WLL has many advantages over wired systems. They are:
Cost: Wireless systems are less expensive than wired systems. Although the electronics of the wireless transmitter/receiver may be more expensive than those used for wired communications, with WLL the cost of installing kilometers of cable, either underground or on poles, is avoided, as well as the cost of maintaining the wired infrastructure.
Installation time: WLL systems typically can be installed rapidly. The stumbling blocks are obtaining permission to use a given frequency band and finding a suitable elevated site for the base station antennas. Once these hurdles are cleared, a WLL system can be installed in a small fraction of the time required for a new wired system.
Selective installation: Radio units are installed only for those subscribers who want the service at a given time. With a wired system, typically cable is laid out in anticipation of serving every subscriber in a local area.
Security: Much more secure due to digital encryption techniques used in wireless communication.