal U1 located between the first motor vehicle base station JD1 and the second motor vehicle base station JD2, a second user communication terminal U2 located between the command vehicle base station ZH0 and the second motor vehicle base station JD2, and an nth user communication terminal located between the nth-1 motor vehicle base station JDN-1 and the nth motor vehicle base station JDN, wherein N is a positive integer greater than 2; the timeslot allocation module 1606 is configured to dynamically allocate a link timeslot of the adaptive wireless link simulcast system, where when co-channel interference is caused by a time slot collision, the co-channel interference is used to detect that the auxiliary link timeslot is reallocated; the packet session request and response module 1608 is configured to initiate a packet session request through a specific user communication terminal among the first to nth user communication terminals U1 to UN and enter a packet session procedure after receiving a packet session request response; and a packet session module 1610 is configured to perform, during a packet session, transmission of a synchronization signal to other user communication terminals from the first user communication terminal U1 to the nth user communication terminal UN through a specific user communication terminal.

When the first to nth motor communication vehicle base stations JD1 to ZH0 are located on the unobstructed straight road section, the time slot allocation module is configured to: when the command vehicle base station ZH0 is started first, detecting that downlink time slots 1, 3, 5, … and 2N-1 are idle time slots, and selecting 1 as a link downlink time slot of the command vehicle base station ZH 0; when the Nth motor vehicle base station JDN is started, detecting that the downlink time slot 1 is occupied and the downlink time slots 3, 5, … and 2N-1 are idle time slots, and selecting 3 as a link downlink time slot of the Nth motor vehicle base station JDN; since the second mobile communication vehicle base station JD2 can receive the link signal of the mobile communication vehicle JD3, it is detected that the downlink time slots 1 and 3 are occupied and the downlink time slots 5, …, 2N-1 are idle time slots, and 5 is selected as the link downlink time slot of the second mobile communication vehicle base station JD 2; and when the first motor vehicle base station JD1 can receive the link signals of the second motor vehicle base station JD2 and the command vehicle base station ZH0, but cannot receive the link signals of the nth motor vehicle JDN, detecting that the downlink timeslots 1 and 5 are occupied and that the downlink timeslots 3 and 2N-1 are idle timeslots, and selecting 3 as the downlink timeslot of the first motor vehicle base station JD 1.

Hereinafter, an adaptive wireless link simulcast system and method according to an embodiment of the present invention will be described in detail, by way of specific example, with reference to fig. 2 to 15.

The self-adaptive wireless link simulcast base station and the system comprise the following contents:

content 1: adaptive radio link simulcast system composition

The adaptive wireless link simulcast system is composed of more than 2 simulcast base stations, more than 2 user communication terminals and a scheduling management center, as shown in fig. 2.

The simulcast base station is mainly responsible for signal access and forwarding of the user communication terminal; the user communication terminal is mainly responsible for man-machine interaction, access request and the like; the dispatching management center is generally arranged in the emergency command control center and is mainly responsible for command dispatching and monitoring management, and the dispatching management center can also be provided with a recording function and a positioning function.

The user communication terminal is composed of a transmitting module, a receiving module, a control module, a man-machine interface (comprising a liquid crystal screen, a microphone, a loudspeaker and keys), a battery, an antenna and the like, as shown in fig. 3. The transmitting module is responsible for transmitting wireless access signals; the receiving module is responsible for receiving the wireless access signal; the control module is responsible for controlling the receiving module, the transmitting module and the man-machine interface; the man-machine interface is responsible for signal acquisition, display and the like; the battery is responsible for supplying power to the transmitting module, the receiving module, the control module and the man-machine interface; the antenna is responsible for transforming a guided wave propagating on a transmission line into an electromagnetic wave propagating in an unbounded medium (usually free space) or vice versa.

The dispatch management center is composed of a computer terminal, a microphone, a server, a network switch, a vehicle-mounted station or fixed station, management software, dispatch software and other service software, as shown in fig. 4. The computer terminal is responsible for running a scheduling management software client; the microphone is responsible for voice collection; the server is responsible for running a scheduling management software server; the network switch is responsible for connecting a server of the dispatching management center and a computer terminal; the vehicle-mounted station or the fixed station is responsible for receiving and transmitting wireless access signals; the dispatching management center software comprises, but is not limited to, network management software, dispatching software, network management service software, dispatching service software and recording service software.

