How is IoT used in wireless communication?

Introduction

The Internet of Things (IoT) relies heavily on wireless communication technologies to interconnect smart devices and objects. Wireless provides the flexible, low-cost connectivity fabric that enables the wide range of IoT applications transforming homes, cities, industries, transportation and more. This article explores how various wireless technologies are utilized in IoT systems and the considerations around selecting the best approach.

IoT Wireless Communication Requirements

IoT solutions have diverse connectivity requirements that span long range, high bandwidth, mesh networking, low power, and mobility:

• Range – Connectivity of sensors across a home, factory floor, city grid, agricultural field, etc.
• Bandwidth – Video security cameras require high throughput wireless links.
• Mesh Networking – Extending reach by device-to-device multi-hop routing.
• Low Power – Enabling battery-powered operation for years before maintenance.
• Mobility – Tracking goods in transit or medical assets in a hospital.
• Scale – Potentially thousands of nodes even in a local IoT network.
• Cost – Inexpensive wireless hardware to enable mass deployments.
• Standards – Interoperability across devices from many vendors.

No single wireless technology optimally meets all of these needs. IoT systems utilize multiple wireless protocols combined in a complementary way.

Wireless Communication Protocols for IoT

Several wireless technologies are commonly used for IoT connectivity:

Cellular

• 2G/3G/4G/5G – Provides wide area connectivity using existing cellular infrastructure. IoT-optimized LTE variants called LTE-M and NB-IoT exist.
• Benefits – Ubiquitous coverage, mobility, security, bandwidth
• Limitations – Cost, power consumption

WiFi

• 802.11 – Ubiquitous wireless local area networking technology. IoT uses low power WiFi variants like 802.11ah.
• Benefits – Commonly available, supports IP networking, high bandwidth
• Limitations – Power hungry, limited range

Bluetooth

• Bluetooth LE – Low energy version of Bluetooth ideal for periodic IoT sensor data.
• Benefits – Ubiquitous, very low power, low cost, standards-based
• Limitations – Short range under 100m. Low bandwidth.

LoRaWAN

• LoRaWAN – Long range, low power wireless protocol using LoRa modulation on sub-GHz bands.
• Benefits – Long range (kms), low power, secure, operates below 1 GHz
• Limitations – Lower bandwidth, higher module cost

Proprietary RF

• Proprietary – Custom wireless protocols using freely available ISM bands like 900 MHz or 2.4 GHz.
• Benefits – Optimized for specific application needs around range, power, cost.
• Limitations – Vertical integration required. No interoperability.

LPWAN

• Sigfox, Ingenu – Ultra narrowband, long range technologies for basic IoT data.
• Benefits – Long range, low power, low cost connectivity
• Limitations – Very low bandwidth. Limited data.

This variety of wireless options provides flexibility to match the right connectivity to application requirements.

Key Considerations for Wireless IoT

Key factors to evaluate when selecting wireless technologies for an IoT solution include:

Power Consumption

Battery powered devices may need to operate for years before maintenance. Low power wireless like Bluetooth LE, LoRaWAN, and LPWAN reduce power use.

Range Requirements

Sensors spread across large physical spaces require long range wireless connectivity, even km-scale for rural settings. Cellular, LoRaWAN provide this.

Bandwidth Needs

Video security cameras require WiFi or 4G LTE class bandwidth versus simple temp sensors that just need low bandwidth LoRaWAN uplinks.

Cost Sensitivities

Bluetooth LE provides the most cost efficient wireless modules. LPWAN networks have low subscription costs for massive sensor deployments.

Mobility

Tracking assets in motion requires cellular or WiFi. Fixed assets can use LoRaWAN, Bluetooth LE, or other lower power approaches.

Security Concerns

Public networks require proven secure connectivity like LTE/5G. Private networks on proprietary RF or LoRaWAN also enable encryption.

Interoperability Needs

WiFi, Bluetooth LE, and LoRaWAN are standardized for interoperability. Proprietary RF limits to single vendor deployments.

Combining technologies is common to meet varied connectivity needs. For example, sensors could use Bluetooth LE to a gateway, then LoRaWAN backhaul to the cloud.

Wireless Technologies for Common IoT Applications

Different vertical IoT applications impose unique wireless requirements:

Smart Home – Primarily uses WiFi with supplemental Bluetooth LE, ZigBee, or proprietary mesh networks to link low-bandwidth sensors and smart home devices.

Industrial IoT – Requires multi-km range on private networks with combinations of proprietary wireless, LoRaWAN, and cellular for backhaul. Reliability and security are critical.

Smart Cities – Take advantage of existing infrastructure using 4G/5G networks for connectivity of city assets. LoRaWAN also sees adoption in city-scale deployments.

Agriculture IoT – Connectivity of rural agricultural assets is enabled by LoRaWAN, Sigfox, and proprietary wireless which provide range of up to 10 km or beyond.

Connected Vehicles – Leverage 4G LTE, emerging 5G networks, and on-board WiFi hotspots for vehicles. DSRC provides short range vehicle-to-vehicle links. Bluetooth LE connects in-cabin.

Retail and Inventory – Stores use a combination of WiFi, Bluetooth beacons, RFID, and LPWAN to link devices managing inventory, logistics, and merchandise flow.

