What is wireless?

Industrial wireless tutorials: Wireless communication, unlike wired, relies an unbounded medium to transfer information. Wireless local area networks (WLANs) use electromagnetic radiation to transmit information between nodes without wires (a bounded, physical medium).

06/19/2014


Industrial Wireless Tutorials, a Control Engineering blog, discussed five wireless protocols. Courtesy: Control Engineering, Dan CapanoWireless communication, unlike wired, relies on an unbounded medium to transfer information. Wireless local area networks (WLANs) use electromagnetic radiation to transmit information between nodes without the use of a bounded, physical medium. As you would guess, this presents issues and problems unique to the medium. The air around us is alive with electromagnetic radiation. The challenge is to reliably and securely transfer information between two network nodes without significant errors or corruption.

In many environments, particularly industrial, the amount of electromagnetic interference, or EMI, is so significant that even the use of shielded cables is insufficient to guarantee error-free communication. In otherwise "clean" environments, interference generated by ordinary household items can render a radio channel useless-microwave ovens have taken down many a WLAN. Radio frequency (RF) technology can be very tricky to properly implement; even with vastly improved technology, problems can and do happen.

Before we get into specific technical detail, however, I want to review the different flavors of wireless technology in current use. Each iteration was developed to suit a specific need, and each is well suited to a specific function or data type. It should be noted that the technologies discussed here are in a broad category of low-power, wide-bandwidth technologies; these differ from commercial RF technology, such as that used in broadcasting, which is typically high-power, narrow-band transmission.

Aside from Wi-Fi, or IEEE 802.11, which will be covered in much greater detail, there are other familiar wireless technologies, which are defined by IEEE 802.15, Personal Area Networks (PANs). Briefly, Bluetooth, a short-range variant, was originally standardized by IEEE 802.15.1. Bluetooth uses a master-slave structure and a form of modulation called frequency hopping spread spectrum (FHSS).

Essentially, the carrier "hops" between forty 1 Mhz channels. Bluetooth is used for short-range communication in the 2.4 GHz ISM band and chiefly for audio delivery and simple control function, as with a mobile phone. (Bluetooth was named after 10thcentury Danish King Harald Bluetooth.) Another common protocol is Wi-HART, or WirelessHART. It conforms to the IEEE 802.15.4 standard and is used chiefly for short range communication among wireless capable HART devices. WirelessHART forms a mesh network between devices and the network gateway. WirelessHART uses both channel hopping and other forms of spread spectrum in the 2.4 GHz ISM band. (HART stands for Highway Addressable Remote Transducer. Learn more at www.hart.org.)

Z-Wave is another short range wireless technology used extensively in home automation and operates in the 900 MHz ISM band. Z-Wave also uses FHSS, and allows for the formation of a source routed mesh network.

Daniel E. Capano, owner and president, Diversified Technical Services Inc. of Stamford, Conn., is a certified wireless network administrator (CWNA) and writes posts for the Control Engineering blog, Industrial Wireless Tutorials.ZigBee is another short range technology that has had limited acceptance. It also adheres to the IEEE 802.15.4 standard and forms an ad hoc wireless mesh network in the 2.4 GHz ISM band. ZigBee provides a low data rate, but operates at low power over long distances through mesh connections. The name refers to the behavior of honeybees.

Wi-Max (Worldwide Interoperability for Microwave Access) is another wireless technology designed to provide widespread and robust wireless connectivity. Wi-Max is defined by the IEEE 802.16 standard and is similar to Wi-Fi but operates over a much greater coverage area; the proposed system is something of a hybrid of Wi-Fi and cellular principles. Wi-Max operates in the spectrum surrounding 2.4 GHz, 2.5GHz, and 3.5GHz, with throughputs of up to 1 Gbps.

- Daniel E. Capano, owner and president, Diversified Technical Services Inc. of Stamford, Conn., is a certified wireless network administrator (CWNA). Edited by Mark T. Hoske, content manager, CFE Media, Control Engineering, mhoske@cfemedia.com.

ONLINE extras

www.controleng.com/blogs has other wireless tutorials from Capano.

www.controleng.com/webcasts has wireless webcasts, some for PDH credit.

Control Engineering has a wireless page.