Content 2: co-broadcast base station

The simulcast base station adopts a modularized design and a hot-pluggable design, and consists of a base station controller, a power supply, a wireless link subsystem, a wireless access subsystem and a cabinet assembly, wherein the wireless access subsystem comprises two types of multi-channel and single-channel as shown in fig. 5 and 6. And the wireless link transceiver is connected with the base station controller through the motherboard backboard. The motherboard interface 0 and the motherboard interface 1 are connected with a base station controller and comprise a data interface, a synchronous interface and a power interface; the motherboard interface 2 is connected with the wireless link transceiver and comprises a data interface, a synchronous interface, a power interface and a radio frequency interface, the motherboard interfaces 3-6 are connected with the wireless access transceiver and comprise the data interface, the synchronous interface, the power interface and the radio frequency interface, and the motherboard interface 7 is connected with a power supply and comprises a direct current output interface and an alternating current input interface; the duplexer, the combiner and the branching unit are connected to the radio frequency interface of the motherboard backboard through cables; the wireless link antenna and the wireless access antenna can select a vehicle-mounted antenna or a fixed frame antenna and the like according to the installation environment of the simulcast base station.

The base station controller is designed for backup, and can work one by one or can work singly without backup. The base station controller is responsible for completing network layer and application layer functions, including routing of wireless access signals, management of session states and configuration management of the base station. The routing of the wireless access signal refers to a process that the base station forwards and controls the wireless access signal to an uplink or a downlink after receiving the wireless access signal through the wireless access transceiver; the session state is divided into four states of session establishment, session maintenance and session ending, wherein the management of the session state refers to the function that a base station needs to control the session state of each session when a user terminal performs the session; configuration management of a base station means that parameters of the base station can be configured, and the configurable base station parameters include, but are not limited to, operating frequencies and transmit powers of a radio access transceiver and a radio link transceiver, the number of radio link timeslots, timeslot offsets, session maintenance times, and the like.

The power supply is responsible for supplying power to the base station controller, the radio link subsystem, and the radio access subsystem, and the power supply voltage includes the high voltage of the transmitting part and the low voltage of the receiving part.

The radio link subsystem comprises 1 link transceiver, 1 duplexer, 1 antenna and feeder line, as shown in fig. 5. The link transceiver is composed of a receiving path, a transmitting path and a control part. Wherein the link transceiver is responsible for performing data link layer, MAC layer and physical layer functions, wherein the physical layer functions include slot synchronization control of the link signals. The duplexer is responsible for isolating the transmitted and received wireless link signals and ensuring that both the receiving and transmitting can work normally at the same time. The antenna is responsible for transforming a guided wave propagating on a transmission line into an electromagnetic wave propagating in an unbounded medium (usually free space) or vice versa. The feeder is responsible for connecting the link transceiver and the diplexer and the antenna.

The radio access subsystem comprises 1 to 4 radio access transceivers, 1 antenna, feeder line and 1 duplexer (only one radio access transceiver) or 1 4 splitter+1 4 combiner (with multiple radio access transceivers), as shown in fig. 6. The wireless access transceiver is composed of a receiving path, a transmitting path and a control part, wherein the wireless access transceiver is responsible for completing the functions of a data link layer, a MAC layer and a physical layer, and the physical layer functions comprise synchronous control of wireless access signals, including time slot synchronization and phase synchronization. The duplexer is responsible for isolating the transmitted and received wireless access signals and ensuring that both the receiving and transmitting can work normally at the same time. The splitter is used for a receiving end and is responsible for splitting a plurality of received frequency band wireless access signals into a single frequency band and outputting the single frequency band to different wireless access transceivers. The combiner is used for the transmitting end and is responsible for combining multiple radio frequency signals sent from different wireless access transceivers into one path to be sent to the transmitting antenna or the duplexer in front of the antenna, and meanwhile, the mutual influence among the signals of all ports can be avoided. The antenna is responsible for transforming a guided wave propagating on a transmission line into an electromagnetic wave propagating in an unbounded medium (usually free space) or vice versa. The feeder is responsible for connecting the radio access transceiver and the diplexer or the radio access transceiver and the splitter/combiner and the diplexer, the diplexer and the antenna.

The cabinet assembly consists of a cabinet, a motherboard backboard, a wiring groove, a grounding end and the like. The motherboard back plane is responsible for the physical interface connection between the base station controller, the radio link transceiver and the radio access transceiver.

Content 3: dynamic link time slot allocation method

The self-adaptive allocation of the wireless link time slot is the basis of the wireless self-networking, and the flexible self-networking function can be realized only if the time slot allocation has self-adaptability. The fixed connection mode of the fixed slot allocation cannot meet the complex and changeable application scenarios.

