ARF868 Radio Modems - User guide version V1.6
2.3. Radio specifications
2.3.1 Introduction to the radio requirements
The modems use the European frequency band 863-870MHz. This frequency band is segmented into different sub-bands each with their own
regulatory requirements both in terms of power, spectral bandwidth, and use of the spectrum. ARF868 modems accept these regulatory require-
ments.
2.3.1.1
Sub-bands
Each sub-band is defined by a minimum and maximum frequency. In addition, the maximum authorised power and the maximum Duty Cycle are
defined separately for each sub-band.
2.3.1.2
Duty Cycle
The purpose of the Duty Cycle ratio is to make sure that no application can occupy a frequency band for more than a certain percentage of the
time. The duty cycle defines a maximum percentage of time (expressed in percentages of any period of hours during which a modem is autho-
rised to transmit. The limitation of the duty cycle should be monitored by the terminal equipment connected to the modem. Please contact Adeu-
nis RF for your calculations of your "air" occupation time.
2.3.1.3
Schematic representation of the requirements of the 863-870MHz frequency band
The table below is a schematic representation of the use of the 863-870MHz frequency band as used by the Adeunis RF ARF868 model.
Power (mW)
500
25
10
5
Caution: this table is non-contractual and is subject to changes in regulations.
2.3.2 ARF868 modem operating modes
ARF868 modems have two operating modes:
•
1 standard mode dedicated to very long ranges and for which immunity to jammers is optimum.
1 ARFx3Pro mode which ensures "air" compatibility with the whole of the Adeunis RF ARFx3Pro modem range.
•
The default communication mode is the standard mode. As soon as it is switched on the modem is capable of transmitting and receiving data
with the parameters in its memory (*).
By default, the modem is in permanent listening mode of the RF interface and the UART port.
•
As soon as a frame from the RF link is demodulated, its content is transmitted to the UART port
•
As soon as a character chain is detected on the UART port, it is transmitted to the RF link.
(*): On first switching on the parameters are the default parameters (or factory settings). At subsequent switchings on the parameters used are
those last memorised with the AT&W command (see § 5.2 AT Commands).
SRD
SRD
1%
0.1%
SRD
SRD
0.1%
10%
SRD
100%
SRD : Short Range
Devices
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