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Use of 470MHz band & power density

In our country, the radio of 470MHz must use with the following restriction.
1. the power should be under 50mW(erp)
2. If the bw less or equal to 200kHz, the PSD should be less than 50mW/200kHZ(erp) otherwise it should be less than 100mW/100kHz(erp)
3. transmit time should less than 1 second
4. the bw should not larger than 500kHz
5. frequency tolerance: 100*10-6
I'm not an expert of communication. I want know the following questions:
1. if I use the datarate of sf6, and the bw of 125000, how should I set my transmiting power? What is the maximum size of my payload?
2. if I use the datarate of sf7, and the bw of 125000, how should I set my transmiting power? What is the maximum size of my payload?
3. if I use the datarate of sf6, and the bw of 500000, how should I set my transmiting power? What is the maximum size of my payload?
4. if I use the datarate of sf7, and the bw of 500000, how should I set my transmiting power? What is the maximum size of my payload?
5. what is psd, and how should I make sure I don't violate the restriction?
Your Country's regulatory authority will define the PSD (power spectral density) in terms of power (dBm) integrated over a fixed bandwidth (Hz, kHz, MHz...) during the period of constant transmission. Similarly there should be a document available that describes the recommended test method. You should also be able to contact your local certification lab for advice.

In terms of calculating the maximum packet size for a given BW / SF, please refer to the LoRa Alliance regional PHY specification (https://lora-alliance.org/resource-hub/rp2-101-lorawanr-regional-parameters) and the LoRa calculators available for both SX127x and SX126x which can be downloaded from the product pages on the Semtech website (https://www.semtech.com/products/wireless-rf/lora-transceivers) and forum library (https://lora-developers.semtech.com/library/product-documents/)

Regards,

Semtech Support