Healthcare IoT – Hospitals employ WiFi supplemented by proprietary RF for reliable indoor asset tracking of medical equipment, and Zigbee devices for long battery life.

The diversity of vertical applications demonstrates why IoT takes advantage of nearly the full spectrum of wireless technologies today.

Wireless Communication Protocols for IoT – Comparison

Protocol	Frequency	Range	Bandwidth	Power	Security
2G	850MHz, <br> 1900MHz	Wide area	UP to 0.3 Mbps	High	Strong
3G	850MHz, <br> 1900MHz	Wide area	Up to 14 Mbps	High	Strong
4G LTE	Sub 1 GHz, <br> 2.4GHz	Wide area	Up to 300 Mbps	High	Strong
5G NR	Sub 6 GHz, <br> mmWave	Wide area	Multi-Gbps	Medium	Strong
WiFi	2.4 GHz, <br> 5 GHz	Up to 100m	Up to 1 Gbps	High	WPA2 Encryption
Bluetooth LE	2.4 GHz	Up to 50m	Up to 2 Mbps	Very Low	128-bit AES
LoRaWAN	Sub 1 GHz	2 – 15 km	0.3 – 50 kbps	Very Low	AES 128 Encryption
Sigfox	Sub 1 GHz	3 – 50 km	100 bps	Very Low	Proprietary
Proprietary ISM RF	315/433/868/915MHz, <br> 2.4GHz	Up to 2 km	Up to 1 Mbps	Low	Custom Security

Optimizing Wireless Coexistence

With various wireless technologies potentially deployed in proximity, steps must be taken to minimize interference between protocols sharing frequency bands:

• Proper RF site survey and planning of wireless coverage areas
• Frequency channelization optimization and allocation
• Transmit power level adjustments to minimize overlap
• Scheduling of transmission activity windows
• Prioritizing co-located traffic based on quality of service needs
• Adding physical isolation between nearby wireless infrastructure
• Leveraging directional antennas and spatial separation

Testing and adjustments after deployment can optimize coexistence and performance.

The Role of LP-WAN for IoT Wireless Connectivity

LP-WAN (Low Power Wide Area Network) technologies like LoRaWAN and Sigfox provide a uniquely optimized combination of long-range wireless connectivity and low power operation:

• Enable battery lifetimes up to 10 years from a single AA battery
• Provide wireless coverage across entire cities, agricultural areas, and industrial sites
• Operate in license-free sub-1GHz frequency bands
• Leverage a star network topology with distributed gateways
• Offer strong security and interference resistance
• Support millions of end node devices
• Enable low cost connectivity at approximately $5 per node
• Sustain excellent range even in urban areas and indoor locations
• Provide sufficient thoughput for typical IoT sensor data
• Maintain robustness at very low transmit power levels

LP-WAN fills a technology gap between short range protocols like Bluetooth LE and wide area cellular networks. This drives adoption for water metering, asset tracking, agricultural monitoring, and smart city applications.

Future Outlook for Wireless IoT Connectivity

The landscape of wireless technologies for IoT continues to rapidly evolve:

• 5G will provide higher performance cellular connectivity especially benefiting high bandwidth video and mobile IoT uses
• WiFi 6 increases speed, density, and efficiency of wireless local networking for IoT
• Bluetooth 5 improves range, broadcasting, and mesh capabilities of Bluetooth LE
• Thread and Zigbee will gain adoption in smart home and building automation
• NB-IoT and LTE-M extend cellular capabilities for low power wide area IoT
• Carrier aggregation across multiple wireless protocols to enhance reliability and throughput
• Edge computing will distribute intelligence into the IoT network lowering wireless data needs
• New spectrum like CBRS and 6 GHz bands will expand available wireless capacity

Conclusion

IoT is driving adoption of a diverse palette of wireless technologies to serve the connectivity needs of smart objects. Factors around power, range, bandwidth, mobility, scale, and cost dictate the optimal wireless approach for specific applications. Ongoing enhancement of wireless protocols and spectrum availability will support the growth of IoT innovations transforming our infrastructure, industries, homes and cities. Comprising the communication fabric tying everything together will be standards-based, IP-connected wireless networks enabling the promise of the Internet of Things.

IoT Wireless Communication – Frequently Asked Questions

What is the difference between LPWAN and WAN?

LPWAN refers to Low Power Wide Area Network technologies designed specifically for wireless IoT sensors. This includes LoRaWAN and Sigfox. WAN more broadly means any wide area network including cellular networks.

Which wireless technology has the longest range for IoT?

Sigfox and LoRaWAN can provide wireless connectivity exceeding 50km in rural areas. Proprietary sub-GHz networks can also attain multi-km ranges suitable for wide area IoT.

Do IoT devices support WiFi?

Some do – WiFi provides high bandwidth wireless connectivity suitable for IoT video cameras, gateways, and devices requiring faster data rates. Low power WiFi variants help address high power consumption.

What is 5G NR?

5G NR stands for Fifth Generation New Radio. It defines the global standard for upgraded 5G cellular networks with benefits like multi-Gbps speeds, ultra low latency, and improved support for massive IoT device density.

Which wireless protocol offers the lowest power consumption?

Bluetooth LE currently enables the lowest power wireless communication, allowing IoT sensors to run for years on small batteries. However, new LPWAN technologies like NB-IoT are competitive on power usage.