The invention discloses a self-adaptive wireless link simulcast base station and a system, wherein the wireless link adopts 8 time slots, and the dynamic allocation principle is as follows:

1. the time slots are numbered 1,2,3,4,5,6,7,8, the odd time slots are downlink time slots, and the even time slots are uplink time slots.

2. After the random simulcast base station is started, the occupation condition of downlink time slots 1,3,5 and 7 is scanned in real time, the scanning time is at least 3 time slot periods, namely the duration of 24 time slots, so that at least 3 opportunities of each time slot are scanned, and the accuracy of a scanning result is ensured.

3. When the base station does not select the downlink time slot, the base station selects according to the scanning result of the downlink time slot: if the idle downlink time slot exists, selecting an idle downlink time slot with the smallest number as the downlink time slot of the wireless link of the base station, and then broadcasting and notifying the time slot; if there is no idle downlink time slot, the simulcast base station cannot be used as an intermediate base station to forward the wireless link signals of other base stations, and the uplink time slot random access principle needs to be applied to the uplink time slot corresponding to 1 or 2 downlink time slots with better occupied signal quality by the simulcast base station.

4. When the base station selects the downlink time slot, determining whether to discard the selection according to the scanning result of the downlink time slot: if the selected time slot is occupied, comparing the ID sizes of the occupied simulcast base station and the own simulcast base station, wherein the occupied ID is small, discarding the selected downlink time slot with the ID being large, and restarting the selected flow.

Content 4: optimized simulcast signal transmission method

The simulcast base stations receive the user communication terminal signals, meanwhile, the analysis of the signal-to-noise ratio of the terminal signals and the detection of the field intensity of the terminal signals are completed, and the processing is carried out according to the following principle after the signal data are received and checked:

1. the simulcast base station with the selected downlink time slot directly transmits the signal data received from the user communication terminal on the selected downlink time slot;

2. and the simulcast base station with the previous-hop simulcast base station transmits the signal data received from the user communication terminal on the uplink time slot of the random access application.

3. The co-broadcast base station without the non-selected downlink time slot and the last-hop co-broadcast base station is an independent base station, and can directly forward the signal data received from the user communication terminal without transmitting to a wireless link.

4. And all simulcast base stations monitor and receive the signal data of all uplink/downlink time slots at the same time, select optimal signal data for caching according to the signal-to-noise ratio and the field intensity value in the signal data, and then forward the signal data through the wireless access subsystem according to the corresponding time slots.

The safety guarantee of a specific route is realized by the aid of a machine-fixed die type wireless communication system, namely a vehicle-mounted self-adaptive wireless link simulcast system and a fixed wired link trunking system are required, wherein the vehicle-mounted self-adaptive wireless link simulcast system is used for guaranteeing the communication of a motorcade, and the fixed wired link trunking system is used for the communication distributed and controlled along the line.

The adaptive wireless link simulcast system is generally composed of a command vehicle (ZH 0), more than 3 motor communication vehicles (JD 1, JD2, JD3 respectively) and a plurality of user communication terminals, wherein the command vehicle is configured with a scheduling management center and 1 single-channel vehicle-mounted simulcast base station, the motor communication vehicles are configured with 1 single-channel vehicle-mounted simulcast base station, and the user communication terminals can be handheld stations or vehicle-mounted stations.

Dispatch management center composition as shown in fig. 4, a particular route security scenario typically does not configure location services.

The simulcast base station is composed of 1 set of wireless link subsystem, 1 set of single-channel wireless access subsystem, 1 master station, 1 slave station controller, 1 power supply, 1 cabinet assembly with motherboard and backboard, as shown in fig. 5. The antennas of the wireless link subsystem and the wireless access subsystem are vehicle-mounted antennas, the antenna selection frame of the wireless link subsystem is arranged at a higher position of the vehicle roof, and the antenna frame of the wireless access subsystem is arranged at a lower position of the vehicle tail.

Allocation of link time slots and transmission of simulcast signals

The allocation of link slots and the propagation of simulcast signals are described below in terms of two exemplary scenarios that vary throughout the security process.

