Ad hoc network wireless intercom system and method for old cell reconstruction

Abstract

The invention discloses an ad hoc network wireless intercom system and method for old cell reconstruction, the system is composed of an outdoor wireless digital host, a wireless repeater and a wireless indoor extension, an ad hoc multi-hop wireless local area network is constructed based on an ESP-WIFI-MESH protocol, redundant communication is realized by adopting a mesh topology structure, and the wireless intercom system and the wireless repeater are used for wireless intercom. The problems of high wiring cost and poor wireless signal coverage in the prior art are solved. The talkback method comprises the following steps: marking an alarm instruction as the highest level through a priority transmission mechanism, and preempting a channel to ensure zero delay of an emergency signal; voice and video data are scheduled in a hierarchical manner, and real-time performance and bandwidth are balanced. The wireless repeaters dynamically allocate IP addresses, support plug and play of extension sets, and realize cross-building communication and remote management in combination with a local area network of a community.

Description

Technical Field

[0001] The present invention relates to the field of intercom technology, and particularly to a self-organizing wireless intercom system and method for the renovation of old residential areas. Background Art

[0002] Traditional building intercom systems mostly rely on wired cabling or ordinary wireless technologies (such as Wi-Fi, Bluetooth). Wired systems have high construction costs and are difficult to renovate in old residential areas; ordinary wireless technologies have problems such as small coverage, weak wall penetration ability, and susceptibility to interference. In the prior art, Mesh network-based solutions (such as ZigBee) are difficult to support high-definition audio and video transmission due to insufficient bandwidth, and have relatively high maintenance costs.

[0003] For example, Chinese Patent CN108924492A discloses a smart visual access control system based on Wi-Fi networking, but it relies on a third-party cloud server and has data security risks; wireless signals are easily affected by building structures and electromagnetic interference, resulting in unstable communication. In addition, the method of using a cloud management server usually requires paying fees to the corresponding third-party operator, and due to third-party management, it is easy to have information leakage.

[0004] Chinese Patent Publication No. CN205921681U discloses an upgraded architecture of an old residential building intercom system based on wireless technology. Its unit entrance machine is connected to a signal conversion device by wire; the wireless signal repeater is wirelessly connected to the signal conversion device; a small wireless local area network is formed among the signal conversion device, the wireless signal repeater, and the indoor wireless intercom terminal, and is combined with the unit entrance machine and the indoor machine to form a new networking method. This networking method can enable the indoor machines without faults to communicate according to the traditional wired intercom method; while the faulty indoor machines communicate wirelessly (that is, replacing these faulty indoor machines with indoor machines supporting wireless communication, and those without faults do not need to be replaced), so as to utilize the original system resources for improvement on the basis of the original system and restore the intercom function. In the above intercom system, when there are large-scale equipment failures, the extension machines need to be manually replaced, lacking flexibility. In addition, traditional Wi-Fi networking uses a star topology, and a single point of failure is likely to cause the network to collapse, and dense Wi-Fi devices are likely to cause channel competition, affecting communication stability.

[0005] Therefore, there is an urgent need for a wireless intercom system that supports self-organizing networking, high scalability, and low cost to meet the renovation requirements of old residential areas. Summary of the Invention

[0006] The present invention overcomes the above-mentioned deficiencies in the technology and provides a configuration method and a control method for intelligent devices.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] In the first aspect of the embodiment of the present invention, a self-organizing network wireless intercom system for the renovation of old residential areas is disclosed, including:

[0009] Multiple outdoor wireless digital hosts 100, each including a first ESP wireless module 101, a first Wi-Fi module 102, and a main control CPU module 103; the first ESP wireless module 101 and the first Wi-Fi module 102 are respectively interconnected with the main control CPU module 103;

[0010] Multiple wireless repeaters 200, each including a second ESP wireless module 201 and a second Wi-Fi module 202;

[0011] Multiple wireless indoor extension phones 300, each including a third ESP wireless module 301;

[0012] The first ESP wireless module 101, the second ESP wireless module 201, and the third ESP wireless module 301 are all wireless communication modules supporting the Mesh protocol; the outdoor wireless digital hosts 100, the multiple wireless repeaters 200, and the multiple wireless indoor extension phones 300 are wirelessly connected through their respective ESP wireless modules and self-organize into a wireless local area network;

[0013] The outdoor wireless digital hosts 100 of different buildings communicate with each other through the local area network of the community.

[0014] Preferably, each outdoor wireless digital host 100 further includes: a memory 104, a first audio input module 105, a first audio output module 106, a Flash memory 107, a first digital-to-analog and analog-to-digital conversion module 108, a lock control module 109, a liquid crystal display screen 110, a numeric keypad 111, and a first power supply module 112 for powering each module of the outdoor wireless digital host 100. The main control CPU module 103 is also respectively interconnected with the memory 104, the Flash memory 107, the first digital-to-analog and analog-to-digital conversion module 108, the lock control module 109, the liquid crystal display screen 110, and the numeric keypad 111; the first ESP wireless module 101 sends voice signal data packets to the wireless indoor extension phones 300 or receives intercom signals from the wireless indoor extension phones 300 through multiple wireless repeaters 200;

[0015] The first digital-to-analog and analog-to-digital conversion module 108 is respectively electrically connected to the first audio input module 105 and the first audio output module 106; the lock control module 109 is used to receive the unlocking instruction sent by the main control CPU module 103 for unlocking and locking;

[0016] Each wireless indoor extension 300 further includes: a second audio input module 302, a second audio output module 303, a second digital-to-analog and analog-to-digital conversion module 304, a button module 305, and a third power supply module 306 for powering each module of the wireless indoor extension 300; the second ESP wireless module 301 sends an intercom signal to the outdoor wireless digital host 100 or receives a voice signal data packet from the wireless indoor extension 300 through a plurality of wireless repeaters 200.

[0017] The second digital-to-analog and analog-to-digital conversion module 304 is electrically connected to the second audio input module 302 and the second audio output module 303 respectively.

[0018] Preferably, it further includes: a community integrated management platform 400, which is set in the property center and used to monitor the community status.

[0019] Each outdoor wireless digital host 100 communicates with the community integrated management platform 400 through the community local area network.

[0020] Each outdoor wireless digital host 100 further includes a first alarm module 113, an Ethernet communication module 114, a camera module 115, a face recognition module 116, an NFC module 117, and a fingerprint recognition module 118 that are respectively interconnected with the main control CPU module 103.

[0021] The first alarm module 113 includes a first alarm button 1131. When it is detected that the first alarm button 1131 is continuously pressed for more than a preset second threshold, an alarm instruction is triggered; the alarm instruction is sent to the community local area network through the Ethernet communication module 114 or the first WiFi module 102, and then forwarded to the community integrated management platform 400.

[0022] Each wireless indoor extension 300 further includes a second alarm module 307. The second alarm module 307 includes a second alarm button 3071. When it is detected that the second alarm button 3071 is continuously pressed for more than a preset second threshold, an alarm instruction is triggered; the alarm instruction is sent to the outdoor wireless digital host 100 through the self-organized wireless local area network of the third ESP wireless module 301, and then forwarded to the community integrated management platform 400 by the outdoor wireless digital host 100 through the community local area network.

[0023] Preferably, the community integrated management platform 400 includes:

[0024] An access control management unit 401, which is used to store the face feature templates, mobile phone numbers, unlocking passwords, and original access card information of the residents.

[0025] A remote unlocking unit 402, which is used to remotely send an unlocking instruction to the outdoor wireless digital host 100.

[0026] The emergency alarm processing unit 403 is used to receive the alarm instruction sent by the outdoor wireless digital host 100 in real time and issue an alarm, and to obtain the target position where the alarm is located by the alarm instruction and control the camera image in the area where the target position is located in the monitoring display screen to be enlarged and displayed;

[0027] The abnormal capture unit 404 is used to receive the visitor capture pictures taken by the camera module 115, and is configured to: identify whether it is the face of a registered person through the lightweight YOLO algorithm, and if it is determined to be a non-registered person, issue an alarm to remind the property personnel.

