NB-IoT, LoRa, and Zigbee

In the realm of IoT applications, wireless technologies can be categorized into local area networks (LANs) and wide area networks (WANs). LAN technologies primarily include 2.4 GHz WiFi, Bluetooth, and Zigbee, while WAN technologies encompass 2G/3G/4G, NB-IoT (2G), and LoRa (2G). Each of these wireless technologies has distinct advantages and disadvantages, summarized as follows:

NB-IoT

Also known as a simplified version of a mobile module, NB-IoT connects to wide-area networks using SIM cards from mobile operators like China Mobile, China Unicom, and China Telecom. The connection is established through a module/antenna/SIM card integrated unit. Key features include:

• Utilizes a low 2G frequency band with extremely low power consumption, up to 10 years.
• Excellent signal coverage and high capacity, supporting up to 100,000 devices per sector.
• Widely applied in remote metering, logistics, container tracking, and vehicle networking.

Narrowband IoT (NB-IoT) supports low-power devices with cellular data connectivity in wide-area networks, also known as Low Power Wide Area Network (LPWAN).

NB-IoT boasts four main characteristics:

1. Broad Coverage: Improved indoor coverage, with a 20 dB gain over existing networks, equivalent to a 100x increase in coverage area.
2. High Connectivity: Supports up to 100,000 connections per sector, with low latency sensitivity, ultra-low device costs, low power consumption, and optimized network architecture.
3. Lower Power Consumption: NB-IoT module standby time can last up to 10 years.
4. Lower Module Cost: Expected cost per connection module is under $5.

 LoRa

Typical topology: Multiple terminals + 1 gateway. Terminals do not require SIM cards and are placed at the IoT site. The gateway connects with terminals and can directly access home broadband or use a SIM card for wide-area network connectivity with the cloud. A single gateway can support over 10,000 connections with a range of 5-10 kilometers. Suitable for applications with many dispersed yet dense monitoring devices, such as watershed monitoring. Features include: long-distance, low power consumption (long battery life), multi-node, and low cost. Operates on global free bands: 433 MHz (banned by MIIT document 52), 868/915 MHz.

Differences Between NB-IoT and LoRa

Both LoRa and NB-IoT are IoT technologies but have significant differences:

1. Operating Frequency Bands:
   • NB-IoT: Operates on licensed bands, authorized by official bodies. Major operators like China Telecom, China Mobile, and China Unicom are involved, with Huawei also promoting it.
   • LoRa: Operates on unlicensed bands, primarily promoted by non-official internet companies like Alibaba Cloud and Tencent.
2. Data Channel Control and Fees:
   • NB-IoT: Operators control the data channel and charge for usage.
   • LoRa: Enterprises independently build networks without needing to pay operators.
3. User Autonomy:
   • NB-IoT: Modifications to existing communication base stations allow for quick network deployment with operator control.
   • LoRa: Users can deploy LoRa networks independently, faster and at lower cost. Particularly advantageous in areas with weak NB-IoT signals, such as indoor and underground environments.
4. Energy Consumption:
   • LoRa: Offers significant energy savings compared to NB-IoT. For example, a LoRa device with a 1000 mAh battery transmitting once per hour can theoretically last 10 years, while an NB-IoT device under the same conditions would last only about a year.

 Zigbee

Zigbee, also known as Z-Bee, is a new short-range, low-speed, low-power wireless network technology, positioned between wireless tagging technology and Bluetooth. It operates at a bandwidth of 20-250 kbps on the 2.4 GHz band. Zigbee networking has two notable features:

1. High Node Capacity: A Zigbee network can theoretically support up to 65,536 nodes, far exceeding Bluetooth’s 8 and WiFi’s 32.
2. Automatic Network Repair: Any node can communicate with others, and the network automatically repairs itself when nodes join or leave.

Zigbee’s target markets include PC peripherals (mice, keyboards, game controllers), consumer electronics (TVs, VCRs, CD/DVD players), home automation (lighting, gas metering, alarms), toys (electronic pets), healthcare (monitors, sensors), and industrial control (monitors, sensors, automated equipment).