CN117241368A - Method for improving multi-concurrency processing efficiency of wireless fire alarm system - Google Patents

Abstract

The invention discloses a method for improving the multi-concurrency processing efficiency of a wireless fire alarm system, which comprises the following steps: the wireless terminal uses the low-power RTC clock to synchronize with the wireless alarm controller; the communication time slot division is carried out on the system cascade channel according to the channel configuration, and the time slot error is eliminated through the inspection period clock calibration; when concurrent uplink data occurs, the wireless terminal detecting communication conflict starts packet time slice retransmission to perform conflict processing; the wireless controller receives and responds to the concurrent uplink data; the wireless terminal performs the next communication processing according to the downlink data of the wireless controller in the concurrent processing process, and the concurrent communication process is completed; by adopting the concurrency conflict processing method of active reporting of the grouping time slices in the synchronous wireless system, the problem of low concurrency efficiency of the wireless fire alarm system terminal is solved, the reliability of multi-concurrency alarm uploading is improved, the transmission time delay is reduced, and the system has faster alarm linkage response speed and fault recovery speed.

Description

Method for improving multi-concurrency processing efficiency of wireless fire alarm system

Technical Field

The invention belongs to the technical field of fire alarm, and particularly relates to a method for improving the multi-concurrency processing efficiency of a wireless fire alarm system.

Background

The wireless fire alarm system mainly has the following functions: can timely find fire and timely alarm to the management department to ensure safety. Can timely find fire and timely alarm to the management department to improve the efficiency of fire alarm processing. Can timely find fire and timely alarm to the management department to reduce the loss caused by fire. One key factor for ensuring the timeliness of alarm processing is to solve the wireless signal concurrency conflict and improve the data transmission efficiency under the condition of multiple concurrency.

Most wireless fire alarm systems in the current fire alarm field, such as a LoRa wireless fire alarm system, an FSK fire alarm system and the like, adopt a wireless modulation mode to increase the transmission distance of signals and reduce the transmission rate of wireless data, and the wireless fire alarm system has the characteristics of: the single device occupies a physical channel for a long time, and the terminal sensor alarms randomly and concurrently. For the traditional wired system, the current running state of the terminal can be quickly obtained by using a patrol mode, but for the wireless system, in order to strictly control the power consumption of the equipment, most of the terminals are in a dormant state in actual running, namely, the condition of receiving data in real time is not provided, so that the alarm state of the terminal equipment is actively uploaded after being detected by a sensor, the channel activity is uncontrollable, and if a plurality of terminal equipment simultaneously send data, the data frames of the plurality of terminal equipment are mutually overlapped on a physical channel, so that a receiving end cannot correctly receive the data. In order to communicate efficiently, some mechanism is required to determine the usage rights of the resources.

In order to improve the concurrent processing efficiency of the wireless fire alarm system, some solutions are proposed in the published patent application. The Chinese patent with the application number of 202011639729.5 discloses a concurrent double-module gateway wireless fire alarm system and an implementation method, and the system uses double-module transmission in a mode of adding physical channels, is divided into an emergency frequency band and an idle frequency band, and solves the problem that when a certain frequency band is occupied, reported information is lost or not timely reported to a certain extent. The invention has the following defects: when a large number of concurrent alarm data transmission occurs at the terminal, the system and the method cannot efficiently solve the problem of channel blocking through double-channel processing, but the concurrent processing efficiency of the double-module is only doubled, and the problem of communication blocking caused by channel environment degradation due to the change of the external environment in the operation process of the system cannot be solved.

The invention discloses a communication method for avoiding conflict of a wireless single-channel communication network, which is disclosed in China patent with application number 202110276697.5, wherein the communication network comprises a gateway node and a plurality of terminal nodes; the gateway node communicates with the server; each terminal node is communicated with the gateway node; the gateway node and each terminal node are respectively stored with a network node numbering priority queue, the communication network is sequentially and circularly operated according to the sequence of a preparation time period, a node communication time period, a network management time period and a network idle time period, and the problem that a single-channel communication network is easy to conflict is solved to a certain extent: the method solves the problem that the storage of multiple transmission paths and the selection of an automatic optimal path in communication cannot handle real-time information transmission, increases signal transmission delay on waiting and executing of an idle time period of a communication network, and greatly increases the probability of abnormal communication caused by channel blockage of the optimal path under the condition that a large amount of concurrent data exist for terminal nodes.