[0028] Preferably, each wireless repeater 200 further includes: a dynamic IP connection module 203 responsible for dynamic allocation of IP addresses, and a second power supply module 204 for powering each module of the wireless repeater 200;

[0029] Among them, the dynamic IP connection module 203 includes:

[0030] A processor chip 2031 that supports the DHCP protocol, which is connected to the second ESP module 201 and is used to start the DHCP protocol when detecting that a new wireless indoor extension 300 is accessed;

[0031] An IP address memory 2032, which is connected to the processor chip 2031 and is used to store the IP address pool that can be allocated;

[0032] A network interface controller 2033, which is used to communicate with the upper-level node through Ethernet.

[0033] Preferably, the first Wi-Fi module 102 uses a Wi-Fi chip that supports dual-band communication of 2.4 GHz and 5 GHz; the outdoor wireless digital host 100 further includes:

[0034] An environment adaptation module 119 connected to the main control CPU module 103, and the environment adaptation module 119 includes:

[0035] A temperature and humidity sensor 1191, which is used to monitor the environmental temperature and humidity in real time;

[0036] An air pressure sensor 1192, which is used to detect rainfall or air pressure changes;

[0037] An ambient light sensor 1193, which is used to sense the ambient light intensity;

[0038] The first Wi-Fi module 102 dynamically adjusts its own transmission power through a power dynamic adjustment mechanism;

[0039] Among them, the dynamic adjustment mechanism includes:

[0040] When the temperature detected by the temperature and humidity sensor 1191 is higher than the preset temperature, it is determined that the device is in a high-temperature environment, and it automatically switches to the 5GHz band and increases the transmission power to compensate for the high-temperature signal attenuation;

[0041] When rainfall is detected by the barometric pressure sensor 1192, it automatically switches to the 2.4GHz band and increases the transmission power to compensate for the rain attenuation effect;

[0042] When no human activity is detected by the ambient light sensor 1193, it switches to the sleep mode.

[0043] A second aspect of the embodiments of the present invention discloses an ad-hoc wireless intercom method for the renovation of old residential areas, which is characterized in that it is applied to the ad-hoc wireless intercom system described in the first aspect, and it includes the following steps:

[0044] When a user presses the alarm button of the outdoor wireless digital host or the alarm button of the wireless indoor extension, an alarm instruction is generated and encrypted into an alarm packet, a priority marking instruction is triggered, and the alarm packet is marked as the first priority, and the first priority is the highest priority;

[0045] When a visitor initiates a call through the outdoor wireless digital host, voice data of the intercom call signal is generated and encapsulated into a voice data packet, a priority marking instruction is triggered, and the voice data packet is marked as the second priority; if the outdoor wireless digital host is equipped with a camera, video stream data is synchronously generated and encapsulated into a video data packet, and a priority marking instruction is triggered to mark the video data packet as the third priority;

[0046] When a user presses the intercom button of the wireless indoor extension, voice data and video stream data of the intercom call signal are generated, respectively encapsulated into a voice data packet and a video data packet, a priority marking instruction is triggered, the voice data packet is marked as the second priority, and the video data packet is marked as the third priority;

[0047] Multiple wireless repeaters are used to perform multi-hop transmission on the alarm packet, voice data packet, and video data packet. During the transmission process, dynamic scheduling is performed according to the priority level to ensure that the first-priority data is transmitted first;

[0048] The target wireless indoor extension receives the voice data packet and the video data packet at one time and decodes them. If the decoding is successful, it triggers a ring and displays a picture, and the resident can perform voice-visual intercom or remote unlocking operation through the extension;

[0049] The ad-hoc wireless intercom system processes data transmission in the order of the first priority, the second priority, and the third priority, where the alarm packet preempts the voice and video data channels, and the voice data packet is transmitted prior to the video data packet.

[0050] Preferably, in the alarm packet data transmission path, the alarm packet is encapsulated using the AES encryption algorithm, marked in the packet header with the highest transmission priority higher than that of voice data packets, and the highest-level transmission mechanism is implemented through the self-formed wireless local area network to ensure its priority in obtaining channel resources;

[0051] In the voice packet data transmission path, the UDP protocol is used to transmit voice data packets, and the dynamic routing optimization algorithm is combined to monitor the network topology in real time to avoid the optimal path of high-load nodes or interference areas;

[0052] In the video packet data transmission path, the video data is compressed by H.265 encoding and the low-latency mode is configured.

[0053] Preferably, the highest-level transmission mechanism includes:

[0054] When an alarm packet is detected, the current non-emergency data transmission is immediately interrupted, and dedicated channel resources are reserved to ensure real-time performance;

[0055] Select the path with the highest score as the transmission path according to the first transmission path scoring formula;

[0056] The CSMA / CA algorithm is adopted, and the backoff window of the alarm packet is fixed at 2 time slots;

[0057] Among them, the first transmission path scoring formula is:

[0058] The first path score = RSS I × M + (1 / number of hops) × N; where, RSS I represents the signal strength, M represents the weight ratio of the influence of RSS I, and N represents the weight ratio of the influence of the number of hops;

[0059] Among them, 0.4 ≤ M ≤ 0.8, 0.2 ≤ N ≤ 0.6, and M + N = 1 is satisfied.

[0060] Preferably, the implementation steps of the dynamic routing optimization algorithm include:

[0061] Collect the RSS I, packet loss rate, and delay time of each path in real time;

[0062] Select the path with the highest score as the transmission path according to the second transmission path scoring formula;

[0063] Among them, the second transmission path scoring formula is:

[0064] The second path score = A1 × RSS I + A2 × (1 / delay time) + A3 × (1 - packet loss rate), where, RSS I represents the signal strength, A1 represents the weight ratio of the influence of RSS I, A2 represents the weight ratio of the influence of delay data, A3 represents the weight ratio of the influence of packet loss rate, A1 + A2 + A3 = 1, A1 > A2 > A3;

[0065] The path switching mechanism is set. If the current path score drops below the preset threshold value B, and the backup path score is higher than the preset ratio value C, the path is switched within the preset time T, where B is 15-30%, C is 20-30%, and T is 5-15ms.

[0066] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0067] 1. This case uses ESP wireless modules to build a wireless LAN based on the ESP-WIFI-MESH protocol, and adopts a mesh topology to achieve multi-hop transmission paths and form a redundant network. Even if a single node signal is attenuated or fails, the system can automatically select other nodes with strong signals to relay communication, ensuring that global communication is not interrupted, significantly improving network reliability, and especially adapting to the signal shielding problem caused by the complex building structure of old communities. By integrating only ESP modules in the wireless indoor extension and omitting the Wi Fi module, it is easy to reduce hardware costs, while avoiding the high standby power consumption of the extension due to the WiFi module, significantly reducing long-term operating energy consumption; and it will not compete with the channels of other indoor WiFi devices, ensuring communication stability. The core intercom function is guaranteed by a dedicated MESH network, and the extended functions are concentrated in the host and wireless repeater, which on the one hand avoids the direct exposure of the extension to the public network, and on the other hand avoids the high cost and high power consumption defects of the full Wi Fi solution. In addition, the Wi Fi modules of the host and wireless repeater can access the external network, support firewalls and data encryption, and realize remote management and cloud platform docking, taking into account both security and flexibility. MESH network supports multi-level relay expansion, and new extensions can automatically connect to the nearest relay node and complete the networking without complex configuration. In addition, the integrated management platform of the same community centrally monitors all host devices through the local LAN, supports remote troubleshooting, configuration updates and status analysis; and can be combined with the existing monitoring network deployment of the property to avoid duplicate wiring, reduce operation and maintenance costs, and improve management efficiency; the system can seamlessly access the existing LAN of the community, use existing network line resources, reduce network reconstruction investment in the renovation of old communities, and accelerate project implementation.

