Long Range Wireless Voice Communication Network

I aim to set up a network for voice communication over an extensive range - 50-80km without using LTE/GSM. This project is primarily for personal use and will involve the use of commercial off-the-shelf devices.

Key Requirements:
- Setting up a wireless network for voice communication over a 50km range.
- Excluding the use of LTE/GSM.
- Use of commercial off-the-shelf devices.
- Security is not a critical concern but optional end to end encryption is prefered.
-use of portable devices using own rechargable power source
-list of products used for 4 terminal users
-i have limited experience with vhf/uhf so the products used should not be for advanced users.

Ideal Skills and Experience:
- Proficiency in setting up long-range voice communication networks.
- Experience in handling commercial off-the-shelf devices for network creation.
- Knowledge of wireless communication technologies beyond LTE/GSM.
- Ability to ensure reliability and efficiency within a 50km range.
- While security is not the main focus, a basic understanding of network security would be advantageous.

Please bid on this project if you have the required expertise and can provide a cost-effective solution for me.