Scene one: non-shielding straight line section

The link slot assignments are shown in fig. 7. The command vehicle ZH0 is started first, all downlink time slots 1,3,5 and 7 are idle, and 1 is selected as a link downlink time slot; when the motor communication vehicle JD3 is started, the downlink time slot 1 is detected to be occupied, 3,5 and 7 are idle, and 3 is selected as a link downlink time slot; since automotive communication vehicle JD2 can still receive the link signal of automotive communication vehicle JD3, it is detected that downlink time slots 1 and 3 are occupied and 5 and 7 are idle at the time of starting, so 5 is selected as the link downlink time slot; motor vehicle JD1 may receive the link signals of motor vehicle JD2 and command vehicle ZH0, but may not receive the link signals of motor vehicle JD3, and may detect that downlink timeslots 1 and 5 are occupied, and that 3 and 7 are idle at start-up, so that a 3-bit link downlink timeslot is selected to be the same as JD3, i.e., the link timeslots may be multiplexed when there is no overlap.

The link time slots of the adaptive wireless link simulcast system are distributed as shown in fig. 7, the simulcast signal transmission of the packet session initiated by the U2 is shown in fig. 8, the simulcast signal transmission of the U2 to the U1 and the U3 in the packet session is shown in fig. 9, and the simulcast signal transmission of the U1 to the U2 and the U3 in the packet session is shown in fig. 10, wherein DSn represents that the downlink time slot is n.

The procedure for U2 to initiate a packet session is as follows:

1. u2 sends packet session request, and retransmits 3 times;

2. ZH0 and JD2 receive the packet session request of U2 at the same time, start timer T1, timeout time is 3 slot cycle time, and forward the packet session request (with signal quality parameters) in own downlink slots (DS 1 and DS 5), retransmit 3 times;

3. JD1 and JD3 receive the packet session requests of JD2 and ZH0 in link slots (DS 1 and DS 5) and forward the packet session requests in their own downlink slots (both DS 3), respectively; JD2 receives the packet session request forwarded by ZH0 in link slot DS1, extracts the signal quality information of U2 received by ZH0, and extracts the signal quality information of U2 received by JD2 when ZH0 receives the packet session request forwarded by JD2 in link slot DS 5. When the timer T1 is overtime, ZH0 and JD2 only enable the base station with better received U2 signal quality to answer the packet session request to U2 by comparing the received U2 signal quality information, and retransmit for 3 times. Such as: if the signal quality of U2 received by ZH0 is better than that of U2 received by JD2, only ZH0 replies the packet session request to U2, and JD2 does not reply; whereas only JD2 replies to U2 with a packet session request, ZH0 does not reply.

After receiving the response of the packet session request, U2 enters a session state.

The simulcast signaling procedure from U2 to U1 and U3 during the packet session is as follows:

1. u2 transmits packet session signal data. The signal data frame carries a signal data frame number SDN (Signal Data Number), a source base station number BSN (Base Station Number), and a radio access forwarding slot number TSN (Transmit Slot Number). The signal data frame number SDN is generated at the user communication terminal side U2, and the source base station number BSN and the radio access forwarding timeslot number TSN are generated at the base station sides (ZH 0 and JD 2) that receive the U2 signal data. The wireless access forwarding time slot number TSN is generated by a receiving base station (ZH 0 and JD 2) according to the current wireless access time slot number WASN (wireless access slot number) and the base station parameter time slot offset SO (slot offset) when the user communication terminal U2 signal data frame is received, and TSN=WASN+SO; forwarding base stations JD1 and JD3 do not generate any numbers;

2. ZH0 and JD2 receive packet session signal data from U2 at the same time and forward in their own downlink time slots (DS 1 and DS 5), respectively.

3. After step 2, JD1, JD2, JD3 and ZH0 receive the packet session signal data of ZH0 or JD 2. JD1, JD2, JD3 and ZH0 start forwarding the wireless link channel and session signal data received by the wireless access channel at the wireless access channel when the wireless access forwarding slot number TSN.

The simulcast signaling procedure for U1 to U2 and U3 during the packet session is as follows:

1. u1 transmits packet session signal data. The signal data frame carries a signal data frame number SDN (signal data number), a source base station number BSN (basestation number), and a radio access forwarding slot number TSN (transmit slot number). The signal data frame number SDN is generated at the user communication terminal side U2, and the source base station number BSN and the radio access forwarding timeslot number TSN are generated at the base station sides (JD 1 and JD 2) that receive the U2 signal data. The wireless access forwarding time slot number TSN is generated by the receiving base stations (JD 1 and JD 2) according to the current wireless access time slot number WASN (wireless access slot number) and the base station parameter time slot offset SO (slot offset) when the user communication terminal U2 signal data frame is received, and TSN=WASN+SO; the forwarding base stations ZH0 and JD3 do not generate any numbers;

2. JD1 and JD2 receive packet session signal data from U1 at the same time and forward in their own downlink time slots (DS 3 and DS 5), respectively;

3. after step 2, JD1, JD2, JD3 and ZH0 receive the packet session signal data of JD1 or JD 2. JD1, JD2, JD3 and ZH0 start forwarding the wireless link channel and session signal data received by the wireless access channel at the wireless access channel when the wireless access forwarding slot number TSN.