Disclosure of Invention

The invention provides a method for improving the multi-concurrency processing efficiency of a wireless fire alarm system. Firstly, in order to solve the problems, the embodiment of the invention discloses a wireless fire alarm system based on a LoRa modulation technology, which comprises the following components: wireless fire alarm controller, and various wireless terminal alarm devices connected with the wireless relay and controller. The wireless terminal alarm equipment comprises a wireless smoke-sensing fire detector, a wireless temperature-sensing fire detector, a wireless input module, a wireless input/output module, a wireless audible and visual alarm, a wireless manual alarm button, a wireless fire hydrant button and other equipment, but further comprises other more equipment which is not limited in the range, and is subsequently and uniformly called as wireless terminal equipment.

The wireless controller of the system adopts a multi-channel communication mode to carry out data transmission with the wireless terminal, the communication channel comprises a patrol channel and a cascade channel, wherein the patrol channel is used as an information transmission channel for the controller to carry out patrol on the terminal, and the cascade channel is used as an information transmission channel for the terminal to actively report information. The patrol channel and the cascade channel work independently and are not affected each other.

The wireless alarm controller and the wireless terminal state packet of the system are uploaded by adopting a controller cascade channel, a system synchronous clock is provided, N terminal (N is less than or equal to 64) point positions can be supported maximally by adopting a synchronous communication mode, and each terminal point position is provided with a unique equipment serial number.

The method for improving the multi-concurrency processing efficiency of the wireless fire alarm system comprises the following steps: after the wireless controller establishes normal communication with the wireless terminal equipment, the wireless controller periodically patrols and examines the wireless terminal equipment according to the unique network serial number of the wireless terminal.

And (3) carrying out system clock synchronization on the wireless terminal equipment in each inspection period, so as to correct clock running offset errors and ensure clock synchronization of the terminal and the controller.

When a plurality of terminal devices give an alarm at the same time, the terminal uploads data according to a time slice grouping mode, and comprehensive examination rate is carried out according to data air time length and local data processing delay of the devices, so that time slot division is completed. Wherein the time slice transmission time slot is divided in a manner that considers the transmission characteristics of the wireless channel.

The aim of the invention is achieved by the following technical scheme;

step 1: the wireless terminal adopts a low-power RTC clock to synchronize an uplink communication clock with the wireless controller;

step 2: dividing communication time slots in a synchronous cascade channel, and eliminating time slot errors through calibrating a patrol period clock;

step 3: when concurrent uplink alarm data occurs, the wireless terminal detects whether communication conflict exists or not;

step 4: a wireless terminal with communication conflict starts packet time slice retransmission conflict processing;

step 5: the wireless controller carries out concurrent uplink data processing;

step 6: and the wireless terminal receives downlink response data for processing after concurrent processing.

Further, the wireless terminal performs uplink communication clock synchronization with the wireless alarm controller by adopting the low-power RTC clock, and the method comprises the following steps:

when the wireless terminal works, the wireless terminal enters a periodic dormancy awakening state, and the low-power RTC clock normally operates;

the wireless terminal uses an RTC clock as a local synchronous clock, wherein the RTC clock is a real-time clock;

and when the wireless terminal accesses the network, acquiring a time stamp Tstamp from the wireless controller, and synchronizing the Tstamp with the RTC time of the wireless terminal.

