NLOS or non-line of sight link is a specific feature of mobile WiMax technology. It is qualitatively better than line of sight links (LOS) which has been widely utilized on fixed wireless broadband and radio signal transmission. In a line of sight link, signal is directly sent from a base transmitter to the receiver. An obstruction with the line of sight could diminish the strength of the signal thus creating choppy or intermittent connections.
With mobile WiMax NLOS link, frequency signals are distributed through reflection, diffractions, or scattering. The signal therefore can be transmitted effectively through any channels without significant loss of quality. Non-line of sight link capability is one of the basic strengths of mobile WiMax solutions. It enables end-users to access WiMax points even on highly congested areas with lots of physical obstruction. Network providers will find this capability useful because there will be no need to set up multiple base transmitters just to achieve uninterrupted service.
With WiMax NLOS capabilities, the customer premise equipment can be installed indoors without the need for installing additional outdoor antennas to receive transmitter signals. The enhanced wireless solution of WiMax enables NLOS connectivity because of its improved building penetration capability. It will also enable central transmitters to reach WiMax equipments that are farther from the base.
WiMax NLOS capability improved the delivery of wireless services. It also reduced the operating cost of mobile providers and enabled them to provide services to areas that are normally unreachable using line of sight links.