TWI657688B - Time division multiplexing channel structure and time division multiplexing communication method using the same - Google Patents

Abstract

A time division multiplex channel structure includes a synchronization signal representing a start of a cycle and at least one registered time slot string and at least one unregistered time slot string and an indefinite number of dynamic time slots. The sync signal is used as the start of a cycle to synchronize the zero-zero clock zeros. Each registered time slot sequence is composed of a plurality of consecutive registered time slots. These registered time slots are assigned to a plurality of corresponding registered users. Each unregistered time slot sequence is composed of a plurality of consecutive unregistered time slots, which are reserved for use in the first listening and sending mechanism, and an indefinite number of dynamic time slots are used as the time slots used by the master control device.

Description

Time-division multiplex channel structure and time-sharing multiplex data transmission method

The invention relates to a time-division multiplex channel structure and a time-division multiplex data transmission method thereof, in particular to a time-sharing with a reserved time slot for a listen-before-talk (LBT) mechanism or an emergency mode. Multi-channel structure and its time-division multiplex data transmission method.

Time-Division Multiplexing (TDM) is a digital or analog multiplex technology that allows more than two signals or streams to be transmitted simultaneously on a single communication channel, acting as subchannels of the same communication channel. However, physically, these signals or data streams take turns occupying physical channels, and their occupation time is divided into segments of periodic cycles (time slots), and the length of each period is fixed.

The traditional time-division multiplex data transfer method assigns each time slot of the cycle to a fixed user. Therefore, this transmission method cannot respond immediately when there is an emergency and there is a need for rapid transmission. In addition, due to the circulation cycle of these time slots on the communication channel The fixed period is not conducive to the use of communication endpoints for certain long periods (eg, greater than the synchronization signal period on the communication channel). Therefore, the traditional time-multiplexed data transmission method cannot flexibly combine long-term and short-period communication endpoints.

In view of this, one of the main objects of the present invention is to provide a time-division multiplex channel structure and a time-division multiplex data transmission method thereof, and to retain a time slot and use a listen-before-talk (LBT) mechanism. On the one hand, some nodes can be provided with a shorter time delay to respond to emergencies, and on the other hand, to some endpoints with longer time periods and not suitable for occupying fixed-cycle slots. The slot can be used to help elastically combine the endpoints of different periodic properties.

The present invention provides a time division multiplex (TDM) channel structure including at least one registered time slot string and at least one unregistered time slot. Each registered time slot sequence is composed of a plurality of consecutive registered time slots, which are assigned to a plurality of registered users. Each unregistered time slot sequence is composed of a plurality of consecutive unregistered time slots. The unregistered time slot sequence corresponds to the at least one registered time slot string, and is reserved for use in the first listening and sending mechanism or emergency mode.

In one embodiment of the time division multiplex channel structure, the unregistered time slot string is used to provide unregistered user transmission data. Moreover, in a preferred embodiment, the unregistered time slot string is used to provide a registered user to transmit data in an emergency.

In one embodiment of the time division multiplex channel structure, the unregistered time slot string is located before the corresponding registered time slot string according to the time domain.

In one embodiment of the time division multiplex channel structure, the unregistered time slot string is located after the corresponding registered time slot string according to the time domain.

In one embodiment of the time division multiplex channel structure, a packet transmitted using the time slot includes a header to represent one of the at least three transmission modes as the transmission mode. Corresponding to at least three different delay times to perform a listen-and-forward mechanism. In a preferred embodiment, the transmission modes include a standard mode, an unregistered mode, and an emergency mode. The delay time corresponding to the emergency mode is shorter than the delay time corresponding to the unregistered mode, and the delay time corresponding to the unregistered mode is shorter than the standard mode. Corresponding delay time. The standard mode packet uses the slotted transmission when registering, the unregistered mode packet uses the unregistered slotted transmission, and the emergency mode packet uses the time slot transmission with the closest time.

The invention also provides a time division multiplex data transmission method. First, provide a channel. Then, on the channel, at least one registered time slot string is divided according to the time domain, and each registered time slot string is composed of a plurality of registered time slots, and the registered time slots are allocated to a plurality of registered users. . Then, in the channel, at least one unregistered time slot string is divided according to the time domain, and each unregistered time slot sequence is composed of a plurality of unregistered time slots, which are reserved for use in the first listening and sending mechanism or in the emergency mode.