In the packet session process, the optimized forwarding rule of the wireless link channel:

1. when a session starts, the JD1 and the JD2 immediately forward after receiving the session signal data of the U1; after the comparison of 3 time slot periods, if the signal quality received by the base station through the wireless access channel is poor, the signal data received by the base station through the wireless access channel is stopped to be forwarded;

2. during the conversation process: if the signal quality of the base station which pauses the forwarding becomes better after the comparison of 3 time slot periods, starting to forward the signal data received by the base station through the wireless access channel again; in contrast, if the signal quality of the base station being forwarded becomes worse after the comparison of 3 slot periods, the forwarding of the signal data received by the base station through the radio access channel is suspended.

In the packet session process, the optimized forwarding rule of the wireless access channel:

the signal data frame numbers SDN are the same signal data, and the wireless access channel only caches and forwards the frame signal data with better signal quality. As in JD2 in fig. 9, signal data forwarded by JD1 may be received from a radio link channel, or signal data of U1 may be received from a radio access channel, and any numbered signal data frame only buffers signal data of a frame with better signal quality from a plurality of sources.

According to the optimized forwarding rule, the signal data of any number received by the user communication terminal can be ensured to be the source with better signal quality, and the phenomenon of discontinuous conversation or conversation interruption can be reduced or avoided.

Scene II: non-shielding turning road section

As shown in fig. 7, when a particular line safety assurance communication fleet travels to an unobstructed corner, a link slot allocation conflict as shown in fig. 11 may occur: since the curve is clear and the straight line distance between JD1 and JD3 is reduced, JD1 and JD3 may receive each other's radio link signals, and the assigned radio link timeslots are the same, which may cause co-channel interference.

When the time slot collision brings the same-frequency interference, the same-frequency interference detection is needed to assist in reallocating the link time slot. As shown in fig. 11, when co-channel interference occurs in JD1 and JD3, both JD2 and ZH0 can detect and determine whether interference exists through link slot 3. The detection and determination principle is as follows:

1. when JD2 and ZH0 can detect signals on link slot 3 in 3 consecutive slot periods, but the signal data check fails, the collision slot number 3 and the base station number (JD 1 and JD 3) currently selected slot 3 as the downlink slot can be respectively announced in its own downlink slot;

2. When JD1 and JD3 receive conflicting time slot number signal data frames in time slots 1 and 5, respectively, the base station with the larger number needs to reselect the downlink time slot according to the base station number in the signal data frame. Assuming JD3 has a base station number greater than JD1, it can be detected that downlink timeslots 1, 5 and 3 are occupied at this time, and then 7 is reselected as the link downlink timeslot. The link time slot reassignment is followed by the illustration of fig. 12.

The link time slots of the adaptive wireless link simulcast system are allocated as shown in fig. 12, the simulcast signal transmission of the packet session initiated by U2 is shown in fig. 13, the simulcast signal transmission from U2 to U1 and U3 in the packet session is shown in fig. 14, and the simulcast signal transmission from U1 to U2 and U3 in the packet session is shown in fig. 15, wherein DSn indicates that the downlink time slot is n. The procedure for U2 to initiate a packet session is as follows:

1. u2 sends packet session request, and retransmits 3 times;

2. ZH0 and JD2 receive the packet session request of U2 at the same time, start timer T1, timeout 3 slot cycle times, and notify packet session request (with signal quality parameter) in own downlink slots (DS 1 and DS 5) at the same time, retransmit 3 times;

3. JD1 and JD3 receive packet conference requests of JD2 and ZH0 in time slots (DS 1 and DS 5) and forward packet session requests in their own downlink time slots (DS 3 and DS 7), respectively; the base station with better signal quality for receiving U2 in ZH0 and JD2 replies to U2 with packet session request and retransmits 3 times when timer T1 expires.

