Low power wide area network protocol

You can refer to SigFox or LoRa.

Hello Chen,

Thanks for the opinion.

Do they need any gateway, such as mobile phone company, to operate?

My idea is to deployment certain personal alert system which range is from 100 to 200 metres.

For Sigfox, you don't need GW and there's operator provide base stations so devices can send messages to those stations to cloud. For Lora, you can use GW provided by operators or build your own GW.