The wireless terminal divides time slices in a synchronous cascade channel;

dividing the communication time slot into a sending time slot, a receiving time slot, a sending reserved time slot and a receiving reserved time slot;

the wireless terminal sends data at the starting point of the time slot, the controller sends data at the midpoint of the time slot, namely the receiving starting point of the corresponding wireless terminal, and the wireless controller adopts cascade channel response after receiving;

further, the communication time slot division is performed on the synchronous cascade channel, and the time slot error is eliminated through the calibration of the inspection period clock, comprising:

after judging that the state information needs to be actively reported, the wireless terminal calculates a time difference T1 between the current time and the starting time of the next transmission time slice, wherein the value range of T1 is Tslot more than or equal to T1 more than or equal to 0, and Tslot is the time slot duration of a cascade channel;

when Tlot/2 is more than or equal to T1 is more than or equal to 0, the terminal skips the next time slice, and data reporting is carried out on the next time slice. When Tslot is more than or equal to T1 and more than Tslot/2, data is sent in the next time slice;

the wireless terminal sets the wake-up period of the RTC clock as Trtcduty, reads the RTC count register value when receiving the time stamp Tstamp, converts the RTC count register value into the time less than or equal to Trtcduty, and marks the time as Tcnt;

the integral count value duration of the Trtcduty is Trtcsum, and the local synchronization duration Tlocal=Trtcsum+Tcnt of the wireless terminal is obtained;

and comparing the difference value between the local synchronous time period Tlocal and the time stamp Tstamp to obtain an error time period Terr, compensating the Terr to the local synchronous time period Tlocal for clock error calibration, and carrying out periodic clock calibration on all wireless terminals in a routing inspection period by the wireless controller to complete accumulated clock error elimination.

Further, the wireless terminal determines a communication conflict, including:

when a plurality of terminal devices simultaneously transmit in the same transmission time slot, a receiving end receives a data packet of one terminal, a controller returns response data to the terminal according to the received terminal sequence number, and other terminals enter retransmission processing after comparing sequence numbers with the sequence numbers of the other terminals under the condition that the receiving time slot receives the response packet;

when the receiving end cannot receive the effective data packet and packet loss occurs, the controller cannot answer back in the receiving time slot of the terminal, and all conflict devices perform retransmission processing;

further, the wireless terminal initiates concurrent conflict processing, including:

step 4-1: determining the group number of each retransmission packet according to the terminal sequence number;

step 4-2: after detecting the conflict, carrying out retransmission control according to the packet group number;

step 4-3: ending communication after successful retransmission;

step 4-4: ending communication after exceeding the maximum retransmission times;

further, the wireless controller receiving process includes:

after receiving the status data uploaded by the terminal, the wireless controller judges whether the data is transmitted according to the time slice mode according to the signal arrival time, and if the data is judged to be transmitted according to the time slice mode, the controller responds to the terminal according to a preset response time slot. If the terminal does not send data according to the time slot, the terminal responds after a fixed delay time is carried out, wherein the delay time is the delay for ensuring the wireless terminal to switch from a sending mode to a receiving mode;

further, the wireless terminal receiving process includes:

after actively reporting data, the wireless terminal opens to receive before Tpre at the start of the receiving sub-slot of the current slot, and exits from the receiving state after overtime after reaching the maximum receiving window duration Trmax:

the wireless terminal receives the correct data packet and is ACK with the sequence number of the wireless terminal, and the terminal enters a normal inspection state;

the wireless terminal receives the correct data packet and is ACK with a non-self sequence number, and the terminal enters retransmission processing;

the wireless terminal receives the data packet of the expected data type, acquires the air time in the data packet, directly calculates the starting time of the next process according to the time stamp in the response packet, and maintains the synchronous state;

the wireless terminal receives the error data packet and performs retransmission processing according to the receiving timeout;

after the wireless terminal calculates the air time of the received data packet according to the time, the wireless terminal calculates the starting point of the next retransmission time slot according to the packet condition.

Compared with the prior art, the invention has the beneficial effects that:

1. the invention realizes the balanced processing of the concurrent conflict reporting processing time through the active reporting processing method of the grouping time slices in the synchronous wireless system, better solves the problem of low concurrent efficiency of the wireless fire alarm system terminal, improves the alarm reliability under multiple concurrencies, reduces the power consumption of the terminal, reduces the transmission delay of the system and ensures that the wireless fire alarm system has faster fault recovery speed;

2. after the wireless controller and the wireless terminal equipment establish normal communication, the wireless controller periodically patrols the wireless terminal equipment, and performs system clock synchronization on the wireless terminal equipment in each patrol period, so as to correct clock running offset errors and ensure clock synchronization of the terminal and the controller.