ZH0 receives the packet session request forwarded by JD2 in the link slot DS5, extracts the signal quality information of the U2 received by JD2, JD2 receives the packet session request forwarded by JD1 in the link slot DS5, and extracts the signal quality information of the U2 received by ZH 0. When the timer T1 is overtime, ZH0 and JD2 only enable the base station with better received U2 signal quality to answer the packet session request to U2 by comparing the received U2 signal quality information, and retransmit for 3 times. Such as: if the signal quality of U2 received by JD2 is better than that of U2 received by ZH0, only JD2 replies the packet session request to U2, and ZH0 does not reply; whereas only ZH0 replies to U2 with a packet session request, JD2 does not reply.

1. u2 transmits packet session signal data. The signal data frame carries a signal data frame number SDN (signal data number), a source base station number BSN (basestation number), and a radio access forwarding slot number TSN (transmit slot number). The signal data frame number SDN is generated at the user communication terminal side U2, and the source base station number BSN and the radio access forwarding timeslot number TSN are generated at the base station sides (ZH 0 and JD 2) that receive the U2 signal data. The wireless access forwarding time slot number TSN is generated by a receiving base station (ZH 0 and JD 2) according to the current wireless access time slot number WASN (wireless access slot number) and the base station parameter time slot offset SO (slot offset) when the user communication terminal U2 signal data frame is received, and TSN=WASN+SO; forwarding base stations JD1 and JD3 do not generate any numbers;

2. ZH0 and JD2 receive packet session signal data from U2 at the same time and forward in their own downlink time slots (DS 1 and DS 5), respectively;

the signal data frame numbers SDN are the same signal data, and the wireless access channel only caches and forwards the frame signal data with better signal quality. As in JD2 in fig. 10, signal data forwarded by JD1, JD3 and ZH0 can be received from a radio link channel, and signal data of U1 can be received from a radio access channel, and any numbered signal data frame only buffers signal data of a frame with better signal quality in a plurality of sources.

Those skilled in the art will appreciate that all or part of the flow of the methods of the embodiments described above may be accomplished by way of a computer program to instruct associated hardware, where the program may be stored on a computer readable storage medium. Wherein the computer readable storage medium is a magnetic disk, an optical disk, a read-only memory or a random access memory, etc.

The present invention is not limited to the above-mentioned embodiments, and any changes or substitutions that can be easily understood by those skilled in the art within the technical scope of the present invention are intended to be included in the scope of the present invention.

Claims

1. An adaptive wireless link simulcasting method, comprising:

when a first motor vehicle base station JD1, a second motor vehicle base station JD2, a command vehicle base station ZH0 to an Nth motor vehicle base station JDN are positioned on an unobstructed straight road section or an unobstructed turning road section, a first user communication terminal U1 is arranged between the first motor vehicle base station JD1 and the second motor vehicle base station JD2, a second user communication terminal U2 is arranged between the command vehicle base station ZH0 and the second motor vehicle base station JD2, and an Nth user communication terminal is arranged between an N-1 motor vehicle base station JDN-1 and the Nth motor vehicle base station JDN, wherein N is a positive integer greater than 2;

dynamically allocating the link time slots of the self-adaptive wireless link simulcast system, wherein when the same-frequency interference is brought by the time slot conflict, the auxiliary link time slots are reallocated through the same-frequency interference detection;

initiating a packet session request through a specific user communication terminal of the first to nth user communication terminals U1 to UN and entering a packet session procedure after receiving a packet session request reply, wherein when the specific user communication terminal is the second user communication terminal U2, initiating a packet session request through a specific user communication terminal of the first to nth user communication terminals U1 to UN further comprises: transmitting a packet session request through the second user communication terminal U2 and retransmitting 3 times; simultaneously receiving a packet session request of the second user communication terminal U2 through a first adjacent base station, starting a timer and forwarding the packet session request in a downlink time slot of the first adjacent base station, wherein the first adjacent base station is the command vehicle base station ZH0 and the second motor vehicle base station JD2 which are adjacent to the second user communication terminal U2; receiving, by the first mobile communication vehicle base station JD1 and the nth mobile communication vehicle base station JDN, a packet session request of the first neighboring base station in link timeslots DS1 and DS5, and forwarding the packet session request in a downlink timeslot DS3 of the first mobile communication vehicle base station JD1 and a downlink timeslot DS3 of the nth mobile communication vehicle base station JDN or a reselected link downlink timeslot, respectively, wherein when the timer T1 expires, the first neighboring base station receives a base station with better signal quality of the second user communication terminal U2, sends a packet session request response to the second user communication terminal U2, and retransmits 3 times; and

And in the packet session process, transmitting a synchronous signal to other user communication terminals from the first user communication terminal U1 to the Nth user communication terminal UN through the specific user communication terminal.

