CEPT 70-03 and 869.8 channel in South Africa

[Resham Singh]

In South Africa, our radio allocation conforms to CEPT 70-03 in general.

When doing a due diligence exercise, I noticed communications on the 869.8 Mhz band.

CEPT 70-3 allows for 100% duty cycle at 7dBm or <=1% duty cycle at 14dBm. The EU868.cpp code correctly implements this from what I gather.

However, in South Africa, our radio allocation plan only allows 100% duty cycle at 7dBm for some reason. <=1% duty cycle at 14dBm seems to be omitted. I will engage with our licensing regulator to confirm the reason for this.

In the interim, any idea where and how I should I edit the EU868.cpp to specifically not allow 14dBm on the 869.8Mhz (868.7-870Mhz) band?

This seems to be the only issue with the EU868Mhz channel plan for SA.

Thanks
Resham

[Jason Reiss]

Can you provide a link to the file you are trying to edit?

[Resham Singh]

Hi Jason

Here is the link:

Essentially in SA, we cannot transmit at level greater than 7dBm (5mW) in the 869.7-870 Mhz band.

Thanks
Resham

[Resham Singh]

https://os.mbed.com/teams/MultiTech/code/libmDot-dev-mbed5-deprecated//file/0f5a742a08cd/plans/ChannelPlan_EU868.cpp/

• This reply was modified 3 years, 9 months ago by Resham Singh.

[Jason Reiss]

The frequencies used to setup the Channel Plan are located here.
https://os.mbed.com/teams/MultiTech/code/libmDot-dev-mbed5-deprecated//file/0f5a742a08cd/Lora.h/

    const uint32_t EU868_MILLI_1_FREQ_MIN = 868700000;
    const uint32_t EU868_MILLI_1_FREQ_MAX = 869200000;

And used in ChannelPlan_EU868.cpp to setup the duty-cycle band with a max power on lines 201-208.

    band.Index++;
    band.FrequencyMin = EU868_MILLI_1_FREQ_MIN;
    band.FrequencyMax = EU868_MILLI_1_FREQ_MAX;
    band.PowerMax = 14;
    band.TimeOffEnd = 0;
    band.DutyCycle = 1000;
 
    AddDutyBand(-1, band);

The PowerMax is used in SetTxConfig to limit the max power allowed on the channels within the defined band.

Let me know if that helps.

[Author]

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