EP-4507405-B1 - COMMUNICATION METHOD OF ELECTRONIC SHELF LABEL SYSTEM, SYSTEM, COMPUTER DEVICE AND STORAGE MEDIUM

EP4507405B1EP 4507405 B1EP4507405 B1EP 4507405B1EP-4507405-B1

Inventors

LIANG, MIN
JI, Yaping
CHEN, GENGFENG
ZHANG, GUOFENG
WANG, Yujing
ZHANG, JU
JIANG, Qi

Dates

Publication Date: 20260506
Application Date: 20240412

Claims (15)

A communication method of an electronic shelf label system comprising a server, a plurality of base stations and a plurality of electronic shelf labels, and the method comprising: determining (S101), by the server, a maximum capacity number of base stations in each of synchronization sub-networks, based on a predetermined signal transmission cycle and a synchronization frame transmission duration; constructing (S102), by the server, at least one synchronization sub-network comprising the plurality of base stations, based on the maximum capacity number of base stations and a network topological structure between the base stations; configuring (S103), by the server, an offset of each of the base stations in the corresponding synchronization sub-network based on neighboring relationships between all the base stations in each of the synchronization sub-networks, so that each of the base stations calculates synchronization frame transmission time (t11) in the predetermined signal transmission cycle based on the offset, wherein a start moment of sending a synchronization frame by a base station with an offset of i in a same synchronization sub-network is an end moment of sending a synchronization frame by a base station with an offset of i-1, and a maximum offset in the same synchronization sub-network is a sum of the number of actual base stations and M, where M is any integer; and calculating (S104), by each of the base stations, idle time (t12) in a synchronization channel, based on the synchronization frame transmission time (t11), so that each of the base stations receives a target synchronization frame sent by a superior base station in the idle time (t12) of the synchronization channel, and each of the base stations adjusts local synchronization frame transmission time (t11) thereof based on a time offset of the target synchronization frame, wherein each of the base stations has the idle time (t12) in the synchronization channel and data frame transmission time (t12) in a data channel overlap with each other.
The communication method of the electronic shelf label system according to claim 1, wherein after calculating, by each of the base stations, idle time (t12) in a synchronization channel, based on the synchronization frame transmission time (t11), so that each of the base stations receives a target synchronization frame sent by a superior base station in the idle time (t12) of the synchronization channel, the method further comprises: randomly sending, by an electronic shelf label in an out-of-step state, a synchronization request in the synchronization channel, so that a base station that receives the synchronization request sends a synchronization response signal; calculating, by the electronic shelf label in the out-of-step state, a windowing time period in which synchronization frames of all the base stations are received in the synchronization channel, based on the synchronization response signal; and obtaining, by the electronic shelf label in the out-of-step state, a synchronization base station, based on signal intensities of all the synchronization frames received in the windowing time period; and entering a synchronization state, based on a synchronization frame of the synchronization base station.
The communication method of the electronic shelf label system according to claim 2, wherein calculating, by the electronic shelf label in the out-of-step state, a windowing time period in which synchronization frames of all the base stations are received in the synchronization channel, based on the synchronization response signal comprises: calculating, by the electronic shelf label in the out-of-step state, a windowing start moment, based on a time offset for a base station with an offset of n in the synchronization response signal from a next transmission of synchronization frames; calculating, by the electronic shelf label in the out-of-step state, a windowing end moment, based on a maximum offset included in the synchronization response signal; and obtaining, by the electronic shelf label in the out-of-step state, a windowing time period in which synchronization frames of all the base stations are received in the synchronization channel, based on the windowing start moment and the windowing end moment.
The communication method of the electronic shelf label system according to claim 3, wherein calculating, by the electronic shelf label in the out-of-step state, a windowing start moment, based on a time offset for a base station with an offset of n in the synchronization response signal from a next transmission of synchronization frames comprises a calculation formula configured to calculate the windowing start moment: T k 0 = T x + offset − n ∗ t where, T k 0 represents a windowing start moment, n represents an offset in the synchronization response signal, T x represents a moment of reception of the synchronization response signal by the electronic shelf label in the out-of-step state, offset represents a time offset in the synchronization response signal, ( T x + offset ) represents a start moment of sending a synchronization frame by the base station with an offset of n, and t represents a synchronization frame transmission duration.
The communication method of the electronic shelf label system according to claim 3, wherein calculating, by the electronic shelf label in the out-of-step state, a windowing end moment, based on a maximum offset included in the synchronization response signal comprises a calculation formula configured to calculate the windowing start moment: T k 1 = T x + offset + N − n ∗ t where, T k 1 represents a windowing end moment, N represents a maximum offset in the synchronization sub-network where the base station with an offset of n is located, n represents an offset in the synchronization response signal, T x represents a moment of reception of the synchronization response signal by the electronic shelf label in the out-of-step state, offset represents a time offset in the synchronization response signal, and t represents a synchronization frame transmission duration.
The communication method of the electronic shelf label system according to claim 1, wherein after calculating, by each of the base stations, idle time (t12) in a synchronization channel, based on the synchronization frame transmission time (t11), so that each of the base stations receives a target synchronization frame sent by a superior base station in the idle time (t12) of the synchronization channel, the method further comprises: transmitting, by an electronic shelf label in an out-of-step state, an out-of-step heartbeat in the synchronization channel, so that at least one base station receiving the out-of-step heartbeat sends the out-of-step heartbeat and signal intensities of the received out-of-step heartbeat to the server; controlling, by the server, a first target base station which receives the out-of-step heartbeat with maximum signal intensity to transmit an asynchronization broadcast in an asynchronization channel; calculating, by the electronic shelf label in the out-of-step state, a windowing time period in which synchronization frames of all the base stations are received in the synchronization channel, based on an offset of sending moment of synchronization frames in a latest predetermined signal transmission cycle included in the asynchronization broadcast; and obtaining, by the electronic shelf label in the out-of-step state, a synchronization base station, based on signal intensities of all the synchronization frames received in the windowing time period; and entering a synchronization state, based on a synchronization frame of the synchronization base station.
