Introduction
Industrial Wireless Access Points (Industrial WiFi APs) play a critical role in modern industrial communication networks by connecting field devices with centralized control and monitoring systems.
In smart factories, Industrial IoT (IIoT), automation systems and remote monitoring applications, large amounts of industrial data must be transmitted reliably between:
- PLC controllers
- Sensors
- Industrial cameras
- Robots
- AGV/AMR systems
- IoT gateways
Unlike traditional wired communication, wireless communication transfers information through radio waves. To achieve reliable data transmission, an Industrial Wireless Access Point must complete a series of complex communication processes, including:
- Data processing
- Source coding
- Channel coding
- Modulation
- Wireless transmission
- Signal reception and decoding
- Network forwarding
Understanding these technologies helps explain why industrial wireless communication requires more than standard WiFi equipment.
Industrial WiFi solutions must provide:
- Stable wireless connectivity
- Strong anti-interference capability
- High terminal capacity
- Reliable operation in challenging environments
Industrial Wireless Communication Process Overview
The basic communication process between an industrial terminal and an Industrial AP is:
The Industrial AP acts as the communication bridge between wireless devices and industrial networks.
1. Source Coding: Converting Industrial Information into Digital Data
Industrial devices generate different types of information.
Examples:
- Sensors generate temperature, pressure and vibration data
- Cameras generate video streams
- PLCs generate control commands
- Robots generate motion information
Before wireless transmission, the original information must be converted into digital data.
This process is called:
Source Coding
Source coding converts original information into digital signals while reducing unnecessary data redundancy.
The main purposes are:
- Reduce data size
- Improve transmission efficiency
- Optimize bandwidth usage
- Maintain required information accuracy
Examples of Source Coding in Industrial Applications
Different types of industrial data require different processing methods.
Industrial Video
Industrial cameras generate large amounts of image data. Compression technologies such as:
- H.264
- H.265
are commonly used to reduce bandwidth requirements.
Sensor Data
Industrial sensors usually generate smaller data packets, including:
- Temperature values
- Pressure measurements
- Equipment status
- Environmental information
Efficient digital encoding allows large numbers of sensors to communicate through wireless networks.
Control Data
PLC and automation systems require accurate and timely transmission. Control commands are converted into digital packets suitable for reliable network communication.
2. Channel Coding: Improving Wireless Communication Reliability
Wireless communication is naturally vulnerable to interference. Industrial environments create additional challenges, including:
- Motors
- Variable frequency drives
- Welding equipment
- Electrical systems
- Metal structures
These factors may cause:
- Signal degradation
- Packet errors
- Data loss
To improve transmission reliability, WLAN systems use:
Channel Coding Technology
How Channel Coding Works
Channel coding adds additional error detection and correction information to transmitted data. When the receiver detects transmission errors, it can use this additional information to recover the original data.
Benefits include:
- Lower error rates
- Improved communication stability
- Better performance in noisy environments
Common WLAN Channel Coding Technologies
BCC (Binary Convolutional Coding)
BCC is an earlier error correction technology used in traditional wireless communication systems. It provides basic error correction capability.
LDPC (Low-Density Parity Check)
LDPC provides stronger error correction performance compared with traditional coding methods. It is widely used in:
- WiFi 5
- WiFi 6
- WiFi 7
Advantages include:
- Higher reliability
- Better transmission efficiency
- Improved performance in complex RF environments
For industrial applications, LDPC helps maintain stable communication even when wireless signals are affected by interference.
3. Modulation: Converting Digital Data into Wireless Signals
Digital data inside electronic circuits cannot directly travel through the air. Before transmission, digital signals must be converted into radio frequency signals.
This process is called:
Modulation
The purpose of modulation is to load digital information onto high-frequency carrier waves. The modulation process mainly includes:
- Symbol mapping
- Carrier modulation
QAM: Symbol Mapping Technology
A key technology used in WiFi systems is:
QAM (Quadrature Amplitude Modulation)
QAM represents digital information by changing:
- Signal amplitude
- Signal phase
Higher-order QAM can transmit more data within the same bandwidth. Common QAM technologies include:
- 64-QAM
- 256-QAM
- 1024-QAM
- 4096-QAM (WiFi 7)
Higher-order modulation improves transmission speed but requires better signal quality. Industrial wireless systems dynamically adjust modulation levels according to:
- Signal strength
- Interference conditions
- Network requirements
OFDM: Carrier Modulation Technology
Modern WLAN systems use:
OFDM (Orthogonal Frequency Division Multiplexing)
OFDM divides one wireless channel into multiple smaller subcarriers. Each subcarrier carries part of the transmitted data.
Advantages include:
- Higher data capacity
- Improved spectrum efficiency
- Better resistance against multipath interference
- More reliable communication
OFDM is used in:
- WiFi 5
- WiFi 6
- WiFi 7
4. MIMO Technology in Industrial WiFi Networks
Modern Industrial Wireless Access Points often use:
MIMO (Multiple Input Multiple Output)
MIMO uses multiple antennas to transmit and receive multiple data streams simultaneously.