2. The adaptive wireless link simulcasting method of claim 1, wherein dynamically allocating link timeslots of an adaptive wireless link simulcasting system when said first to nth automotive base stations JD1 to ZH0 are located on said unobstructed straight line segment comprises:

when the command vehicle base station ZH0 is started first, detecting that downlink time slots 1, 3, 5, … and 2N-1 are idle time slots, and selecting 1 as a link downlink time slot of the command vehicle base station ZH 0;

when the Nth motor communication vehicle base station JDN is started, detecting that the downlink time slot 1 is occupied and the downlink time slots 3, 5, … and 2N-1 are idle time slots, and selecting 3 as a link downlink time slot of the Nth motor communication vehicle base station JDN;

since the second mobile communication vehicle base station JD2 can receive the link signal of the mobile communication vehicle JD3, it is detected that the downlink time slots 1 and 3 are occupied and the downlink time slots 5, …, 2N-1 are idle time slots, and 5 is selected as the link downlink time slot of the second mobile communication vehicle base station JD 2; and

When the first vehicle base station JD1 is able to receive the link signals of the second vehicle base station JD2 and the command vehicle base station ZH0, but not the link signal of the nth vehicle JDN, it detects that downlink timeslots 1 and 5 are occupied and downlink timeslots 3 and 2N-1 are idle timeslots, and selects 3 as the downlink timeslot of the first vehicle base station JD 1.

3. The adaptive wireless link simulcasting method of claim 2, wherein when the first vehicle base station JD1, the second vehicle base station JD2, the director vehicle base station ZH0 to the nth vehicle base station JDN travel to the unobstructed road segment, a linear distance between the first vehicle base station JD1 and the nth vehicle base station JDN decreases, the first vehicle base station JD1 and the nth vehicle base station JDN being capable of receiving each other's wireless link signals and assigned wireless link timeslots being the same such that co-channel interference is generated between the first vehicle base station JD1 and the nth vehicle base station JDN.

4. The adaptive radio link simulcasting method of claim 3, wherein generating co-channel interference between the first automotive base station JD1 and the nth automotive base station JDN further comprises:

When the second motor communication vehicle base station JD2 and the command vehicle base station ZH0 detect signal data on the link time slot 3 in 3 continuous time slot periods, but check of the detected signal data fails, respectively notifying a conflict time slot number 3 and a base station number of which the currently selected time slot 3 is a downlink time slot in the own downlink time slot; and

when the first and the nth motor vehicle base stations JD1 and JDN receive signal data frames with conflicting time slot numbers in time slots 1 and 5, respectively, reselecting a link downlink time slot for the nth motor vehicle base station JDN with larger number according to the base station number in the signal data frame.

5. The adaptive radio link simulcasting method according to claim 1, wherein when said timer T1 expires, said one of said first neighboring base stations which has received said second user communication terminal U2 with a better signal quality, transmitting a packet session request reply to said second user communication terminal U2 comprises:

receiving a packet session request of a second user communication terminal U2 forwarded by the command vehicle base station ZH0 through the second motor communication vehicle base station JD2 in a link time slot DS1 and extracting signal quality information of the packet session request forwarded by the command vehicle base station ZH 0;

Receiving a packet session request of a second user communication terminal U2 forwarded by the second motor communication vehicle base station JD2 in a link time slot DS5 through the command vehicle base station ZH0 and extracting signal quality information of the packet session request forwarded by the second motor communication vehicle base station JD 2;

when the timer is overtime, the command vehicle base station ZH0 and the second motor vehicle base station JD2 respectively compare the signal quality of the packet session request of the second user communication terminal U2 directly received with the signal quality of the packet session request forwarded by the second motor vehicle base station JD2 or the command vehicle base station ZH0 previously extracted; and

and determining the base station with better signal quality in the packet session requests directly received by the command vehicle base station ZH0 and the second motor communication vehicle base station JD2 according to the comparison result, and sending a packet session request response to the second user communication terminal U2.

