Technical requirements

AN4392

4/17

DocID025507 Rev 1

2

Technical requirements

Modulation is either spread spectrum (DSSS, FHSS or a hybrid of the two), or other digital

modulation. Although Bluetooth LE uses the frequency hopping method during

communication, it is not defined as a system using this method (according to Radio

Equipment Regulations, Article 4.17.49.20 [4]).

Maximum output power

The maximum allowed output power is 10 mW (10 dBm) measured in a 1 MHz bandwidth

for a non-FHSS system.

If FHSS is used, the maximum power is 3 mW measured in a 1 MHz bandwidth if the whole

band is used. 10 mW can be used for FHSS systems, but not from 2.427 to 2.47075 GHz,

where the limit is 3 mW.

Frequency tolerance

Frequency tolerance shall be within ± 50 ppm of rated frequency.

Transmitter spurious emissions

Average power of spurious emissions (outside the specified 2.4 GHz band) shall be as

follows:

Frequency bandwidth

The required frequency bandwidth is limited by:

–

83.5 MHz for FHSS or hybrid FHSS/DSSS systems, 26 MHz in other systems.

–

The spreading bandwidth shall be 500 kHz or more in spread spectrum systems.

–

The spreading bandwidth is defined as the bandwidth containing 95% of the

average radiated power.

Table 1. Transmitter spurious emissions

Frequency range

Transmit mask level

< 2387 MHz

- 26 dBm

2387 to 2400 MHz

- 16 dBm

2400 to 2483 MHz

-

2483 to 2496.5 MHz

- 16 dBm

> 2496.5 MHz

- 26 dBm