Notice for 2.4GHz Frequency-Range Transmitting Power Limit Adjustment and Relevant Issues
Radio management departments at all provincial and municipal levels and relevant agencies:
In order to adapt to the development of radio communication technology, to provide available frequency range and facility for R&D of new technology and new product, and to meet the need of radio communication service, according to national radio frequency regulations and frequency spectrum application as well as general international technical standards, technical specifications of radio transmitting equipment in 2.4GHz frequency range are adjusted as follows:
1. As from issue date, main technical specifications of radio transmitting equipment between 2.4 - 2.4835 GHz are adjusted as follows:
(1) Equivalent omnidirectional radiation power (EIRP):
When antenna gain＜10dBi: ≤100 mW or ≤20 dBm；
When antenna gain≥10dBi: ≤500 mW or ≤27 dBm。
(2) Max power spectrum density:
1.1 Direct-sequence spread spectrum mode or other mode:
When antenna gain＜10dBi: ≤10 dBm / MHz(EIRP)；
When antenna gain≥10dBi: ≤17 dBm / MHz(EIRP)；
1.2 Hopping frequency mode:
When antenna gain＜10dBi: ≤20 dBm / MHz(EIRP)；
When antenna gain≥10dBi: ≤27 dBm / MHz(EIRP)。
(3) Carrier frequency tolerance:20 ppm
(4) Out of band transmitting power (beyond 2.4-2.4835GHz ):
≤-80 dBm / Hz (EIRP)。
(5) Stray emission (radiation) power (beyond 2.5times channel bandwidth of carrier
wave):
≤-36 dBm / 100 kHz (30 - 1000 MHz)；
≤-33 dBm / 100 kHz (2.4 - 2.4835 GHz)；
≤-40 dBm / 1 MHz (3.4 - 3.53 GHz)；
≤-40 dBm / 1 MHz (5.725 - 5.85 GHz)；
≤-30 dBm / 1 MHz (1 - 12.75 GHz for others).
2. 2.4GHz frequency range is used as common frequency range shared with various radio stations using radio LAN, radio connect system, equipment based on blue-tooth technology, point-to-point or point-to-multipoint spread spectrum communication system and etc.
Radio communication equipment satisfying technical requirements, which shares common frequency between 2.4 - 2.4835 GHz with radiolocation service and non-radio communication equipment (for example scientific and medical equipment) is a main service equipment.
3. Radio frequency part and antenna in radio transmitting equipment within this frequency range must be integrated in design and production. Its external adjustment or control devices are available within technical specifications related to verified models. When using and setting, users cannot modify antenna or additionally add radiofrequency power amplifier without permission.
4. Any radio station using 2.4GHz frequency range shall be in accordance with “Interim Provisions for Micropower (Short Distance) Radio Equipment” (Xin Bu [1998] No.178) issued by the IT Ministry. Furthermore, its radio transmitting equipment must be submitted to state radio administration for approval.
In order to find interference source and make coordination, outdoor radio station using 2.4GHz frequency range should be submitted to radio management department at provincial and municipal level for file.
5. Radio stations within this frequency range won’t be protected if interfered among them. In principle, the operators should settle it by themselves or in negotiatory way. They may request local radio management department to provide assistance in finding interference source.
6. Point-to-point spread spectrum communication station set up in countryside must be submitted to local radio management department for approval. To avoid interference with radio communication equipment such as radio LAN etc, no point-to-point spread spectrum communication station is permissible in densely inhabited districts, for example suburbs close to large and middle cities. Such radio station licensed legally may operate till Dec 31, 2004.
If any conflict with old documents, it is subject to this document.
It is hereby to make this notification.
Aug 23, 2002
