How to Build a DIY WiFi Extender for Better Coverage Using a Raspberry Pi

Improving your WiFi coverage at home can be frustrating when you have dead zones where the signal doesn't reach. An inexpensive solution is to build your own WiFi extender using a Raspberry Pi. In this guide, I'll walk you through the complete process of setting up a Raspberry Pi as a WiFi extender to boost your wireless coverage.

What You'll Need

Here's a list of everything you'll need to complete this project:

• Raspberry Pi - Any model will work, but I recommend Raspberry Pi 3 B+ or newer for the best performance.

• MicroSD Card - At least 8GB for Raspbian operating system.

• Power Supply - Official Raspberry Pi power supply or a quality 3rd party option.

• Ethernet Cable - To connect the Pi to your router initially.

• USB WiFi Adapter - Choose one that supports AP/monitor mode.

• Case - To safely house the Pi. Official case or 3D printed works.

Setting Up the Raspberry Pi

The first step is prepping the Raspberry Pi. Follow these steps:

• Download the Raspbian operating system and flash it onto the microSD card.

• Insert the microSD card into the Pi and connect it to your router using the ethernet cable. This allows internet access for software installation.

• Boot up the Pi and walk through the initial setup prompts to configure Raspbian.

• Enable SSH so you can remotely control the Pi from another device.

• Update the OS packages by running sudo apt update && sudo apt full-upgrade. Reboot after.

• If using the official Raspberry Pi OS, enable the systemd service to allow the WiFi extender software to run automatically on boot.

Installing WiFi Extender Software

Now we can install the software that will turn the Pi into a WiFi extender. Create_AP is an excellent open source tool for this:

• Install it by running: sudo apt install create_ap. Enter your password when prompted.

• Run create_ap --help to see usage info. There are many customization options available.

• For a simple setup, run:

sudo create_ap wlan1 eth0 MyExtender mypassword

• This creates an access point on wlan1 with the SSID MyExtender and password mypassword, bridged to the eth0 wired connection.

• Your Pi is now running as a WiFi extender! The name and password can be customized.

Connecting the USB WiFi Adapter

For maximum flexibility, I recommend adding a powerful USB WiFi adapter to the Pi instead of relying on the built-in wireless.

• With the Pi powered off, plug in your USB WiFi adapter to an available port. Boot up the Pi.

• Identify the name of the USB wireless interface. It will likely be wlan0 or similar.

• Update the create_ap command from earlier to use your USB wireless interface name instead of wlan1.

• Your USB WiFi adapter is now being used as a much more capable wireless extender!

Optimizing Placement

To maximize the extended WiFi range, some experimentation is needed to find the optimal location. Here are some tips:

• Try placing the Pi extender in the center of your home, ideally on the same floor as your main router.

• Avoid obstacles like thick walls, large appliances, and interference from other electronics.

• An elevated placement on top of a bookshelf or table can improve the signal coverage.

• Use WiFi analyzer apps on your phone or laptop to visualize the extended signal strength in different locations.

Wrapping Up

That covers the major steps to build your own DIY WiFi extender with a Raspberry Pi! With very cheap hardware and freely available software, you can significantly improve your home wireless coverage. Remember to experiment with placement and settings to optimize the extended range. Have fun with your new wireless skills!