GB/T 36440-2018 in English

GB/T 36440—2018: In-depth interpretation of the physical layer specifications of low-speed wireless personal area networks with interference resistance

1. Background and significance of the standard

GB/T 36440—2018 specifies the physical layer specifications of low-speed wireless personal area networks with interference resistance operating in the ${174}~{\mathrm{MHz}}{\sim}216~{\mathrm{MHz}},{407}~{\mathrm{MHz}}{\sim}425~{\mathrm{MHz}}$ and $608~\mathrm{MHz}{\sim}630~\mathrm{MHz}$ frequency bands. The standard aims to ensure the reliable communication of biomedical telemetry equipment in complex electromagnetic environments and avoid interference with radio astronomy services.

2. Scope of the standard and applicable scenarios

This standard applies to the development and design of biomedical telemetry equipment operating in the above-mentioned frequency bands. Specifically including:

• General requirements of the physical layer
• Physical layer requirements for O-QPSK modulation
• Physical layer requirements for GFSK modulation

3. Standard framework comparison table

4. Detailed Explanation of Core Technologies

Comparison between O-QPSK Modulation and GFSK Modulation:

• O-QPSK: uses offset quadrature phase shift keying to support higher data rates (250kbit/s and 500kbit/s), suitable for scenarios with high communication performance requirements.
• GFSK: uses Gaussian frequency shift keying, has better anti-interference ability, and is suitable for low-rate and long-distance transmission.

5. Implementation Recommendations

In actual applications, it is recommended to:

1. Choose the appropriate modulation method and frequency band according to the application scenario.
2. Ensure that the equipment meets the RF parameter requirements in the standard (such as EVM, transmit power) to ensure communication quality.
3. Use the CCA mechanism to effectively avoid channel interference and improve network efficiency.