Drawings

In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart of a method for improving multiple concurrency processing efficiency of a wireless fire alarm system according to an embodiment of the present invention;

fig. 2 is a schematic diagram of processing a terminal time slot with a time difference Tslot/2 being greater than or equal to T1 being greater than or equal to 0, where tslot=400 ms;

fig. 3 is a schematic diagram of processing a terminal time slot with a time difference Tslot greater than or equal to T1 > Tslot/2, where tslot=400 ms;

fig. 4 is a schematic diagram of a first retransmission time slot according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a second retransmission time slot according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a third retransmission time slot according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a fourth retransmission slot according to an embodiment of the present invention;

fig. 8 is a schematic diagram of a time slot for exiting reception over time according to an embodiment of the present invention;

Detailed Description

In order to better understand the present invention, the technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the drawings in the embodiments of the present invention. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention.

In order to improve concurrency transmission efficiency, under the condition that the number of the concurrent alarm devices is unknown, the processing algorithm provided by the invention is a method for thinning grouping processing, namely, grouping is carried out sequentially according to the terminal address sequence number and the sending times, processing time delay and cost after grouping are considered, optimizing processing is carried out on grouping time slot division, namely, concurrency efficiency is considered, power consumption and transmission timeliness are also considered, and time balancing processing of concurrency conflict reporting processing is realized.

In general, the invention provides a method for improving the multi-concurrency processing efficiency of a wireless fire alarm system, which better solves the problem of low terminal concurrency efficiency of the wireless fire alarm system by actively reporting the processing method in a grouping time slice in a synchronous wireless system, improves the alarm reliability under multi-concurrency, reduces the power consumption of the terminal and the transmission delay of the system, and ensures that the wireless fire alarm system has faster fault recovery speed:

in order to illustrate the effects of the above-described aspects of the embodiments of the present invention, a description will be given below with reference to specific examples.

In a specific embodiment, the wireless terminal actively reports the time slot; the wireless terminal actively reports and adopts a cascade channel, and the wireless controller responds by adopting the cascade channel; the cascade channels have certain occupation in the normal process, such as receiving a network access synchronous request, sending a control command in a patrol stage and the like, but the channel occupation rate is smaller as a whole; considering the priority of fire alarm state, time slice division is carried out on the cascade channels to mainly report the air time of the data packet actively. The terminal actively reports the transmission time of 144ms, the receiving time of 124ms, the total length of 268ms, the reserved time slot of 132ms, the time slot Tslot of the cascade channel of 400ms, the reserved time slot of 56ms is transmitted, the reserved time slot of 76ms is received, and 190 time slices can be divided according to the 76 second inspection cycle setting.

It is specified that the wireless terminal can only transmit data at the beginning of a slot, and the controller or transceiver can only transmit data at the midpoint of the slot, i.e., the receiving beginning of the corresponding terminal, with the transmit slot and the receive slot each forming an entire slot of 200 ms. The reserved time slots are used for conversion processing between the receiving and transmitting, and error protection is formed for clocks between the time slots.

The wireless terminal and the wireless alarm controller are in clock synchronization; the system clock running in the low power consumption mode of the wireless terminal only has two system clocks, namely the low power consumption clock and the RTC clock, and the low power consumption clock of the terminal is used for inspection control, so that the RTC clock can only be used for periodic timing. Before the terminal works normally, network access and time synchronization are needed, and a time stamp is acquired from the superior equipment when the terminal requests network access, wherein the time stamp is the unique time base of the subnet. The timing of the functional part of the terminal is completed by the low-power RTC clock, and Trtcduty is set to be 500ms. After the power-on RTC clock counts time, after receiving the time stamp, the transceiver time and the local RTC time are synchronized, and the specific synchronization mode is as follows:

and when the terminal receives the time stamp, reading the RTC count register value, converting the RTC count register value into time within Trtcduty, and adding the integer count value of Trtcduty to obtain local time.

And (3) performing difference between the local time and the acquired timestamp to obtain a difference value between the local clock and the controller or transceiver clock, wherein the difference value plus the RTC current time is the network synchronization time, and the time difference value needs to be updated each time a new timestamp Tstamp is received.

