Frequency band division of wireless technology for the Internet of Things

Wireless communication technologies all need certain frequency bands to communicate, just like cars need roads to travel. In the application of the Internet of Things, different countries or regions use different frequencies for wireless technology. To adapt to the development of the Internet of Things, various countries or regions have provided certain frequency bands for the application of the Internet of Things. The following are the frequency bands planned by some countries:

• North America: 902-928MHz
• EU: 863-868MHz
• South Korea: 917.5-923MHz
• Japan: 916.5-927.5MHz
• UK: 915-921MHz

What frequency bands are suitable for China's Internet of Things market? In particular, what frequency bands are suitable for the emerging low-power wide area network (LPWAN) in China?

Frequency of wireless technology

If wireless technologies are divided according to the transmission distance, some common IoT wireless technologies can be divided into the following categories:

LoRa, China LoRa Application Alliance (CLAA) recommends 470~510MHz.

NB-IoT, the mainstream frequency bands in the world are 800MHz and 900MHz. China Telecom will use 800MHz as the preferred frequency band for deploying NB-IoT, China Unicom will choose 900MHz to deploy NB-IoT, and China Mobile may re-cultivate the existing 900MHz frequency band.

Sigfox, Europe and the Middle East: 868MHz (ETSI 300-220), North America: 902MHz (FCC part 15), South America/Australia/New Zealand: 920MHz (ANATEL 506, AS/NZS 4268).

Weightless, as an open standard LPWAN wireless technology, operates in the entire unlicensed Sub-GHz ISM/SRD band and can be deployed globally: 169/433/470/780/868/915/923MHz.

ZETA, a technology developed by Zongxing Technology, can operate in multiple Sub-GHz frequency bands (such as: 433, 470, 500, 787, 868 and 915MHz, etc.) In addition, ZETA can also operate on proprietary frequency bands by changing the configuration.

Wi-Fi and Bluetooth operate at 2.4GHz, a universal frequency band worldwide.

NFC: It is reported that the Ministry of Industry and Information Technology will release near-field communication technology standards based on 13.56MHz.

Z-Wave, in China, operates at a frequency of 868.40 MHz and complies with the CNAS/EN 300 220 standard.

ZigBee, Thread, ISA100.11a and other specifications are all extended based on IEEE 802.15.4. General IEEE 802.15.4 devices use 868/915/2400MHz frequencies.

In addition to 2.4GHz, IoT wireless technologies are mostly based on the Sub-GHz frequency band. What are China's regulations and requirements for existing wireless spectrum?

Radio frequency regulations and requirements

There are several regulations, requirements and standards related to the Internet of Things:

• Radio Frequency Allocation Regulations of the People's Republic of China
• Technical requirements for micropower (short-range) radio equipment
• 《IEEE Std 802.15.4c-2009》
• Notice on increasing the operating frequency of micro-power (short-range) radio applications in the 800MHz band
• Technical requirements for micropower (short-range) radio equipment

In 2005, the Ministry of Industry and Information Technology revised and issued the "Technical Requirements for Micropower (Short Range) Radio Equipment" (Document No. [2005] 423). The "Requirements" divided the equipment into 14 categories:

Among them, (iii) wireless microphones and civil radio measuring instruments and other types of equipment

It is used for audio-visual training in education and cultural departments, auditory assistance in public places such as cinemas, concert halls, conference rooms and for people with disabilities, and as a small broadcasting device in tourist areas.

The 470-510MHz frequency band can be used as a frequency band for civil radio measuring instruments, provided that the transmitter operating time does not exceed 5 seconds when transmitting data.

If the frequency used is the same as the frequency of the local sound or television broadcasting station, it shall not be used locally; if it causes interference to the local sound or television broadcast reception, it should be stopped immediately and can only be used again after the interference is eliminated or adjusted to an interference-free frequency.

To avoid interference with biomedical telemetry equipment, wireless microphones are not allowed to be used in hospitals. Wireless microphone manufacturers must specify this requirement in their product manuals.

1. Frequency and transmission power:

1) Frequency: 87-108 MHz

Transmit power limit: 3mW(erp)

2) Frequency: 75.4-76.0MHz, 84-87MHz

Transmit power limit: 10mW (erp)

3) Frequency: 189.9-223.0MHz

Transmit power limit: 10mW (erp)

4) Frequency: 470-510MHz, 630-787MHz

Transmit power limit: 50mW (erp)

2. Occupied bandwidth: no more than 200kHz

3. Frequency tolerance: 100×10-6

(11) Wireless control devices for various types of civilian equipment shall not be used for wireless control of toys, models, etc.

1. Frequency: 314-316MHz, 430-432MHz, 433.00-434.79MHz

Transmit power limit: 10mW (erp)

Occupied bandwidth: no more than 400kHz

2. Frequency: 779-787MHz,

Transmit power limit: 10mW (erp)

IEEE Std 802.15.4c-2009

According to the description from Baidu Encyclopedia, IEEE802.15.4C was jointly promoted by China Electronics Standardization Institute, Beijing University of Aeronautics and Astronautics, Tsinghua Tongfang, Huawei Technology Co., Ltd. and Beijing Weixin Zijing Technology Co., Ltd. The IEEE 802.15.4C standard was officially released on March 29.

F.3.2 Radio control devices for all kinds of civil equipment

Radio controlled devices are prohibited for use for toys and models, but can be used for civilian equipment for the following working frequencies:

a), Working frequency: 314–316 MHz, 430–432 MHz, and 433.00–434.79 MHz

Transmitting power limit: 10 mW (EIRP)

Occupied bandwidth: no greater than 400 kHz

b), Working frequency: 779–787 MHz

Transmitting power limit: 10 mW (EIRP)

No occupied bandwidth requirement

Notice on increasing the operating frequency of micro-power (short-range) radio applications in the 800MHz band Letter No. [2008] No. 44

In order to promote the development of micro-power (short-range) radio technology and meet social needs, based on the frequency division and usage in my country, after research, the 868-868.6 MHz operating frequency is added for micro-power (short-range) radio applications. The specific matters are notified as follows:

1. Radio frequency requirements for micro-power (short-range) radio equipment in this frequency band:

1. Transmit power limit: 5mW (erp);

2. Duty cycle limit of transmitted signal: 1%;

3. Carrier frequency tolerance: 100×10-6.

2. Radio equipment in this frequency band is classified as "radio control devices for various types of civilian equipment" in the "Notice on Issuing the Technical Requirements for Micropower (Short-Range) Radio Equipment (Ministry of Information Technology No. 423 [2005])".