The communication method of the electronic shelf label system according to any one of claims 1 to 6, wherein the electronic shelf label is in a sleep state at the time other than that of receiving a synchronization frame, sending a synchronization request, receiving a synchronization response signal, receiving a data frame, sending an out-of-step heartbeat and receiving an asynchronization broadcast and a windowing time period.
The communication method of the electronic shelf label system according to any one of claims 1 to 6, wherein the synchronization frame comprises a synchronization frame number, an offset of the base station, an indication bit regarding whether there is a data frame in a current predetermined signal transmission cycle, a channel for transmitting the data frame in the current predetermined signal transmission cycle, and a packet sequence number in the synchronization frame.
The communication method of the electronic shelf label system according to claim 8, further comprising: when a base station has a data frame to be sent in a next predetermined signal transmission cycle, selecting, by the base station or the server, a target channel from an idle data channel pool as a data channel for the base station to transmit the data frame; configuring the target channel in a transmission synchronization frame of the next predetermined signal transmission cycle, and enabling a plurality of electronic shelf labels synchronized with the base station to receive the data frame in the target channel; and releasing, by the base station, the target channel into the idle data channel pool, based on a transmission requirement of the data frame.
The communication method of the electronic shelf label system according to claim 1, wherein after calculating, by each of the base stations, idle time (t12) in a synchronization channel, based on the synchronization frame transmission time (t11), the method further comprises: receiving, by a base station in an out-of-step state, synchronization frames sent by other base stations in a same store within a time period exceeding the predetermined signal transmission cycle under the control of the server; obtaining, by the server, a target synchronization sub-network to be networked, based on signal intensities of all the synchronization frames received by the base station in the out-of-step state, wherein the number of the base stations in the target synchronization sub-network, which send synchronization frames with intensities exceeding a preset threshold to be received by the base station in the out-of-step state, is the largest; allocating, by the server, a target offset for the base station in the out-of-step state based on an idle offset in the target synchronization sub-network, and allocating a superior base station for the base station in the out-of-step state based on a network topological structure in the target synchronization sub-network; and joining, by the base station in the out-of-step state, the target synchronization sub-network, based on the target offset and a synchronization frame sent by the superior base station.
The communication method of the electronic shelf label system according to claim 10, wherein allocating, by the server, a target offset for the base station in the out-of-step state based on an idle offset in the target synchronization sub-network comprises: judging, by the server, whether there is a first idle offset between a minimum offset and a maximum offset in the target synchronization sub-network, and when there is a first idle offset, allocating the first idle offset to the base station in the out-of-step state.
The communication method of the electronic shelf label system according to claim 11, wherein further comprises: when there is no first idle offset, judging whether the maximum offset is equal to the maximum capacity number minus 1; and when the maximum offset is not equal to the maximum capacity number minus 1, allocating a second idle offset obtained by adding the maximum offset with 1 to the base station in the out-of-step state.
An electronic shelf label system, comprising a server, a plurality of base stations and a plurality of electronic shelf labels; the server being configured to determine a maximum capacity number of base stations in each of synchronization sub-networks based on a predetermined signal transmission cycle and a synchronization frame transmission duration; the server being configured to construct at least one synchronization sub-network comprising the plurality of base stations, based on the maximum capacity number of base stations and a network topological structure between the base stations; the server being configured to configure an offset of each of the base stations in the corresponding synchronization sub-network based on neighboring relationships between all the base stations in each of the synchronization sub-networks, so that each of the base stations calculates synchronization frame transmission time (t11) in the predetermined signal transmission cycle based on the offset, wherein a start moment of sending a synchronization frame by a base station with an offset of i in a same synchronization sub-network is an end moment of sending a synchronization frame by a base station with an offset of i-1, and a maximum offset in the same synchronization sub-network is a sum of the number of actual base stations and M, where M is any integer; and each of the base stations being configured to calculate idle time (t12) in a synchronization channel based on the synchronization frame transmission time (t11), so that each of the base stations receives a target synchronization frame sent by a superior base station in the idle time (t12) of the synchronization channel, and each of the base stations is configured to adjust local synchronization frame transmission time (t11) thereof based on a time offset of the target synchronization frame, wherein each of the base stations has the idle time (t12) in the synchronization channel and data frame transmission time (t12) in a data channel overlap with each other.
The electronic shelf label system according to claim 13, wherein the electronic shelf label is configured to wake up in a frame listening cycle to receive a synchronization frame sent by a synchronization base station, and adjust local time based on the synchronization frame.
A computer device, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when executing the computer program, the processor implements the steps of the method according to any one of claims 1 to 12.