And (3) waking up through the RTC, judging that state change data need to be sent, after judging that state information needs to be actively reported by the terminal, calculating a time difference T1 (Tslot=400 ms) between the current time and the starting time of the next sending time slice, wherein the value range of T1 is 400 to or more than T1 to or more than 0, and when 200 to or more than T1 to or more than 0, the terminal is set to skip the next time slice and report data in the next time slice. When the time slot is 400 more than or equal to T1 and more than 200, data is sent in the next time slot, and the terminal time slot processing is shown in fig. 2 and 3.

When a plurality of terminal devices transmit simultaneously in the same transmission time slot, communication collision can occur, and a receiving terminal can occur in two cases according to the severity of the concurrency collision. The first is that a data packet of one terminal is received, and the second is that a valid data packet is not received, and the situation of packet loss occurs.

When the first situation occurs, the controller returns response data to the terminal according to the received terminal serial number, and other terminals enter retransmission processing when the other terminals receive the response packet in the receiving time slot and the comparison serial number is not the own serial number.

When the second situation occurs, the controller does not reply back in the receiving time slot of the terminal, and all the conflict devices perform retransmission processing.

The retransmission process adopts a packet retransmission strategy, the number of full loading points of the wireless controller is 64, all the device serial numbers are divided into two groups according to parity in the first retransmission, and the delay with the odd serial number is retransmitted in the next time slot after the end of the current time slot. The next slot with even number after the end of the current slot is retransmitted as shown in fig. 4.

The first retransmission is intended to solve a few collision retransmission problems with a small delay, such as the case where the collision terminal has only 1,2 devices, and when the number is large, the retransmission process needs to be continued.

The 1 st group of devices delay 1 transmission time slot to retransmit data after the first retransmission is finished, the 2 nd group of devices delay 2 transmission retransmission data after the first retransmission is finished, the 3 rd group of devices delay 4 time slots to retransmit data after the first retransmission is finished, and the 4 th group of devices delay 4 time slots to retransmit data after the first retransmission is finished. The second retransmission time slot is shown in fig. 5 below.

The second retransmission groups the terminals into 4 groups, the grouping being as follows.

Group number	Device serial number
		n (n is an integer, n=1, 2,3, 4)	4 x m+n (m is 0-15)

The third retransmission starts to divide the parity group terminals into 4 groups of devices each, eight groups in total, and the grouping is as follows.

The third retransmission time slot is shown in fig. 6 below, and the 1 st group of devices delays retransmission of data by 0 time slots after the second retransmission is completed. Group 2 devices delay 1 slot for retransmission of data after the second retransmission is completed. Group 3 devices delay retransmitting data 3 slots after the second retransmission is completed. Group 4 devices delay retransmitting data 4 slots after the second retransmission is completed. Group 5 devices delay 6 time slots to retransmit data after the second retransmission is completed. Group 6 devices delay retransmitting data 7 slots after the second retransmission is completed. Group 7 devices delay retransmitting data 9 slots after the second retransmission is completed. Group 8 devices delay retransmitting data 10 slots after the second retransmission is completed.

The fourth retransmission is performed with the original packet sequence number unchanged, but the eighth group device delays the transmission time slot from the original maximum to the minimum, and the retransmission time delay of the first group device is adjusted from the original minimum to the maximum, and the fourth retransmission time slot is shown in fig. 7 below.

Group 1 devices delay 14 slots to retransmit data after the third retransmission is completed. Group 2 devices delay retransmitting data 12 slots after the third retransmission is completed. Group 3 devices delay 10 slots to retransmit data after the third retransmission is completed. Group 4 devices delay retransmitting data 8 slots after the third retransmission is completed. Group 5 devices delay 6 time slots to retransmit data after the second retransmission is completed. Group 6 devices delay retransmitting data 4 slots after the third retransmission is completed. The 7 th group of devices delays 2 slots for retransmitting data after the third retransmission is completed. Group 8 devices delay 0 time slot for retransmitting data after the third retransmission is completed.

