According to the web search results, the first discovery method used by FortiAP to locate the FortiGate wireless controller in the default configuration is static. This means that the FortiAP sends discovery requests to a preconfigured IP address that the controller owns. This is useful if the FortiAP and the controller are not in the same subnet and other discovery methods will not work. The other discovery methods are used in sequence if the static method fails or is not configured. References:  Advanced WiFi controller discovery | FortiAP / FortiWiFi 7.4.0

A FortiGate unit is an industry leading enterprise firewall. In addition to consolidating all the functions of a network firewall, IPS, anti-malware, VPN, WAN optimization, Web filtering, and application control in a single platform, FortiGate also has an integrated Wi-Fi controller.

The correct way to ensure that the RF channels and transmission power limits are appropriately configured for the remote APs is to create a new FortiAP profile and change the country code settings on the profile. This is because the country code settings determine the legal RF channels and transmission power limits for each country, and they are applied at the FortiAP profile level. By creating a new FortiAP profile for the remote APs, you can specify the correct country code for Germany and assign it to the APs. This will ensure that the APs comply with the local regulations and avoid interference with other devices. Configuring the APs individually by overriding the settings in Managed FortiAPs is not recommended, as it is tedious and error-prone. Configuring the controller for the correct country code for Germany is not possible, as the controller can only have one country code setting, which should match its physical location. Cloning a suitable FortiAP profile and changing the county code settings on the profile is not advisable, as it may cause conflicts with other settings that are specific to the original profile. References:  Secure Wireless LAN course description , [FortiOS 6.4.0 Handbook - Wireless Controller]

According to the web search results, Auto TX Power control is a feature that allows the AP to automatically adjust its transmission power based on the RF environment. The goal is to minimize interference and optimize coverage cells for roaming. When the AP detects any other wireless signal stronger than -70 dBm, it means that there is a potential source of interference nearby, so it will reduce its transmission power until it reaches the minimum configured TX power limit. This will reduce the interference and improve coexistence with other devices. When the AP detects any interference from a trusted neighboring AP stronger than -70 dBm, it means that there is a high density of APs in the area, so it will also reduce its transmission power until it reaches the minimum configured TX power limit. This will balance the load and avoid overlapping coverage areas. References:  AP Transmit Power and Enable Power Reduction with Auto TX ,  Transmit Power and Antenna Configuration ,  Meraki Auto RF: Wi-Fi Channel and Power Management

This frequencies are also used by other licensed applications, wireless LANs have to use a specific method to gain access to certain higher frequencies and this method is known as DFS.

FortiGate, FortiCloud wireless access points (send visitor data in the form of station reports directly to FortiPresence)

The WiFi Client monitor on the FortiGate GUI shows the upstream and downstream link rates of a wireless client, along with other information such as MAC address, SSID, IP address, signal strength, and connection time. The link rates indicate the maximum data rates that the client can achieve in both directions. References:  Secure Wireless LAN Course Description , page 7; [FortiOS 6.4.0 Handbook - Wireless Controller], page 37.

In the SSID choose WPA2-Enterprise authentication.

WSSO is RADIUS-based authentication that passes the user's user group memberships to the FortiGate.

FortiPlanner is a wireless network planning and deployment tool that helps to design and optimize wireless networks based on various parameters, such as floor plans, AP models, coverage areas, and client density. FortiPlanner uses a predictive model in wireless design projects, which means that it estimates the wireless coverage and performance based on mathematical calculations and simulations, without requiring any physical measurements or site surveys. References:  FortiOS 6.4.0 Handbook - Wireless Controller , page 5; [FortiPlanner User Guide], page 9.