[0068] 2. The outdoor wireless digital host in this case adopts the first alarm module and the second alarm module of the wireless indoor extension to form "indoor + outdoor" dual emergency trigger coverage. The indoor extension alarm command is sent to the outdoor host via the Mesh network, and then uploaded to the management platform via Ethernet / WiFi; the outdoor host alarm is sent directly via Ethernet / WiFi, so as to ensure that even if a single node fails through the redundant path of the Mesh network, the alarm signal can still be relayed to the management platform in multiple hops, thereby improving the reliability of alarm signal transmission. The outdoor host integrates camera, face / fingerprint / NFC recognition modules, and not only integrates multi-functional access control, but also can start camera monitoring and identity verification when the alarm is triggered, providing visual on-site information for the management platform.

[0069] 3. The access control management unit in this case integrates face, mobile phone, password and traditional access control card information to form a multi-factor identity authentication system, taking into account convenience and security. The remote unlocking unit supports remote authorization unlocking by property or residents, which is especially suitable for visitor management scenarios to enhance user experience. The abnormal capture unit achieves triple optimization through the lightweight YOLO algorithm to improve the effect of captured photos. At the same time, in conjunction with behavioral analysis linkage, if a stranger is detected to be wandering for more than 3 minutes, an alarm is automatically triggered and pushed to the property to provide a basis for abnormal judgment; after the camera module captures the image through YOLO analysis, the feature vector is compared with the access control database, and the emergency unit is triggered after the stranger is determined to be a stranger, forming an efficient collaboration. Through the setting of the emergency alarm unit, it is convenient to quickly lock the incident area after receiving the alarm command, and automatically enlarge the camera image of the target area on the monitoring display screen to assist security personnel in making decisions. In this way, a highly reliable security management solution is provided for old communities that use the intercom system in this case.

[0070] 4. This case uses an environmental adaptive module to integrate three types of sensors: temperature and humidity, air pressure, and ambient light, to achieve real-time monitoring of key environmental factors such as high temperature, rainfall, and light intensity. Through a dynamic adjustment mechanism, it is easy to automatically switch between the 2.4GHz and 5GHz frequency bands according to environmental parameters to balance signal penetration and bandwidth requirements; when the temperature exceeds the preset threshold, the system automatically switches to the 5GHz frequency band and increases the transmission power to effectively offset the signal attenuation caused by high temperature; and when it rains, the air pressure sensor is linked to adjust, switch to the 5GHz frequency band and increase the power to compensate for the scattering and absorption effects of rainwater, and ensure the stability of the communication link. When the ambient light sensor detects no activity, the device enters sleep mode, retaining only the heartbeat packet monitoring function to reduce power consumption.

[0071] 5. The intercom method in this case marks the alarm command as the first priority, which can seize the voice / video channel and ensure the undelayed transmission of emergency signals, so that in the event of an emergency, the alarm data can be preferentially delivered to the property or resident terminal through multi-hop relays, shortening the response time. In addition, the alarm package is encrypted to prevent information leakage and enhance the privacy protection capabilities of the weak links in the security of old residential communities. At the same time, this case prioritizes voice (second priority) over video (third priority), balancing real-time interaction needs and bandwidth resources, so that when a visitor calls, the voice can be connected immediately and the video stream can be transmitted later to avoid network congestion. In this way, the system dynamically schedules the transmission order according to the priority, ensuring the stable transmission of key data (such as alarms and voice) in the old residential environment with limited bandwidth, thereby improving communication efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for use in the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0073] Figure 1 is a schematic diagram of the architecture of the ad-hoc wireless intercom system in this case.

[0074] Figure 2 is a block diagram of the structure of a single outdoor wireless digital host in this case.

[0075] Figure 3 is a block diagram of the structure of a single wireless repeater in this case.

[0076] Figure 4 is a block diagram of the structure of a single wireless indoor extension in this case.

[0077] Figure 5 is a block diagram of the structure of the community integrated management platform. Specific Embodiments

[0078] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0079] It should be noted that the terms "first", "second", "third", "fourth", etc. in the specification and claims of the present invention are used to distinguish different objects, rather than to describe a specific order. The terms "including" and "having" in the embodiments of the present invention and any of their variations are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0080] Embodiment 1

[0081] As Figures 1 - 5As shown, a self-organizing network wireless intercom system and method for the renovation of old residential areas includes: an outdoor wireless digital host 100, multiple wireless repeaters 200, and multiple wireless indoor extensions 300. The three are wirelessly connected through their respective ESP wireless modules and self-organize into a wireless local area network. The first ESP wireless module 101, the second ESP wireless module 201, and the third ESP wireless module 301 are all wireless communication modules that support the Mesh protocol; the outdoor wireless digital host 100, multiple wireless repeaters 200, and multiple wireless indoor extensions 300 are wirelessly connected through their respective ESP wireless modules and self-organize into a wireless local area network based on the ESP-WIFI-MESH protocol;

[0082] The outdoor wireless digital hosts 100 of different buildings communicate with each other through the local area network of the community. The local area network of the community can be the local area network of the existing monitoring system in the community or the existing local area network of the community.

[0083] As Figure 2 As shown, the outdoor wireless host 100 is fixedly installed outside the door frame of the building unit entrance. It integrates a first ESP wireless module 101, a first Wi-Fi module 102, a main control CPU module 103, a memory 104, a first audio input module 105, a first audio output module 106, a Flash memory 107, a first digital-to-analog and analog-to-digital conversion module 108, a lock control module 109, a liquid crystal display screen 110, a numeric keypad 111, and a first power supply module 112 for powering each module of the outdoor wireless digital host 100. The memory 104 is connected to the main control CPU module 101 through a DDR4 interface for caching audio and video data; the Flash memory 107 is connected to the main control CPU module 103 through an eMMC bus for storing firmware programs; the first audio input module 105 is used to input voice signals, specifically including through an audio input interface and a microphone; the first audio output module 106 is used to output voice signals, specifically including through an audio output interface and a speaker; the first digital-to-analog and analog-to-digital conversion module 108 is respectively connected to the first audio input module 105 and the first audio output module 106 for converting analog voice signals and digital signals; the lock control module 109 is connected to the main control CPU module 103 through a relay inside it for receiving an unlocking instruction and controlling the on / off of the electromagnetic lock. The liquid crystal display screen 110 and the numeric keypad 111 are respectively connected to the main control CPU module 103 to facilitate users to view and operate the buttons for intercom. Specifically, in implementation, the first ESP wireless module 101 sends voice signal data packets to the wireless indoor extension 300 or receives intercom signals from the wireless indoor extension 300 through multiple wireless repeaters 200.

[0084] Multiple wireless repeaters 200 are fixed on the wall of the corridor well, and one wireless repeater 200 is set every three floors. Each wireless repeater 200 includes:

[0085] The second ESP wireless module 201: Supports the ESP-WIFI-MESH protocol and is responsible for Mesh network communication.

[0086] The second Wi-Fi module 202: Used to connect to the Internet, can be directly connected to existing Wi-Fi devices such as mobile phones and tablets as an extended function to provide flexible access for the user side, and can also be connected to an external cloud platform or monitoring device. At the same time, the second Wi-Fi module 202 can be uniformly connected to the external network with the first Wi-Fi module 103, which is convenient for implementing security measures such as firewalls and data encryption to avoid the risk of the extension being directly exposed to the public network.

[0087] Each wireless indoor extension 300 includes:

[0088] The third ESP wireless module 301, the second audio input module 302, the second audio output module 303, the second digital-to-analog and analog-to-digital conversion module 304, the button module 305, and the third power supply module 306 that supplies power to each module of the wireless indoor extension 300; the third ESP wireless module 301 receives the voice signal data packet from the outdoor wireless digital host 100 through the wireless repeater 200 or sends an intercom signal to the outdoor wireless digital host 100 through the wireless repeater 200;

[0089] The second digital-to-analog and analog-to-digital conversion module 304 is electrically connected to the second audio output module 303 to play the voice of the digitally converted voice signal through the speaker (such as a horn) of the second audio output module 303; the second digital-to-analog and analog-to-digital conversion module 304 is also electrically connected to the second audio input module 302 to perform analog-to-digital conversion on the intercom audio signal received from the microphone of the second audio input module 302 and send it to the outdoor wireless digital host 100. In specific implementation, the ESP wireless module can also be called the ESP module; each ESP wireless module can also use chips of the ESP32 series launched by Espressif Systems that support MESH networking, such as ESP32-S2 or ESP32-C6.