The fifth to tenth retransmission packets are unchanged, and each time, the next delay adjustment is performed only according to the last packet delay so as to balance the retransmission time of all the packets, and the retransmission is carried out for 10 times in the current transmission period of each alarm event. If the single judgment time slot exceeds one clock period, the transmission time slot is adjusted to the next period.

The wireless controller receives and processes; after receiving the status data uploaded by the terminal, the wireless controller judges whether the data is transmitted according to the time slice mode according to the signal arrival time, and if the data is judged to be transmitted according to the time slice mode, the controller responds to the terminal according to a preset response time slot. If the terminal does not send data according to the time slot, the terminal responds after the fixed delay Tdelay is 16ms, and the delay 16ms is the delay for ensuring the wireless terminal to switch from the sending mode to the receiving mode.

Receiving and processing by a wireless terminal; after the wireless terminal actively reports the data, the wireless terminal opens the reception for 20ms before Tpre is the start point of the receiving sub-time slot of the current time slot, the maximum receiving window duration Trmax is 220ms, and the wireless terminal exits the receiving state after overtime, and the specific time slot is shown in fig. 8:

the terminal receives data in four cases:

the terminal receives the correct data packet and is ACK with the sequence number of the terminal;

the terminal receives the correct data packet and is ACK with a non-self sequence number;

the terminal receives the error data packet;

the terminal receives overtime;

for the first case, the terminal enters a normal patrol state.

In the second case, the terminal enters a retransmission process.

In the first two cases, the terminal receives the data packet of the expected data type, namely, the terminal can know the air time of the received data packet, the response packet contains a time stamp, and the terminal directly calculates the starting time of the next process according to the time stamp and keeps the synchronous state.

In the third case, the terminal receives the erroneous data packet, in which case the terminal may not necessarily obtain the air time of the data packet by parsing the data packet, and the next processing caused by this case is consistent with the fourth case, and the processing needs to be performed according to the reception timeout. Therefore, in case 3, it is assumed that the non-integer count value of the reception timeout timer to be read when the RXDONE interrupt is triggered is T42PermsCnt, and the reception timeout timer is T42 (PDR is 1250) and the count period is 10ms according to the present software. Let T42 be the integer portion count value of T4210msCount, the received error packet length RXPacketTime is about:

RXPacketTime＝10*T4210msCount+(T42PermsCnt％1250)*10)/1250ms

the terminal calculates the air time of the received data packet according to the time, and then calculates the starting point of the next retransmission time slot according to the packet condition.

The fourth case continues the retransmission process.

The preferred embodiments of the invention disclosed above are intended only to assist in the explanation of the invention. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise form disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best understand and utilize the invention. The invention is limited only by the claims and the full scope and equivalents thereof.

Claims (7)

1. A method for improving multiple concurrent processing efficiency of a wireless fire alarm system, comprising:

step 1: the wireless terminal adopts a low-power RTC clock to synchronize an uplink communication clock with the wireless controller;

step 2: dividing communication time slots in a synchronous cascade channel, and eliminating time slot errors between a wireless terminal and a wireless controller through calibrating a patrol period clock;

step 3: when concurrent uplink alarm data occurs, the wireless terminal detects whether communication conflict exists or not;

step 4: a wireless terminal with communication conflict starts packet time slice retransmission conflict processing;

step 5: the wireless controller carries out concurrent uplink data processing;

step 6: and the wireless terminal receives downlink response data for processing after concurrent processing.

2. The method for improving multiple concurrency processing efficiency of a wireless fire alarm system according to claim 1, wherein the wireless terminal uses a low power RTC clock to synchronize an uplink communication clock with the wireless alarm controller, comprising:

when the wireless terminal works, the wireless terminal enters a periodic dormancy awakening state, and the low-power RTC clock normally operates;

the wireless terminal uses an RTC clock as a local synchronous clock, wherein the RTC clock is a real-time clock;

and when the wireless terminal accesses the network, acquiring a time stamp Tstamp from the wireless controller, and synchronizing the Tstamp with the RTC time of the wireless terminal.