Description

TECHNICAL FIELD The present disclosure relates to the technical field of communications, and particularly to a communication method of an electronic shelf label system, a system, a computer device and a storage medium. BACKGROUND The electronic shelf label is an electronic display device placed on a shelf to replace the traditional paper shelf label. Each of the electronic shelf labels (ESL) is connected to a computer database of a shopping mall via a wired or wireless network, and a latest commodity price is displayed on a screen of the electronic shelf label. The electronic shelf label system is a network system including a plurality of wireless base stations. The communication network of the existing electronic shelf label system is an asynchronization network, i.e., all the WirelessAccess Points (base stations) are not synchronized with each other. Although the asynchronization network has a simple design, a low requirement for the timing devices and a low requirement for the circuit design, the communication method based on the asynchronization network has the problem of mutual interferences when a plurality of base stations need to work in parallel due to limited channel resources, which reduces the communication stability of the electronic shelf label system. A synchronous network construction method and shelf label system are known from the prior art, for example from CN114554399A, which disclose constructing at least one synchronization sub-network including a plurality of base stations based on a network topological structure between the base stations; allocating transmission/reception time slots to each base station to obtain a time slot cycle table based on the synchronization sub-network; and enabling all base stations to transmit and receive synchronization signals according to the time slot cycle table. A radio resource synchronization method and device based on networking are known from the prior art, for example from CN104735774A. A method and system for synchronizing wireless terminal and base station and wireless terminal are known from the prior art, for example from CN113395753A. An ESLS-based synchronous network construction method and apparatus are known from the prior art, for example from WO2019/237725A1. SUMMARY The present invention is defined by the independent claims. Further embodiments are set forth in the dependent claims. Any references to inventions or embodiments not falling within the scope of the independent claims are to be interpreted as examples useful for understanding the invention. Aiming at the disadvantages of the prior art, the present disclosure provides a communication method of an electronic shelf label system, a system, a computer device and a storage medium, all of which solve the problem that in the communication method of the electronic shelf label system in the prior art, a plurality of base stations interfere with each other when they are working in parallel. The present disclosure constructs at least one synchronization sub-network based on a network topological structure between the base stations and a determined maximum capacity number of base stations in each of the synchronization sub-networks, allocates synchronization frame time in a synchronization channel for each of the base stations based on an offset of each of the base stations in the corresponding synchronization sub-network, so that the synchronization frames sent by all the base stations has central and adjacent feature in time, which not only ensures that each of the base stations has its synchronization frame transmission time and data transmission time and prevents the plurality of base stations from interfering with each other when they are working in parallel, but also shortens a frame listening cycle of the electronic shelf label and reduce a power consumption thereof. In a first aspect, the present disclosure provides a communication method of an electronic shelf label system comprising a server, a plurality of base stations and a plurality of electronic shelf labels, the method including: determining, by the server, a maximum capacity number of base stations in each of synchronization sub-networks, based on a predetermined signal transmission cycle and a synchronization frame transmission duration; constructing, by the server, at least one synchronization sub-network including the plurality of base stations, based on a network topological structure between the base stations and the maximum capacity number of base stations; configuring, by the server, an offset of each of the base stations in the corresponding synchronization sub-network based on neighboring relationships between all the base stations in each of the synchronization sub-networks, so that each of the base stations calculates synchronization frame transmission time in the predetermined signal transmission cycle based on the offset, and a start moment of sending a synchronization frame by a base station with an offset