[0090] The first Wi-Fi module 102 uses an Internet of Things chip that supports dual-band communication of 2.4 GHz and 5 GHz; specifically, the QCA4024 chip of the Qualcomm QCA402x series is preferably used. In this way, by supporting dual-band communication of 2.4 GHz and 5 GHz, the 2.4 GHz has strong penetration and is suitable for environments with many obstacles, while the 5 GHz has less interference and high bandwidth, which is suitable for high-quality data transmission. And this case is targeted at old residential areas, where there may be more physical obstacles. The dual-band can provide a more flexible connection method, and the device can automatically select the optimal frequency band according to the signal strength and interference situation, enhancing signal penetration and balancing speed and stability.

[0091] As Figure 1 shown, the intercom system in this case further includes: a community integrated management platform 400, which is used to monitor the community status; each outdoor wireless digital host 100 communicates with the community integrated management platform 400 through the local area network of the community. The community integrated management platform 400 is deployed in the computer room of the property management center and is connected to each outdoor wireless digital host 100 of each building through a gigabit Ethernet switch.

[0092] As described above, in this case, a wireless local area network based on the ESP-WIFI-MESH protocol is constructed through an ESP wireless module, and a multi-hop transmission path is implemented using a mesh topology to form a redundant network. Even if the signal of a single node attenuates or fails, the system can automatically select other nodes with strong signals for relay communication, ensuring that global communication is not interrupted, significantly improving the network reliability, especially adapting to the signal occlusion problem caused by the complex building structure in old communities (such as being applicable to old multi-story brick-concrete structure communities with severe signal occlusion). Moreover, the wireless indoor extension only integrates the ESP module and omits the Wi-Fi module, so as to reduce the hardware cost (the cost of the Wi-Fi chip is 2-3 times that of the ESP module), and at the same time avoid the high standby power consumption generated by the extension due to the Wi-Fi module (the standby power consumption of the Wi-Fi module is 50-100 mW, and the ESP module is only 10 μW in sleep mode), significantly reducing the long-term operating energy consumption; and there will be no situation of channel competition with the remaining Wi-Fi devices in the room, ensuring communication stability. The core intercom function is guaranteed through a dedicated MESH network, and the extended functions (such as Internet access) are concentrated on the host and the wireless repeater. On the one hand, it avoids the direct exposure of the extension to the public network, and on the other hand, it avoids the high cost and high power consumption defects of the all-Wi-Fi solution. Moreover, the Wi-Fi modules of the host and the wireless repeater can access the external network, support firewalls and data encryption, and realize remote management (such as firmware upgrade, status monitoring) and docking with the cloud platform, taking into account both security and flexibility. The MESH network supports multi-level relay expansion, and the newly added extension can automatically access the nearest relay node and complete networking without complex configuration. Combining the design of deploying wireless repeaters every three floors in the corridor not only adapts to the scattered building structure in old communities but also supports the future expansion of the number of extensions, solving the pain point of the poor scalability of traditional wiring systems. In addition, the same community integrated management platform centrally monitors all host devices through the local area network, supports remote fault troubleshooting, configuration update and status analysis; and can be deployed in combination with the existing property monitoring network, avoiding repeated wiring, reducing the operation and maintenance cost, and improving the management efficiency; thus, the system can seamlessly access the existing local area network in the community (such as the monitoring network), utilize the existing network line resources, reduce the network reconstruction investment in the renovation of old communities, and accelerate the project implementation.

[0093] As Figure 2 shown, each outdoor wireless digital host 100 further includes a first alarm module 113, an Ethernet communication module 114, a camera module 115, a face recognition module 116, an NFC module 117, and a fingerprint recognition module 118, which are respectively connected to the main control CPU module 103 in an interactive manner. The RJ45 interface of the Ethernet communication module 114 of each outdoor wireless digital host 100 is connected to the existing local area network in the community through a network cable.

[0094] The first alarm module 113 of the outdoor wireless digital host 100 includes:

[0095] The first alarm button 1131. When an emergency occurs: the user long-presses the first alarm button 1131 for 1.5 seconds to trigger an alarm instruction, and the alarm instruction is sent to the local area network of the community through the Ethernet communication module 114 or the first Wi-Fi module 102, and then forwarded to the community integrated management platform 400; generally, the Ethernet communication module 114 is used for wired connection with the local area network, but when the wired connection fails, the first Wi-Fi module 102 can also be used for wireless transmission.

[0096] As Figure 2 shown, each wireless indoor extension 300 further includes a second alarm module 307. The second alarm module 307 includes a second alarm button 3071. The second alarm button 3071 can be a button or a pull cord switch. When it is detected that the second alarm button 3071 is continuously pressed or the pull cord is triggered for 2 seconds, an alarm instruction is triggered; the alarm instruction is sent to the outdoor wireless digital host 100 through the self-organizing wireless local area network of the third ESP wireless module 301, and then the outdoor wireless digital host 100 forwards it to the community integrated management platform 400 through the local area network of the community.

[0097] As Figure 2 shown, each outdoor wireless digital host 100 further includes a first alarm module 113, an Ethernet communication module 114, a camera module 115, a face recognition module 116, an NFC module 117, and a fingerprint recognition module 118 that are respectively interconnected with the main control CPU module 103; the camera module can be used to capture images and videos for real-time monitoring and recording. The face recognition module can be used to identify the identities of residents or visitors to improve security. The NFC module can be used for access control to achieve fast access control, so as to cooperate with the face recognition module to achieve face recognition and enhanced authentication of the NFC module.

[0098] The first alarm module 113 includes a first alarm button 1131. When it is detected that the first alarm button 1131 is continuously pressed for 1.5 seconds, an alarm instruction is triggered and transmitted to the main control CPU module and sent to the local area network of the community through the Ethernet communication module 114 or the first Wi-Fi module 102, and then forwarded to the community integrated management platform 400;

[0099] Each wireless indoor extension 300 also includes a second alarm module 307, which includes a second alarm button 3071. When it is detected that the second alarm button 3071 is continuously pressed or the pull-cord switch is triggered for 2 seconds, an alarm instruction is triggered; the alarm instruction is sent to the outdoor wireless digital host 100 through the self-organized wireless local area network of the third ESP wireless module 301, and then forwarded by the outdoor wireless digital host 100 to the community integrated management platform 400 through the local local area network of the community, such as the local area line of the monitoring network. In this way, the local area line of the existing monitoring network of the community is reused to avoid adding new communication pipelines. In specific implementation, the pull-cord switch adopts a length of 1.5m to cover the reach of wheelchair users.

[0100] As mentioned above, the outdoor wireless digital host in this case uses the first alarm module and the second alarm module of the wireless indoor extension to form "indoor + outdoor" dual emergency trigger coverage. The indoor extension alarm command is sent to the outdoor host via the Mesh network, and then uploaded to the management platform via Ethernet / WiFi; the outdoor host alarm is sent directly via Ethernet / WiFi, so as to ensure that even if a single node fails through the redundant path of the Mesh network, the alarm signal can still be relayed to the management platform in multiple hops, thereby improving the reliability of alarm signal transmission. The outdoor host integrates camera, face / fingerprint / NFC recognition modules, and not only integrates multi-functional access control, but also can start camera monitoring and identity authentication when the alarm is triggered, providing visual on-site information for the management platform.

[0101] like Figure 5 As shown, the community integrated management platform 400 includes:

[0102] Access control management unit 401, used to store resident facial feature templates, mobile phone numbers, unlocking passwords and original access control card information;

[0103] A remote unlocking unit 402, used for remotely sending an unlocking instruction to the outdoor wireless digital host 100;

[0104] The emergency alarm processing unit 403 is used to receive the alarm command sent by the outdoor wireless digital host 100 in real time and issue an alarm, and to obtain the alarm command to locate the target position where the alarm is issued and control the camera image of the target position area in the monitoring display screen to enlarge and display;

[0105] The abnormal capture unit 404 is used to receive the visitor capture pictures taken by the camera module 115, such as strangers wandering at the door of the unit building for more than 3 minutes, and is configured to: identify whether the face is a registered person through a lightweight YOLO algorithm. If it is determined to be a non-registered person, an alarm is issued to remind the property staff.