3. The method for improving multiple concurrency processing efficiency of a wireless fire alarm system according to claim 2, wherein the communication time slots are divided in a synchronous cascade channel, and the time slot errors are eliminated by calibrating a patrol cycle clock, comprising:

after judging that the state information needs to be actively reported, the wireless terminal calculates a time difference T1 between the current time and the starting time of the next transmission time slice, wherein the value range of T1 is Tslot more than or equal to T1 more than or equal to 0, and Tslot is the time slot duration of a cascade channel;

when Tslow/2 is more than or equal to T1 and more than or equal to 0, the terminal skips the next time slice, and performs data reporting on the next time slice; when Tslot is more than or equal to T1 and more than Tslot/2, data is sent in the next time slice;

the wireless terminal sets the wake-up period of the RTC clock as Trtcduty, reads the RTC count register value when receiving the time stamp Tstamp, converts the RTC count register value into the time less than or equal to Trtcduty, and marks the time as Tcnt;

the integral count value duration of the Trtcduty is Trtcsum, and the local synchronization duration Tlocal=Trtcsum+Tcnt of the wireless terminal is obtained;

and comparing the difference value between the local synchronous time period Tlocal and the time stamp Tstamp to obtain an error time period Terr, compensating the Terr to the local synchronous time period Tlocal for clock error calibration, and carrying out periodic clock calibration on all wireless terminals in a routing inspection period by the wireless controller to complete accumulated clock error elimination.

4. The method for improving multiple concurrency processing efficiency of a wireless fire alarm system according to claim 1, wherein the wireless terminal determines a communication conflict, comprising:

when a plurality of wireless terminal devices simultaneously transmit in the same transmission time slot, a receiving end receives a data packet of one wireless terminal, a controller returns response data to the wireless terminal according to the received wireless terminal sequence number, and other wireless terminals enter retransmission processing when the comparison sequence number is not the own sequence number under the condition that the receiving time slot receives the response packet;

when the receiving end cannot receive the effective data packet and packet loss occurs, the controller cannot answer back in the receiving time slot of the wireless terminal, and all conflict devices perform retransmission processing.

5. The method for improving multiple concurrency processing efficiency of a wireless fire alarm system of claim 1, wherein the wireless terminal initiates concurrency collision handling comprising:

step 4-1: determining the group number of each retransmission packet according to the serial number of the wireless terminal;

step 4-2: after detecting the conflict, carrying out retransmission control according to the packet group number;

step 4-3: ending communication after successful retransmission;

step 4-4: and ending the communication after the maximum retransmission times are exceeded.

6. The method for improving multiple concurrency processing efficiency of a wireless fire alarm system of claim 1, wherein the wireless controller receives the processing comprising:

after receiving the status data uploaded by the wireless terminal, the wireless controller judges whether the data is transmitted according to the time slice mode according to the signal arrival time, and if the data is judged to be transmitted according to the time slice mode, the controller responds to the wireless terminal according to a preset response time slot;

if the wireless terminal does not send data according to the time slot, the wireless terminal responds after carrying out fixed delay Tdelay, wherein the delay Tdelay is larger than the conversion time required by the wireless terminal in the process of switching from the sending mode to the receiving mode.

7. The method for improving multiple concurrency processing efficiency of a wireless fire alarm system according to claim 1, wherein the wireless terminal receiving process comprises:

after actively reporting data, the wireless terminal opens to receive at a time Tpre before the start of a receiving sub-time slot of the current time slot, and exits from a receiving state after overtime after reaching the maximum receiving window duration Trmax:

the wireless terminal receives the correct data packet and is ACK with the sequence number of the wireless terminal, and the wireless terminal enters a normal inspection state;

the wireless terminal receives the correct data packet and is ACK with a non-self sequence number, and the wireless terminal enters retransmission processing;

the wireless terminal receives a data packet of a desired data type and acquires a time stamp therein, and directly calculates the starting time of the next process according to the time stamp Tstamp in the response packet and maintains a synchronous state;

the wireless terminal receives the error data packet and performs retransmission processing according to the receiving timeout;

after the wireless terminal calculates the air time of the received data packet according to the time, the wireless terminal calculates the starting point of the next retransmission time slot according to the packet condition.