Advantages:
- Higher throughput
- Better coverage
- Improved reliability
Common configurations include:
- 2×2 MIMO
- 3×3 MIMO
- 4×4 MIMO
MIMO technology is especially valuable in industrial environments where:
- Large coverage areas are required
- Multiple devices communicate simultaneously
- Signal reflection exists due to metal structures
5. Wireless Air Interface (Air Interface)
In wired networks, devices communicate through physical interfaces such as:
- Ethernet ports
- Fiber connectors
- Serial interfaces
Wireless networks do not use physical cables. Instead, devices communicate through electromagnetic waves. This invisible communication interface is called:
Air Interface
The air interface defines:
- Frequency usage
- Signal transmission method
- Communication protocol
Industrial WiFi networks commonly operate on:
- 2.4GHz
- 5GHz
- 6GHz
6. Wireless Channel
A wireless channel is the transmission path used by radio signals. IEEE 802.11 standards define:
- Frequency ranges
- Available channels
- Channel bandwidth
Common channel bandwidths:
- 20MHz
- 40MHz
- 80MHz
- 160MHz
A wider channel provides higher throughput but requires better RF conditions. Industrial Wireless APs use technologies such as:
- Automatic channel selection
- RF optimization
- Interference detection
to maintain stable communication.
How an Industrial AP Communicates with Wireless Terminals
The Complete Industrial Wireless Communication Process
The communication process between an industrial terminal and an Industrial Wireless Access Point involves multiple stages, from data generation and signal processing to wireless transmission and industrial system integration.
The process begins with industrial terminals, such as PLC controllers, sensors, industrial cameras and robots, which generate operational data during industrial processes.
The collected data is first processed through digital data processing, where the original information is converted into digital data packets suitable for network transmission.
The digital data then passes through source coding, which removes redundant information and improves transmission efficiency by compressing data while maintaining required accuracy.
After source coding, the data undergoes channel coding, which adds error detection and correction capabilities to improve wireless transmission reliability. This process helps reduce the impact of signal interference, noise and data errors in industrial environments.
The coded data is then converted into wireless signals through QAM and OFDM modulation technologies. QAM improves data transmission efficiency by mapping digital information into signal symbols, while OFDM divides the wireless channel into multiple subcarriers to increase spectrum utilization and communication reliability.
The modulated signals are transmitted through the wireless transmission channel using industrial WiFi frequency bands such as 2.4GHz, 5GHz and 6GHz.
The Industrial Wireless Access Point receives the wireless signals from industrial terminals, performs signal processing and forwards the data through an Ethernet or fiber network.
Finally, the transmitted data reaches industrial control systems, including:
- SCADA systems
- Industrial control platforms
- Cloud monitoring platforms
These systems analyze and manage industrial data for applications such as equipment monitoring, automation control, predictive maintenance and Industrial IoT.
Through this complete communication process, an Industrial Wireless Access Point provides a reliable connection between field devices and higher-level industrial systems, enabling efficient wireless communication in smart factories and industrial environments.
The Industrial AP performs:
- Wireless signal reception
- Data decoding
- Network packet processing
- Data forwarding
- Device management
Why Industrial WiFi Communication Requires Professional APs
Industrial environments are more challenging than offices. Industrial Wireless APs need to handle:
Electromagnetic Interference
From:
- Motors
- Machines
- Power equipment
High Device Density
Including:
- Sensors
- Cameras
- Robots
- AGVs
Continuous Operation
Industrial systems often require:
- 24/7 operation
- High reliability
- Long product lifecycle
Therefore, industrial wireless communication requires specialized hardware and optimized RF performance.
Frequently Asked Questions (FAQ)
Q1. How does an Industrial Wireless Access Point transmit data?
A: An Industrial Wireless Access Point transmits data by converting digital information into wireless signals through multiple communication processes.
The process includes:
- Source coding
- Channel coding
- Modulation
- Wireless transmission
Technologies such as QAM and OFDM convert digital data into radio signals, which are transmitted through antennas over 2.4GHz, 5GHz or 6GHz frequency bands. The Industrial AP receives the wireless signals, processes the data and forwards it through Ethernet or fiber networks to industrial control systems.
Q2. What are OFDM and QAM in industrial WiFi communication?
A: QAM and OFDM are key technologies used in modern WiFi communication.
QAM (Quadrature Amplitude Modulation) converts digital information into signal symbols by changing amplitude and phase.
OFDM (Orthogonal Frequency Division Multiplexing) divides a wireless channel into multiple subcarriers to improve transmission efficiency.
Together, they provide:
- Higher throughput
- Better spectrum utilization
- Improved wireless reliability
They are widely used in WiFi 5, WiFi 6 and WiFi 7 systems.
Q3. Why is channel coding important for industrial wireless communication?
A:Channel coding improves wireless reliability by adding error correction information to transmitted data. It helps reduce the impact of:
- Electromagnetic interference
- Signal attenuation
- Wireless noise
Technologies such as BCC and LDPC allow industrial wireless networks to maintain stable communication in challenging environments.
Q4. What frequency bands are used by Industrial WiFi networks?
A:Industrial WiFi networks commonly use:
- 2.4GHz: Longer range and better penetration
- 5GHz: Higher speed and lower interference
- 6GHz: More spectrum resources for WiFi 6E and WiFi 7
The appropriate frequency band depends on coverage, bandwidth requirements and environmental conditions.
Q5. How does Industrial WiFi reduce interference?
A:Industrial WiFi reduces interference through:
- Intelligent channel management
- RF optimization
- Advanced modulation technologies
- High-performance wireless chipsets
- Antenna design optimization
These technologies help Industrial Wireless APs maintain stable communication in factories and other complex industrial environments.