6. The adaptive radio link simulcasting method according to claim 1, wherein synchronizing signal transmission to other user communication terminals among the first to nth user communication terminals U1 to UN through the specific user communication terminal during the packet session comprises:

Transmitting packet session signal data through the specific user communication terminal, wherein the packet session signal data comprises a plurality of signal data frames, and the signal data frames comprise a signal data frame number SDN, a source base station number BSN and a wireless access forwarding time slot number TSN, and the specific user communication terminal comprises a first user communication terminal U1 or a second user communication terminal U2;

receiving packet session signal data from the second user communication terminal U2 or the first user communication terminal U1 through the first neighboring base station or a second neighboring base station simultaneously, and forwarding packet session information data in own downlink timeslots DS1 and DS5 or DS3 and DS5, respectively, wherein the second neighboring base station is the first motor vehicle base station JD1 and the second motor vehicle base station JD2 neighboring the first user communication terminal U1;

and receiving packet session signal data of one or two base stations of the first adjacent base station or the second adjacent base station through the first motor communication vehicle base stations JD1 to N motor communication vehicle base stations JDN and the command vehicle base station ZH0, and then forwarding the packet session signal data received by the wireless link channel and the wireless access channel through the first motor communication vehicle base stations JD1 to N motor communication vehicle base stations JDN and the command vehicle base station ZH0 in a wireless access channel when the wireless access forwarding time slot number TSN is reached.

7. The adaptive wireless link simulcasting method of claim 6,

generating the signal data frame number SDN by the second user communication terminal U2 or the first user communication terminal U1;

generating, by the first neighboring base station or the second neighboring base station, the source base station number BSN and the radio access forwarding time slot number TSN, where the first neighboring base station or the second neighboring base station generates, based on a current radio access time slot number WASN and a base station parameter time slot offset SO, a radio access forwarding time slot number TSN according to a signal data frame received from the second user communication terminal U2 or the first user communication terminal U1, where the radio access forwarding time slot number tsn=current radio access time slot number wasn+base station parameter time slot offset SO.

8. An adaptive wireless link simulcast system, comprising:

a plurality of base stations including a first motor communication vehicle base station JD1, a second motor communication vehicle base station JD2, a command vehicle base station ZH0 to an Nth motor communication vehicle base station JDN which are positioned in order on an unobstructed straight road section or an unobstructed turning road section,

a plurality of user communication terminals comprising: a first user communication terminal U1 located between the first motor vehicle base station JD1 and the second motor vehicle base station JD2, a second user communication terminal U2 located between the command vehicle base station ZH0 and the second motor vehicle base station JD2, and an nth user communication terminal located between an nth-1 motor vehicle base station JDN-1 and the nth motor vehicle base station JDN, wherein N is a positive integer greater than 2;

The time slot allocation module is used for dynamically allocating the link time slots of the self-adaptive wireless link simulcast system, wherein when the same-frequency interference is brought by the time slot conflict, the auxiliary link time slots are reallocated through the same-frequency interference detection;

a packet session request and response module, configured to initiate a packet session request through a specific user communication terminal from among the first user communication terminal U1 to the nth user communication terminal UN, and enter a packet session procedure after receiving a packet session request response, where when the specific user communication terminal is the second user communication terminal U2, initiating a packet session request through a specific user communication terminal from among the first user communication terminal U1 to the nth user communication terminal UN further includes: transmitting a packet session request through the second user communication terminal U2 and retransmitting 3 times; simultaneously receiving a packet session request of the second user communication terminal U2 through a first adjacent base station, starting a timer and forwarding the packet session request in a downlink time slot of the first adjacent base station, wherein the first adjacent base station is the command vehicle base station ZH0 and the second motor vehicle base station JD2 which are adjacent to the second user communication terminal U2; receiving, by the first mobile communication vehicle base station JD1 and the nth mobile communication vehicle base station JDN, a packet session request of the first neighboring base station in link timeslots DS1 and DS5, and forwarding the packet session request in a downlink timeslot DS3 of the first mobile communication vehicle base station JD1 and a downlink timeslot DS3 of the nth mobile communication vehicle base station JDN or a reselected link downlink timeslot, respectively, wherein when the timer T1 expires, the first neighboring base station receives a base station with better signal quality of the second user communication terminal U2, sends a packet session request response to the second user communication terminal U2, and retransmits 3 times; and

And the packet session module is used for transmitting a synchronous signal to other user communication terminals from the first user communication terminal U1 to the Nth user communication terminal UN through the specific user communication terminal in the packet session process.

9. The adaptive wireless link simulcast system of claim 8, wherein when the first to nth motor vehicle base stations JD1 to ZH0 are located on the unobstructed straight road segment, the time slot allocation module is configured to: