China Wireless modem Manufacturers, Serial server Factory https://blog.dnevnik.hr/zigbeemodule
srijeda, 30.11.2022.
Four defects of LoRaWAN wireless technology
Although the LoRaWAN wireless technology was built by the experts of LoRa Alliance (mainly Semtech, IBM, Actility), it ignores the complexity of technology and the high cost of hardware, and has defects in the following technical transmission.
1. Public bandwidth + public standards = vulnerable to attacks industrial iot gateway
LoRaWAN works on the free bandwidth of ISM (ISM), whose protocol specification is public, which brings the problem of being vulnerable to attack. It is difficult to "forge" an End Node. The attacker listens to the 4-byte DevAddr. When using this address to send a message, the gateway is a network server (NS of one of the four servers of Lora wan server).
Another attack is "malicious crowding". Imagine that if an attacker uses a LoRa device to send a preamble of the maximum length with a bandwidth of 125kHz, the channel will be maliciously occupied. As long as the attacker protects the duty cycle and transmission power, this attack is "legal". Policies or industry regulations may be needed to protect LoRaWAN from congestion attacks.
2. The inefficiency of the asynchronous ALOHA protocol
The state of Hawaii in the United States is an archipelago, and the cost of laying a wired network is very high. Using wireless technology allows users on each island to use the central computer. This project was in charge of by the University of Hawaii in 1968, and it is the earliest wireless computer communication network in the world. This communication protocol is called aloha, which is the greeting that people in Hawaii say hello to.
The principle of the protocol is very simple. If the user has data, let him send it. If the response is received within the specified time, it means the sending is successful, otherwise resend.
Resend strategy: Wait for a random time before resending. If a collision occurs again, wait a random amount of time until the resend succeeds.
Pros: Easy to implement.
Disadvantages: extremely easy to conflict
Efficiency: The maximum channel utilization rate of pure ALOHA protocol is below 18.4% (1/2e)
Today, the host Class A of LoRaWAN also adopts the ALOHA protocol. While saving power and simplicity, conflicts and low efficiency are inevitable. Fortunately, the sensor's communication data and frequency are not high, and SX1301 can provide multi-channel FDMA (Frequency Division Multiplexing), which can effectively alleviate conflicts.
ponedjeljak, 07.11.2022.
Long Range: Over 1Km distance via BLE
Long Range: Over 1Km distance via BLE
In previous timings, radio transmit power played a crucial role in increasing the range of BLE products. With the introduction of Bluetooth modules based on Nordic solutions, users are able to obtain better communication protocols. This module supports BLE 4.2/5 protocol. Bluetooth version 5 provides long-range mode. The design of this long-range wireless module provides considerable power efficiency while achieving a coverage range of over 1Km.
In these devices, Wi-Fi and Bluetooth communicate through serial ports for transparent data transfer. The long-range module helps extend the range of the Bluetooth connection to experience enhanced positioning; it also enables robust communication in areas modbus tcp gateway
where users encounter obstacles with previous wireless devices. In addition, Long Range also supports transparent signaling.
Achieving a range of more than 1 Km via BLE depends on the surrounding environment, antenna and radio signal performance. Therefore, there are many factors that can affect the working of Bluetooth range. Typically, they are:
`Antenna
a Physical obstacles in the data transmission path
b Receiver sensitivity
cTransmitter output power
BLE technology itself has limitations based on the use of modulation. Since the performance of the antenna and radio remains fairly static for a particular Bluetooth device, the surrounding environment varies widely. For example: people may get a range of up to 100 meters outdoors, which is a rare situation. In indoor Bluetooth positioning and navigation, obstacles such as concrete walls can reduce the strength of the radio signal. Therefore, the effective range is significantly reduced.
When creating a Bluetooth device, a manufacturer can choose to give it a better range. They can also move on by choosing the Bluetooth chip with the best receiver sensitivity. In addition, its output power should ensure that the device has a good antenna. But in some cases, users need to transmit data over hundreds and thousands of meters via Bluetooth technology. In this case, they use a different network to achieve a higher range of the bluetooth module.
petak, 04.11.2022.
Ebyte Cloud Platform - Construction of Smart Farm
With the popularization of IoT technology, various IoT application cases can be seen everywhere in our lives unconsciously. Such as shared bicycles neatly parked on the roadside, shared mopeds, smart sockets and smart appliances in the home; smart irrigation systems in agriculture; smart parking systems in cities are all classic cases of IoT applications. It is foreseeable that the emergence and implementation of a large number of high-quality IoT solutions in the near future will bring a better experience and more convenience to our lives.
In this article, we build a smart farm application scheme based on the Ebyte cloud platform and E870-D1G as the network IO controller.
First of all, we need to clarify what is a "smart farm": it is a kind of Internet of Things as the core foundation, through the materialization of various functional parts in the farm, combined with wireless technology, automatic control technology and database to achieve intelligent management farm.Remote IO module
The development of smart farms is mainly divided into three stages:
1. Traditional labor or manpower liberation, AC-DC dual
no need to enter the farm, only manpower is required for remote control on the console;
2. The farm is controlled by the host computer system, and the manager can directly control the host computer to complete all farm operations, and the host computer issues all control instructions;
3. Artificial intelligence is highly intelligent, and all operations do not need personnel to make decisions, and are all scheduled by unmanned systems.
| < | studeni, 2022 | > | ||||
| P | U | S | Č | P | S | N |
| 1 | 2 | 3 | 4 | 5 | 6 | |
| 7 | 8 | 9 | 10 | 11 | 12 | 13 |
| 14 | 15 | 16 | 17 | 18 | 19 | 20 |
| 21 | 22 | 23 | 24 | 25 | 26 | 27 |
| 28 | 29 | 30 | ||||
Lipanj 2024 (1)
Prosinac 2022 (3)
Studeni 2022 (3)
Listopad 2022 (2)
Rujan 2022 (3)
Kolovoz 2022 (3)
Srpanj 2022 (2)
Lipanj 2022 (3)
Svibanj 2022 (5)
Travanj 2022 (3)
Ožujak 2022 (3)
Dnevnik.hr
Gol.hr
Zadovoljna.hr
Novaplus.hr
NovaTV.hr
DomaTV.hr
Mojamini.tv
Opis bloga
Linkovi
SPI/SOC/UART Manufacturers
UART Module Company
UART Module
About us
Chengdu Ebyte Electronic Technology Co.,Ltd.is a high-tech enterprise which specializes in Internet of Things communications, has hundreds of self-developed products and unanimously recognized by customers. Our company has a strong R&D capabilities, with a perfect after-sale system, we provide customers with complete solutions and technical support,shorten the R&D cycle, reduce R&D costs, and provide a powerful platform for new products development.