The invention also provides a time division multiplex data transmission party law. First, at least three different transmission modes are defined for the channel, which correspond to at least three different delay times. Then, a transmission mode is selected, and the state of the channel is heard according to the delay time corresponding to the transmission mode to decide whether to send the data.

The specific embodiments of the present invention will be further described by the following examples and drawings.

Ts‧‧‧Synchronous time slot

UX1...UXn‧‧‧ not registered slot

Tm‧‧ dynamic time slot

Tj‧‧‧ joined the request slot

DL0, DL1, DL2‧‧‧ delay time

Nr‧‧‧ random number

LBT‧‧‧ time interval

TX‧‧‧ time interval

1 is a flowchart of a time division multiplex data transmission method according to an embodiment of the present invention; and a second diagram is a schematic diagram of a preferred embodiment of a channel structure corresponding to the time division multiplex data transmission method of the first figure; 3 is a flow chart of a time division multiplex data transmission method according to another embodiment of the present invention; and a fourth diagram is a schematic diagram of a preferred embodiment of a channel structure corresponding to the time division multiplex data transmission method of the third figure.

Specific embodiments of the present invention will be described in more detail below with reference to the drawings. Advantages and features of the present invention will be apparent from the description and appended claims. It should be noted that the drawings are all in a very simplified form and both use non-precise proportions, and are only for convenience and clarity to assist the purpose of the embodiments of the present invention.

The first figure is a time-sharing multi-pay according to an embodiment of the present invention. Flow chart of the material transfer method. As shown in the figure, the time division multiplex data transmission method includes the following steps.

First, as shown in step S110, a channel is provided. Next, as shown in step S120, on the channel, at least one registered time slot string is divided according to the time domain. Each registered time slot sequence is composed of a plurality of consecutive registered time slots assigned to a plurality of corresponding registered nodes (i.e., registered users). In addition, as shown in step S130, in the channel, at least one unregistered time slot string is divided according to the time domain. These unregistered time slot sequences respectively correspond to the respective registered time slot strings (or the registered time slots in each registered time slot string), and are reserved for use by the first listening and sending mechanism. In the embodiment of the first figure, the foregoing steps S120 and S130 are performed sequentially, but the present invention is not limited thereto.

Please also refer to the second figure, which shows a preferred embodiment of the channel structure corresponding to the time division multiplex data transmission method of the first figure. The figure shows the channel structure in a time domain. As shown in the figure, the channel structure includes a synchronization time slot Ts, at least one registered time slot string, at least one unregistered time slot string UX1...UXn, an indefinite number of dynamic time slots Tm and a join request (request) Join) time slot Tj. A plurality of time slots between the two synchronization time slots Ts constitute one cycle. In this embodiment, there are n cycle cycles of the registered time slot series and n corresponding unregistered time slot strings UX1 . . . UXn between two adjacent synchronization time slots Ts. The number of these registered time slot strings and unregistered time slot strings UX1...UXn can be adjusted as needed.

Synchronization time slot Ts is used to ensure the synchronization of all nodes to transmit data, avoiding the cumulative error of the clock. (accumulated error) is generated. For example, each node can ensure the clock synchronization by detecting the synchronization signal in the synchronization time slot.

Each registered time slot is composed of a plurality of consecutive registered time slots and is assigned to a plurality of corresponding registered nodes. These registered nodes are usually slave nodes. In this way, in the registered slot sequence, each registered node can use its fixed registered time slot to transmit uplink data in a time division multiplexing manner.

Each of the registered time slot sequences corresponds to one unregistered time slot string UX1...UXn. These unregistered time slot strings UX1...UXn are reserved for use by the listener and send back mechanism. These unregistered time slot strings UX1...UXn are composed of a plurality of consecutive unregistered time slots. Further, these unregistered time slot strings UX1...UXn can provide unregistered user transmission data. Moreover, in a preferred embodiment, the unregistered time slot strings UX1...UXn may also provide the registered user to transmit data in an emergency state. For example, if the registered user has insufficient registered slot width, or the registered user cannot wait for the registered time slot of the next cycle, the unregistered time slot can be used to transmit the data. In the present embodiment, the unregistered time slot strings UX1 ... UXn are adjacent to the previous one of the corresponding registered time slot strings. However, the invention is not limited thereto. In another embodiment, the unregistered time slot strings UX1...UXn may also be located after the corresponding registered time slot string, and before the next registered time slot string.

Secondly, in a preferred embodiment, the width of the unregistered slot strings UX1...UXn can be adjusted depending on the size of the network or the number of network users. For example, if the network is large or the network The number of users is large, which means that the possibility of using the slot strings UX1...UXn when not registered is high, and the width of the unregistered slot strings UX1...UXn can be increased to meet the demand.

The dynamic time slot Tm corresponds to the downlink packet transmitted by the master endpoint, and can change its number or width according to the amount of data to be transmitted and the object to be transmitted. Therefore, the dynamic time slot Tm is required only when the master node needs to transmit the downlink packet to other nodes, and the slot Tm may be omitted according to actual requirements. When the request is added, the slot Tj corresponds to the transmission of the required request packet, and the slot Tj at this time may be omitted according to actual needs.

This embodiment is described by taking a single channel as an example. However, in practical applications, the time-multiplexed data transmission system can use a larger number of channels for data transmission, and each channel can selectively adopt the technology provided by the present invention. Moreover, the time-division multiplexed data transmission method provided by the embodiment is applicable to other network transmission technologies, such as time division multiplexing, which are derived from time division multiplexing technology, in addition to the time division multiplexing technology field. Pick-up (TDMA) technology.

The third figure is a flow chart of a time division multiplex data transmission method according to another embodiment of the present invention. As shown in the figure, the time division multiplex data transmission method includes the following steps.

First, in step S210, at least three different transmission modes are defined for the channels, the transmission modes corresponding to at least three different delay times. Then, in step S220, a transmission mode is selected, and the state of the channel is heard according to the delay time corresponding to the transmission mode to decide whether to send the data.

Please also refer to the fourth picture, which corresponds to the third A preferred embodiment of the channel structure of the time division multiplexed data transmission method of the figure. In this embodiment, there are a total of three transmission modes, namely a standard mode, an unregistered mode, and an emergency mode, corresponding to three different delay times. The delay time DL0 corresponding to the emergency mode is shorter than the delay time DL1 corresponding to the unregistered mode, and the delay time DL1 corresponding to the unregistered mode is shorter than the delay time DL2 corresponding to the standard mode.

Further, taking the unregistered mode as an example, after the slave node confirms that the packet to be transmitted belongs to the unregistered mode, it waits for a delay time DL1 to perform the first listening and sending mechanism. More precisely, the slave node performs channel activity detection (CAD) after waiting for the delay time DL1, that is, the action of listening to the post-feed mechanism first, such as detecting the channel signal strength to confirm whether the channel is idle. (empty), to determine whether the channel can be used to transfer data. The LBT interval in the figure corresponds to this "listening" action. After confirming that the channel is available for use, the data will be transmitted using the connected TX interval.

It should be noted that, in this embodiment, since the emergency mode delay time DL0 is the shortest, the emergency mode normally cannot detect that the other mode packets are being transmitted. Secondly, as shown in the figure, in the unregistered mode and the emergency mode, after the slave node waits for the delay time DL1, DL0, a random number Nr is sent first, that is, a random delay is executed, and then the first listen is performed. Send mechanism. This random number Nr can ensure that there is a time difference between the first mode and the subsequent communication mechanism communication to prevent conflicts.

Please refer to the channel structure of the second figure at the same time. The standard mode packet of this embodiment can be transmitted by using the slot string during registration, and is not registered. The mode packet is transmitted using the unregistered slot sequence, and the emergency mode packet is transmitted using the time slot with the closest time.

After the slave node confirms the mode of the transmission to be performed, the slave node selects the packet header representing the transmission mode among a plurality of different headers corresponding to the transmission modes according to the transmission mode to be performed. File, and wait for the corresponding delay time before transmitting the packet. After receiving the packet, the receiving end (usually the master node) can confirm the transmission mode by the packet header file, and report the upper layer control unit to record the integrity.

Through the time-division multiplex channel structure and the time-division multiplex data transmission method provided by the invention, on the one hand, some end points can be provided with shorter time delays to respond to emergencies, and on the other hand, some can also be compared. The long period of time is not suitable for occupying the fixed period. The end of the slot provides an additional time slot, which helps to elastically combine the endpoints of different periodic properties.

The above is only a preferred embodiment of the invention and is not intended to limit the invention. Any changes in the technical means and technical contents disclosed in the present invention may be made by those skilled in the art without departing from the technical means of the present invention. The content is still within the scope of protection of the present invention.

Claims (15)

A time division multiplexing (TDM) channel data structure, the channel data structure comprising: at least one registered time slot string, the registered time slot string being composed of a plurality of consecutive registered time slots, The registered time slots are assigned to a plurality of registered users; and at least one unregistered time slot string corresponding to the at least one registered time slot string is reserved for the Listening and Forwarding Mechanism (LBT) Or emergency mode use; wherein a packet transmitted by the unregistered slot sequence includes a header to represent a selected transmission mode from one of the at least two transmission modes, the transmission modes corresponding to at least Two different delay times are used to perform the listen-and-forward mechanism. For example, the time division multiplex channel data structure of claim 1 is wherein the unregistered time slot string is used to provide unregistered user transmission data. For example, the time division multiplex channel data structure of claim 2, wherein the unregistered time slot string is used to provide the registered users to transmit data in an emergency state. For example, the time division multiplex channel data structure of claim 1 is wherein the unregistered time slot string is located in front of the corresponding registered time slot string according to the time domain. For example, in the time division multiplex channel data structure of claim 1, wherein the unregistered time slot string is located after the corresponding registered time slot string according to the time domain. The time division multiplex channel data structure of claim 1, wherein the transmission modes include a standard mode, an unregistered mode, and the emergency mode, wherein the emergency mode corresponds to the delay time being shorter than the unregistered mode. The delay time, the delay time corresponding to the unregistered mode is shorter than the delay time corresponding to the standard mode. A time-multiplexed data transmission method includes: dividing, on a channel, at least one registered time slot string according to a time domain, wherein the at least one registered time slot string is composed of a plurality of registered time slots, and the The registration time slot is assigned to a plurality of registered users; in the channel, at least one unregistered time slot string is divided according to the time domain, corresponding to the at least one registered time slot string, reserved for the first listening and sending mechanism or Emergency mode use; defining at least two different transmission modes for the channel, the transmission modes corresponding to at least two different delay times; and selecting a transmission mode, and listening to the channel according to the delay time corresponding to the transmission mode Status to decide whether to send data. For example, the time-multiplexed data transmission method of claim 7 is characterized in that the unregistered time slot string is used to provide unregistered user transmission data. The time-multiplexed data transmission method of claim 8, wherein the unregistered time slot string is used to provide the registered users to transmit data in an emergency state. The time division multiplexed data transmission method of claim 7, wherein the unregistered time slot sequence is located in front of the corresponding registered time slot string according to the time domain. The time division multiplexed data transmission method of claim 7, wherein the unregistered time slot sequence is located after the corresponding registered time slot string. The time-multiplexed data transmission method of claim 7, wherein the transmission modes include a standard mode, an unregistered mode, and an emergency mode, wherein the emergency mode corresponds to the delay time being shorter than the unregistered mode corresponding to the The delay time, the delay time corresponding to the unregistered mode is shorter than the delay time corresponding to the standard mode. The time division multiplex data transmission method of claim 12, wherein the unregistered mode and the emergency mode further comprise a random number delay to prevent the same mode before listening to the state of the channel. collision. For example, the time-multiplexed data transmission method of claim 7 is characterized in that the step of listening to the state of the channel is to listen to the state of the registered time slot. For example, the time division multiplexed data transmission method of claim 7 is characterized in that the step of listening to the state of the channel is to listen to the state of the unregistered slot string.