[0106] Specifically, the lightweight YOLO algorithm is implemented in the following way:

[0107] Channel pruning is performed on the original YOLOv5 model, reducing the number of parameters by 60% and lowering the hardware deployment cost;

[0108] INT8 quantization is adopted, increasing the inference speed by 3 times and supporting real-time 30fps video stream analysis;

[0109] Automatically adjust the face recognition confidence threshold according to the light intensity (e.g., lower the threshold in strong light to avoid missed reports and raise the threshold in weak light to reduce false reports) to ensure that the false alarm rate < 1%.

[0110] The workflow of abnormal capture is as follows:

[0111] The camera module detects that the target stays at the entrance of the unit building for > 3 minutes;

[0112] The abnormal capture unit starts lightweight YOLO analysis: set the input as a 1280x720@30fps video stream, and the output as a face feature vector + behavior label;

[0113] The access control management unit performs feature comparison. When it is determined to be a stranger, the emergency alarm unit triggers an audible and visual alarm.

[0114] As described above, the access control management unit 401 integrates face, mobile phone, password, and traditional access card information to form a multi-factor identity authentication system, taking into account both convenience and security. The remote unlocking unit 402 supports remote authorization unlocking by property management or residents, especially suitable for visitor management scenarios, improving the user experience. The abnormal capture unit 404 realizes triple optimization through a lightweight YOLO algorithm, improving the effect of captured photos. At the same time, it cooperates with behavior analysis linkage. For example, when a stranger is detected wandering for more than 3 minutes, an alarm is automatically triggered and pushed to the property management, providing a basis for abnormal determination; after the captured image by the camera module 115 is analyzed by YOLO, the feature vector is compared with the access control database 401, and when a stranger is determined, the emergency unit 403 is triggered, forming an efficient collaboration. Through the setting of the emergency alarm unit 403, it is convenient to quickly lock the incident area after receiving the alarm instruction and automatically zoom in on the camera image of the target area on the monitoring display screen to assist the security personnel in making decisions. In this way, a highly reliable security management solution is provided for old communities applying the intercom system of this case.

[0115] As Figure 3 shown, in specific implementation, each wireless repeater 200 further includes: a dynamic IP connection module 203 responsible for dynamic allocation of IP addresses, and a second power supply module 204 for powering each module of the wireless repeater;

[0116] Among them, the dynamic IP connection module 203 includes:

[0117] A processor chip 2031 that supports the DHCP protocol (such as model W7500P), which is connected to the second ESP wireless module 201 and is used to start the DHCP protocol when a new wireless indoor extension 300 is detected to be connected.

[0118] An IP address memory 2032, which is connected to the processor chip 2031 through the I2C bus and is used to store an assignable IP address pool such as 192.168.1.100 - 200; specifically, an EEPROM chip can be used, such as a chip with model AT24C256.

[0119] A network interface controller 2033, which is used to communicate with the upper - level node through Ethernet; the network interface controller 2033 can specifically use a PHY chip with model LAN8720A; it is dedicated to handling the Ethernet communication with the host 100, including extension information synchronization, status reporting, etc. In this way, through the setting of the dynamic IP connection module 203, it is convenient for the new wireless indoor extension to be plug - and - play, automatically assign an IP for the wireless indoor extension, without manual IP setting, reducing the operation and maintenance cost.

[0120] In specific implementation, since the third ESP wireless module 301 has a built - in Mesh protocol stack, it automatically starts the scanning mode after being powered on. The third ESP wireless module 301 initializes, scans the broadcast signals of the surrounding wireless repeaters 200, selects the node with the strongest RSSI and the optimal network level as the parent node; completes the identity authentication through WPA3 encryption and sends a registration request to the parent node (wireless repeater). The network interface controller of the dynamic IP connection module 203 of the parent node synchronizes the extension information to the memory 14 of the outdoor wireless digital host 100 to complete the binding. In this way, the dynamic IP connection module 203 assigns a unique IP address to the wireless repeater 200 and the connected sub - devices through the second ESP wireless module 201. The wireless indoor extension 300 is used to be bound to the household room and automatically join the Mesh network after being powered on.

[0121] The specific working process for the new wireless indoor extension to access is as follows:

[0122] The third ESP wireless module 301 of the wireless indoor extension scans the Mesh network, selects the parent node (wireless repeater) and completes the WPA3 authentication. The second ESP module 201 of the parent node records the extension MAC address and triggers the DHCP process of the dynamic IP connection module by sending a "new device access" instruction. The processor chip 2031 queries the available IP pool (192.168.1.100 - 200) from the IP address memory and generates a DHCPOFFER. The second ESP module 201 encapsulates the DHCPOFFER into a Mesh protocol frame and sends it to the extension through the wireless link.

[0123] After the extension accepts the configuration, it sends a "configuration completed" confirmation frame through the Mesh network. The second ESP module 201 of the parent node sends the extension IP / MAC information to the dynamic IP connection module 203. The network interface controller 2033 encapsulates the synchronization data according to the TCP / IP protocol and sends it through Ethernet to the memory 14 of the outdoor wireless digital host 100, achieving a consistent network-wide state.

[0124] As Figure 2 shown, in specific implementation, the outdoor wireless digital host 100 further includes:

[0125] An environment adaptation module 119 connected to the main control CPU module 103, and the environment adaptation module 119 includes:

[0126] A temperature and humidity sensor 1191 for real-time monitoring of environmental temperature and humidity;

[0127] An air pressure sensor 1192 for detecting rainfall or air pressure changes;

[0128] An ambient light sensor 1193 for sensing the ambient light intensity;

[0129] The first Wi-Fi module 102 dynamically adjusts its own transmission power through a power dynamic adjustment mechanism;

[0130] Among them, the dynamic adjustment mechanism includes:

[0131] When the temperature detected by the temperature and humidity sensor 1191 is higher than the preset temperature, it is determined that it is in a high-temperature environment (such as the temperature is greater than 55 degrees Celsius), and it automatically switches to the 5GHz band and increases the transmission power to compensate for the high-temperature signal attenuation;

[0132] When rainfall is detected by the air pressure sensor 1192, it automatically switches to the 2.4GHz band and increases the transmission power to compensate for the rain fade effect; the rain fade effect has a significant impact on high-frequency signals, and the 2.4GHz band has stronger penetration ability for rain and fog, thus compensating for the rain fade.

[0133] When no human activity is detected by the ambient light sensor 1193, it switches to the sleep mode and only retains the heartbeat packet monitoring.

[0134] As described above, in this case, through the environment adaptive module 119, three types of sensors, namely temperature and humidity sensor, barometric pressure sensor, and ambient light sensor, are integrated to achieve real-time monitoring of key environmental factors such as high temperature, rainfall, and light intensity. Through the dynamic adjustment mechanism, it automatically switches between the 2.4GHz and 5GHz frequency bands according to environmental parameters to balance signal penetration and bandwidth requirements. When the temperature exceeds the preset threshold, the system automatically switches to the 5GHz frequency band and increases the transmission power to effectively offset the signal attenuation caused by high temperature (such as the increased path loss caused by the change in air density). And when it is raining, it is linked and adjusted through the barometric pressure sensor, switches to the 2.4GHz frequency band and increases the power to compensate for the scattering and absorption effects of rainwater to ensure the stability of the communication link. When the ambient light sensor detects no human activity, the device enters the sleep mode, only retaining the heartbeat packet listening function to reduce power consumption.

[0135] The working principle of the intercom system in this case is as follows:

[0136] The outdoor wireless digital host 100, multiple wireless repeaters 200, and multiple wireless indoor handsets 300 in this system are each equipped with an ESP wireless module and build a self-organizing multi-hop wireless network (MESH network) based on the ESP-WIFI-MESH protocol. The wireless repeater 200, as a node, preferentially selects a path with strong signal (high RSSI) and few hops to transmit data. The wireless indoor handset 300 automatically accesses the network after completing the WPA3 encryption authentication by scanning the optimal parent node (wireless repeater), and its authentication information is synchronized to the host 100 to achieve full-network binding.

[0137] In the audio and video transmission process, when a visitor presses the digital button on the outdoor wireless digital host, the first audio input module (such as a microphone) collects the voice signal. The first digital-to-analog and analog-to-digital conversion module 108 converts the analog voice signal into a digital signal. The voice digital signal is processed and compressed into a voice signal data packet by the main control CPU module and is transmitted to the target wireless indoor handset through the MESH network composed of the first ESP wireless module 101. After the resident in the room where the corresponding wireless indoor handset is located answers, it is output through the second audio output module. The resident presses the button on the button module to trigger a reverse call signal. The second audio input module receives the call signal and converts the received digital call signal into an analog call signal through the second digital-to-analog and analog-to-digital conversion module, and forwards it to the wireless repeater and then to the outdoor wireless digital host through the Mesh network (i.e., the self-organizing multi-hop wireless network). The real-time data of the whole process is cached by the memory to support multi-channel concurrency. Moreover, when the resident presses the unlock button on the wireless indoor handset, the unlock instruction is also sent to the main control CPU module of the outdoor wireless digital host through the Mesh network, so that the lock control module controls the electromagnetic lock to unlock.

[0138] In addition, the system scalability is achieved through the Ethernet communication module for cross-building or cloud interconnection. The first WiFi module of the outdoor wireless digital host and the second WiFi module of the wireless repeater support Internet access, providing the wireless indoor extension with the ability of firmware remote upgrade and smart home linkage, forming an efficient, secure, and scalable wireless building intercom solution. The Ethernet module can communicate with the outdoor hosts of other buildings or with the community integrated management platform 400 through the TCP / IP protocol, and can also be communicatively connected to the network interface controller of the wireless repeater.

[0139] In summary, through the dual-mode design of "ESP dedicated network to ensure core functions + WiFi extended network to support value-added services" in the first embodiment of this case, it not only breaks through the wiring dependence and scalability bottleneck of traditional building intercom systems, but also avoids the high costs and power consumption problems of the all-WiFi solution, providing an intelligent solution with reliability, economy, and scalability for the renovation of old communities.

[0140] Embodiment 2

[0141] A self-organizing wireless intercom method for the renovation of old communities, characterized in that it is applied to the self-organizing wireless intercom system described in Embodiment 1, and includes the following steps:

[0142] Alarm trigger and priority marking: When the user presses the alarm button of the outdoor wireless digital host or the alarm button of the wireless indoor extension, an alarm instruction is generated and encrypted into an alarm packet, and a priority marking instruction is triggered to mark the alarm packet as the first priority, and the first priority is the highest priority;

[0143] Outdoor host call process: When a visitor initiates a call through the outdoor wireless digital host, voice data of the intercom call signal is generated and encapsulated into a voice data packet; if the outdoor host is equipped with a camera, video stream data is synchronously generated and encapsulated into a video data packet; a priority marking instruction is triggered to mark the voice data packet as the second priority and the video data packet as the third priority;

[0144] Indoor extension intercom trigger: When the user presses the intercom button of the wireless indoor extension, voice data and video stream data of the intercom call signal are generated, respectively encapsulated into a voice data packet and a video data packet, and a priority marking instruction is triggered to mark the voice data packet as the second priority and the video data packet as the third priority;

[0145] Multi-hop transmission mechanism: The alarm packet, voice data packet, and video data packet are multi-hop transmitted through multiple wireless repeaters, and the transmission order is dynamically scheduled according to the priority level during the transmission process to ensure the priority transmission of the first priority data;

[0146] Extension response and interaction: The target wireless indoor extension receives voice data packets and video data packets at one time and decodes them. If the decoding is successful, it triggers ringing and displays a picture. The resident conducts voice visual intercom or remote unlocking operation through the extension;

[0147] System-level priority rules: The ad-hoc wireless intercom system processes data transmission in the order of the first priority, the second priority, and the third priority. The alarm packet can preempt the voice and video data channels, and the voice data packet is given priority over the video data packet for transmission.

[0148] As described above, in the intercom method of this case, the alarm instruction is marked as the first priority and can preempt the voice / video channel to ensure the emergency signal is transmitted without delay. So that in the event of a sudden security incident, the alarm data can reach the property or resident terminal first through multi-hop relay, shortening the response time. Moreover, the alarm packet is encrypted to prevent information leakage and enhance the privacy protection ability of the weak security links in old communities. At the same time, in this case, the voice (second priority) is given priority over the video (third priority) to balance the real-time interaction requirements and bandwidth resources, facilitating the instant connection of voice and the subsequent transmission of the video stream when a visitor calls, so as to avoid network congestion. In this way, the system dynamically schedules the transmission order according to the priority, ensuring the stable transmission of key data (such as alarms and voices) in the old community environment with limited bandwidth and improving the communication efficiency. And because the intercom system of this case is used, through the MESH ad-hoc network of the outdoor wireless digital host, wireless repeater, and wireless indoor extension, and in cooperation with the local area network of the community to expand the coverage, the problem of signal dead zones caused by dense buildings and many obstructions in old communities is solved, enabling the alarm signal to cross obstacles and ensuring reliable reception by the property center. And the resident triggers the intercom or remote unlocking with one key through the extension, and the ringing response mechanism improves the operation convenience, especially suitable for the elderly or quick operations in emergency scenarios. In addition, this case also supports camera expansion (such as synchronizing the video stream when a visitor calls), taking into account the basic voice function and upgrade requirements, and adapting to the renovation budgets and technical conditions of different old communities.

[0149] As a preferred implementation manner, the alarm packet transmission method includes the following steps:

[0150] In the alarm packet data transmission path, the AES_GCM_256 encryption algorithm is used to encapsulate the alarm packet to ensure data confidentiality and integrity;

[0151] Explicitly mark the highest transmission priority through the QoS field in the packet header, triggering the ad-hoc wireless local area network to execute the highest-level transmission mechanism;

[0152] Among them, the highest-level transmission mechanism includes:

[0153] When an alarm packet is detected, immediately interrupt the current non-emergency data transmission and reserve dedicated channel resources to ensure real-time performance;

[0154] Select the path with the highest score as the transmission path according to the first transmission path scoring formula;

[0155] Adopt the collision avoidance algorithm (CSMA / CA), and fix the backoff window of the alarm packet to 2 time slots (the normal data is 16 - 64 time slots); The backoff window in the CSMA / CA algorithm is used to determine how long a node needs to wait after detecting that the channel is busy before attempting to send data again. The larger the backoff window, the longer the node may wait, thus reducing the probability of collision because the node has a longer random backoff time to choose.

[0156] Among them, the first transmission path scoring formula is preferably:

[0157] Path score = RSSI × 0.8 + (1 / number of hops) × 0.2. Among them, RSSI represents the signal strength: the range is usually negative (such as -30dBm to -90dBm), and the larger the value (closer to 0), the stronger the signal. The weight M is taken as 0.8 (greater than 0.5), emphasizing that the signal quality is more important for the path than the number of paths. The fewer the number of hops, the shorter the path, and the lower the probability of delay and packet loss. 1 / number of hops means that when the number of hops increases, the score of this item drops sharply (for example, when the number of hops = 1, the score is 1; when the number of hops = 2, the score is 0.5), punishing the long path. The weight N is taken as 0.2 (less than 0.4) as an auxiliary index to balance the signal strength and the path length. For example: Path A: RSSI = -50dBm, number of hops = 3 → score = (-50 × 0.8) + (1 / 3 × 0.2) = -40 + 0.067 ≈ -39.93

[0158] Path B: RSSI = -60dBm, number of hops = 2 → score = (-60 × 0.8) + (0.5 × 0.2) = -48 + 0.1 = -47.9; In this way, select Path A (although the number of hops is more, but the signal is stronger).

