European Telecommunications Standards Institute (ETSI) has released a new frequency band for narrow and broadband ISM-purposes (Industrial, Scientific, and Medical). The 868 ... 870 MHz band is divided into sub-bands according to transmit power (max 0.5W) and duty cycle allowed for the transmitter.
SATEL’s newest version of 3AS uses the 869.4 ... 869.65 MHz frequency band. This band has 10 separate 25 kHz channels for a maximum power of 0.5 W ERP* and 10% of transmitters duty cycle. Transmitter duty cycle and the maximum constant transmission time (max 36 seconds) must be controlled by data terminal equipment. Other features of the modern SATELLINE 3AS version are equivalent with the original 450 MHz version.
Note! Propagation of radio signals at higher frequencies differs from the propagation at lower frequencies. The rule of thumb is that when you double the frequency you cut the communication distance in half. So compared to the 450 MHz version the maximum communication distance is half when SATELLINE 3AS 869 MHz version is used
Please also note:
It is the recommendation ERC/REC 70-03created by the radio communications committee of CEPT, which sets the technical requirements for the licence exempt use of short range devices on harmonised frequency bands around the Europe. CEPT members (spectrum authorities) have to either follow the recommendation in their frequency management or inform the CEPT radio communications committee about any restrictions. Those national restrictions are listed and attached to the ERC/REC 70-03 document.
License exempt 500 mW sub band
The sub band 869.400 - 869.650 MHz on the 869 MHz range is specified for
0.5 Werp (radiated power, in reference with a half wave dipole antenna, 0 dBd = 2.15 dBi). On this band, there are 10 x 25 kHz channels with centre frequencies
= acc. to formula ( 869.400 MHz + 25 kHz/2 ) + N x 25 kHz ; N=0...9