Engineers' Choice Awards
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by Control Engineering subscribers.
System Integrator Giants
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
System Integrator of the Year
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
How to Maximize Factory Automation Efficiency with Low Cost Machine Vision
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Wireless Reliability in Harsh Environments
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
Human Factors and the Impact on Plant Safety
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
August 2018
Augmented reality and virtual reality education, autotuning PID control, cybersecurity advice, educating engineers
July 2018
Ladder logic best practices and object-oriented programming, safety instrumented systems, enclosure design issues and challenges, process control advice
June 2018
Discrete and process sensor fundamentals, autotuning controls, system integrator roundtable
Edge Computing
This article collection contains several articles on how today's technologies heap benefits onto an edge-computing architecture such as faster computing, better networking, more memory, smarter analytics, cloud-based intelligence, and lower costs.
Data Center Design
Data centers, data closets, edge and cloud computing, co-location facilities, and similar topics are among the fastest-changing in the industry.
PLCs
Programmable logic controllers (PLCs) represent the logic (decision) part of the control loop of sense, decide, and actuate. Featured articles in this digital report compare PLCs and programmable automation controllers (PACs), industrial PCs, and robotic controllers.
SIDB

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

August 2018
SCADA standardization, capital expenditures, data-driven drilling and execution
June 2018
Machine learning, produced water benefits, progressive cavity pumps
April 2018
ROVs, rigs, and the real time; wellsite valve manifolds; AI on a chip; analytics use for pipelines
John O. Ayuk, PE, CFSE, PMP, CAP
Automation Engineer; Wood Group
Doug Baker
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
Data Centers: Impacts of Climate and Cooling Technology
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
Safety First: Arc Flash 101
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
Critical Power: Hospital Electrical Systems
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
Engineers' Choice Awards
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by Control Engineering subscribers.
System Integrator Giants
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
System Integrator of the Year
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
How to Maximize Factory Automation Efficiency with Low Cost Machine Vision
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Wireless Reliability in Harsh Environments
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
Human Factors and the Impact on Plant Safety
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
August 2018
Augmented reality and virtual reality education, autotuning PID control, cybersecurity advice, educating engineers
July 2018
Ladder logic best practices and object-oriented programming, safety instrumented systems, enclosure design issues and challenges, process control advice
June 2018
Discrete and process sensor fundamentals, autotuning controls, system integrator roundtable
Edge Computing
This article collection contains several articles on how today's technologies heap benefits onto an edge-computing architecture such as faster computing, better networking, more memory, smarter analytics, cloud-based intelligence, and lower costs.
Data Center Design
Data centers, data closets, edge and cloud computing, co-location facilities, and similar topics are among the fastest-changing in the industry.
PLCs
Programmable logic controllers (PLCs) represent the logic (decision) part of the control loop of sense, decide, and actuate. Featured articles in this digital report compare PLCs and programmable automation controllers (PACs), industrial PCs, and robotic controllers.
SIDB

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

August 2018
SCADA standardization, capital expenditures, data-driven drilling and execution
June 2018
Machine learning, produced water benefits, progressive cavity pumps
April 2018
ROVs, rigs, and the real time; wellsite valve manifolds; AI on a chip; analytics use for pipelines
John O. Ayuk, PE, CFSE, PMP, CAP
Automation Engineer; Wood Group
Doug Baker
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
Data Centers: Impacts of Climate and Cooling Technology
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
Safety First: Arc Flash 101
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
Critical Power: Hospital Electrical Systems
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
Engineers' Choice Awards
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by Control Engineering subscribers.
System Integrator Giants
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
System Integrator of the Year
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
How to Maximize Factory Automation Efficiency with Low Cost Machine Vision
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Wireless Reliability in Harsh Environments
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
Human Factors and the Impact on Plant Safety
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
August 2018
Augmented reality and virtual reality education, autotuning PID control, cybersecurity advice, educating engineers
July 2018
Ladder logic best practices and object-oriented programming, safety instrumented systems, enclosure design issues and challenges, process control advice
June 2018
Discrete and process sensor fundamentals, autotuning controls, system integrator roundtable
Edge Computing
This article collection contains several articles on how today's technologies heap benefits onto an edge-computing architecture such as faster computing, better networking, more memory, smarter analytics, cloud-based intelligence, and lower costs.
Data Center Design
Data centers, data closets, edge and cloud computing, co-location facilities, and similar topics are among the fastest-changing in the industry.
PLCs
Programmable logic controllers (PLCs) represent the logic (decision) part of the control loop of sense, decide, and actuate. Featured articles in this digital report compare PLCs and programmable automation controllers (PACs), industrial PCs, and robotic controllers.
SIDB

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

August 2018
SCADA standardization, capital expenditures, data-driven drilling and execution
June 2018
Machine learning, produced water benefits, progressive cavity pumps
April 2018
ROVs, rigs, and the real time; wellsite valve manifolds; AI on a chip; analytics use for pipelines
John O. Ayuk, PE, CFSE, PMP, CAP
Automation Engineer; Wood Group
Doug Baker
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
Data Centers: Impacts of Climate and Cooling Technology
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
Safety First: Arc Flash 101
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
Critical Power: Hospital Electrical Systems
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me