[0159] As described above, in this case, when sending the alarm packet through the advanced transmission mechanism, the node sends a control frame to reserve the channel, forcing other nodes to delay transmission. At the same time, through the collision avoidance algorithm, the backoff window of the alarm packet is fixed to 2 time slots, which is much smaller than the 16 - 64 time slots of the normal data. Although a small backoff window usually increases the collision risk, due to the channel reservation in this case, conflicts are avoided; moreover, the alarm packet is usually sporadic, and even if the backoff window is small, the actual collision probability is still lower than that of the frequently sent normal data; in this way, both the collision risk is reduced and the waiting time of the node is reduced. Select the path with the highest score as the transmission path according to the transmission path scoring formula, so as to select a path with strong signal and few hops, improving the overall network efficiency.

[0160] As a preferred implementation manner, the method in this case includes:

[0161] In the voice packet data transmission path, the UDP protocol is used to transmit voice data packets. The dynamic routing optimization algorithm is combined to monitor the network topology in real time, and the optimal path that avoids high-load nodes or interference areas is selected.

[0162] The implementation steps of the dynamic routing optimization algorithm include:

[0163] Link quality assessment: Real-time collection of RSSI, packet loss rate, and delay time of each path;

[0164] Select the path with the highest score as the transmission path according to the second transmission path scoring formula;

[0165] Among them, the second transmission path scoring formula is:

[0166] Second path score = A1×RSSI + A2×(1 / delay) + A3×(1 - packet loss rate).

[0167] Set the path switching mechanism: Set the path switching mechanism. If the score of the current path drops by more than the preset threshold B, and the score of the backup path is higher than the preset percentage value C, then switch the path within the preset T time, where B takes 15 - 30%, C takes 20 - 30%, and T takes 5 - 15ms.

[0168] In specific implementation, A1 takes 0.5, A2 takes 0.3, A3 takes 0.2, B takes 15%, C takes 20%, and T takes 10ms.; Second path score = 0.5×RSSI + 0.3×(1 / delay time) + 0.2×(1 - packet loss rate); If the score of the current path drops by more than 15%, and the score of the backup path is higher than 20%, then switch the path within 10ms;

[0169] Take the following example:

[0170] Path 1: RSSI = -55dBm, delay time = 80ms, packet loss rate = 2%

[0171] Path 2: RSSI = -60dBm, delay time = 60ms, packet loss rate = 1%

[0172] Calculate the score:

[0173] Path 1 score = 0.5(-55) + 0.3(1 / 80) + 0.2*(1 - 0.02) = -27.5 + 0.00375 + 0.196 = -27.301

[0174] Path 2 score = 0.5(-60) + 0.3(1 / 60) + 0.2*(1 - 0.01) = -30 +

[0175] 0.005 + 0.198 = -29.807

[0176] The selected path 1 has a higher score, and the stable link path 1 is preferentially selected for transmission.

[0177] When there is interference in path 1 during the transmission process, the RSSI drops suddenly to -70 dBm, the delay rises to 120 ms, and the packet loss rate rises to 8%.

[0178] New score: 0.5(-70)+0.3(1 / 120)+0.2*(1 - 0.08)= -35 +

[0179] 0.0025 + 0.184 = -34.8135; while the score of path 2 is still -29.807. At this time, the score of path 2 is 16.8% higher than that of path 1 (exceeding the preset B = 15%). Trigger the handover: Switch to path 2 within T = 10 ms to quickly restore the voice quality.

[0180] As described above, the method of this case transmits voice data packets by adopting the UDP protocol to balance the transmission reliability and protocol overhead; by using the second transmission path scoring formula to select the path with the highest score as the transmission path, the end-to-end delay of the voice packets can be reduced; by cooperating with the path switching mechanism, it can be flexibly switched when the transmission path is interfered, ensuring that the voice data is always transmitted in a better transmission path and improving the transmission efficiency. The weight relationship A1 > A2 > A3 is set in the dynamic routing optimization algorithm because the RSSI directly reflects the signal quality of the wireless link. Insufficient signal strength will lead to an increase in the bit error rate, an increase in the packet loss rate, and even communication interruption. Even if the delay or packet loss rate meets the standards temporarily, if the signal strength remains low, the link stability will be difficult to guarantee. Among the paths with similar RSSI, the delay becomes the key differentiating factor. The delay directly affects the usability of voice communication (whether the conversation can be smooth), while the packet loss rate more affects the voice quality (conversation clarity). In scenarios where the real-time requirement is higher than the voice quality (such as tactical communication and emergency dispatch), giving priority to ensuring the delay can avoid conversation interruption caused by network jitter, and at the same time, make up for the impact of packet loss through codec technology to achieve a balance between experience and efficiency. Preferentially selecting the low-delay path can improve the real-time interactivity. The packet loss rate is usually the result of insufficient signal strength or increased delay jitter. After preferentially optimizing the RSSI and delay, the packet loss rate often improves naturally without the need to assign too high a weight separately. Therefore, the setting of A1 > A2 > A3 can further improve the transmission efficiency on the premise of signal stability, balancing the reliability and real-time requirements of voice transmission

[0181] In the video packet data transmission path, the video data is compressed by H.265 encoding, and the low-latency mode (GOP = 1 and B frames are disabled) is configured. Specifically, when implementing, the low-latency mode of H.265 encoding is enabled, GOP = 1 is set and B frames are disabled, and the IDR frame interval is forced to be 1 second; in this way, the end-to-end latency can be compressed to the single-frame processing time (≤1ms) through an extremely simple encoding structure, reducing the bandwidth occupancy.

[0182] The above has introduced in detail a self-organizing wireless intercom system and method for the renovation of old residential areas disclosed in the embodiments of the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A self-organizing wireless intercom system for the renovation of old residential areas, characterized in that: include: A plurality of outdoor wireless digital hosts (100), each comprising a first ESP wireless module (101), a first WiFi module (102) and a main control CPU module (103); the first ESP wireless module (101) and the first WiFi module (102) are interactively connected to the main control CPU module (103) respectively; A plurality of wireless repeaters (200), each comprising a second ESP wireless module (201) and a second WiFi module (202); A plurality of wireless indoor extensions (300), each comprising a third ESP wireless module (301); The first ESP wireless module (101), the second ESP wireless module (201), and the third ESP wireless module (301) are all wireless communication modules supporting the Mesh protocol; the outdoor wireless digital host (100), the plurality of wireless repeaters (200), and the plurality of wireless indoor extensions (300) are wirelessly connected through their respective ESP wireless modules and self-compose a wireless local area network; The outdoor wireless digital hosts (100) in different buildings communicate with each other through the community local area network.

2. The ad hoc wireless intercom system according to claim 1, characterized in that: Each outdoor wireless digital host (100) further comprises: a memory (104), a first audio input module (105), a first audio output module (106), a Flash memory (107), a first digital-to-analog and analog-to-digital conversion module (108), a lock control module (109), a liquid crystal display (110), a numeric keyboard (111), and a first power supply module (112) for supplying power to each module of the outdoor wireless digital host (100); the main control CPU module (103) is also interactively connected to the memory (104), the Flash memory (107), the first digital-to-analog and analog-to-digital conversion module (108), the lock control module (109), the liquid crystal display (110), and the numeric keyboard (111); the first ESP wireless module (101) sends a voice signal data packet to the wireless indoor extension (300) or receives an intercom signal from the wireless indoor extension (300) through a plurality of wireless repeaters (200); The first digital-to-analog and analog-to-digital conversion module (108) is electrically connected to the first audio input module (105) and the first audio output module (106) respectively; the lock control module (109) is used to receive the unlocking instruction sent by the main control CPU module (103) to unlock and lock; Each wireless indoor extension (300) further comprises: a second audio input module (302), a second audio output module (303), a second digital-to-analog and analog-to-digital conversion module (304), a key module (305), and a third power supply module (306) for supplying power to each module of the wireless indoor extension (300); the second ESP wireless module (301) sends intercom signals to the outdoor wireless digital host (100) or receives voice signal data packets from the wireless indoor extension (300) through a plurality of wireless repeaters (200); The second digital-to-analog and analog-to-digital conversion module (304) is electrically connected to the second audio input module (302) and the second audio output module (303) respectively.

3. The ad hoc wireless intercom system according to claim 2, characterized in that: Also includes: The community comprehensive management platform (400) is set up in the property center and is used to monitor the community status; Each outdoor wireless digital host (100) and the community integrated management platform (400) communicate with each other through the community local area network; Each outdoor wireless digital host (100) further comprises a first alarm module (113), an Ethernet communication module (114), a camera module (115), a face recognition module (116), an NFC module (117) and a fingerprint recognition module (118) which are interactively connected to the main control CPU module (103) respectively; The first alarm module (113) includes a first alarm button (1131), and when it is detected that the first alarm button (1131) is continuously pressed for more than a preset number of seconds, an alarm instruction is triggered; the alarm instruction is sent to the community local area network through the Ethernet communication module (114) or the first WiFi module (102), and then forwarded to the community integrated management platform (400); Each wireless indoor extension (300) further comprises a second alarm module (307), wherein the second alarm module (307) comprises a second alarm button (3071), and when it is detected that the second alarm button (3071) is continuously pressed for more than a preset number of seconds, an alarm instruction is triggered; the alarm instruction is sent to the outdoor wireless digital host (100) via the self-organizing wireless local area network of the third ESP wireless module (301), and then forwarded by the outdoor wireless digital host (100) to the community integrated management platform (400) via the community local area network.

4. The ad hoc wireless intercom system according to claim 3, characterized in that: The community integrated management platform (400) comprises: The access control management unit (401) is used to store the resident's facial feature template, mobile phone number, unlocking password and original access control card information; A remote unlocking unit (402), used for remotely sending an unlocking instruction to an outdoor wireless digital host (100); An emergency alarm processing unit (403) is used to receive an alarm instruction sent by an outdoor wireless digital host (100) in real time and send out an alarm, and to obtain the alarm instruction to locate the target position where the alarm is sent out and control the camera image in the area where the target position is located on the monitoring display screen to be enlarged and displayed; The abnormal capture unit (404) is used to receive the visitor snapshot pictures taken by the camera module (115), and is configured to: identify whether the face of the visitor is a registered person through a lightweight YOLO algorithm, and if it is determined to be a non-registered person, issue an alarm to remind the property staff.

5. The ad hoc wireless intercom system according to claim 1, characterized in that: Each wireless repeater (200) further comprises: a dynamic IP connection module (203) responsible for the dynamic allocation of IP addresses, and a second power supply module (204) for supplying power to each module of the wireless repeater (200); Wherein, the dynamic IP connection module (203) comprises: A processor chip (2031) supporting the DHCP protocol, which is connected to the second ESP module (201) and is used to start the DHCP protocol when detecting that a new wireless indoor extension (300) is connected; An IP address memory (2032), connected to the processor chip (2031), for storing an allocatable IP address pool; The network interface controller (2033) is used to communicate with the upper node via Ethernet.

6. The ad hoc wireless intercom system according to any one of claims 2 to 4, characterized in that: The first WiFi module (102) uses a WiFi chip that supports 2.4 GHz and 5 GHz dual-band communications; The outdoor wireless digital host (100) further comprises: An environment adaptation module (119) connected to the main control CPU module (103), the environment adaptation module (119) comprising: A temperature and humidity sensor (1191) is used to monitor the ambient temperature and humidity in real time; A pressure sensor (1192) for detecting rainfall or changes in air pressure; An ambient light sensor (1193) for sensing ambient light intensity; The first WiFi module (102) dynamically adjusts its own transmission power through a dynamic power adjustment mechanism; The dynamic adjustment mechanism includes: When the temperature and humidity sensor (1191) detects that the temperature is higher than the preset temperature, it is determined that the environment is in a high temperature environment, and automatically switches to the 5 GHz frequency band and increases the transmission power to compensate for the high temperature signal attenuation; When rainfall is detected by the air pressure sensor (1192), the frequency band is automatically switched to 2.4 GHz and the transmission power is increased to compensate for the rain attenuation effect; Switching to sleep mode when no human activity is detected by the ambient light sensor (1193).

7. A self-organizing network wireless intercom method for the renovation of old residential areas, characterized in that: The self-organizing network wireless intercom system according to any one of claims 1 to 6 comprises the following steps: When the user presses the alarm button of the outdoor wireless digital host or the alarm button of the wireless indoor extension, an alarm instruction is generated and encrypted into an alarm packet, triggering a priority marking instruction to mark the alarm packet as the first priority, which is the highest priority; When a visitor initiates a call through the outdoor wireless digital host, voice data of the intercom call signal is generated and encapsulated into a voice data packet, triggering a priority marking instruction to mark the voice data packet as the second priority; if the outdoor wireless digital host is equipped with a camera, video stream data is synchronously generated and encapsulated into a video data packet, triggering a priority marking instruction to mark the video data packet as the third priority; When the user presses the intercom button of the wireless indoor extension, the voice data and video stream data of the intercom call signal are generated, which are respectively encapsulated into a voice data packet and a video data packet, triggering a priority marking instruction to mark the voice data packet as the second priority and the video data packet as the third priority; The alarm packet, voice data packet and video data packet are transmitted in multiple hops through multiple wireless repeaters, and dynamically scheduled according to the priority level during the transmission process to ensure that the first priority data is transmitted first; The target wireless indoor extension receives the voice data packet and the video data packet at one time and decodes them. If the decoding is successful, the ringing and the display screen are triggered. The resident can use the extension to perform voice visual intercom or remote unlocking operations; The self-organizing network wireless intercom system processes data transmission in the order of the first priority, the second priority, and the third priority, wherein the alarm packet occupies the voice and video data channels, and the voice data packet is transmitted in priority to the video data packet.

8. The wireless intercom method according to claim 7, characterized in that: In the alarm packet data transmission path, the alarm packet is encapsulated by the AES encryption algorithm, marked as the highest transmission priority higher than the voice data packet through the packet header, and the highest level transmission mechanism is implemented through the self-organizing wireless LAN to ensure that it has priority in obtaining channel resources; In the voice packet data transmission path, the UDP protocol is used to transmit voice data packets, and the dynamic routing optimization algorithm is combined to monitor the network topology in real time to avoid the optimal path of high-load nodes or interference areas; In the video packet data transmission path, video data is compressed through H.265 encoding and a low latency mode is configured.

9. The wireless intercom method according to claim 8, characterized in that: The highest level transport mechanisms include: When an alarm packet is detected, the current non-urgent data transmission is immediately interrupted and dedicated channel resources are reserved to ensure real-time performance; Selecting the path with the highest score as the transmission path according to the first transmission path scoring formula; Using CSMA / CA algorithm, the alarm packet backoff window is fixed at 2 time slots; Among them, the first transmission path scoring formula is: First path score = RSSI × M + (1 / number of hops) × N; RSSI represents signal strength, M represents RSSI influence weight ratio, and N represents number of hops influence weight ratio; Among them, 0.4≤M≤0.8, 0.2≤N≤0.6, and M+N=1.

10. The wireless intercom method according to claim 8, characterized in that: The implementation steps of the dynamic routing optimization algorithm include: Collect RSSI, packet loss rate and delay time of each path in real time; Selecting the path with the highest score as the transmission path according to the second transmission path scoring formula; Among them, the second transmission path scoring formula is: Second path score = A1 × RSSI + A2 × (1 / delay time) + A3 × (1-packet loss rate), where RSSI represents signal strength, A1 represents RSSI impact weight ratio, A2 represents delay data impact weight ratio, A3 represents packet loss rate impact weight ratio, A1 + A2 + A3 = 1, A1 > A2 > A3; The path switching mechanism is set. If the current path score drops below the preset threshold value B, and the backup path score is higher than the preset ratio value C, the path is switched within the preset time T, where B is 15-30%, C is 20-30%, and T is 5-15ms.

Images